Antibacterial activity of turmeric oil: a byproduct from curcumin manufacture

Nature's Arsenal: Uncovering Antibacterial Agents Against Antimicrobial Resistance

Background/Objectives: Antimicrobial resistance (AMR) poses a significant public health threat, leading to increased mortality. The World Health Organization has established a priority list highlighting critical multidrug-resistant (MDR) pathogens that demand urgent research on antimicrobial treatments. Considering this and the fact that new antibiotics are only sporadically approved, natural antibacterial agents have seen a resurgence in interest as potential alternatives to conventional antibiotics and chemotherapeutics. Natural antibacterials, derived from microorganisms, higher fungi, plants, animals, natural minerals, and food sources, offer diverse mechanisms of action against MDR pathogens. Here, we present a comprehensive summary of antibacterial agents from natural sources, including a brief history of their application and highlighting key strategies for using microorganisms (microbiopredators, such as bacteriophages), plant extracts and essential oils, minerals (e.g., silver and copper), as well as compounds of animal origin, such as milk or even venoms. The review also addresses the role of prebiotics, probiotics, and antimicrobial peptides, as well as novel formulations such as nanoparticles. The mechanisms of action of these compounds, such as terpenoids, alkaloids, and phenolic compounds, are explored alongside the challenges for their application, e.g., extraction, formulation, and pharmacokinetics. Conclusions: Future research should focus on developing eco-friendly, sustainable antimicrobial agents and validating their safety and efficacy through clinical trials. Clear regulatory frameworks are essential for integrating these agents into clinical practice. Despite challenges, natural sources offer transformative potential for combating AMR and promoting sustainable health solutions.

Controlling the drug delivery efficiency of chitosan-based systems through silver nanoparticles and oxygen plasma

Today, curcumin's therapeutic properties are used in drug delivery systems. In this work, chitosan (CS) /Montmorillonite (MMT) hydrogels were synthesized to improve the performance of curcumin molecules. According to the results, drug release characteristics of CS/MMT/curcumin highly depend on the pH of the environment and properties of Ag nanoparticles. Moreover, curcumin and Ag nanoparticles were placed under the influence of oxygen plasma. Our results indicate that oxygen plasma, as a simple, clean, and environment-friendly method, can be used as an effective method for controlling the efficiency of drug release and antibacterial characteristics of curcumin molecules in hydrogels. In this case, by increasing the exposure time of the samples under the influence of oxygen plasma, their antibacterial properties and drug release efficiency are significantly enhanced.

HOO radical scavenging activity of curcumin I and III in physiological conditions: a theoretical investigation on the influence of acid-base equilibrium and tautomerism

Curcumin possesses various effective medicinal properties, such as anti-cancer, anti-Alzheimer's, anti-inflammatory, and antioxidant effects, where its free radical scavenging activities play a crucial role in its therapeutic mechanisms. Although the antioxidant properties of curcumin and its derivatives have been previously studied, a systematic investigation of the thermodynamics and kinetics of the reaction with the hydroperoxide radical (HOO˙) - a standardized free radical - in different solvents is lacking. This study examined the HOO˙ radical scavenging activities of two curcumin derivatives, specifically curcumin I (Cur-I) and curcumin III (Cur-III), in water and pentyl ethanoate (PEA) solutions using Density Functional Theory (DFT) approaches. The antioxidant properties of the neutral and anionic forms of their tautomers, including the keto-enol and diketone forms, were explored via three standard mechanisms: hydrogen abstraction (Abs), radical addition (Add), and single electron transfer (SET). Intrinsic parameters, thermochemical parameters, and kinetics of the curcumin-HOO˙ reactions were systematically characterized. As a result, the overall rate constant for the reaction of Cur-I in the water (9.36 × 107 M-1 s-1) is approximately 3.6 times higher than that of Cur-III (2.60 × 107 M-1 s-1). Meanwhile, the rate constants in PEA solvent are less significant, being 4.02 × 101 M-1 s-1 and 8.16 × 102 M-1 s-1 for Cur-I and Cur-III, respectively. Due to the dominant molar fraction of the keto-enol form compared to the diketone, the reaction rates are primarily attributed to the keto-enol form. The SET reaction of dianionic form contributes a decisive proportion to the overall rate constants of both Cur-I and Cur-III. Finally, an analysis of the chemical nature of the Abs reactions reveals that the most predominant hydrogen transfer at the phenolic -OH groups (i.e., O22H and O23H) occurs via a proton-coupled electron transfer (PCET) mechanism.

Multi-target directed ligands inspired natural products as an effective approach for the treatment of complex chronic health disorders

Complex diseases involve multifaceted etiological components, which limit the effectiveness of conventional targeted therapies. Therefore, standard medicinal treatments often face significant challenges and failures when addressing these disease conditions. Furthermore, the growing interest in multidrug resistance (MDR), the occurrence of adverse drug reactions related to use traditional approaches, and the limited clinical efficacy of single-target drug therapy have increased the demand for innovative drug treatments. In this rapidly evolving era, the exploration of multi-target directed ligands (MTDLs) derived from natural products has granted us access to a wide range of compounds with medicinal properties. The allure of these MTDLs lies in their unique ability to minimize side effects from using two medicinal agents, establishing them as the preferred choice for drug developers. MTDLs have been recognized for their extraordinary capacity to collectively hinder multiple pathways implicated in the development of intricate diseases by merging or linking active molecules obtained from these sources. This review delves into promising MTDLs derived from natural products, which modulates diverse biological pathways implicated in complex diseased conditions particularly Alzheimer's disease, diabetes, cardiac disorders and inflammatory conditions.

Phytomedical compounds as promising therapeutic agents for COVID-19 targeting angiotensin-converting enzyme 2: a review

AIMS

The aim of the present review was to highlight natural product investigations in silico and in vitro to find plants and chemicals that inhibit or stimulate angiotensin-converting enzyme 2 (ACE-2).

BACKGROUND

The global reduction of incidents and fatalities attributable to infections with SARS-CoV-2 is one of the most public health problems. In the absence of specific therapy for coronavirus disease 2019 (COVID-19), phytocompounds generated from plant extracts may be a promising strategy worth further investigation, motivating researchers to evaluate the safety and anti-SARS-CoV-2 effectiveness of these ingredients.

OBJECTIVE

To review phytochemicals in silico for anti-SARS-CoV-2 activity and to assess their safety and effectiveness in vitro and in vivo.

METHODS

The present review was conducted using various scientific databases and studies on anti-SARS-CoV-2 phytochemicals were analyzed and summarized. The results obtained from the in silico screening were subjected to extraction, isolation, and purification. The in vitro studies on anti-SarcoV-2 were also included in this review. In addition, the results of this research were interpreted, analyzed, and documented on the basis of the bibliographic information obtained.

RESULTS

This review discusses recent research on using natural remedies to cure or prevent COVID-19 infection. The literature analysis shows that the various herbal preparations (extracts) and purified compounds can block the replication or entrance of the virus directly to carry out their anti-SARS-CoV-2 effects. It is interesting to note that certain items can prevent SARS-CoV-2 from infecting human cells by blocking the ACE-2 receptor or the serine protease TMPRRS2. Moreover, natural substances have been demonstrated to block proteins involved in the SARS-CoV-2 life cycle, such as papain- or chymotrypsin-like proteases.

CONCLUSION

The natural products may have the potential for use singly or in combination as alternative drugs to treat/prevent COVID-19 infection, including blocking or stimulating ACE-2. In addition, their structures may provide indications for the development of anti-SARS-CoV-2 drugs.

Unlocking the medicinal arsenal of Cissus assamica: GC-MS/MS, FTIR, and molecular docking insights

Background and aims

This study investigated the biochemical components present in the leaves of Cissus assamica. The primary aim was to analyze these components using advanced techniques and assess their potential therapeutic applications.

Methodology

Fourier Transform Infrared (FT-IR) spectroscopy, Gas Chromatography-Mass Spectrometry (GC-MS), and Mass Spectral analysis were employed to identify and characterize the compounds in Cissus assamica leaves. The mass spectra of each compound were compared with data from the Wiley and NIST libraries to determine their names, molecular masses, and chemical structures. FT-IR analysis identified characteristic functional groups by their specific frequencies.

Results and discussion

FT-IR spectroscopic analysis revealed significant molecular vibrations at frequencies of 3265.63, 2853.81, 1638.60, 1469.21, and 1384.95 cm⁻¹, indicating the presence of specific functional groups. The GC-MS analysis identified distinct compounds, such as "aR-Turmerone," "Curlone," "7,8-Epoxylanostan-11-ol, 3-acetoxy-," "13-Docosenamide, (Z)-," "Phenol, 3,5-bis(1,1-dimethylethyl)-," "9,19-Cyclolanostan-3-ol, 24,24-epoxymethano-, acetate," and "Quinoline-5,8-dione-6-ol, 7-[[(4-cyclohexylbutyl)amino]methyl]-." These compounds exhibited potential therapeutic applications. Their cytotoxic, antimicrobial, antidiarrheal, anti-hyperglycemic, and pain-relieving properties were evaluated by comparing them with reference ligands targeting specific receptors, including dihydrofolate reductase (DHFR), epidermal growth factor receptor (EGFR), kappa opioid receptor (KOR), glucose transporter 3 (GLUT 3), and cyclooxygenase 2 (COX-2).

Conclusion

The results of this study suggest that Cissus assamica leaves contain bioactive compounds with potential therapeutic benefits for treating infections, diarrhea, hyperglycemia, and pain. However, further research is needed to conduct comprehensive phytochemical screening and establish the precise mechanisms of action for the crude extract or the plant-derived compounds.

Curcumin's membrane localization and disruptive effects on cellular processes - insights from neuroblastoma, leukemic cells, and Langmuir monolayers

In therapies, curcumin is now commonly formulated in liposomal form, administered through injections or creams. This enhances its concentration at the cellular level compared to its natural form ingestion. Due to its hydrophobic nature, curcumin is situated in the lipid part of the membrane, thereby modifying its properties and influencing processes The aim of the research was to investigate whether the toxicity of specific concentrations of curcumin, assessed through biochemical tests for the SK-N-SH and H-60 cell lines, is related to structural changes in the membranes of these cells, caused by the localization of curcumin in their hydrophobic regions. Biochemical tests were performed using spectrophotometric methods. Langmuir technique were used to evaluate the interaction of the curcumin with the studied lipids. Direct introduction of curcumin into the membranes alters their physicochemical parameters. The extent of these changes depends on the initial properties of the membrane. In the conducted research, it has been demonstrated that curcumin may exhibit toxicity to human cells. The mechanism of this toxicity is related to its localization in cell membranes, leading to their dysfunction. The sensitivity of cells to curcumin presence depends on the saturation level of their membranes; the more rigid the membrane, the lower the concentration of curcumin causes its disruption.

Curcumin hybrid molecules for the treatment of Alzheimer's disease: Structure and pharmacological activities

Alzheimer's disease (AD) is the most common neurodegenerative disease among the elderly. Contemporary treatments can only relieve symptoms but fail to delay disease progression. Curcumin is a naturally derived compound that has demonstrated significant therapeutic effects in AD treatment. Recently, molecular hybridization has been utilized to combine the pharmacophoric groups present in curcumin with those of other AD drugs, resulting in a series of novel compounds that enhance the therapeutic efficacy through multiple mechanisms. In this review, we firstly provide a concise summary of various pathogenetic hypotheses of AD and the mechanism of action of curcumin in AD, as well as the concept of molecular hybridization. Subsequently, we focus on the recent development of hybrid molecules derived from curcumin, summarizing their structures and pharmacological activities, including cholinesterase inhibitory activity, Aβ aggregation inhibitory activity, antioxidant activity, and other activities. The structure-activity relationships were further discussed.

Immunoregulatory effects of nanocurcumin in inflammatory milieu: Focus on COVID-19

The use of natural compounds, such as curcumin, to treat infections caused by bacteria, viruses, fungi, parasites, inflammatory diseases, and various types of cancer is an active and dynamic area of research. Curcumin has a long history of use in the food industry, and there is currently a growing interest in its therapeutic applications. Numerous clinical trials have consistently shown that curcumin, a polyphenolic compound, is safe and well-tolerated even at high doses. There is no toxicity limit. However, the clinical efficacy of curcumin has been limited by its constraints. However, scientific evidence indicates that the use of adjuvants and carriers, such as nanoparticles, exosomes, micelles, and liposomes, can help overcome this limitation. The properties, functions, and human benefits of using nanocurcumin are well-supported by scientific research. Recent evidence suggests that nanocurcumin may be a beneficial therapeutic modality due to its potential to decrease gene expression and secretion of specific inflammatory biomarkers involved in the cytokinestorm seen in severe COVID-19, as well as increase lymphocyte counts. Nanocurcumin has demonstrated the ability to improve clinical manifestations and modulate immune response and inflammation in various autoinflammatory diseases. Additionally, its efficacy, affordability, and safety make it a promising replacement for residual cancer cells after tumor removal. However, further studies are necessary to evaluate the safety and efficacy of nanocurcumin as a new therapeutic in clinical trials, including appropriate dosage, frequency, and duration.

Curcumin Derivatives Linked to a Reduction of Oxidative Stress in Mental Dysfunctions and Inflammatory Disorders

Stress is a critical factor in the etiology of inflammation and neurodegeneration. The risk factor for the majority of psychiatric disorders is oxidative stress-induced depression. Mitochondrial damage and oxidative stress are associated with the development of neurodegenerative disorders. During aging, the brain and associated regions become more susceptible due to oxidative stress. The leading cause of oxidative stress is the continuous generation of ROS (reactive oxygen species) and RNS (Reactive nitrogen species) endogenously or exogenously. In this review, discussion on a potent antioxidant natural constituent "curcumin" has been made to alleviate many pathological and neurological disorders. A focused compilation of vast and informative research on the potential of curcumin as a magical moiety used therapeutically has been done in search of its role in controlling the neurological and similar disorders induced by oxidative stress.

Analysis of the antibacterial effects of turmeric on particular bacteria

Antimicrobial properties of plants have been investigated by a number of studies worldwide and many of them have been used as therapeutic alternatives because of their antimicrobial properties. The quest for suitable and affordable alternative in the face of increasing antimicrobial drug resistant has led researchers into exploring the use of plant extract in the treatment of infections. The antibacterial properties of turmeric (Curcuma longa) on selected bacteria were evaluated. Different concentrations of turmeric extract (100, 50, 25, and 12.5 mg/mL) were prepared using 2 solvents namely water and ethanol. The antibacterial activity was tested against Bacillus species, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa at different concentration of the extract using disc diffusion method and ciprofloxacin was the control. The zones of inhibition exhibited by ethanol and aqueous extracts against test organisms ranged from 1 to 10 mm. the ethanolic extracts were more effective than the aqueous extracts exhibiting zones of inhibition ranging from 3 to 10 mm against Bacillus species, 4 to 9 mm against S aureus, and 1 to 7 mm against E coli. There was no inhibitory effect against P aeruginosa. There was significant difference between the ethanol and aqueous extracts (P < .05). This study reveal that Turmeric plant has antibacterial potential against selected organisms and may be of great use of pharmaceutical industries for the development of medicine to cure ailments and control abnormal serum lipid profile.

Recent advances in delivering free or nanoencapsulated Curcuma by-products as antimicrobial food additives

Food commodities are often contaminated by microbial pathogens in transit or during storage. Hence, mitigation of these pathogens is necessary to ensure the safety of food commodities. Globally, researchers used botanicals as natural additives to preserve food commodities from bio-deterioration, and advances were made to meet users' acceptance in this domain, as synthetic preservatives are associated with harmful effects to both consumers and environments. Over the last century, the genus Curcuma has been used in traditional medicine, and its crude and nanoencapsulated essential oils (EOs) and curcuminoids were used to combat harmful pathogens that deteriorate stored foods. Today, more research is needed for solving the problem of pathogen resistance in food commodities and to meet consumer demands. Therefore, Curcuma-based botanicals may provide a source of natural preservatives for food commodities that satisfy the needs both of the food industry and the consumers. Hence, this article discusses the antimicrobial and antioxidant properties of EOs and curcuminoids derived from the genus Curcuma. Further, the action modes of Curcuma-based botanicals are explained, and the latest advances in nanoencapsulation of these compounds in food systems are discussed alongside knowledge gaps and safety assessment where the focus of future research should be placed.

Preparation and Primary Bioactivity Evaluation of Novel Water-Soluble Curcumin-Loaded Polymeric Micelles Fabricated with Chitooligosaccharides and Pluronic F-68

Curcumin (CU) is a bioactive compound extracted from turmeric and has various advantages. However, the benefit of CU is limited by its low water solubility (11 ng/mL). This research aimed to fabricate a water-soluble CU nano-formulation with chitooligosaccharides (COS) and pluronic F-68 (PF) utilizing the polymeric micelle method. The optimized curcumin-loaded chitooligosaccharides/pluronic F-68 micelles (COSPFCU) exhibited high encapsulation efficiency and loading capacity (75.57 ± 2.35% and 10.32 ± 0.59%, respectively). The hydrodynamic diameter of lyophilized COSPFCU was 73.89 ± 11.69 nm with a polydispersity index below 0.3. The COSPFCU could be completely redispersed in water and showed high DPPH scavenging ability. Meanwhile, COSPFCU could significantly reduce the cytotoxicity of the RAW 264.7 cells compared to native CU. Furthermore, COSPFCU improved the inhibition of NO release activity at 72.83 ± 2.37% but 33.20 ± 3.41% for the CU, with a low cytotoxicity concentration in the RAW 264.7 cells.

Synergy of Plant Essential Oils in Antibiotic Therapy to Combat Klebsiella pneumoniae Infections

Increased antibiotic resistance presents a health problem worldwide. The World Health Organization published a list of pathogens considered a priority for designing new treatments. Klebsiella pneumoniae (Kp) is a top-priority microorganism, highlighting the strains that produce carbapenemases. Developing new efficient therapies or complementing existing treatments is a priority, and essential oils (EOs) provide an alternative. EOs could act as antibiotic adjuvants and enhance antibiotic activity. Employing standard methodologies, the antibacterial activity of the EOs and their synergic effect with antibiotics were detected. A string test was used to identify the impact of the EOs over the hypermucoviscosity phenotype presented by Kp strains, and Gas Chromatography-Mass Spectrometry analysis identified EOs and the composition of EOs. The potential of EOs for designing synergistic therapies with antibiotics to combat the infection of KPC diseases was demonstrated. In addition, the alteration of the hypermucoviscosity phenotype was shown as the principal mechanism of a synergic action between EOs and antibiotics. The differential composition of the EOs lets us identify some molecules that will be analyzed. Synergic activity of EOs and antibiotics can provide a solid platform for combating multiresistant pathogens that represent a severe health sector problem, such as Kp infections.

Preparation and characterization of ultrasound-assisted essential oil-loaded nanoemulsions stimulated pullulan-based bioactive film for strawberry fruit preservation

Ultrasound is a high-energy approach that can help with homogenization and dispersion in cavitation. In this study, nanoemulsions of curcumin and orange essential oil were prepared with ultrasound treatment at different times. The ultrasound-treated nanoemulsions for 10 min exhibited the smallest droplet size, the best storage, and higher thermal stability. The pullulan-based film with ultrasound-assisted nanoemulsions exhibited improved water vapor permeability and moisture content and the highest tensile strength and elongation at break. The structural analysis showed that ultrasonic treatment enhanced the H-bond, resulting in a more orderly molecular arrangement and intermolecular compatibility. Furthermore, the bioactive film had the maximum oil retention time. It possessed excellent bacteriostatic properties against Escherichia coli and Staphylococcus aureus due to the smallest oil droplets and uniform distribution in the film matrix. Besides, the weight loss and deterioration of the strawberry fruit were effectively reduced, thus prolonging the shelf life.

A comparative study of effects of curcumin and its nanoparticles on the growth, immunity and heat stress resistance of Nile tilapia (Oreochromis niloticus)

This study evaluated the effects of dietary supplementation with free- or nano-curcumin on the growth performance, immune status and heat stress resistance of Nile tilapia (Oreochromis niloticus). Seven isonitrogenous (28% protein) and isocaloric (445 kcal/100 g DM) diets were prepared. Six diets were supplemented with three levels of nano-curcumin (50 (CN50), 100 (CN100), 200 (CN200) mg kg-1 diet) or free-curcumin (50 (C50), 100 (C100), 200 (C200) mg kg-1 diet), and the control diet was left without an additive (CON). Fish (13.54 ± 0.32 g) (mean ± SD) fed the experimental diets for 65 days. Following the feeding trial, the fish were exposed to the acute heat stress by gradually raising the water temperature from 25 to 40 °C within 3 h. The fish were then exposed to 40 °C for 4 h. Results revealed the superiority of nano-curcumin over its free-form in enhancing the growth performance, with the highest results obtained at CN100, followed by CN200. Only heat stress, not the experimental diets, increased the platelets, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), leukocytes and neutrophils count, while lymphocytes decreased. The CN50 and CN100 groups showed lower activity of liver enzymes (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)) than the other treatments, while C200 gave the highest activity of these enzymes. The highest immunoglobulin (IgM) levels were detected in CN100, CN200, C100 and C200, followed by CN50. The C200 group showed higher levels of complement 3 and complement 4 (C3 and C4, respectively) than the other treatments. The C50 and CON groups gave the lowest values of IgM, C3 and C4. Cortisol levels were significantly lower in the CN50 and CN100 groups compared to the other groups. After the heat stress, ALT, AST, IgM, C3, C4, cortisol and glucose increased. Thus, nano-curcumin is more effective than its free-form in enhancing the resistance to heat stress, inducing innate immunity, lowering the stress indicators and promoting growth performance of Nile tilapia with the best concentration at 100 mg kg-1 diet.

Fabrication of Sustained Release Curcumin-Loaded Solid Lipid Nanoparticles (Cur-SLNs) as a Potential Drug Delivery System for the Treatment of Lung Cancer: Optimization of Formulation and In Vitro Biological Evaluation

The goal of current research was to develop a new form of effective drug, curcumin-loaded solid lipid nanoparticles (Cur-SLNs) and test its efficacy in the treatment of lung cancer. Different batches of SLNs were prepared by the emulsification-ultrasonication method. For the optimization of formulation, each batch was evaluated for particle size, polydispersity index (PI), zeta potential (ZP), entrapment efficiency (EE) and drug loading (DL). The formulation components and process parameters largely affected the quality of SLNs. The SLNs obtained with particle size, 114.9 ± 1.36 nm; PI, 0.112 ± 0.005; ZP, -32.3 ± 0.30 mV; EE, 69.74 ± 2.03%, and DL, 0.81 ± 0.04% was designated as an optimized formulation. The formulation was freeze-dried to remove excess water to improve the physical stability. Freeze-dried Cur-SLNs showed 99.32% of drug release and demonstrated a burst effect trailed by sustained release up to 120 h periods. The erythrocyte toxicity study of Cur-SLNs and its components demonstrated moderate hemolytic potential towards red blood cells (RBCs). The cytotoxic potential of the formulation and plain curcumin was estimated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against A549 cell line. After 48 h of incubation, Cur-SLNs demonstrated more cytotoxicity (IC₅₀ = 26.12 ± 1.24 µM) than plain curcumin (IC₅₀ = 35.12 ± 2.33 µM). Moreover, the cellular uptake of curcumin was found to be significantly higher from Cur-SLNs (682.08 ± 6.33 ng/µg) compared to plain curcumin (162.4 ± 4.2 ng/µg). Additionally, the optimized formulation was found to be stable over the period of 90 days of storage. Hence, curcumin-loaded SLNs can be prepared using the proposed cost effective method, and can be utilized as an effective drug delivery system for the treatment of lung cancer, provided in vivo studies warrant a similar outcome.

Methods to Improve the Solubility of Curcumin from Turmeric

Turmeric is a strong-taste component of spices characteristic of Indian cuisine. It is obtained from the turmeric rhizome (Curcumae longae rhizoma) and has been used for thousands of years not only for culinary purposes, but also for medicinal purposes. It contains a group of organic compounds called curcuminoids. Curcumin is the main representative of this group of compounds which is also most frequently studied. In recent years, bioactive curcuminoids (including curcumin in the first place) have become more and more popular due to a wide spectrum of their biological activity. The anticancer, antibacterial, anti-inflammatory, and antiaging effects of curcumin have been confirmed by numerous in vitro and in vivo studies, as well as in clinical trials. However, an obstacle to simple, clinical application of curcumin is its poor bioavailability (which is due to its hydrophobic nature) and its very weak water solubility. Therefore, many scientists are working on improving the solubility of curcumin in water, which is the topic of the present article. Attempts have been made to combine curcumin with nanoparticles (polysaccharide or silica). Nanosuspensions or complexes with cyclodextrins are also considered. A promising direction is the search for new polymorphic varieties as well as obtaining cocrystals with curcumin which are characterized by better water solubility.

Curcumae Rhizoma: A botanical drug against infectious diseases

Curcumae Rhizoma is the dry rhizome coming from Curcuma longa L. which grow widely in tropical south and southwest Asia. It has been used to treat conditions such as dermatoses, infections, stress, and depression. Moreover, in China, Curcumae Rhizoma and its active constituents have been made into different pharmaceutical preparations. Growing evidence suggests that these preparations can exert antioxidant, anti-inflammatory, and anti-cancer effects, which may play crucial roles in the treatment of various diseases, including cancer, infectious-, autoimmune-, neurological-, and cardiovascular diseases, as well as diabetes. The anti-infective effect of Curcumae Rhizoma has become a popular field of research around the world, including for the treatment of COVID-19, influenza virus, hepatitis B virus, human immunodeficiency virus, and human papilloma virus, among others. In this paper, the basic characteristics of Curcumae Rhizoma and its active constituents are briefly introduced, and we also give an overview on their applications and mechanisms in infectious diseases.

Essential oil composition of Curcuma species and drugs from Asia analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry

Essential oils (EOs) comprised of various bioactive compounds have been widely detected in the Curcuma species. Due to the widespread distribution and misidentification of Curcuma species and differences in processing methods, inconsistent reports on major compounds in rhizomes of the same species from different geographical regions are not uncommon. This inconsistency leads to confusion and inaccuracy in compound detection of each species and also hinders comparative study based on EO compositions. The present study aimed to characterize EO compositions of 12 Curcuma species, as well as to detect the compositional variation among different species, and between the plant specimens and their related genetically validated crude drug samples using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. The plant specimens of the same species showed similar EO patterns, regardless of introducing from different geographical sources. Based on the similarity of EO compositions, all the specimens and samples were separated into eight main groups: C. longa; C. phaeocaulis, C. aeruginosa and C. zedoaria; C. zanthorrhiza; C. aromatica and C. wenyujin; C. kwangsiensis; C. amada and C. mangga; C. petiolata; C. comosa. From EOs of all the specimens and samples, 54 major compounds were identified, and the eight groups were chemically characterized. Most of the major compounds detected in plant specimens were also observed in crude drug samples, although a few compounds converted or degraded due to processing procedures or over time. Orthogonal partial least squares-discriminant analysis allowed the marker compounds to discriminate each group or each species to be identified.

Evaluation of Antibacterial Activity of Extracts of Curcuma Longa L. Rhizome and Estimation of Curcuminoid by HPLC

Curcuma longa L. rhizome extracts have polyphenolic secondary metabolites called curcuminoid and various volatile oils. These compounds exhibit wide spectrum of antibacterial activity. Ethanol and petroleum ether C. longa rhizome extracts were studied for their antibacterial action against two bacteria, Escherichia coli and Staphylococcus aureus. This activity had evaluated by employing Agar Well Diffusion method. Curcuminoid was interpreted by pattern of High Performance Liquid Chromatography (HPLC). The ethanol extract exhibited inhibitory effects against E. coli and S. aureus at concentration 150 mg/ml with diameter of inhibition zone (23.000 ± 0.57735 and 27.000 ± 0.57735mm) respectively. On the contrary, petroleum ether extract had inhibitory effects for E. coli and S. aureus at concentration 150 mg/ml in diameter of inhibition zone (39.000 ± 0.57735 and 41.000 ± 0.57735mm) respectively. Quantitative analysis for the curcuminoid compounds from C. longa rhizome extracts revealed highest curcumin, demethoxycurcumin and bisdemethoxycurcumin (9.12, 5.93 and 23.96 µg /ml) respectively in the extract of petroleum ether. We concluded that the C. longa extracts exhibited inhibitory effects against pathological bacterial growth. The essential oils obtained by petroleum ether extract of C. longa rhizome was more influential inhibition than ethanol extract against E. coli and S. aureus.

Applications of Essential Oils and Plant Extracts in Different Industries

Essential oils (EOs) and plant extracts are sources of beneficial chemical compounds that have potential applications in medicine, food, cosmetics, and the agriculture industry. Plant medicines were the only option for preventing and treating mankind's diseases for centuries. Therefore, plant products are fundamental sources for producing natural drugs. The extraction of the EOs is the first important step in preparing these compounds. Modern extraction methods are effective in the efficient development of these compounds. Moreover, the compounds extracted from plants have natural antimicrobial activity against many spoilage and disease-causing bacteria. Also, the use of plant compounds in cosmetics and hygiene products, in addition to their high marketability, has been helpful for many beauty problems. On the other hand, the agricultural industry has recently shifted more from conventional production systems to authenticated organic production systems, as consumers prefer products without any pesticide and herbicide residues, and certified organic products command higher prices. EOs and plant extracts can be utilized as ingredients in plant antipathogens, biopesticides, and bioherbicides for the agricultural sector. Considering the need and the importance of using EOs and plant extracts in pharmaceutical and other industries, this review paper outlines the different aspects of the applications of these compounds in various sectors.

Curcuminoids, a major turmeric component, have a sleep-enhancing effect by targeting the histamine H1 receptor

Turmeric (Curcuma longa) had been considered as a universal panacea in functional foods and traditional medicines. In recent, the sedative-hypnotic effect of turmeric extract (TE) was reported. However, sleep-promoting compounds in TE have been not yet demonstrated. Curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) are the major constituents of turmeric being responsible for its various biological activities. Therefore, they can be first assumed to be sedative-hypnotic compounds of TE. In the present study, we aimed to investigate the effects and underlying mechanisms of curcuminoids and each constituent on the sleep-wake cycle of mice. Molecular docking studies, histamine H1 receptor (H1R) binding assays, and H1R knockout animal studies were used to investigate the molecular mechanisms underlying the sleep-promoting effects. Curcuminoids and their constituents reduced sleep latency and increased sleep duration in the pentobarbital-induced sleep test in mice. In addition, curcuminoids significantly increased the duration of NREMS and reduced sleep latency without altering the REMS and delta activity. Curcumin, demethoxycurcumin, and bisdemethoxycurcumin were predicted to interact with H1R in the molecular model. In the binding affinity assay, we found that curcuminoids, as well as their constituents, significantly bind to H1R with the K_i value of 1.49 μg mL^-1. Furthermore, sleep latency was reduced and NREMS frequency was increased following curcuminoid administration in wild-type mice but not in H1R knockout mice. Therefore, we conclude that curcuminoids reduce sleep latency and enhance the quantity of NREMS by acting as modulators of H1R, indicating their usefulness in treating insomnia.

Formulation, Characterization and Evaluation of Innovative O/W Emulsions Containing Curcumin Derivatives with Enhanced Antioxidant Properties

In the present study, a series of semisolid Oil in Water (O/W) emulsions containing different Curcumin (Cur) derivatives (Cur powder, Cur extract and Cur complexed with β-cyclodextrin) in varying concentrations, were prepared. Initially, Dynamic Light Scattering (DLS), microscopy, pH and viscosity measurements were performed to evaluate their stability over time. Moreover, the effect of the active cosmetic substances on the Sun Protection Factor (SPF), antimicrobial and antioxidant properties of the prepared emulsions was investigated. It was observed that emulsions containing Cur extract and Cur β-cyclodextrin complex presented great viscosity and pH stability for up to 90 days of storage contrary to the emulsions containing Cur powder which showed unstable behavior due to the formation of agglomerates. All samples presented SPF values between 2.6 and 3.2. The emulsions with Cur in all forms exhibited high antioxidant activity, whereas the emulsion containing Cur β-cyclodextrin complex presented the highest value. Despite their improved stability and antioxidant activity, the emulsions containing Cur extract and Cur-β-cyclodextrin exhibited a low percentage of antimicrobial activity against E. coli and Staphylococcus bacteria. Instead, the emulsions containing Cur powder presented a reduction rate over 90 % against E. coli and Staphylococcus colonies.

Nutraceutical Preventative and Therapeutic Potential in Neuroblastoma: From Pregnancy to Early Childhood

Neuroblastoma (NB) is a highly malignant embryonic extracranial solid tumor that arises from sympathoadrenal neuroblasts of neural crest origin. In addition to genetic factors, NB has been linked to maternal exposure to a variety of substances during pregnancy. Recent interest in the potential of nutrients to prevent cancer and reduce malignancy has resulted in the identification of several nutraceuticals including resveratrol, curcumin, and molecular components of garlic, which together with certain vitamins may help to prevent NB development. As NBs arise during fetal development and progress during early childhood, specific NB inhibiting nutraceuticals and vitamins could enhance the preventative influence of maternal nutrition and breast feeding on the development and early progression of NB. In this article, we review NB inhibitory nutraceuticals and vitamins, their mechanisms of action and expound their potential as maternal nutritional supplements to reduce NB development and progression during fetal growth and early childhood, whilst at the same time enhancing maternal, fetal, and infant health.

Molecular insights and therapeutic implications of nanoengineered dietary polyphenols for targeting lung carcinoma: part I

Lung cancer is the second leading cause of cancer-related mortality globally, and non-small-cell lung cancer accounts for most lung cancer cases. Nanotechnology-based drug-delivery systems have exhibited immense potential in lung cancer therapy due to their fascinating physicochemical characteristics, in vivo stability, bioavailability, prolonged and targeted delivery, gastrointestinal absorption and therapeutic efficiency of their numerous chemotherapeutic agents. However, traditional chemotherapeutics have systemic toxicity issues; therefore, dietary polyphenols might potentially replace them in lung cancer treatment. Polyphenol-based targeted nanotherapeutics have demonstrated interaction with a multitude of protein targets and cellular signaling pathways that affect major cellular processes. This review summarizes the various molecular mechanisms and targeted therapeutic potentials of nanoengineered dietary polyphenols in the effective management of lung cancer.

In Silico Analysis and Comparative Molecular Docking Study of FDA Approved Drugs with Transforming Growth Factor Beta Receptors in Oral Submucous Fibrosis

Abstract

Oral sub-mucous fibrosis (OSMF) is a severe crippling malignant disorder which affects the oral mucosa. The transforming growth factor beta (TGF-β) is one of the cytokines involved with the cell proliferation, cell growth and apoptosis. Several traditional and synthetic medications have been tried in OSMF. This study attempts to identify the FDA approved drugs (including both synthetic and herbal medications) with least side effects, highest efficacy and robust dynamic mechanism for the treatment of OSMF. A ligand library comprising of FDA approved drug compounds was prepared using ChEMBL database. Molecular docking was carried out using GOLD suite 5.2.2. The docked complexes which had the highest binding affinities and lowest energy were deployed to a molecular dynamic simulation using MDweb server. Further, SwissADME  was used to study ADME, physicochemistry, drug-likeness, pharmacokinetics and medicinal chemistry friendliness properties. Our docking results suggest that ligands-Curcumin, Curcumin Pyrazole and Demethoxycurcumin, which are all herbal in nature, have a better binding affinity and the best docking scores for both TGF-β type I and TGF-β type II receptors. The molecular dynamics study discerns that the structures have become more stable with less energy. The pharmacokinetics and pharmacodynamics analysis, physicochemical properties and toxicity prediction suggest that Curcumin is the optimal lead compound and holds the potential to be used as an effective drug for the treatment of OSMF. Curcumin, a FDA approved herbal compound, can be used as an effective drug for the treatment of OSMF.

Graphic Abstract

Supercritical Fluid Extraction with CO2 of Curcuma longa L. in Comparison to Conventional Solvent Extraction

Curcuma longa L. is a traditional medicinal and spice plant containing a variety of lipophilic active substances with promising therapeutic properties. In this work, the solvent properties of supercritical carbon dioxide in a pressure and temperature range of 75–425 bar and 35–75 °C were investigated when Curcuma longa rhizomes were extracted. The three main curcuminoids, namely curcumin, demethoxycurcumin, and bisdemethoxycurcumin, together with the three main constituents of the essential oil, i.e., ar-turmerone, α-turmerone, and β-turmerone, were analyzed in the resulting extracts. For statistical evaluation, experiments were performed employing a full factorial design, in which flow rate, extraction time, and drug load were kept constant. Within the given conditions, the experimental design revealed an optimum yield of all aforementioned substances, when supercritical carbon dioxide extraction was performed at 425 bar and 75 °C. For comparison, solvent extracts using methanol and n-hexane were prepared and their main components were characterized using LC-MS. The stability of the extracts was monitored upon storage for 6 months at 22 and 40 °C under protection from light. The decomposition of individual compounds was mainly observed in the presence of residual water in the extracts.

Pharmacological Profile, Bioactivities, and Safety of Turmeric Oil

The pharmacological attributes of turmeric have been extensively described and frequently related to the action of curcuminoids. However, there is also scientific evidence of the contribution of turmeric oil. Since the oil does not contain curcuminoids in its composition, it is crucial to better understand the therapeutic role of other constituents in turmeric. The present review discusses the pharmacokinetics of turmeric oil, pointing to the potential application of its active molecules as therapeutic compounds. In addition, the bioactivities of turmeric oil and its safety in preclinical and clinical studies were revised. This literature-based research intends to provide an updated overview to promote further research on turmeric oil and its constituents.

Comparative Insights into the Antimicrobial, Antioxidant, and Nutritional Potential of the Solanum nigrum Complex

Solanum nigrum is a traditional medicinal plant renowned as a cure for many diseases due to the presence of bioactive compounds. The Solanum nigrum complex refers to a group of more than 30 closely related but morphologically distinct taxa. Five indigenous taxa of this complex were investigated for their medicinal potential by using methanolic extracts. The efficacy of each plant was different for each of the seven bacteria studied. On comparing the MIC values, S. americanum was found to be most potent against Bacillus licheniformis (34 µg/mL), S. chenopodioides against Escherichia coli (78 µg/mL), S. nigrum against Bacillus licheniformis (49 µg/mL) and Escherichia coli (49 µg/mL), S. retroflexum against Escherichia coli (30 µg/mL), and S. villosum against Proteus mirabilis (45 µg/mL). The extracts were also subjected to six antioxidant assays. Moderate scavenging activity was observed by all plants in the DPPH free radical assay, but S. chenopodioides was the most effective. The total phenolic contents of the five plants were comparable, but the gallic acid equivalents of S. americanum and S. nigrum were the highest (26.58 mg/100 g GAE). The highest Trolox equivalent antioxidant capacity was observed for S. retroflexum, with the ABTS assay giving a TEAC value of 33.88 mM/100 g of dry weight. Metal-chelating activity against Fe2+ was observed to be highest for S. chenopodioides (70.37%). The FRAP value of S. nigrum was the highest (8.5 mM FeSO4·7H2O) among all taxa. The lipid peroxidation trend was very similar for all five samples. The results suggest the specified medicinal use of different members of the Solanum nigrum complex, which will also have significant nutritional value.

Reconnoitering the Therapeutic Role of Curcumin in Disease Prevention and Treatment: Lessons Learnt and Future Directions

Turmeric is a plant with a very long history of medicinal use across different cultures. Curcumin is the active part of turmeric, which has exhibited various beneficial physiological and pharmacological effects. This review aims to critically appraise the corpus of literature associated with the above pharmacological properties of curcumin, with a specific focus on antioxidant, anti-inflammatory, anticancer and antimicrobial properties. We have also reviewed the different extraction strategies currently in practice, highlighting the strengths and drawbacks of each technique. Further, our review also summarizes the clinical trials that have been conducted with curcumin, which will allow the reader to get a quick insight into the disease/patient population of interest with the outcome that was investigated. Lastly, we have also highlighted the research areas that need to be further scrutinized to better grasp curcumin’s beneficial physiological and medicinal properties, which can then be translated to facilitate the design of better bioactive therapeutic leads.

Efficacy and safety of adjuvant curcumin therapy in ulcerative colitis: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Curcumin, an active polyphenol extracted from Traditional Chinese medicine Curcuma longa (turmeric), has shown many health-related benefits and pharmacological effects. Adjuvant curcumin therapy for ulcerative colitis has become increasingly popular, but its efficacy and safety of which is still controversial. The purpose of this study is to evaluate the efficacy and safety of adjuvant curcumin therapy in ulcerative colitis.

MATERIALS AND METHODS

The Medline, EMBASE, the Cochrane Library, CNKI, VIP, WanFang, and SinoMed databases were searched from inception to June 2021, to identify all randomized controlled clinical trials with adjuvant curcumin therapy in ulcerative colitis. The primary outcomes were clinical and endoscopic remission, and subgroup analyses were also performed.

RESULTS

Six randomized trials with a total of 385 participants were included in this study. Qualified trials recommended that adjuvant curcumin therapy for ulcerative colitis was effective in inducing clinical remission (RR = 2.10, 95% CI 1.13 to 3.89), but not in clinical improvement (RR = 1.62, 95% CI 1.00 to 2.61), endoscopic remission (RR = 4.17, 95% CI 0.63 to 27.71) or endoscopic improvement (RR = 4.13, 95% CI 0.20 to 87.07). Included studies showed that appropriate dosage, formation, longer duration, and topical medication may have a greater potential advantage. No severe adverse effects had been reported.

CONCLUSIONS

Available evidence suggested that adjuvant curcumin therapy may be effective for clinical remission in ulcerative colitis patients without causing severe adverse effects. The appropriate methods of administration can achieve better curative effect, which requires further study to verify.

Gallium-Curcumin Nanoparticle Conjugates as an Antibacterial Agent against Pseudomonas aeruginosa: Synthesis and Characterization

Combating antibiotic resistance has found great interest in the current clinical scenario. Pseudomonas aeruginosa, an opportunistic multidrug-resistant pathogen, is well known for its deadly role in hospital-acquired infections. Infections by P. aeruginosa are among the toughest to treat because of its intrinsic and acquired resistance to antibiotics. In this study, we project gallium-curcumin nanoparticle (GaCurNP) conjugates as a prospective candidate to fight against P. aeruginosa. The synthesized GaCurNPs were spherical with an average size ranging from 25-35 nm. Analysis by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy deduced the nature of interaction between gallium and curcumin. Conjugate formation with gallium was found to improve the stability of curcumin at the physiological pH. When tested after 24 h of contact, at the physiological pH and 37 °C, the degradation of curcumin bound in the GaCurNPs was 26%, while that of native curcumin was 95%. The minimum inhibitory concentration (MIC) of GaCurNPs was found to be 82.75 μg/mL for P. aeruginosa (ATCC 27853). GaCurNPs also showed excellent biofilm inhibition at 4MIC concentration. Raman spectroscopic analysis showed that GaCurNPs are capable of disrupting the cells of P. aeruginosa within 3 h of contact. Live/dead imaging also confirmed the compromised membrane integrity in cells treated with GaCurNPs. Scanning electron microscopy analysis showed membrane lysis and cell structure damage. The AlamarBlue assay showed that when L929 cell lines were treated with GaCurNPs with concentrations as high as 350 μg/mL, the cell viability elicited by the nanoparticles was 70.89%, indicating its noncytotoxic nature. In short, GaCurNPs appear to be a promising antibacterial agent capable of fighting a clinically significant pathogen, P. aeruginosa.

Antimicrobial Potential of Curcumin: Therapeutic Potential and Challenges to Clinical Applications

Curcumin is a bioactive compound that is extracted from Curcuma longa and that is known for its antimicrobial properties. Curcuminoids are the main constituents of curcumin that exhibit antioxidant properties. It has a broad spectrum of antibacterial actions against a wide range of bacteria, even those resistant to antibiotics. Curcumin has been shown to be effective against the microorganisms that are responsible for surgical infections and implant-related bone infections, primarily Staphylococcus aureus and Escherichia coli. The efficacy of curcumin against Helicobacter pylori and Mycobacterium tuberculosis, alone or in combination with other classic antibiotics, is one of its most promising antibacterial effects. Curcumin is known to have antifungal action against numerous fungi that are responsible for a variety of infections, including dermatophytosis. Candidemia and candidiasis caused by Candida species have also been reported to be treated using curcumin. Life-threatening diseases and infections caused by viruses can be counteracted by curcumin, recognizing its antiviral potential. In combination therapy with other phytochemicals, curcumin shows synergistic effects, and this approach appears to be suitable for the eradication of antibiotic-resistant microbes and promising for achieving co-loaded antimicrobial pro-regenerative coatings for orthopedic implant biomaterials. Poor water solubility, low bioavailability, and rapid degradation are the main disadvantages of curcumin. The use of nanotechnologies for the delivery of curcumin could increase the prospects for its clinical application, mainly in orthopedics and other surgical scenarios. Curcumin-loaded nanoparticles revealed antimicrobial properties against S. aureus in periprosthetic joint infections.

Exploitation of the Antibacterial Properties of Photoactivated Curcumin as ‘Green’ Tool for Food Preservation

In the search for non-chemical and green methods to counteract the bacterial contamination of foods, the use of natural substances with antimicrobial properties and light irradiation at proper light waves has been extensively investigated. In particular, the combination of both techniques, called photodynamic inactivation (PDI), is based on the fact that some natural substances act as photosensitizers, i.e., produce bioactive effects under irradiation. Notably, curcumin is a potent natural antibacterial and effective photosensitizer that is able to induce photodynamic activation in the visible light range (specifically for blue light). Some practical applications have been investigated with particular reference to food preservation from bacterial contaminants.

Honey-based trap for Pseudomonas: a sustainable prototype for water disinfection

This paper introduces a novel prototype for the removal of Pseudomonas from water samples. Bacterial cells have the tendency to get attracted towards specific chemicals (chemotaxis); a 'honey-based trap' (henceforth, addressed as 'honey-trap') strip was conceptualized by integrating a combination of serine, pseudomonas-specific chemoattractant and honey to attract and inhibit the bacteria in situ. Honey, a natural antimicrobial agent, has garnered the attention as an effective inhibitor for Pseudomonal biofilms and wound infections. Dipping serine side of the strip attracted bacteria towards honey-trap, whereby the porous nature of the strip facilitated the 'trapping' and subsequent diffusion of the bacterial cells towards honey-adsorbed end of the strip. This 'honey-trap' reportedly leads to the targeted elimination of Pseudomonas, hence facilitating its removal. The percentage efficacy of this 'honey-trap' device is 96% with a log reduction equivalent to 1.6 within a time frame of 2 h. Pseudomonas aeruginosa, although, not a natural contaminant of potable water, enters circulation due to improperly maintained plumbing fixtures and storage facilities. Honey-trap strip is an easy to use, biodegradable and cost-effective sustainable solution, and thus a scaled-up version of this device may enable substantial improvement in quality of potable water. Schematics showing the preparation and working of the Pseudomonas Honey-trap. Serine as an attractant and honey as an inhibitor was absorbed on filter strips (HT) for use. The strip was dipped in culture from serine end. After different time period of incubation, difference in bacterial load was confirmed by measuring the electrical conductivity and OD600nm of the culture. Additionally, inhibitory effect of HS was confirmed by placing the strip incubated with culture on agar plates and differences in bacterial lawn were monitored. Removal of bacterial cells from the suspension was also confirmed using absorption spectroscopy.

Development and Evaluation of Tannic Acid-Coated Nanosuspension for Enhancing Oral Bioavailability of Curcumin

Curcumin (CUR) has been used in the treatment of various diseases such as cough, fever, skin disease, and infection because of various biological benefits such as anti-inflammatory, antiviral, antibacterial, and antitumor activity. However, CUR is a BCS class 4 group and has a limitation of low bioavailability due to low solubility and permeability. Therefore, the purpose of this study is to prepare a nanosuspension (NSP) loaded with CUR (CUR-NSP) using a statistical design approach to improve the oral bioavailability of CUR, and then to develop CUR-NSP coated with tannic acid to increase the mucoadhesion in the GI tract. Firstly, the optimized CUR-NSP, composed of sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone/vinyl acetate (PVP/VA), was modified with tannic acid (TA). The particle size and polydispersity index of the formulation measured by laser scattering analyzer were 127.7 ± 1.3 nm and 0.227 ± 0.010, respectively. In addition, the precipitation in distilled water (DW) was 1.52 ± 0.58%. Using a differential scanning calorimeter and X-ray diffraction analysis, the stable amorphous form of CUR was confirmed in the formulation, and it was confirmed that CUR-NSP formulation was coated with TA through a Fourier transform-infrared spectroscopy. In the mucoadhesion assay using the turbidity, it was confirmed that TA-CUR-NSP had higher affinity for mucus than CUR-NSP under all pH conditions. This means that the absorption of CUR can be improved by increasing the retention time in the GI tract of the formulation. In addition, the drug release profile showed more than 80% release, and in the cellular uptake study, the absorption of the formulation (TA-CUR-NSP) containing TA acting as an inhibitor of P-gp was increased by 1.6-fold. In the evaluation of antioxidant activity, the SOD activity of TA-CUR-NSP was remarkably high due to TA, which improves cellular uptake and has antioxidant activity. In the pharmacokinetic evaluation, the maximum drug plasma concentration of the TA-coated NSP formulation was 7.2-fold higher than that of the pure drug. In all experiments, it was confirmed that the TA-CUR-NSP is a promising approach to overcome the low oral bioavailability of CUR.

Curcumin reduced fat accumulation in Caenorhabditis elegans

Curcumin, the primary bioactive substance in turmeric, is known to be associated with weight loss. In this study, we employed Caenorhabditis elegans, a well-established in vivo nematode model to explore the role of curcumin in regulating lipid metabolism. C. elegans administrated with curcumin (10, 25 and 50 μM) exhibited significantly reduced fat accumulation, along with smaller body size (width) when compared to the control, without significantly affecting the feeding behavior. Locomotive activity (average moving speed) was significantly increased by curcumin treatment, suggesting a potential increase in energy expenditure. The reduced fat accumulation by curcumin was dependent on lipogenesis-associated genes, sbp-1 (encodes the homolog of sterol response element binding proteins) and fat-6 (encodes a homolog of stearoyl-CoA desaturase), as curcumin significantly down-regulated the expression levels of these two genes and its fat reduction effect was nulled by the mutation of sbp-1 and fat-6. Additionally, the increased locomotive activity by curcumin was dependent on sbp-1. Current results suggest that curcumin decreases fat accumulation by inhibiting sbp-1/fat-6-mediated signaling in Caenorhabditis elegans.

Antimetastatic Effects of Curcumin in Oral and Gastrointestinal Cancers

Gastrointestinal (GI) cancers are known as frequently occurred solid malignant tumors that can cause the high rate mortality in the world. Metastasis is a significant destructive feature of tumoral cells, which directly correlates with decreased prognosis and survival. Curcumin, which is found in turmeric, has been identified as a potent therapeutic natural bioactive compound (Curcuma longa). It has been traditionally applied for centuries to treat different diseases, and it has shown efficacy for its anticancer properties. Numerous studies have revealed that curcumin inhibits migration and metastasis of GI cancer cells by modulating various genes and proteins, i.e., growth factors, inflammatory cytokines and their receptors, different types of enzymes, caspases, cell adhesion molecules, and cell cycle proteins. Herein, we summarized the antimetastatic effects of curcumin in GI cancers, including pancreatic cancer, gastric cancer, colorectal cancer, oral cancer, and esophageal cancer.

Dietary Curcumin Improves Energy Metabolism, Brain Monoamines, Carcass Traits, Muscle Oxidative Stability and Fatty Acid Profile in Heat-Stressed Broiler Chickens

The aim of the present study was to elucidate the impacts of dietary curcumin supplementation on energy metabolism, brain monoamines and muscle oxidative stability in heat-stressed broilers. In total, 120 day-old chicks were allocated into three equal groups of four replicates. The first group (T₁) was maintained on a thermoneutral condition, while the second group (T₂) was subjected to 8 h of thermal stress (34 °C), and both groups fed the basal diet with no supplement. The third group (T₃) was exposed to the same thermal stress conditions and fed the basal diet supplemented with curcumin (100 mg kg^-1 diet). The dietary curcumin supplementation significantly increased the breast yield (p = 0.004), but reduced the percentage of abdominal fat (p = 0.017) compared with the T₂ group. The addition of curcumin to broiler diets significantly improved the levels of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) in breast and thigh muscles compared with the T₂ group (p < 0.05). The curcumin-supplemented group showed significantly lower levels of malondialdehyde in the breast and thigh muscles than that of the T₂ group (p = 0.001 and 0.015, respectively). The dietary curcumin supplementation significantly improved the levels of ATP and CoQ10 in liver tissues (p = 0.012 and 0.001, respectively) and brain serotonin (p = 0.006) as compared to the T2 group. Meanwhile, the heat-stressed group showed significantly higher levels of ADP and Na,K-ATPase in the liver tissues than that of the other experimental groups (p = 0.011 and 0.027, respectively). It could be concluded that dietary curcumin supplementation may improve carcass yield, energy biomarkers, brain serotonin and muscle oxidative stability of heat-stressed broiler chickens.

Antibacterial and Anti-Inflammatory Potential of Polyherbal Formulation Used in Chronic Wound Healing

Objective

Polyherbal formulations Jathyadi Thailam and Jatyadi Ghritam (JT) are used in Indian traditional medicine for diabetic chronic wounds, fistula, fissure, eczema, and burn management. We aimed to investigate the antibacterial and anti-inflammatory properties of crude hexane and ethanol extracts of JT formulations.

Methods

Antibacterial activity of JT extracts was tested to estimate minimum inhibitory concentrations (MICs) against nine reference bacterial strains, including one methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant (MDR) Pseudomonas aeruginosa, and clinical strains of methicillin-susceptible S.aureus (MSSA), all involved in diabetic foot infection. The anti-inflammatory activity of plant extracts was evaluated in LPS-treated macrophage cells by measuring the mRNA levels and secretion of inflammatory mediators.

Results

The antibacterial activity of JT extracts was higher against Gram (+) bacteria, with the MICs varying from 1.95 to 62.5 mg/mL. Gram (−) bacteria were only susceptible to ethanol extracts of JT. Plant extracts were found to be the most active against the reference and clinical strains of MSSA, MRSA, and biofilm-forming S. epidermidis. JT extracts efficiently inhibited in a dose-dependent manner the mRNA expression and protein secretion of proinflammatory cytokines IL-6 and IL-1β, and chemokines MCP-1 and CXCL10 in LPS-challenged macrophages.

Conclusion

In the present study, we have shown that extracts of JT formulations possess potent antibacterial and anti-inflammatory properties that could be involved in chronic wound healing activity and has the potential to be used as external add-on therapy in the management of multidrug-resistant bacterial infections at the wound.

Efficacy of curcumin for wound repair in diabetic rats/mice: a systematic review and meta-analysis of preclinical studies

BACKGROUND

Curcumin possesses multiple bioactivities that have beneficial effects on diabetic foot ulcers. Herein, we aimed to conduct a systematic preclinical review of 9 studies including a total of 262 animals, to assess the possible mechanisms of curcumin for wound healing in diabetic animals.

METHODS

Five databases were searched from inception to May 12, 2020; Rev-Man 5.3 software was applied for data analyses. Cochrane Collaboration's tool 10-item checklist was used to evaluate the methodological quality, and data revealed scores of risk of bias ranging from 2 to 5.

RESULTS

Meta-analysis indicated that curcumin had significant effects on wound healing rate and blood vessel density when compared with control (P < 0.05). The wound regeneration properties of curcumin for diabetic wounds are thought to mainly work through the possible mechanisms of antioxidation, enhanced cell proliferation, increased collagen formation, and angiogenesis. However, the anti-inflammatory effect on wounds in diabetic animals remains controversial.

CONCLUSIONS

The findings indicate that more randomized controlled trials should be pursued to obtain more reliable results regarding inflammatory response. Overall, curcumin might be a probable candidate for diabetic foot ulcers and may contribute to future clinical trials.

Dietary turmeric (Curcuma longa L.) supplementation improves growth performance, short-chain fatty acid production, and modulates bacterial composition of weaned piglets

In livestock nutrition, natural feed additives are gaining increased attention as alternatives to antibiotic growth promoters to improve animal performance. This study investigated the effects of dietary turmeric supplementation on the growth performance and gut health of weaned piglets. A total of 48 weaned piglets (Duroc × [Landrace × Yorkshire]) were used in a 6-week feeding trial. All piglets were allotted to two dietary treatments: corn-soybean meal basal diet without turmeric (control) and with 1% weight per weight (w/w) turmeric powder (turmeric). The results showed that dietary inclusion of turmeric with the basal diet improved final body weight and total average daily gain (p < 0.05). The concentrations of short-chain fatty acids in the fecal samples, including acetic, butyric, and propionic acids, were higher in the turmeric group (p < 0.05). The villus height-to-crypt depth ratio was higher in the ileum of turmeric-fed piglets (p = 0.04). The 16S rRNA gene sequencing of fecal microbiota indicated that, at the phylum level, Firmicutes and Bacteroidetes were the most predominant taxa in all fecal samples. Bacteroidetes were significantly decreased in the turmeric group compared to the control group (p = 0.021). At the genus level, turmeric showed a decreased abundance of Prevotella (p = 0.021) and an increasing trend of Lactobacillus (p = 0.083). Among the total detected species, nine bacterial species showed significant differences between the two groups. The results of this study indicated that turmeric altered the gut microbiota and short-chain fatty acid production. This suggests that turmeric could be used as a potential alternative growth promoter for piglets.

Experimental and clinical reports on anti-inflammatory, antioxidant, and immunomodulatory effects of Curcuma longa and curcumin, an updated and comprehensive review

Curcuma longa (C. longa) or turmeric is a plant with a long history of use in traditional medicine, especially for treating inflammatory conditions C. longa and its main constituent, curcumin (CUR), showed various pharmacological effects such as antioxidant and anti-microbial properties. The updated knowledge of anti-inflammatory, antioxidant, and immunomodulatory effects of C. longa and CUR is provided in this review article. Pharmacological effects of C. longa, and CUR, including anti-inflammatory, antioxidant, and immunomodulatory properties, were searched using various databases and appropriate keywords until September 2020. Various studies showed anti-inflammatory effects of C. longa and CUR, including decreased white blood cell, neutrophil, and eosinophil numbers, and its protective effects on serum levels of inflammatory mediators such as phospholipase A2 and total protein in different inflammatory disorders. The antioxidant effects of C. longa and CUR were also reported in several studies. The plant extracts and CUR decreased malondialdehyde and nitric oxide levels but increased thiol, superoxide dismutase, and catalase levels in oxidative stress conditions. Treatment with C. longa and CUR also improved immunoglobulin E (Ig)E, pro-inflammatory cytokine interleukin 4 (IL)-4, transforming growth factor-beta, IL-17, interferon-gamma levels, and type 1/type 2 helper cells (Th1)/(Th2) ratio in conditions with disturbance in the immune system. Therefore C. longa and CUR showed anti-inflammatory, antioxidant, and immunomodulatory effects, indicating a potential therapeutic effect of the plant and its constituent, CUR, for treating of inflammatory, oxidative, and immune dysregulation disorders.

Direct interactions between cationic liposomes and bacterial cells ameliorate the systemic treatment of invasive multidrug-resistant Staphylococcus aureus infections

Invasive infections caused by antibiotic-resistant Staphylococcus aureus have posed a great threat to human health. To tackle this problem, a cationic liposomal Curcumin (C-LS/Cur) was developed and its effect against antibiotic-resistant S. aureus was investigated in this study. As expected, C-LS/Cur exhibited greater bactericidal capacity compared with its counterparts, probably because the negatively charged S. aureus favors electrostatic interactions rather than intercalation with cationic liposomal vesicles at the beginning of endocytic process, thereby effectively delivering Cur to its targets. We confirmed this hypothesis by monitoring zeta potential variation, collecting visual evidences through CLSM, FCM and TEM, and determining binding kinetics by BLI. Moreover, an excellent therapeutic efficacy of C-LS/Cur against invasive murine infection was also observed, which was due to the enhanced accumulation and retention in the targets. Therefore, cationic liposomes have great potential for the clinical application in the treatment of invasive antibiotic-resistant S. aureus infections.

Free radical scavenging capacity, antibacterial activity and essential oil composition of turmeric (Curcuma domestica) varieties grown in Ethiopia

Turmeric is a known spice indispensable for food preparation and is reported to possess different chemical properties and biological activities. The objective of this study was to determine the effects of variety and type of extracts on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) reducing capacity, antibacterial activity, and chemical composition of essential oil from turmeric varieties cultivated in Ethiopia. The results from the statistical analysis revealed that the highest total curcuminoids content (6.81% m/m), essential oil (6.37% v/m), methanol extract (13.42% v/m) were obtained from Dame variety. On the other hand, the lowest curcuminoids (5.12% m/m), methanol extract (10.58% v/m) and essential oil (3.92% v/m) contents were obtained from HT3/2002 variety. Dame variety also had the highest total polyphenol content (97.55 mg GAE/g) and radical scavenging capacity (46.58 16 μg/mL) with the lowest IC₅₀ value (23.05 μg/mL). Among the tested microorganisms with turmeric extracts, growth inhibition was observed against S. aureus. The results also indicated that three compounds, namely α-Turmerone (32.41 and 35.16%), ar-Turmerone (25.20 and 25.47%), and Curlone (17.98 and 18.19%) dominated 75% of the essential oil component in Dame and Bonga 51/71 varieties, respectively. In summary, the results of this study revealed that extracts from Dame variety have strong biological potential with desired antioxidant and antibacterial activities.