Monoterpenes and Their Derivatives-Recent Development in Biological and Medical Applications

Integration of feature-based molecular networking and high-definition data-dependent acquisition for the comprehensive multicomponent characterization of Honghua Xiaoyao Tablet

Systematically identifying the chemical constituents in complex matrices is a challenge due to the inherent characteristics of compounds. The combination of liquid chromatography-tandem mass spectrometry (LC-MS) and classical molecular networking (CLMN) is a powerful technology for annotating small molecules. However, the low coverage from inappropriate acquisition modes and the inseparability of isomeric compound nodes still hinders the comprehensive metabolite characterization. A novel strategy that integrated high-definition data-dependent acquisition (HDDDA) from traveling-wave ion mobility mass spectrometry (TWIMS) and feature-based molecular networking (FBMN) was developed to improve chemical component characterization and enhance isomeric component discernment. The data-dependent acquisition (DDA) and HDDDA, were effectively and visually evaluated by CLMN and FBMN via the number of nodes, clustered nodes and clusters. Moreover, the efficiency of the three strategies was validated. The results strongly demonstrated that the HDDDA-FBMN strategy improves MS coverage and offers significant advantages for isomer identification. With the assistance of the UNIFI platform, the developed strategy was successfully applied to systematically investigate the chemical profile of Honghua Xiaoyao Tablet (HHXYT), a traditional folk empirical prescription for treating various gynecological diseases. 184 compounds were unambiguously identified or tentatively characterized, including 12 pairs of isomers, and two unreported compounds. In conclusion, this hybrid approach achieves dimensionally enhanced MS data acquisition and visual recognition of isomeric compounds, accelerating the structural characterization in complex systems. We anticipate that HDDDA-FBMN strategies will be a flexible and versatile tool for the chemical components in a complex system of TCMs.

Natural products target pyroptosis for ameliorating neuroinflammation: A novel antidepressant strategy

BACKGROUND

Depression is a common mental disorder characterized by prolonged loss of interest and low mood, accompanied by symptoms such as sleep disturbances and cognitive impairments. In severe cases, there may be a tendency toward suicide. Depression can be caused by a series of highly complex pathological mechanisms; However, its key pathogenic mechanism remains unclear. As a novel programmed cell death (PCD) pathway and inflammatory cell death mode, pyroptosis involves a series of tightly regulated gene expression events. It may play a significant role in the pathogenesis and management of depression by modulating neuroinflammatory processes. In addition, a large number of studies have shown that various pharmacologically active natural products can regulate pyroptosis through multiple targets and pathways, demonstrating significant potential in the treatment of depression. These natural products offer advantages such as low costs and minimal side effects, making them a viable supplement or alternative to traditional antidepressants. In this review, we summarized recent research on natural products that regulate pyroptosis and neuroinflammation to improve depression. The aim of this review was to contribute to a scientific basis for the discovery and development of more natural antidepressants in the future.

METHODS

To review the antidepressant effects of natural products targeting pyroptosis-mediated neuroinflammation, data were collected from the Web of Science, ScienceDirect databases, and PubMed to classify and summarize the relationship between pyroptosis and neuroinflammation in depression, as well as the pharmacological mechanisms of natural products.

RESULTS

Multiple researches have revealed that pyroptosis-mediated neuroinflammation serves as a pivotal contributory factor in the pathological process of depression. Natural products, such as terpenoids, terpenes, phenylethanol glycosides, and alkaloids, have antidepressant effects by regulating pyroptosis to alleviate neuroinflammation.

CONCLUSION

We comprehensively reviewed the regulatory effects of natural products in depression-related pyroptosis pathways, providing a uniquely insightful perspective for the research, development, and application of natural antidepressants. However, future research should further explore the modulatory mechanisms of natural products in regulating pyroptosis, which is of great importance for the genration of effective antidepressants.

Antibacterial Activity of Selected Essential Oil Components and Their Derivatives: A Review

Essential oils (EOs) are gaining ground and have been intensively studied due to their widespread use in the pharmaceutical, food, and cosmetics industries. The essential components of EOs have been recognized for diverse therapeutic activities and have gained significant attention for their potential antibacterial activities. Despite the popularity of EOs and potent biological properties, their bioactive components and their derivatives are still not comprehensively characterized. This review explores the antibacterial efficacy of selected EO components and their derivatives, focusing on monoterpenes chosen (i.e., carvacrol, menthol, and thymol) and phenylpropanoids (i.e., cinnamaldehyde and eugenol). Furthermore, this review highlights recent advancements in developing derivatives of these EO components, which have shown improved antibacterial activity with reduced toxicity. By summarizing recent studies, this review reveals the potential of these natural compounds and their derivatives as promising candidates for pharmaceuticals, food preservation, and as alternatives to synthetic antibiotics in combating bacterial resistance.

Positive Correlation Between Serum Limonene Levels and Muscle Health in a Representative Adult Population in the United States

Background/Objectives: Monoterpenes, a class of organic compounds with the molecular formula C10H16, have garnered significant attention for their potential medicinal benefits. Emerging evidence suggests they may positively influence skeletal muscle function. However, the impact of monoterpene exposure on muscle strength and mass in humans remains unclear. Methods: To explore this relationship, we analyzed data from 1202 adults (aged ≥ 18 years) who participated in the 2013-2014 National Health and Nutrition Examination Survey (NHANES), focusing on serum levels of three specific monoterpenes-α-pinene, β-pinene, and limonene-and their association with hand grip strength and lean muscle mass. Results: Our analysis revealed that, except for test 2 of hand 1, all grip strength measures showed a positive correlation with ln-limonene levels. The β coefficient for combined grip strength was 2.409 (S.E. = 0.891, p = 0.015). Positive associations were also found between serum limonene levels and lean muscle mass. The β coefficient for the Appendicular Skeletal Muscle Mass Index (ASMI) was 0.138 (S.E. = 0.041, p = 0.004). Furthermore, combined grip strength and ASMI significantly increased across limonene quintiles (p for trend = 0.005 and 0.006, respectively). However, none of the three monoterpene levels showed a significant association with clinically defined low muscle mass or low muscle strength. Conclusions: Our findings suggest a plausible association between exposure to limonene, hand grip strength, and lean muscle mass among adults in the United States. Further investigation is needed to fully understand the underlying mechanisms and medical significance of this association.

The Reaction of Fenchone and Camphor Hydrazones with 5-Acyl-4-Pyrones as a Method for the Synthesis of New Polycarbonyl Conjugates: Tautomeric Equilibrium and Antiviral Activity

Selective synthesis of polycarbonyl conjugates of (+)-fenchone and (+)-camphor was carried out (44-91 % yields) via the ring-opening transformation of 5-acyl-4-pyrones with hydrazones of the corresponding monoterpenoids. A strong influence of the hydrazone fragment on the observed tautomeric equilibrium of the tricarbonyl system was shown. Although the major tautomer of the conjugates is the acyclic polycarbonyl form, the camphor-based conjugates undergo new type of ring-chain tautomerism, diketoenaminone-dihydropyridone equilibrium, and predominantly exist in the cyclic dihydropyridone form in DMSO-d6. The polyketones can undergo intramolecular cyclization to form N-amino-4-pyridones in high selectivity. In vitro screening for activity against the influenza virus H1 N1 and vaccinia virus was estimated for the obtained conjugates. The (+)-fenchone derivatives demonstrated the higher activity against vaccinia virus than camphor derivatives. The conjugate, which was prepared from diethyl isochelidonate and hydrazone (+)-fenchone, showed the highest activity against vaccinia virus (SI=17).

Catalytic Transformation of Biomass into Sustainable Carbocycles: Recent Advances, Prospects, and Challenges

Organic compounds bearing one or more carbocycles in their molecular structure have a discernible presence in all major classes of organic products of industrial significance. However, sourcing carbocyclic compounds from exhaustible, anthropogenic carbon (e. g., petroleum) raises serious concerns about sustainability in the chemical industries. This review discusses recent advances in the renewable synthesis of carbocyclic compounds from biomass components following catalytic pathways. The mechanistic insights, process optimizations, green metrics, and alternative synthetic strategies of carbocyclic compounds have been detailed. Moreover, the renewable syntheses of carbocycles have been assessed against their existing synthetic routes from petroleum for better perspectives on their sustainability and technological preparedness. This work will assist the researchers in acquiring updated information on the sustainable synthesis of carbocyclic compounds from various biomass components, comprehending the research gaps, and developing superior synthetic processes for their commercial production.

Bioactive Ion-Confined Ultracapacitive Memristors with Neuromorphic Functions

The field of bioinspired iontronics, bridging electronic devices and ionic systems, has multiple biological applications. Carbon-based ultracapacitive devices hold promise for controlling bioactive ions via electric double layers due to their high-surface-area and biocompatible porous carbon electrodes. However, the interplay between complex bioactive ions and porous carbons remains unclear due to the variety of structures of bioactive ions present in biological systems. Herein, we investigate the adsorption behavior of a series of bioactive ammonium-based cations with varying alkyl chain lengths in nanoporous carbons. We find that strong physisorption results from the synergistic hydrophobic interaction and electrostatic attraction between porous carbons (with a negative zeta potential) and bioactive cations. Bioactive cations with varying alkyl chain lengths can be irreversibly physically adsorbed and confined within nanoporous carbons resulting in anion enrichment and depletion during electric polarization. This situation, in turn, results in a characteristic memristive behavior in all-carbon capacitive ionic memristor devices. Our findings highlight the relationship between the resistance state of the memristor and ion adsorption mechanisms in all-carbon capacitive devices, which hold potential for future transmitter delivery, biointerfacing, and neuromorphic devices.

Larvicidal and Oviposition Activity of Commercial Essential Oils of Abies sibirica Ledeb., Pogostemon cablin (Blanco) Benth., Juniperus communis L. and Their Combinations Against Aedes aegypti

Aedes aegypti is a vector responsible for the transmission of various arboviruses and is considered by the World Health Organization to be one of the main public health problems in the world. This study evaluated the larvicidal and oviposition activity of essential oils from Abies sibirica, Pogostemon cablin and Juniperus communis and their formulations. Chromatographic analysis by GCMS identified a total of 28, 52 and 18 compounds for the oils of the species A. sibirica, J. communis and P. cablin, respectively. The larvicidal bioassays showed an LC50 of 67.53 ppm, 92.45 ppm and 35.95 ppm, respectively, for A. sibirica (A), J. communis (J) and P. cablin (P) as well as their binary (J + P, 39.50 ppm; A + P, 51.64 ppm) and ternary (A + J + P, 66.99 ppm) formulations. These oils and formulations also showed deterrent activity at the larvicidal concentrations tested (A. sibirica: OAI: -0.41; J. communis: OAI: -0.31; P. cablin: OAI: -0.62; A + J + P: -0.30; A + P: -0.68; A + J: -0.29; and J + P: -0.30). The oils and their formulations are a potential larvicidal source for mitigating the proliferation of diseases by this vector.

The Ion Formation and Quantitative Response of Isoprene, Monoterpenes and Terpenoids in Ion Mobility Spectrometry with Atmospheric-Pressure Chemical Ionization as a Function of Temperature

Ion mobility spectrometry is successfully used as a sensor technology for different applications. A feature of this method is that characteristic ion mobility spectra are obtained for each measurement rather than a sum signal. The spectra result from the different drift velocities of ions in a drift tube at atmospheric pressure. In this study, we investigated the ion formation processes and the quantitative response of isoprene, monoterpenes and monoterpenoids as a function of the temperature of the spectrometer using a tritium ionization source. These substances are important target analytes in atmospheric monitoring and in the analysis of essential oils in different matrices. A drift tube temperature above 120 °C permitted the most sensitive detection of isoprene and monoterpenes, while 80 °C was sufficient for the sensitive detection of most terpenoids. Dimer ions were formed for isoprene over the whole temperature range. The ionization processes of monoterpenes and terpenoids were strongly influenced by the temperature. At temperatures of 40 °C, adduct ions were formed in addition to MH+ ions for monoterpenes. Enhanced temperatures provided a single peak with the same drift time for all monoterpenes. Structural differences influenced the ion formation of terpenoids, and much more complex spectra were obtained. The nature of the product ions changed depending on the temperature.

Metabolic engineering of the borneol and camphor degradation pathways in Pseudomonas to produce optically pure bicyclic monoterpenes

Borneol, a medicinally important bicyclic monoterpene, facilitates drug transport across mucous membranes and the blood-brain barrier. Derivatives of borneol and camphor also have numerous biomedical applications. Borneol is currently industrially synthesized via the conversion of turpentine and α-pinene. However, the major product is racemic isoborneol rather than racemic borneol. Both borneol and isoborneol are degraded by the soil bacterium Pseudomonas via a well-established degradation pathway. Two indigenous Pseudomonas strains were used to convert racemic isoborneol to other optically pure bicyclic monoterpenes here. Our results showed that deletion of the camE2,5 gene alone from the strain TCU-HL1 genome led to the complete loss of borneol and camphor degradation ability. Knockout of both camE2,5 and bdh1 (TCU-HL1Δbdh1ΔcamE2,5) restored the degradation capability as the role of Bdh1 was replaced by that of Bdh2. This mutant converted racemic isoborneol into an optically pure bicyclic monoterpene, 2,5-diketocamphane, with a 45 % recovery yield. RT-qPCR results suggested that camE2,5 expression plays a pivotal role in regulating the borneol/camphor degradation cluster. While (+)-borneol, (-)-borneol and (+)-camphor can be obtained from plants for mass production purposes, (-)-camphor cannot be obtained in the same manner. P. monteilii TCU-CK1 converted racemic isoborneol into (-)-camphor and 3,6-diketocamphane, with 15 % and 10 % recovery yields, respectively. In conclusion, we report the role of camE2,5 in regulating the borneol/camphor degradation operon and biotransformation methods to produce several optically pure bicyclic monoterpenes.

Application of terpenoids for the remediation of environmental water polluted with bisphenol A and its analogs using an in silico approach

Nowadays, there is a global concern over water quality and the impact of contamination on both natural ecosystems and human well-being. Plastics, ubiquitous in modern life, may release harmful chemicals when they reach aquatic environments. Among them, bisphenol A (BPA) and its alternatives, such as bisphenol S (BPS), bisphenol F (BPF), and others, are of special concern because their presence in water systems can have detrimental effects on human health and aquatic organisms due to their endocrine-disrupting properties. This study explores the potential of terpenoids, sustainable and environmentally friendly solvents, for efficiently removing bisphenols from contaminated environmental water. Using an in silico approach based on the Conductor-like Screening Model for Realistic Solvents (COSMO-RS) theory, more than 30 terpenoids were screened, and carvone was found to be an excellent candidate due to its high solvent capacity and low toxicity. The impact of pH, temperature, stirring conditions, and sample:extractant phase ratios on the extraction efficiency were investigated. A design of experiments revealed optimal conditions for the extraction process and demonstrated that carvone can effectively extract bisphenols (nearly 100 % for most of them) under a wide range of conditions, showing the robustness and efficiency of the extraction method, even in environmental samples. The paper provides valuable insights into the potential of terpenoids, specifically carvone, as a sustainable and eco-friendly solvent for removing bisphenol contaminants from environmental water bodies. The findings of this study offer a promising solution to address water contamination issues, aligning with the principles of Green Chemistry and contributing to a more environmentally responsible approach to water remediation.

Rosiridin Protects Against Aluminum Chloride-Induced Memory Impairment via Modulation of BDNF/NFκB/PI3K/Akt Pathway in Rats

Background and Objectives: Rosiridin is a monoterpene with outstanding monoamine inhibitory activity that is useful to treat depressive episodes and rapid-onset dementia. The current investigation aims to evaluate the neurologically protective impact of rosiridin, which opposes aluminum chloride (AlCl3) and causes memory dysfunction in rats. Materials and Methods: Memory impairment was developed in Wistar rats by administering AlCl3 (100 mg/kg p.o.) orally for 42 days and then supplemented with rosiridin at 10 and 20 mg/kg/p.o. Upon completion of the investigation, the behavior factor was performed utilizing the Y-maze, Morris Water Maze, and open field tests. Estimating numerous biological factors, such as nitric oxide (NO), oxidative stress (malondialdehyde MDA), acetylcholinesterase (AChE), butyrylcholinesterase levels (BuChE), antioxidants (glutathione GSH, catalase CAT, and superoxide dismutases SODs) and neurotransmitter (serotonin-5HT, dopamine-DA, acetylcholine-Ach) in the brain. Furthermore, interleukin-6 (IL-6), IL-1β, tumor necrosis factor (TNF-α), brain-derived neurotrophic factor (BNDF), nuclear factor kappa B (NFᴋB), phosphatidylinositol 3-kinase (PI3K), and pAkt were assessed in the diffused brain cells. Results: The rosiridin-treated group significantly improved in terms of behavioral parameters, including in the Y-maze, Morris Water Maze, and open field tests. Further, rosiridin restored biochemical parameters, including NO, oxidative stress AChE, BuChE, antioxidants, neurotransmitters, IL-6, IL-1β, TNF-α, BNDF, NFᴋB, PI3K, and pAkt compared to AlCl3. Conclusions: The current investigation reveals that rosiridin could ameliorate the impairment of memory that AlCl3 causes in rats via improvements in behavioral and restored biochemical parameters.

Monoterpene Hydroxy Lactones Isolated from Thalassiosira sp. Microalga and Their Antibacterial and Antioxidant Activities

Two monoterpenoid lactones, loliolide (1) and epi-loliolide (2), were isolated from the crude dichloromethane extract of a microalga, Thalassiosira sp.). The structures of loliolide (1) and epi-loliolide (2) were elucidated by 1D and 2D NMR analysis, as well as a comparison of their 1H or/and 13C NMR data with those reported in the literature. In the case of loliolide (1), the absolute configurations of its stereogenic carbons were confirmed by X-ray analysis, whereas those of epi-loliolide (2) were determined by NOESY correlations. Loliolide (1) and epi-loliolide (2) were tested for their growth inhibitory activity against two Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and two Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bacteria, as well as one clinical isolate (E. coli SA/2, an extended-spectrum β-lactamase producer-ESBL) and two environmental isolates, S. aureus 74/24, a methicillin-resistant (MRSA), and E. faecalis B3/101, a vancomycin-resistant (VRE) isolates. The results showed that none of the tested compounds exhibited antibacterial activity at the highest concentrations tested (325 μM), and both revealed low antioxidant activity, with ORAC values of 2.786 ± 0.070 and 2.520 ± 0.319 µmol TE/100 mg for loliolide (1) and epi-loliolide (2), respectively.

Metabolomic profiles and differential metabolites of volatile components in Citrus aurantium Changshan-huyou pericarp during different growth and development stages

Citrus fruits possess a distinctive aroma and flavor, with Citrus aurantium Changshan-huyou (CACH) standing out due to their considerable edible and medicinal value. However, the volatile components (VOCs) in the CACH pericarp (CP) remain underexplored. In this study, gas chromatography-mass spectrometry (GC-MS) was utilized to qualitatively analyze VOCs in 27 CP samples across different growth stages. A total of 544 VOCs were identified, including 91 terpenoids. The types, quantities and distributions of VOCs were conducted. Detailed discussions on the major terpenoids in CP were also presented. A metabolomics approach combining multivariate statistical analysis with univariate analysis was employed for screening the differential metabolites. The study provides comprehensive insights into the VOCs in CP and citrus plants. Moreover, it delivers the first in-depth analysis of differential metabolites in CP throughout the entire CACH growth and development process, laying a foundation for ongoing research and development of the VOCs in CP.

Impact of plant monoterpenes on insect pest management and insect-associated microbes

The fight against insect pests primarily relies on the utilization of synthetic insecticides. However, improper application of these chemicals can lead to detrimental effects on both the environment and human health, as well as foster the development of insect resistance. Consequently, novel strategies must be implemented to address the challenges stemming from the prolonged use of synthetic insecticides in agricultural and public health environments. Certain strategies involve the combination of crop protectants, which not only enhance insecticidal effectiveness but also reduce application rates. Plant-based natural products emerge as promising alternatives for insect management. Monoterpenes, which are abundant plant compounds produced through the activation of various enzymes, have attracted significant attention for their effectiveness in insect control. Notably, they are prolific in fragrance-producing plants. This review explores the plant defense, insecticidal, and antimicrobial characteristics of monoterpenes against insect pests, shedding light on their potential modes of action and possibilities for commercialization. Emphasizing their role as targeted and environmentally safer, the review highlights the practical viability of monoterpenes within integrated pest management programs.

Terpenoid-Based High-Performance Polyester with Tacticity-Independent Crystallinity and Chemical Circularity

The development of chemically circular, bio-based polymers is an urgently needed solution to combat the plastic waste crisis. However, the most prominent, commercially implemented bio-based aliphatic polyester, poly(lactic acid) (PLA), is brittle, therefore largely limiting its broad applications. Herein, we introduce a class of aliphatic polyesters produced through the ring-opening polymerization (ROP) of (1R,5S)-8,8-dimethyl-3-oxabicyclo[3.2.1]octan-2-one (D-CamL) and the racemic mixture (rac-CamL), which exhibit superior materials properties relative to PLA. A metal-based or organic catalyst was used for the modulation of polymer tacticity. Notably, regardless of tacticity, poly(CamL) exhibits intrinsic crystallinity resulting in polyesters with high yield stress (24-39 MPa), high Young's modulus (1.36-2.00 GPa), tunable fracture strains (6-218%), and high melting temperatures (161-225 °C). Importantly, poly(CamL) can be chemically recycled to monomer in high yield and the virgin-quality poly(CamL) was obtained after repolymerization. Overall, poly(CamL) represents a new class of bio-derived and chemically circular high-performance polyesters.

Antibiofilm and Antimicrobial Potentials of Novel Synthesized Sulfur Camphor Derivatives

The question being posed by scientists around the world is how different chemical modifications of naturally occurring compounds will affect their antimicrobial properties. In the current study, sulfur derivatives of camphor containing a sulfur atom were tested to detect their antimicrobial and antibiofilm potentials. The new compounds were tested on eight Gram-positive strains (S. aureus (3 isolates), S. epidermidis (4 isolates), and E. faecalis (1 isolate)) and eight Gram-negative strains (E. coli (6 isolates), A. baumannii (1 isolate), and P. aeruginosa (1 isolate)). The ability of the strains to eradicate a biofilm was evaluated under standard stationary and flow-through conditions using the Bioflux system. Two synthesized compounds, namely rac-thiocamphor (1a) and (S, S)-(+)-thiocamphor (2a), exhibited an effect on the 24 h biofilm formed by the Gram-positive strains. Our results are an important contribution to the science of natural compounds and allow us to classify our sulfur derivatives of camphor as potential prophylactic agents in treating skin infections, antiseptics, and disinfectants. The Gram-negative strains were excluded from further stages of the tests due to their high activity (MIC ≥ 512 µg/mL). On the other hand, the compound with the strongest antimicrobial activity against the Gram-positive strains was 2a, as it led led to a reductions in cell viability of 17-52% (for MIC), 37-66% (for 2MIC), and 40-94% (for 4MIC). In addition, the experimental retention index of thiocamphor was calculated for the first time.

Biotransformation of Geraniol to Geranic Acid Using Fungus Mucor irregularis IIIMF4011

Geraniol is an important component in essential oils of aromatic plants such as lemongrass, rosa grass, and many others. It can be converted to different high-value products by using microbes/enzymes. The present study aims at the isolation and screening of microbes showing efficient production of geranic acid (a high-value product) from geraniol (a low-value monoterpene). Mucor irregularis IIIMF4011, isolated from the soil sample of Cymbopogon citratus (Lemongrass), showed biotransformation of geraniol to geranic acid. After optimization of reaction parameters, 97-100% conversion of geraniol to geranic acid was obtained after 72 h of incubation at 28 °C. Furthermore, the biotransformation reaction was also carried out in a 3 L fermentor (working volume 1.5 L), and 98.89% conversion was observed. Therefore, an efficient process of geranic acid production using M. irregularis IIIMF4011 was developed.

Pinonic Acid Derivatives Containing Thiourea Motif: Promising Antifungal Lead Compound Targeting Cellular Barrier of Colletotrichum fructicola

In order to explore novel antifungal lead compounds from plant essential oil, thirty-two pinonic acid derivatives containing thiourea groups were designed and synthesized using α-pinene as a raw material. One of these pinonic acid derivatives compound 3a exhibited noteworthy in vitro antifungal activity against Colletotrichum fructicola (EC50 = 9.22 mg/L), which was comparable to that of the positive control kresoxim-methyl (EC50 = 9.69 mg/L). Structure-activity relationship (SAR) studies demonstrated that the introduction of thiourea groups, F atoms, and Cl atoms into the structure of pinonic acid derivatives significantly improved their antifungal activity. The in vivo antifungal test revealed that compound 3a could effectively control pear anthracnose. It also proved that compound 3a showed low acute oral toxicity to honeybees (LD50 > 100 μg/bee) and low or no cytotoxicity to LO2 and HEK293 cell lines. The preliminary mechanism of action studies revealed that compound 3a caused mycelium deformity, increased cell membrane permeability, blocked the normal process of phospholipase C on the cell membrane, and reduced mycelium protein content. The results of molecular docking studies demonstrated the stable binding of compound 3a to phospholipase C and chitin synthetase. This study suggested that compound 3a could be used as a promising lead compound for the development of novel antifungal agents targeting the cellular barrier of C. fructicola.

Hydrazinated geraniol derivatives as potential broad-spectrum antiprotozoal agents

Geraniol, a primary component of several essential oils, has been associated with broad-spectrum antiprotozoal activities, although moderate to weak. This study primarily concentrated on the synthesis of hydrazinated geraniol derivatives as potential antiprotozoal agents. The synthesised compounds were tested in vitro against different parasitic protozoans of clinical relevance, including Trypanosoma brucei brucei, Trypanosoma brucei rhodesiense, Trypanosoma cruzi and Leishmania infantum. Compounds 6, 8, 13, 14 and 15 demonstrated low micromolar activity against the different parasites. Compounds 8, 13, 14 and 15 had the highest efficacy against Trypanosoma brucei rhodesiense, as indicated by their respective IC50 values of 0.74, 0.56, 1.26 and 1.00 µM. Compounds 6, 14 and 15 displayed the best activity against Trypanosoma brucei brucei, with IC50 values of 1.49, 1.48 and 1.85 µM, respectively. The activity of compounds 6, 14 and 15 also extended to intracellular Trypanosoma cruzi, with IC50 values of 5.14, 6.30 and 4.90 µM, respectively. Compound 6, with an IC50 value of 11.73 µM, and compound 14, with an IC50 value of 8.14 µM, demonstrated some modest antileishmanial activity.

Identification of Secondary Metabolites of Cyperus rotundus L. and Dose-dependent Effects on Antioxidant Activity and Carbohydrate Digestion Enzymes

Background

Cyperus rotundus L., commonly known as nutsedge or purple nutgrass, is a resilient herb in the Cyperaceae family with notable pharmacological potential due to its diverse secondary metabolites. This study aimed to identify these metabolites and evaluate the antioxidant and enzyme inhibitory activities of the crude methanol extract of C. rotundus.

Methods

The crude methanol extract of C. rotundus was prepared, and its antioxidant activity was assessed using the DPPH scavenging assay. Additionally, in vitro inhibitory effects against the enzymes: α-amylase and α-glucosidase were evaluated. The secondary metabolites present in the extract were identified using ESI-MS/MS analysis.

Results

ESI-MS/MS analysis revealed the presence of various secondary metabolites, including rutin, quercetin, β-sitosterol, limonene, and beta-pinene. The crude methanol extract exhibited strong antioxidant activity and significant inhibition of α-amylase and α-glucosidase enzymes, which play crucial roles in carbohydrate digestion.

Conclusion

The findings indicate that the crude methanol extract of C. rotundus possesses notable antioxidant properties and the potential to inhibit key enzymes involved in carbohydrate metabolism. This study enhances our understanding of the bioactive compounds in C. rotundus and suggests its therapeutic applications for managing conditions related to carbohydrate metabolism.

Where You Protonate Matters: Deciphering the Unimolecular Chemistry of Protonated Myrcene and Linalool

The unimolecular reactions of protonated myrcene and linalool were investigated by collision-induced dissociation and density functional theory calculations. Experiments on a triple quadrupole mass spectrometer showed that protonated myrcene undergoes two major unimolecular reactions losing propene and isobutene, and two minor reactions of ethene and propane loss. In each case, the product ion consists of a substituted five-member ring. Protonation of myrcene was found to form four distinct protomers, three of which can be significantly populated in the ion source. The observed fragmentation reactions were calculated and found to depend on the starting protomer. Each pathway consisted of several hydrogen-migration and ring-forming/opening steps on the way to the observed products. Likewise, protonation of linalool also produces three distinct protomers, with the global minimum being formed by protonation of a central double bond. The major reaction is water loss to form protonated myrcene, but two minor channels were also observed resulting in loss of acetone and isobutene. The calculated minimum energy reaction pathways were found to be consistent with the relative abundances of the ions in the experimental breakdown diagrams.

Thymol and carvacrol derivatives as anticancer agents; synthesis, in vitro activity, and computational analysis of biological targets

Various thymol and carvacrol derivatives have been synthesized to test the anticancer activity potential. Computational methods including network pharmacology and molecular docking approaches were utilized to identify and assess the potential biological targets relating to cancer. Amongst the synthesized derivatives the ethoxy-cyclohexyl analogues were consistently the most active against a panel of 10 different cancer cell lines covering a variety of origins. Biological target predictions revealed the AKT1 protein to be a core and central target of the most active compounds. Molecular docking identified a binding pocket within this protein in which the most active compounds bind. The incorporation of computational analysis methods and conventional structure-activity approaches identified analogues of thymol and carvacrol with the highest anticancer potential, and analyzed their possible biological targets in a comprehensive manner.

Insight into the compositional variation of volatile and polar compounds of Radix Bupleuri from different processing technologies by GC-MS and UHPLC-Q-TOF/MS metabolomics

INTRODUCTION

Insight into comparing key active ingredients of Radix Bupleuri (RB) based on different processing technologies is a key step to reveal the material basis of drug efficacy and a challenging task for developing traditional Chinese medicine (TCM).

OBJECTIVE

This work aims to establish a comprehensive comparative analysis method of TCM and its processed products, which can be used to analyze the changing trend of active components of RB before and after processing.

METHODS

First, RB was processed with rice vinegar, rice wine, and honey. Then, ultra-high-performance liquid chromatography (UHPLC) and gas chromatography (GC) coupled with mass spectrometry (MS) technology as well as multiple statistical analyses were used to comprehensively evaluate the compositional variation of polar and volatile compounds in RB under different processing processes. Meanwhile, in UHPLC-MS, a sequential window acquisition of all theoretical fragment ion spectral and information-dependent acquisition mutual authentication (SIMA) was developed.

RESULTS

A total of 30 polar components and 33 volatile components were identified as chemical markers (mainly type II saikosaponins, terpenes, and fatty acid esters). These may be the material basis for giving unique pharmacological activities to RB and its processed products.

CONCLUSIONS

These findings provided a solid foundation for the differentiated clinical application of RB, and the SIMA method held great potential for achieving accurate analysis of TCM processing ingredients.

Chemometric analysis of monoterpenes and sesquiterpenes of conifers

Volatile organic compounds (VOCs) and essential oils of conifers are widely used in the pharmaceutical industry. This work aimed to analyze the VOCs of 30 conifer species representing the Pinaceae and Cupressaceae families. Samples were collected from arboreta in Hungary, and their chemical composition was determined by gas chromatography (SPME-GC/MS); then, chemometric analyses were performed using multivariate methods to identify characteristic VOCs of conifers. Here, we present results for monoterpene and sesquiterpene profiles of the examined conifer samples. The most abundant compounds detected were α-pinene, bornyl acetate, limonene, β-pinene, β-caryophyllene, β-myrcene, δ-3-carene, and β-phellandrene. The results showed that the following volatiles were characteristic of the conifer groups: sabinene (RRT=6.0) for the cupressoid group (which includes the Cupressaceae species), longifolene (RRT=15.0) and β-pinene (RRT=6.1) were characteristic of the pinoid group (including Picea, Pinus, and Pseudotsuga species), and camphene (RRT=5.5) and bornyl acetate (RRT=12.6) were characteristic of the abietoid group (including Abies, Cedrus, and Tsuga species). Our results on VOCs in the Pinaceae and Cupressaceae families contribute to the elucidation of biodiversity patterns of conifer species and, in addition, may support the industrial application of terpenes.

Biotransformation of monoterpenes using Streptomyces strains from the rhizosphere of Inga edulis Martius from in an Amazonian urban forest fragment

To investigate the biocatalytic potential of Amazonian actinomycetes for monoterpenes biotransformation. To carry out the present study, eleven actinomycetes of the genus Streptomyces isolated from inga-cipó (Inga edulis Mart.) rhizospheres were tested for their ability to bioconvert the substrates R-(+)-limonene, S-(-)-limonene, 1S-(-)-α-pinene, and (-)-β-pinene as sole carbon and energy source. According to gas chromatography-mass spectrometry analysis, three strains, LabMicra B270, LaBMicrA B310, and LaBMicrA B314, were able to biotransform 1S-(-)-α-pinene after 96 h of growth. However, Streptomyces LaBMicrA B270 was the most promising since it converted after only 72 h all the 1S-(-)-α-pinene mainly into cis-verbenol (74.9±1.24%) and verbenone (18.2±1.20%), compounds that have important biological activities and great industrial interest as additives in foods and cosmetics. These findings can stimulate the development of natural aromas using naturally abundant monoterpenes, ratify the potential of microorganisms from almost unexplored niches such as the Amazonian rhizosphere, and reinforce the importance of preserving those niches.

Terpenes in the management of chronic kidney disease

Chronic kidney disease (CKD) is a chronic and progressive systemic condition that characterizes irreversible alterations in the kidneys' function and structure over an extended period, spanning months to years. CKD is the one of the major causes of mortality worldwide. However, very limited treatment options are available in the market for management of the CKD. Diabetes and hypertension are the key risk factors for the progression of CKD. It is majorly characterised by glomerulosclerosis, tubular atrophy, and interstitial fibrosis. Plants are considered safe and effective in treating various chronic conditions. A diverse group of phytoconstituents, including polyphenols, flavonoids, alkaloids, tannins, saponins, and terpenes, have found significant benefits in managing chronic ailments. Terpenes constitute a diverse group of plant compounds with various therapeutic benefits. Evidence-based pharmacological studies underscore the crucial role played by terpenes in preventing and managing CKD. These substances demonstrate the capacity to hinder detrimental pathways, such as oxidative stress, inflammation and fibrosis, thereby demonstrating benefit in renal dysfunction. This review offers a comprehensive overview of the roles and positive attributes of commonly occurring terpenes in managing the causes and risk factors of CKD and the associated conditions.

The genome of Vicia sativa ssp. amphicarpa provides insights into the role of terpenoids in antimicrobial resistance within subterranean fruits

Vicia sativa ssp. amphicarpa is a unique forage crop capable of simultaneously producing fruits above and below ground, representing a typical amphicarpic plant. In this study, we sequenced and assembled seven pseudo-chromosomes of the genome of V. sativa ssp. amphicarpa (n = 7) yielding a genome size of 1.59 Gb, with a total annotation of 48 932 protein-coding genes. Long terminal repeat (LTR) elements constituted 62.28% of the genome, significantly contributing to the expansion of genome size. Phylogenetic analysis revealed that the divergence between V. sativa ssp. amphicarpa and V. sativa was around 0.88 million years ago (MYA). Comparative transcriptomic and metabolomic analysis of aerial and subterranean pod shells showed biosynthesis of terpenoids in the subterranean pod shells indicating a correlation between the antimicrobial activity of subterranean pod shells and the biosynthesis of terpenoids. Furthermore, functional validation indicates that overexpression of VsTPS5 and VsTPS16 enhances terpenoid biosynthesis for antibacterial activity. Metabolomic analysis suggests the involvement of terpenoids in the antimicrobial properties of subterranean pod shells. Deciphering the genome of V. sativa ssp. amphicarpa elucidated the molecular mechanisms behind the antimicrobial properties of subterranean fruits in amphicarpic plants, providing valuable insights for the study of amphicarpic plant biology.

Exploration of selected monoterpenes as potential TRPC channel family modulator in lung cancer, an in-silico upshot

Lung cancer is still the most frequent cause of cancer-related death, accounting for nearly two million cases yearly. As cancer is a multifactorial disease, developing novel molecular therapeutics that can simultaneously target multiple associated cellular processes has become necessary. Ion channels are diverse regulators of cancer-related processes such as abnormal proliferation, invasion, migration, tumor progression, inhibition of apoptosis, and chemoresistance. Among the various families of ion channels, the transient receptor potential canonical channel family steps out in the context of lung cancer, as several members have been postulated as prognostic markers for lung cancer. Phytochemicals have been found to have health benefits in the treatment of a variety of diseases and disorders. Among phytochemicals, monoterpenes are effective in treating both the early and late stages of cancer. The molecular docking interaction analysis was conducted to evaluate the binding potential of selected monoterpenes with TRPC3, TRPC4, TRPC5, and TRPC6 involved in different phases of carcinogenesis. Amongst the selected monoterpenes, thymoquinone exhibited the highest binding energy of -6.7 kcal/mol against the TRPC4 channel, and all amino acid binding residues were similar to those of the known inhibitor for TRPC4. In addition, molecular-dynamic simulation results parameters, such as RMSD, RMSF, and Rg, indicated that thymoquinone did not impact the protein compactness and exhibited stability during the interaction. The average interaction energy between thymoquinone and TRPC4 protein was -26.85 kJ/mol. In-silico Drug-likeness and ADMET profiling indicated that thymoquinone is a druggable candidate with minimal toxicity. We propose further investigation and evaluation of thymoquinone for lead optimization and drug development.Communicated by Ramaswamy H. Sarma.

Unusual Cascade Reactions of 8-Acetoxy-6-hydroxymethyllimonene with Salicylic Aldehydes: Diverse Oxygen Heterocycles from Common Precursors

Chiral oxygen-containing heterocyclic compounds are of great interest for the development of pharmaceuticals. Monoterpenes and their derivatives are naturally abundant precursors of novel synthetic chiral oxygen-containing heterocyclic compounds. In this study, acid catalyzed reactions of salicylic aldehydes with (-)-8-acetoxy-6-hydroxymethyllimonene, readily accessible from α-pinene, leads to the formation of chiral polycyclic products of various structural types. Three of the six isolated chiral heterocyclic products obtained from salicylic aldehyde contain previously unknown polycyclic ring types. Having carried out the reaction in the presence of Brønsted or Lewis acids (Amberlyst 15, trifluoromethanesulfonic acid, trifluoroacetic acid and boron trifluoride etherate) or aluminosilicates (montmorillonite K10, halloysite nanotubes), we found that the nature of products depends on the catalyst as well as the reaction conditions (reaction time, reactant ratio, presence or absence of solvent). Detailed mechanistic insight on the complex cascade reactions for product formation is provided with extensive experimental and quantum mechanical computational studies.

The relationship between serum monoterpene levels and bone health: a retrospective cross-sectional analysis from the National Health and Nutrition Examination Survey (NHANES) data

Introduction

Monoterpenes, a subset of the terpene family composed of two isoprene units, have garnered significant attention in research circles owing to their potential medicinal benefits. Recent experimental studies indicate that they might exert positive effects on bone health. Nevertheless, the impact of monoterpenes exposure on bone health remains unexplored in humans.

Methods

We examined 748 adults (age ≥ 40 years) from the National Health and Nutrition Examination Survey (NHANES) 2013-2014 to explore the correlation between three monoterpenes (α-pinene, β-pinene, and limonene), bone mineral density (BMD) in the total lumbar spine and proximal femur, FRAX® scores, and prior bone fracture history.

Results and discussion

Our analysis unveiled a significant inverse association between a one-unit increase in the natural logarithm (ln) of α-pinene and limonene and total proximal femur BMD (ß = -0.027, S.E. = 0.008, P = 0.004 and ß = -0.019, S.E. = 0.007, P = 0.016, respectively). As serum α-pinene levels ascended across quintiles, there was a notable decrease in total proximal femur BMD (P for trend = 0.025). The inverse relationship between ln α-pinene levels and total proximal femur BMD was more pronounced in women, especially pre-menopausal women. Compared to subjects with α-pinene and limonene levels at or below the 50th percentiles, those exceeding this threshold exhibited the lowest mean value of total proximal femur BMD (0.8628 g/cm2, S.E. = 0.026, P = 0.009). However, the trend was not statistically significant (P = 0.070). Additionally, all three monoterpenes were linked to a higher prevalence of previous spine fractures, whereas β-pinene showed a reduced incidence of other types of fractures. In this comprehensive survey of American adults aged 40 and above, higher serum levels of α-pinene and limonene correlated with decreased total proximal femur BMD. Furthermore, our findings suggest a potential combined effect of α-pinene and limonene on total proximal femur BMD. Further investigation is essential to elucidate the clinical relevance and causative nature of our findings.

Exploring the effects of supplementing monoterpenoids in Moringa oleifera based-diet in Oreochromis niloticus: Improving the growth performance, feed efficiency, digestibility and body composition

Monoterpenoids are interesting hydrocarbons typically found in essential oils and have a significant role in medicinal and biological purposes. The goal of this study was to investigate the effects of two monoterpenoids, carvacrol (CAR) and menthol (MEN), supplemented with Moringa oleifera leaf meal (MOLM) based diets on growth parameters, digestibility and body composition of Nile tilapia (Oreochromis niloticus). Alongside the basal diet (control-T1), nine experimental diets supplemented with categorized levels of CAR and MEN at 200, 300 and 400 mg/kg individually and their mixtures (MIX) (1:1) (CAR-T2, 200; T3, 300; T4, 400 mg/kg, MEN-T5, 200; T6, 300; T7, 400 mg/kg and MIX- (1:1) T8, 200; T9, 300; T10, 400 mg/kg) were fed to the fingerlings (6.55 ± 0.03 g) for the period of 60 days. Monoterpenoids supplementation led to significantly (p<0.05) better growth, feed utilization and nutrient digestibility in comparison to the control group. The highest growth, feed efficiency and nutrient digestibility were noticed in fishes fed with a diet supplemented with 200 mg/kg MIX. Interestingly, fishes fed with diets containing monoterpenoids had significantly higher levels of protein and ash, but with lower lipid in comparison to the control group. Conclusively, the dietary supplements like CAR and MEN improved the health status of Nile tilapia when given either individually or in a mixture,. Specifically, the MIX at 200 mg/kg was the optimal supplementation for the fishes.

The Antiviral Potential of Perilla frutescens: Advances and Perspectives

Viruses pose a significant threat to human health, causing widespread diseases and impacting the global economy. Perilla frutescens, a traditional medicine and food homologous plant, is well known for its antiviral properties. This systematic review examines the antiviral potential of Perilla frutescens, including its antiviral activity, chemical structure and pharmacological parameters. Utilizing bioinformatics analysis, we revealed the correlation between Perilla frutescens and antiviral activity, identified overlaps between Perilla frutescens target genes and virus-related genes, and explored related signaling pathways. Moreover, a classified summary of the active components of Perilla frutescens, focusing on compounds associated with antiviral activity, provides important clues for optimizing the antiviral drug development of Perilla frutescens. Our findings indicate that Perilla frutescens showed a strong antiviral effect, and its active ingredients can effectively inhibit the replication and spread of a variety of viruses in this review. The antiviral mechanisms of Perilla frutescens may involve several pathways, including enhanced immune function, modulation of inflammatory responses, and inhibition of key enzyme activities such as viral replicase. These results underscore the potential antiviral application of Perilla frutescens as a natural plant and provide important implications for the development of new antiviral drugs.

Phytochemistry and Biological Profile of the Chinese Endemic Herb Genus Notopterygium

Notopterygium, a plant genus belonging to the Apiaceae family, is utilized in traditional Chinese medicine for its medicinal properties. Specifically, the roots and rhizomes of these plants are employed in phytotherapy to alleviate inflammatory conditions and headaches. This review provides a concise overview of the existing information regarding the botanical description, phytochemistry, pharmacology, and molecular mechanisms of the two Notopterygium species: Notopterygium incisum and N. franchetii. More than 500 distinct compounds have been derived from these plants, with the root being the primary source. These components include volatile oils, coumarins, enynes, sesquiterpenes, organic acids and esters, flavonoids, and various other compounds. Research suggests that Notopterygium incisum and N. franchetii exhibit a diverse array of pharmacological effects, encompassing antipyretic, analgesic, anti-inflammatory, antiarrhythmic, anticoagulant, antibacterial, antioxidant, and anticancer properties on various organs such as the brain, heart, digestive system, and respiratory system. Building activity screening models based on the pharmacological effects of Notopterygium species, as well as discovering and studying the pharmacological mechanisms of novel active ingredients, will constitute the primary development focus of Notopterygium medicinal research in the future.

The Volatile Compounds Composition of Different Parts of Wild Kazakhstan Sedum ewersii Ledeb

The chemical composition of Sedum ewersii Ledeb., a plant indigenous to Kazakhstan and traditionally utilized in folk medicine, was comprehensively investigated, with a focus on its various plant parts. Fresh samples collected in May 2023 from the Almaty region underwent hydrodistillation to extract volatile components, followed by analysis using gas chromatography coupled with mass spectrometric detection, which identified a total of 71 compounds across different plant parts, including the root (underground part), root (aerial part), leaf, stem, and flowering aerial part. The predominant biologically active compound identified across all plant parts was Ethyl α-D-glucopyranoside. Monoterpenes, recognized as primary secondary metabolites, were notably abundant in each plant part, with varying compositions: the root (underground part) contained 28.58% aliphatic monoterpenes, 54.41% oxygenated monoterpenoids, 1.42% diterpenoids, and 15.59% other compounds; the root (aerial part) exhibited 1.34% aliphatic monoterpenes, 31.28% oxygenated monoterpenoids, 6.16% diterpenoids, and 61.22% other compounds; the stem and leaves showed 3.06% aliphatic monoterpenes, 21.49% oxygenated monoterpenoids, 17.99% diterpenoids, and 57.46% other compounds; and the flowering aerial part displayed 8.20% aliphatic monoterpenes, 53.18% oxygenated monoterpenoids, 23.75% diterpenoids, and 14.87% other compounds. Diterpenes, particularly Phytol, were prominently present in the leaf, stem, and flowering aerial parts. Additionally, a diverse array of organic acids, ketones, and phenolic compounds were identified across the plant parts, each potentially offering distinct pharmacological benefits. The presence of exclusive compounds in specific plant parts, such as Dihydroxyacetone in the root (aerial part), underscored the pharmacological diversity of S. ewersii. This study provides valuable insights into the chemical diversity and pharmacological potential of S. ewersii, suggesting promising applications in pharmaceutical and medicinal fields. Further research aimed at elucidating the individual and synergistic pharmacological effects of these compounds is crucial to fully harness the therapeutic benefits of this plant.

Sequential Separation of Essential Oil Components during Hydrodistillation of Fresh Foliage from Azorean Cryptomeria japonica (Cupressaceae): Effects on Antibacterial, Antifungal, and Free Radical Scavenging Activities

Cryptomeria japonica wood industry generates large amounts of foliage biomass residues. Due to the increasing applications and markets for essential oils (EOs), fresh Azorean C. japonica foliage (Az-CJF) residues are used for local EO production. Hydrodistillation (HD), a common process for obtaining EOs, also provides the possibility to fractionate them. Thus, this study evaluated the in vitro antimicrobial and antioxidant activities of six Az-CJF EO fractions (Frs. 1-6), collected at sequential HD timeframes (HDTs: 0-2, 2-10, 10-30, 30-60, 60-120, and 120-240 min), in comparison to the crude EO, obtained from a non-fractionated HD (0-240 min HDT). Antimicrobial activities were assessed via disc diffusion method against seven bacteria (foodborne and/or human pathogens) and two Penicillium spp. (phytopathogenic fungi), and antioxidant activity was estimated using DPPH and ABTS assays. Concerning the antibacterial activity, all the EO samples were effective only toward Gram-positive bacteria. Fractions 1-3 (<30 min HDT) were the most active, with growth inhibition zones (GIZ) of 7.0-23.3 mm (1.4-2.2 times higher than those of the crude EO), being Bacillus spp. (B. licheniformis and B. subtilis) the most sensitive, followed by Staphylococcus aureus and Micrococcus luteus. Regarding the antifungal activity, Frs. 1-3 also displayed the best activities, but only against P. italicum (GIZ around 9.0 mm), while the crude EO showed no antifungal activity. Overall, the best antimicrobial properties of Frs. 1-3 could be attributed, at least in part, to their highest content in α-pinene and bornyl acetate. On the other hand, Frs. 4-6 (>30 min HDT) exhibited the strongest antioxidant activities (EC50 values: 1.5-2.3 and 1.0-1.7 mg mL-1 for DPPH and ABTS, respectively), being at least 1.3-fold higher than those of the crude EO. The presence of nezukol, elemol, and eudesmol isomers could strongly contribute to the best free radical scavenging properties of Frs. 4-6. In conclusion, HD was found to be an efficient process for obtaining new Az-CJF EO fractions with variable and enhanced bioactivities due to their differential composition, as assessed using GC-MS. Hence, these findings could contribute to increasing the commercial potential of the C. japonica EO industry, namely, the Fr2 and Fr6, which presented the most significant activities and can have potential applications in the food, medical, and agriculture sectors.

Carvacrol and Thymol Hybrids: Potential Anticancer and Antibacterial Therapeutics

Cancer is ranked among lethal diseases globally, and the increasing number of cancer cases and deaths results from limited access to effective therapeutics. The use of plant-based medicine has been gaining interest from several researchers. Carvacrol and its isomeric compound, thymol, are plant-based extracts that possess several biological activities, such as antimalarial, anticancer, antifungal, and antibacterial. However, their efficacy is compromised by their poor bioavailability. Thus, medicinal scientists have explored the synthesis of hybrid compounds containing their pharmacophores to enhance their therapeutic efficacy and improve their bioavailability. Hence, this review is a comprehensive report on hybrid compounds containing carvacrol and its isomer, thymol, with potent anticancer and antibacterial agents reported between 2020 and 2024. Furthermore, their structural activity relationship (SAR) and recommended future strategies to further enhance their therapeutic effects will be discussed.

Covalent modification of γ-cyclodextrin with geraniol: An antibacterial agent with good thermal stability, solubility and biocompatibility

Geraniol (Ger) is an essential oil molecule with excellent biological activity. High hydrophobicity and volatility limit its practical application. Cyclodextrins (CDs) are water-soluble cyclic oligosaccharides with hydrophobic cavities. Physical encapsulation of CDs to improve the solubility and stability of essential oil molecules is not satisfactory. Therefore, this study synthesized the γ-CD derivative (γ-CD-Ger) by grafting Ger onto γ-CD using a bromide-mediated method. Compared to the inclusion complexes (γ-CD/Ger) formed by both, the derivatives exhibit better solubility and thermal stability. The derivative has better antibacterial activity when the ratio of γ-CD to Ger was 1:2. In addition, the derivatives did not exhibit cytotoxic and hemolytic properties. These results indicate that this research provides a water-soluble antibacterial agent with a wide range of promising applications and offers new ideas for the application of alcohol hydrophobic molecules in aqueous systems.

Thymol, a Monoterpenoid within Polymeric Iodophor Formulations and Their Antimicrobial Activities

Antimicrobial resistance (AMR) poses an emanating threat to humanity's future. The effectiveness of commonly used antibiotics against microbial infections is declining at an alarming rate. As a result, morbidity and mortality rates are soaring, particularly among immunocompromised populations. Exploring alternative solutions, such as medicinal plants and iodine, shows promise in combating resistant pathogens. Such antimicrobials could effectively inhibit microbial proliferation through synergistic combinations. In our study, we prepared a formulation consisting of Aloe barbadensis Miller (AV), Thymol, iodine (I2), and polyvinylpyrrolidone (PVP). Various analytical methods including SEM/EDS, UV-vis, Raman, FTIR, and XRD were carried out to verify the purity, composition, and morphology of AV-PVP-Thymol-I2. We evaluated the inhibitory effects of this formulation against 10 selected reference strains using impregnated sterile discs, surgical sutures, gauze bandages, surgical face masks, and KN95 masks. The antimicrobial properties of AV-PVP-Thymol-I2 were assessed through disc diffusion methods against 10 reference strains in comparison with two common antibiotics. The 25-month-old formulation exhibited slightly lower inhibitory zones, indicating changes in the sustained-iodine-release reservoir. Our findings confirm AV-PVP-Thymol-I2 as a potent antifungal and antibacterial agent against the reference strains, demonstrating particularly strong inhibitory action on surgical sutures, cotton bandages, and face masks. These results enable the potential use of the formulation AV-PVP-Thymol-I2 as a promising antimicrobial agent against wound infections and as a spray-on contact-killing agent.

Potential of natural products in inflammation: biological activities, structure-activity relationships, and mechanistic targets

A balance between the development and suppression of inflammation can always be found in the body. When this balance is disturbed, a strong inflammatory response can damage the body. It sometimes is necessary to use drugs with a significant anti-inflammatory effect, such as nonsteroidal anti-inflammatory drugs and steroid hormones, to control inflammation in the body. However, the existing anti-inflammatory drugs have many adverse effects, which can be deadly in severe cases, making research into new safer and more effective anti-inflammatory drugs necessary. Currently, numerous types of natural products with anti-inflammatory activity and distinct structural features are available, and these natural products have great potential for the development of novel anti-inflammatory drugs. This review summarizes 260 natural products and their derivatives with anti-inflammatory activities in the last two decades, classified by their active ingredients, and focuses on their structure-activity relationships in anti-inflammation to lay the foundation for subsequent new drug development. We also elucidate the mechanisms and pathways of natural products that exert anti-inflammatory effects via network pharmacology predictions, providing direction for identifying subsequent targets of anti-inflammatory natural products.

A facile one step route that introduces functionality to polymer powders for laser sintering

Laser Sintering (LS) is a type of Additive Manufacturing (AM) exploiting laser processing of polymeric particles to produce 3D objects. Because of its ease of processability and thermo-physical properties, polyamide-12 (PA-12) represents ~95% of the polymeric materials used in LS. This constrains the functionality of the items produced, including limited available colours. Moreover, PA-12 objects tend to biofoul in wet environments. Therefore, a key challenge is to develop an inexpensive route to introduce desirable functionality to PA-12. We report a facile, clean, and scalable approach to modification of PA-12, exploiting supercritical carbon dioxide (scCO2) and free radical polymerizations to yield functionalised PA-12 materials. These can be easily printed using commercial apparatus. We demonstrate the potential by creating coloured PA-12 materials and show that the same approach can be utilized to create anti-biofouling objects. Our approach to functionalise materials could open significant new applications for AM.

Myrtenal exhibits cardioprotective effects by attenuating the pathological progression associated with myocardial infarction

BACKGROUND

Myocardial infarction poses major risks to human health because of their incredibly high rates of morbidity and mortality. Infarctions are more likely to develop as a result of dysregulation of cell death. Myrtenal can be considered for their bioactive beneficial activity in the context of cardiovascular pathologies and, particularly, in the protection toward oxidative stress followed by ischemic injury.

OBJECTIVE

This study aimed to put limelight on the antioxidant, anti-apoptotic, and antibacterial properties of Myrtenal.

METHODS

An in vitro model of oxidative stress-induced injury was entrenched in H9c2 cells using hydrogen peroxide, and the effects of Myrtenal were investigated. The MTT, cellular enzyme level, staining, and flow cytometry analysis were used to examine protective, antioxidant, and anti-apoptotic effects. The gene expressions were detected by qPCR. Antibacterial effect and biofilm formation were also done.

RESULT

The findings revealed that Myrtenal alone had negligible cytotoxic effects and that Myrtenal protects H9c2 against H2 O2 -induced cell death at micromolar concentrations. Myrtenal pre-treatment inhibited the generation of reactive oxygen species (ROS) as well as remarkably decreased the fluorescence intensity of ROS. Additionally, Myrtenal considerably increased the synthesis of antioxidant enzymes while dramatically decreasing the production of MDA and LDH. qPCR demonstrated the downregulation of Cas-9, TNF-α, NF-κB, P53, BAX, iNOS, and IL-6 expression while an upregulation of Bcl-2 expression in Myrtenal pre-treated groups. Myrtenal also holds the magnificent property of inhibiting bacterial growth.

CONCLUSION

Myrtenal ameliorates H2 O2 -induced cardiomyocyte injury and protects cardiomyocyte by inhibiting oxidative stress, inflammation, and apoptosis and may be a promise drug for the treatment of heart diseases.

Antiproliferative in Vitro Evaluation of Terpenic Amines Synthesized via a Rhodium-catalyzed Hydroaminomethylation

Terpene-derived alkaloids show a variety of biological activities, including antioxidant, anti-inflammatory, antimicrobial and cytotoxicity effects. In this work, homologated monoterpene amines have been prepared via a rhodium-catalyzed hydroaminomethylation of biomass-based alkenes, such as (R)-limonene, linalool, myrcene and camphene, in combination with secondary amines of aliphatic and aromatic nature, namely morpholine and N-methylaniline, leading to highly chemo- and regioselective processes. The as-prepared amines were obtained in 50-99 % overall yields, and in vitro tested on a human colon cancer cell line (HCT-116) to evaluate their cytotoxic potential. The lead compound of the series (3 a) showed cytotoxicity in the micromolar range (IC50 52.46 μM) via the induction of cell death by apoptosis, paving the way towards further structure-activity relationship studies.

The behavioral sensitivity of mice to acyclic, monocyclic, and bicyclic monoterpenes

Monoterpenes are a large class of naturally occurring fragrant molecules. These chemicals are commonly used in olfactory studies to survey neural activity and probe the behavioral limits of odor discrimination. Monoterpenes (typically in the form of essential oils) have been used for centuries for therapeutic purposes and have pivotal roles in various biological and medical applications. Despite their importance for multiple lines of research using rodent models and the role of the olfactory system in detecting these volatile chemicals, the murine sensitivity to monoterpenes remains mostly unexplored. We assayed the ability of C57BL/6J mice to detect nine different monoterpenes (the acyclic monoterpenes: geraniol, citral, and linalool; the monocyclic monoterpenes: r-limonene, s-limonene, and γ-terpinene; and the bicyclic monoterpenes: eucalyptol, α-pinene, and β-pinene) using a head-fixed Go / No-Go operant conditioning assay. We found that mice can reliably detect monoterpene concentrations in the low parts per billion (ppb) range. Specifically, mice were most sensitive to geraniol (threshold: 0.7 ppb) and least sensitive to γ-terpinene (threshold: 18.1 ppb). These estimations of sensitivity serve to set the lower limit of relevant monoterpene concentrations for functional experiments in mice. To define an upper limit, we estimated the maximum concentrations that a mouse may experience in nature by collating published headspace analyses of monoterpene concentrations emitted from natural sources. We found that natural monoterpenes concentrations typically ranged from ~1 to 1000 ppb. It is our hope that this dataset will help researchers use appropriate monoterpene concentrations for functional studies and provide context for the vapor-phase delivery of these chemicals in studies investigating their biological activity in mice.

Ability of Selected Monoterpenes to Reduce Fe(III) Ions Being Pro-Neurodegenerative Factors: Tests Based on a FRAP Reaction Extended to 48 Hours

Monoterpenes are secondary plant metabolites, and such volatile compounds have antioxidant, antibacterial, antiviral, and enzyme inhibitory properties. These compounds are also able to reduce the potentially pro-neurodegenerative trace metal ions that can be sources of free radicals. One basic method used to evaluate the ability of chemical compounds to reduce Fe(III) is FRAP. To date, most studies based on a FRAP assay were performed within several dozen minutes. However, taking into account the diversity of compounds, it is justified to observe their activity over a much longer period of time. The present study aimed to observe the activity of isopulegol, γ-terpinene, α-terpinene, linalool, carvone, citral, and α-phellandrene over a 48 h period. Our study indicates that the lengthened reaction period enhanced activity from several dozen to several hundred percent. The obtained results also revealed an explicit high correlation of the increase in the activity of compounds with the increase in monoterpene concentration. Due to the hydrophobic character of monoterpenes, the FRAP method was modified by the addition of Tween 20. The highest activity was obtained for α-terpinene and γ-terpinene.

Plant Monoterpenes and Essential Oils as Potential Anti-Ageing Agents: Insights from Preclinical Data

Ageing is a natural process characterized by a time-dependent decline of physiological integrity that compromises functionality and inevitably leads to death. This decline is also quite relevant in major human pathologies, being a primary risk factor in neurodegenerative diseases, metabolic disorders, cardiovascular diseases and musculoskeletal disorders. Bearing this in mind, it is not surprising that research aiming at improving human health during this process has burst in the last decades. Importantly, major hallmarks of the ageing process and phenotype have been identified, this knowledge being quite relevant for future studies towards the identification of putative pharmaceutical targets, enabling the development of preventive/therapeutic strategies to improve health and longevity. In this context, aromatic plants have emerged as a source of potential bioactive volatile molecules, mainly monoterpenes, with many studies referring to their anti-ageing potential. Nevertheless, an integrated review on the current knowledge is lacking, with several research approaches studying isolated ageing hallmarks or referring to an overall anti-ageing effect, without depicting possible mechanisms of action. Herein, we aim to provide an updated systematization of the bioactive potential of volatile monoterpenes on recently proposed ageing hallmarks, and highlight the main mechanisms of action already identified, as well as possible chemical entity-activity relations. By gathering and categorizing the available scattered information, we also aim to identify important research gaps that could help pave the way for future research in the field.

In-silico molecular modelling studies of some camphor imine based compounds as anti-influenza A (H1N1) pdm09 virus agents

The advent of influenza A (H1N1) drug-resistant strains led to the search quest for more potent inhibitors of the influenza A virus, especially in this devastating COVID-19 pandemic era. Hence, the present research utilized some molecular modelling strategies to unveil new camphor imine-based compounds as anti-influenza A (H1N1) pdm09 agents. The 2D-QSAR results revealed GFA-MLR (R2train = 0.9158, Q2=0.8475) and GFA-ANN (R2train = 0.9264, Q2=0.9238) models for the anti-influenza A (H1N1) pdm09 activity prediction which have passed the QSAR model acceptability thresholds. The results from the 3D-QSAR studies also revealed CoMFA (R2train =0.977, Q2=0.509) and CoMSIA_S (R2train =0.976, Q2=0.527) models for activity predictions. Based on the notable information derived from the 2D-QSAR, 3D-QSAR, and docking analysis, ten (10) new camphor imine-based compounds (22a-22j) were designed using the most active compound 22 as the template. Furthermore, the high predicted activity and binding scores of compound 22j were further justified by the high reactive sites shown in the electrostatic potential maps and other quantum chemical calculations. The MD simulation of 22j in the active site of the influenza hemagglutinin (HA) receptor confirmed the dynamic stability of the complex. Moreover, the appraisals of drug-likeness and ADMET properties of the proposed compounds showed zero violation of Lipinski's criteria with good pharmacokinetic profiles. Hence, the outcomes in this work recommend further in-depth in vivo and in-vitro investigations to validate these theoretical findings.Communicated by Ramaswamy H. Sarma.

Evaluation of the anti-inflammatory and antioxidant properties and isolation and characterization of a new bioactive compound, 3,4,9-trimethyl-7-propyldecanoic acid from Vitex negundo

ETHNOPHARMACOLOGICAL RELEVANCE

Herbal medicines derived from plant extraction are affordable, more therapeutically effective, and have fewer side effects than contemporary medications. Vitex negundo L. (V. negundo). is a medicinal shrub, which contains numerous phytoconstituents. In ancient medicinal practices, V. negundo was primarily prescribed as an analgesic and anti-inflammatory drug.

AIM OF THE STUDY

This study aims to evaluate the anti-inflammatory and antioxidant characteristics of crude extracts from V. negundo leaves, including those derived from petroleum ether (P), methanol (M), and aqueous (A) solvents. Additionally, the research seeks to identify the specific bioactive compounds responsible for these observed properties.

MATERIALS AND METHODS

The nitric oxide scavenging study was performed to evaluate the V. negundo crude extract's ability to function as a nitric oxide scavenger. Protein denaturation and proteinase inhibition experiments were employed to study the ability of extracts to suppress proteolysis and inhibit the enzymes that cause tissue injury. The membrane-stabilizing potency of plant extracts were examined through the process of heat-induced hemolysis. The ability of the extracts to neutralize free radicals showed a dose-dependent response, and the aqueous extract exhibited substantially higher activity in both FRAP and DPPH. The GC-MS analysis of V. negundo extracts revealed a vast array of pharmacologically active metabolites. Based on this Bioassay-guided fractionation approach, the optimal extract was selected for the potent molecule isolation and characterization.

RESULTS

The findings demonstrated that the aqueous extract of V. negundo exhibited markedly superior radical scavenging and anti-inflammatory capabilities compared to the other two extracts. Furthermore, a new molecule, 3,4,9-trimethyl-7-propyldecanoic acid was isolated from this extract, and its chemical structure was successfully determined.

CONCLUSION

This study revealed that the aqueous extract of V. negundo demonstrated notably stronger in vitro anti-inflammatory and antioxidant properties in comparison to the methanol and petroleum ether extracts. The identified active compound, 3,4,9-trimethyl-7-propyldecanoic acid is likely responsible for the extract's free radical scavenging and anti-inflammatory effects. Furthermore, conducting both in vitro and in vivo studies is crucial to substantiate the potential of this active constituent for the development of an anti-inflammatory drug derived from V. negundo.

Green Synthesized Polymeric Iodophors with Thyme as Antimicrobial Agents

Antimicrobial resistance (AMR) is a growing concern for the future of mankind. Common antibiotics fail in the treatment of microbial infections at an alarming rate. Morbidity and mortality rates increase, especially among immune-compromised populations. Medicinal plants and their essential oils, as well as iodine could be potential solutions against resistant pathogens. These natural antimicrobials abate microbial proliferation, especially in synergistic combinations. We performed a simple, one-pot synthesis to prepare our formulation with polyvinylpyrrolidone (PVP)-complexed iodine (I2), Thymus Vulgaris L. (Thyme), and Aloe Barbadensis Miller (AV). SEM/EDS, UV-vis, Raman, FTIR, and XRD analyses verified the purity, composition, and morphology of AV-PVP-Thyme-I2. We investigated the inhibitory action of the bio-formulation AV-PVP-Thyme-I2 against 10 selected reference pathogens on impregnated sterile discs, surgical sutures, cotton gauze bandages, surgical face masks, and KN95 masks. The antimicrobial properties of AV-PVP-Thyme-I2 were studied by disc diffusion methods and compared with those of the antibiotics gentamycin and nystatin. The results confirm AV-PVP-Thyme-I2 as a strong antifungal and antibacterial agent against the majority of the tested microorganisms with excellent results on cotton bandages and face masks. After storing AV-PVP-Thyme-I2 for 18 months, the inhibitory action was augmented compared to the fresh formulation. Consequently, we suggest AV-PVP-Thyme-I2 as an antimicrobial agent against wound infections and a spray-on contact killing agent.

Chemotaxonomy, antibacterial and antioxidant activities of selected aromatic plants from Tabuk region-KSA

Chemotaxonomy is a valuable tool for obtaining taxonomic insights, which are most effectively employed in combination with other forms of data to establish a system of classification that closely reflects natural connections. The utilization of plant secondary metabolites possessing diverse therapeutic qualities signifies the growing exploitation of natural products in the medical discipline. The objectives of the current study encompassed the identification of phytochemicals in the extracts of nine species of medicinal plants, the examination of their chemotaxonomic properties, and the assessment of the antibacterial and antioxidant capabilities exhibited by the extracts. GC-MS technology was employed for the identification of phytochemical compounds. The study utilized ClassyFire, an automated chemical classification system that incorporates an extensive and computable classification, to categorize chemicals. The chemical classification of plants was examined by the application of principal component analysis (PCA) and cluster analysis (CA). The bactericidal properties of plants were assessed against four harmful bacterial species using the disc diffusion technique. The antioxidant properties of plant extracts were assessed employing the DPPH free radical scavenging methodology, and the half maximal effective concentration (EC50) was determined using dose response models. The calculator being referred to is the Quest Graph™ EC50 Calculator. In the plant extracts, the analysis disclosed the occurrence of 160 phytochemicals, classified into 36 phytochemical classes. The results of CA and PCA demonstrated the proximity and associations among Asteraceae species, while indicating the divergence of the two Lamiaceae species. Achillea fragrantissima and Ducrosia flabellifolia demonstrated the most diversity in phytochemical classes, while Thymus vulgaris displayed the highest level of dominance. Pulicaria undulata and T. vulgaris had the most notable antibacterial activity. D. flabellifolia and P. incisa demonstrated the highest levels of antioxidant activity. Ethanol exhibited superior antibacterial efficacy compared to other solvents. The remarkable biological activities exhibited by these plant extracts can be ascribed to the copious presence of certain chemicals, predominantly sesquiterpenoids, monoterpenoids, benzene and its derivatives, naphthalenes, fatty acyls, and phenols. The susceptibility of Gram-positive bacterial species to plant extracts was shown to be higher in comparison to Gram-negative bacterial species.