Plant Flavonoids: Chemical Characteristics and Biological Activity

Excellent Antimicrobial, Antioxidant, and Catalytic Activities of Medicinal Plant Aqueous Leaf Extract Derived Silver Nanoparticles

Antimicrobial resistance is one of the crucial public health challenges that we need to combat. Thus, in concern over public health and the economy, controlling the emergence of infectious diseases is critical worldwide. One of the ways to overcome the influences of antimicrobial resistance is by developing new, efficient, and improved antimicrobial agents. Medicinal plant-derived silver nanoparticles (AgNPs) are under intensive examination for a variety of therapeutic purposes and targeted applications in nanomedicine and nanotechnology. Plants belonging to the genus Thevetia [Syn. Casabela], which is known for its medicinal uses and has rarely been applied for the synthesis of AgNPs, is an attractive alternative as they have a high content of secondary metabolites. Herein, using aqueous leaf extract of Cascabela thevetia, which was locally found in the Makkah region, Saudi Arabia, green synthesis of AgNPs is reported. Active components of Cascabela thevetia aqueous leaf extract were sufficient to reduce AgNO3 into AgNPs and stabilize them as this was confirmed through UV-Visible absorption, Fourier transforms infrared (FTIR), X-ray diffraction (XRD), filed emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) studies. UV-Visible, HPLC, and FTIR analysis demonstrated the presence of gallic acid in aqueous extract and solution of C-AgNPs. The spherical Cascabela thevetia derived C-AgNPs with an average diameter in the range of 20–30 nm were highly dispersed, as seen from FESEM and TEM images, and demonstrated the high antibacterial and antifungal activities when incubated with Gram-positive bacteria Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus (S. aureus), Enterococcus faecalis (E. faecalis), Gram-negative bacteria Escherichia coli (E. coli), Salmonella typhimurium (S. typhimurium), Klebsiella pneumoniae (K. pneumoniae), Pseudomonas aeruginosa (P. aeruginosa) and fungi Candida albicans (C. albicans) and Candida parapsilosis (C. parapsilosis). The lowest MIC values of C-AgNPs versus S. aureus, E. faecalis, and E. coli were found. Finally, the antioxidant activity and catalytic property of C-AgNPs were assessed by neutralizing DPPH free radical and reducing methylene blue and rhodamine B dyes, respectively.

Rutin bioconjugates as potential nutraceutical prodrugs: An in vitro and in ovo toxicological screening

Rutin (RUT) is considered one the most attractive flavonoids from a therapeutic perspective due to its multispectral pharmacological activities including antiradical, anti-inflammatory, antiproliferative, and antimetastatic among others. Still, this compound presents a low bioavailability what narrows its clinical applications. To overcome this inconvenience, the current paper was focused on the synthesis, characterization, and toxicological assessment of two RUT bioconjugates obtained by enzymatic esterification with oleic acid (OA) and linoleic acid (LA)—rutin oleate (RUT-O) and rutin linoleate (RUT-L), as flavonoid precursors with improved physicochemical and biological properties. Following the enzymatic synthesis in the presence of Novozyme® 435, the two bioconjugates were obtained, their formation being confirmed by RAMAN and FT-IR spectroscopy. The in vitro and in ovo toxicological assessment of RUT bioconjugates (1–100 µM) was performed using 2D consecrated cell lines (cardiomyoblasts - H9c2(2-1), hepatocytes—HepaRG, and keratinocytes—HaCaT), 3D reconstructed human epidermis tissue (EpiDerm™), and chick chorioallantoic membranes, respectively. The results obtained were test compound, concentration—and cell-type dependent, as follows: RUT-O reduced the viability of H9c2(2-1), HepaRG, and HaCaT cells at 100 µM (to 77.53%, 83.17%, and 78.32%, respectively), and induced cell rounding and floating, as well as apoptotic-like features in the nuclei of all cell lines, whereas RUT-L exerted no signs of cytotoxicity in all cell lines in terms of cell viability, morphology, and nuclear integrity. Both RUT esters impaired the migration of HepaRG cells (at 25 µM) and lack irritative potential (at 100 µM) in vitro (tissue viability >50%) and in ovo (irritation scores of 0.70 for RUT-O, and 0.49 for RUT-L, respectively). Computational predictions revealed an increased lipophilicity, and reduced solubility, drug-likeness and drug score of RUT-O and RUT-L compared to their parent compounds—RUT, OA, and LA. In conclusion, we report a favorable toxicological profile for RUT-L, while RUT-O is dosage-limited since at high concentrations were noticed cytotoxic effects.

Molecular Mechanistic Pathways Targeted by Natural Compounds in the Prevention and Treatment of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and its prevalence is still growing rapidly. However, the efficient therapies for this kidney disease are still limited. The pathogenesis of DKD involves glucotoxicity, lipotoxicity, inflammation, oxidative stress, and renal fibrosis. Glucotoxicity and lipotoxicity can cause oxidative stress, which can lead to inflammation and aggravate renal fibrosis. In this review, we have focused on in vitro and in vivo experiments to investigate the mechanistic pathways by which natural compounds exert their effects against the progression of DKD. The accumulated and collected data revealed that some natural compounds could regulate inflammation, oxidative stress, renal fibrosis, and activate autophagy, thereby protecting the kidney. The main pathways targeted by these reviewed compounds include the Nrf2 signaling pathway, NF-κB signaling pathway, TGF-β signaling pathway, NLRP3 inflammasome, autophagy, glycolipid metabolism and ER stress. This review presented an updated overview of the potential benefits of these natural compounds for the prevention and treatment of DKD progression, aimed to provide new potential therapeutic lead compounds and references for the innovative drug development and clinical treatment of DKD.

Flavonols and Flavones as Potential anti-Inflammatory, Antioxidant, and Antibacterial Compounds

Plant preparations have been used to treat various diseases and discussed for centuries. Research has advanced to discover and identify the plant components with beneficial effects and reveal their underlying mechanisms. Flavonoids are phytoconstituents with anti-inflammatory, antimutagenic, anticarcinogenic, and antimicrobial properties. Herein, we listed and contextualized various aspects of the protective effects of the flavonols quercetin, isoquercetin, kaempferol, and myricetin and the flavones luteolin, apigenin, 3 $\prime$ ,4 $\prime$ -dihydroxyflavone, baicalein, scutellarein, lucenin-2, vicenin-2, diosmetin, nobiletin, tangeretin, and 5-O-methyl-scutellarein. We presented their structural characteristics and subclasses, importance, occurrence, and food sources. The bioactive compounds present in our diet, such as fruits and vegetables, may affect the health and disease state. Therefore, we discussed the role of these compounds in inflammation, oxidative mechanisms, and bacterial metabolism; moreover, we discussed their synergism with antibiotics for better disease outcomes. Indiscriminate use of antibiotics allows the emergence of multidrug-resistant bacterial strains; thus, bioactive compounds may be used for adjuvant treatment of infectious diseases caused by resistant and opportunistic bacteria via direct and indirect mechanisms. We also focused on the reported mechanisms and intracellular targets of flavonols and flavones, which support their therapeutic role in inflammatory and infectious diseases.

Flavonoids as regulators of TIMPs expression in cancer: Consequences, opportunities, and challenges

Cancer is one of the leading causes of death in patients worldwide, where invasion and metastasis are directly responsible for this statement. Although cancer therapy has progressed in recent years, current therapeutic approaches are ineffective due to toxicity and chemoresistance. Therefore, it is essential to evaluate other treatment options, and natural products are a promising alternative as they show antitumor properties in different study models. This review describes the regulation of tissue inhibitors of metalloproteinases (TIMPs) expression and the role of flavonoids as molecules with the antitumor activity that targets TIMPs therapeutically. These inhibitors regulate tissue extracellular matrix (ECM) turnover; they inhibit matrix metalloproteinases (MMPs), cell migration, invasion, and angiogenesis and induce apoptosis in tumor cells. Data obtained in cell lines and in vivo models suggest that flavonoids are chemopreventive and cytotoxic against various types of cancer through several mechanisms. Flavonoids also regulate crucial signaling pathways such as focal adhesion kinase (FAK), phosphatidylinositol-3-kinase (PI3K)-Akt, signal transducer and activator of transcription 3 (STAT3), nuclear factor κB (NFκB), and mitogen-activated protein kinase (MAPK) involved in cancer cell migration, invasion, and metastasis. All these data reposition flavonoids as excellent candidates for use in cancer therapy.

The impact of Nrf2/HO-1, caspase-3/Bax/Bcl2 and ATF6/IRE1/PERK/GRP78 signaling pathways in the ameliorative effects of morin against methotrexate-induced testicular toxicity in rats

BACKGROUND

Methotrexate (MT) is a broadly used chemotherapeutic drug however its clinical use is confronted with several forms of toxicities containing testicular damage. The current study assessed the ameliorative effects of morin on MT-induced testicular damage with the investigation of its mechanism and the potential involvement of oxidative stress, inflammation, apoptosis and endoplasmic reticulum stress in such protection.

METHODS

The animals were divided into 5 distinct groups (7 rats in each group). Group 1 was control group, group 2 received MT-only (20 mg/kg bw), group 3 received orally morin-only (100 mg/kg bw), group 4 received MT (20 mg/kg bw) + morin (50 mg/kg bw) and group 5 received MT (20 mg/kg bw) + morin (100 mg/kg). In this study, morin was administered orally for 10 days, while MT was administered intraperitoneally on the 5th day.

RESULTS

MT intoxication was linked with augmented MDA while decreased GSH levels, the enzyme activities of glutathione peroxidase, superoxide dismutase, and catalase and mRNA levels of HO-1 and Nrf2 in the testis tissues. MT injection caused inflammation in the testicular tissue via up-regulation of MAPK14, NFκB, TNF-α and IL-1β. MT application also caused apoptosis and endoplasmic reticulum stress in the testis tissue via increasing mRNA transcript levels of Bax, caspase-3, PERK, IRE1, ATF-6, GRP78 and down-regulation of Bcl-2.

CONCLUSION

Treatment with morin at a dose of 50 and 100 mg/kg considerably mitigated oxidative stress, inflammation, apoptosis and endoplasmic reticulum stress in the testicular tissue indicating that testicular damage related to MT toxicity could be modulated by morin administration.

Identification of Medicinal Compounds of Fagopyri Dibotryis Rhizome from Different Origins and Its Varieties Using UPLC-MS/MS-Based Metabolomics

Fagopyrum dibotrys, being native to southwest China, is widely distributed in Yunnan, Guizhou Provinces and Chongqing City. However, the quality of medicinal materials growing in different origins varies greatly, and cannot meet the market demand for high-quality F. dibotrys. In this study, 648 metabolites were identified, and phenolic compounds of F. dibotrys from different origins were clearly separated by principal component analysis (PCA). Our results suggested that the medicinal differences of F. dibotrys from different origins can be elucidated via the variations in the abundance of the phenolic and flavonoid compounds. We found that the epicatechin, total flavonoids and total tannin content in Yunnan Qujing (YQ) and Yunnan Kunming (YK) were higher than those in Chongqing Shizhu (CS), Chongqing Fuling (CF) and Guizhou Bijie (GB), suggesting that Yunnan Province can be considered as one of the areas that produce high-quality medicinal materials. Additionally, 1,6-di-O-galloyl-β-D-glucose, 2,3-di-O-galloyl-D-glucose and gallic acid could be used as ideal marker compounds for the quality control of F. dibotrys from different origins caused by metabolites, and the F. dibotrys planted in Yunnan Province is well worth exploiting.

Adding of Allium mongolicum regel extracts to lamb feedlot diets influences 4-alkyl-branched fatty acids deposition and the meat quality during storage

The present study aimed to investigate the effect of dietary supplementation with Allium mongolicum Regel extracts on the 4-alkyl-branched fatty acid deposition and meat quality during storage. Small-tailed Han sheep were divided into four groups (n = 15) and fed for 75 days with a basal diet (CK), CK supplemented with A. mongolicum Regel powder (AMR), A. mongolicum Regel water-soluble extract (AWE), or A. mongolicum Regel ethanol-soluble extract (AFE). The results revealed that both AMR and AWE diets decreased the 4-alkyl-branched fatty acids content in longissimus thoracis. Diet × storage time interactions were observed for acid value (AV), peroxidase (POx), glutathione peroxidase (GSH-Px), and total volatile base nitrogen (TVB-N). Patterns of change for AV, POx, and GSH-Px over time leading to the interactions were not readily apparent and changes were more governed by main effects. Dietary supplementation with AMR and AWE increased the total antioxidant capacity, total superoxide dismutase, and inhibited total bacteria counts compared to those in the CK lambs. The AWE diet also decreased the yellowness and hue angle. Overall, A. mongolicum Regel and its extracts could be used as a source of natural bioactive compounds in the lambs' diet to extend the storage time of their meat.

Enzymatic synthesis of novel unnatural phenoxodiol glycosides with a glycosyl donor flexible glycosyltransferase MeUGT1

Isoflavonoids are of great interest due to their human health-promoting properties, which have resulted in studies on exploiting these phytochemicals as hotspots in diverse bio -industries. Biocatalytic glycosylation of isoflavonoid aglycones to glycosides has attracted marked interests because it enable the biosynthesis of isoflavonoid glycosides with high selectivity under mild conditions, and also provide an environmentally friendly option for the chemical synthesis. Thus, these inspired us to exploit new flexible and effective glycosyltransferases from microbes for making glycosides attractive compounds that are in high demand in several industries. Most recently, we have reported the functional characterization of a bacterial-origin recombinant glycosyltransferase (MeUGT1). Herein, more detailed kinetic characteristics of this biocatalyst, using a number of glycosyl donor substrates, were examined for further investigation of its biocatalytic applicability, enabling it feasible to biosynthesize new glycosides; phenoxodiol-4'-O-α-glucuronide, phenoxodiol-4'-O-α-(2''-N-acetyl)glucosaminide, phenoxodiol-4'-O-α-galactoside, phenoxodiol-4'-O-α-(2''-N-acetyl)galactosaminide and phenoxodiol-4'-O-α-(2''-deoxy)glucoside. The thorough kinetic analyses revealed that while the recombinant enzyme can utilize, albeit with different substrate preference and catalytic efficiency, a total five different nucleotide sugars as glycosyl donors, exhibiting its promiscuity towards glycosyl donors. This is the first report that a recombinant glycosyltransferase MeUGT1 that can regio-specifically glycosylate C4'-hydroxyl function of semi-synthetic phenoxodiol isoflavene to biosynthesize a series of unnatural phenoxodiol-4'-O-α-glycosides.

Antithrombotic and antiplatelet effects of plant-derived compounds: a great utility potential for primary, secondary, and tertiary care in the framework of 3P medicine

Thromboembolism is the third leading vascular disease, with a high annual incidence of 1 to 2 cases per 1000 individuals within the general population. The broader term venous thromboembolism generally refers to deep vein thrombosis, pulmonary embolism, and/or a combination of both. Therefore, thromboembolism can affect both – the central and peripheral veins. Arterial thromboembolism causes systemic ischemia by disturbing blood flow and oxygen supply to organs, tissues, and cells causing, therefore, apoptosis and/or necrosis in the affected tissues. Currently applied antithrombotic drugs used, e.g. to protect affected individuals against ischemic stroke, demonstrate significant limitations. For example, platelet inhibitors possess only moderate efficacy. On the other hand, thrombolytics and anticoagulants significantly increase hemorrhage. Contextually, new approaches are extensively under consideration to develop next-generation antithrombotics with improved efficacy and more personalized and targeted application. To this end, phytochemicals show potent antithrombotic efficacy demonstrated in numerous in vitro, ex vivo, and in vivo models as well as in clinical evaluations conducted on healthy individuals and persons at high risk of thrombotic events, such as pregnant women (primary care), cancer, and COVID-19-affected patients (secondary and tertiary care). Here, we hypothesized that specific antithrombotic and antiplatelet effects of plant-derived compounds might be of great clinical utility in primary, secondary, and tertiary care. To increase the efficacy, precise patient stratification based on predictive diagnostics is essential for targeted protection and treatments tailored to the person in the framework of 3P medicine. Contextually, this paper aims at critical review toward the involvement of specific classes of phytochemicals in antiplatelet and anticoagulation adapted to clinical needs. The paper exemplifies selected plant-derived drugs, plant extracts, and whole plant foods/herbs demonstrating their specific antithrombotic, antiplatelet, and fibrinolytic activities relevant for primary, secondary, and tertiary care. One of the examples considered is antithrombotic and antiplatelet protection specifically relevant for COVID-19-affected patient groups.

Antioxidant Capacities and Enzymatic Inhibitory Effects of Different Solvent Fractions and Major Flavones from Celery Seeds Produced in Different Geographic Areas in China

To extend the application of celery (Apium graveolens L.) seeds, the antioxidant and enzymatic inhibitory activities of different fractions and their main flavones were investigated. The n-butanol fractions possessed the highest total phenolic content (TPC) and total flavonoid content (TFC) values. The n-butanol fractions from Northeast China samples exhibited the strongest free radical scavenging (DPPH IC₅₀ = 20.27 μg/mL, ABTS IC₅₀ = 15.11 μg/mL) and ferric reducing antioxidant power (FRAP 547.93 mg trolox (TE)/g) capacity, while those collected from Hubei China showed the optimal cupric reducing antioxidant capacity (CUPRAC) values (465.78 mg TE/g). In addition, the dichloromethane fractions from Jiangsu samples displayed a maximum Fe²⁺ chelating capacity (20.81 mg ethylene diamine tetraacetic acid (EDTA)/g). Enzyme level experiments indicated polyphenolic compounds might be the main hypoglycemic active components. Subsequently, the enzyme inhibitory activity of nine main flavones was evaluated. Chrysoeriol-7-O-glucoside showed better α-glucosidase inhibitory activity than others. However, apigenin showed the best inhibitory effect on α-amylases, while the presence of glycosides would reduce its inhibitory effect. This study is the first scientific report on the enzymatic inhibitory activity, molecular docking, and antioxidant capacity of celery seed constituents, providing a basis for treating or preventing oxidative stress-related diseases and hyperglycemia.

Potential Psychoactive Effects of Microalgal Bioactive Compounds for the Case of Sleep and Mood Regulation: Opportunities and Challenges

Sleep deficiency is now considered an emerging global epidemic associated with many serious health problems, and a major cause of financial and social burdens. Sleep and mental health are closely connected, further exacerbating the negative impact of sleep deficiency on overall health and well-being. A major drawback of conventional treatments is the wide range of undesirable side-effects typically associated with benzodiazepines and antidepressants, which can be more debilitating than the initial disorder. It is therefore valuable to explore the efficiency of other remedies for complementarity and synergism with existing conventional treatments, leading to possible reduction in undesirable side-effects. This review explores the relevance of microalgae bioactives as a sustainable source of valuable phytochemicals that can contribute positively to mood and sleep disorders. Microalgae species producing these compounds are also catalogued, thus creating a useful reference of the state of the art for further exploration of this proposed approach. While we highlight possibilities awaiting investigation, we also identify the associated issues, including minimum dose for therapeutic effect, bioavailability, possible interactions with conventional treatments and the ability to cross the blood brain barrier. We conclude that physical and biological functionalization of microalgae bioactives can have potential in overcoming some of these challenges.

The Impact of Plant Phytochemicals on the Gut Microbiota of Humans for a Balanced Life

The gastrointestinal tract of humans is a complex microbial ecosystem known as gut microbiota. The microbiota is involved in several critical physiological processes such as digestion, absorption, and related physiological functions and plays a crucial role in determining the host’s health. The habitual consumption of specific dietary components can impact beyond their nutritional benefits, altering gut microbiota diversity and function and could manipulate health. Phytochemicals are non-nutrient biologically active plant components that can modify the composition of gut microflora through selective stimulation of proliferation or inhibition of certain microbial communities in the intestine. Plants secrete these components, and they accumulate in the cell wall and cell sap compartments (body) for their development and survival. These compounds have low bioavailability and long time-retention in the intestine due to their poor absorption, resulting in beneficial impacts on gut microbiota population. Feeding diets containing phytochemicals to humans and animals may offer a path to improve the gut microbiome resulting in improved performance and/or health and wellbeing. This review discusses the effects of phytochemicals on the modulation of the gut microbiota environment and the resultant benefits to humans; however, the effect of phytochemicals on the gut microbiota of animals is also covered, in brief.

Biological Functions of Dillenia pentagyna Roxb. Against Pain, Inflammation, Fever, Diarrhea, and Thrombosis: Evidenced From in vitro, in vivo, and Molecular Docking Study

Dillenia pentagyna Roxb. is traditionally used to treat cancer, wound healing, diabetes, and diarrhea in local tribes. This study was designed to evaluate the pharmacological potentiality of this plant. In vivo analgesic, anti-inflammatory, and antipyretic studies of the methanol extracts of D. pentagyna (MEDP) leaves were performed by using acetic acid-induced nociception, formalin-induced paw licking, and yeast-induced pyrexia assay methods, respectively. In vivo antidiarrheal activity was carried out in mice by following castor oil-induced diarrhea and gastrointestinal transit manner. In vitro thrombolytic experiment was performed employing the clot lysis activity. Besides, a molecular docking study was performed by executing the software (PyRx, Discovery Studio, and UCSF Chimera). In the acetic acid-induced writhing study, MEDP possesses significant writhing inhibition in a dose-dependent manner. It showed 50.86% of maximum inhibition of pain in the case of MEDP at a dose of 400 mg/kg body weight. In the anti-inflammatory study, maximum inhibition rate was observed at a value of 59.98 and 41.29% in early and late phases, respectively, at the dose of 400 mg/kg body weight. In the case of yeast-induced hyperpyrexia, MEDP reduced hyperpyrexia in a dose-dependent manner. In the antidiarrheal assay, MEDP moderately inhibited the occurrence of diarrhea in all the experiments. In the thrombolytic study, a moderate (17.76%) clot lysis potency has been yielded by MEDP. Again, the molecular docking simulation revealed strong binding affinities with almost all the targeted proteins. The present study suggests that the MEDP possesses remarkable pharmacological activity and this finding validated the ethnobotanical significance of D. pentagyna as the source of pain, fever, and diarrhea management agent.

New Polymethoxyflavones from Hottonia palustris Evoke DNA Biosynthesis-Inhibitory Activity in An Oral Squamous Carcinoma (SCC-25) Cell Line

Four new compounds, 5-hydroxy-2′,6′-dimethoxyflavone (4), 5-hydroxy-2′,3′,6′-trimethoxyflavone (5), 5-dihydroxy-6-methoxyflavone (6), and 5,6′-dihydroxy-2′,3′-dimethoxyflavone (7), and three known compounds, 1,3-diphenylpropane-1,3-dione (1), 5-hydroxyflavone (2), and 5-hydroxy-2′-methoxyflavone (3), were isolated from the aerial parts of Hottonia palustris. Their chemical structures were determined through the use of spectral, spectroscopic and crystallographic methods. The quantitative analysis of the compounds (1–7) and the zapotin (ZAP) in methanol (HP1), petroleum (HP6), and two chloroform extracts (HP7 and HP8) were also determined using HPLC-PDA. The biological activity of these compounds and extracts on the oral squamous carcinoma cell (SCC-25) line was investigated by considering their cytotoxic effects using the MTT assay. Subsequently, the most active compounds and extracts were assessed for their effect on DNA biosynthesis. It was found that all tested samples during 48 h treatment of SCC-25 cells induced the DNA biosynthesis-inhibitory activity: compound 1 (IC₅₀, 29.10 ± 1.45 µM), compound 7 (IC₅₀, 40.60 ± 1.65 µM) and extracts ZAP (IC₅₀, 20.33 ± 1.01 µM), HP6 (IC₅₀, 14.90 ± 0.74 µg), HP7 (IC₅₀, 16.70 ± 0.83 µg), and HP1 (IC₅₀, 30.30 ± 1.15 µg). The data suggest that the novel polymethoxyflavones isolated from Hottonia palustris evoke potent DNA biosynthesis inhibitory activity that may be considered in further studies on experimental pharmacotherapy of oral squamous cell carcinoma.

Anti-Inflammatory and Antioxidant Capacity of a Fruit and Vegetable-Based Nutraceutical Measured by Urinary Oxylipin Concentration in a Healthy Population: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Oxylipins, lipid biomarkers of inflammation are considered the gold standard method to evaluate the inflammatory and antioxidant status. The aim of the present study was to investigate whether the administration of a polyphenolic extract shot in the form of a nutraceutical was able to reduce inflammation, measured in urine markers. Ninety-two participants (45 males, 47 females, age 34 ± 11 years, weight 73.10 ± 14.29 kg, height 1.72 ± 9 cm, BMI 24.40 ± 3.43 kg/m2) completed the study after an intervention of two 16-week periods consuming extract or placebo separated by a 4-week washout period. The results showed significant differences in terms of reduction of different pro-inflammatory oxylipins (15-keto-PGF2α (from 0.90 ± 0.25 ng/mL to 0.74 ± 0.19 ng/mL p < 0.05), ent-PGF2α (from 1.59 ± 0.37 ng/mL to 1.44 ± 0.32 ng/mL p < 0.05), 2,3-dinor-15-F2t-Isop) (from 1.17 ± 0.35 ng/mL to 1.02 ± 0.27 ng/mL p < 0.05), in total oxylipins count (from 8.03 ± 1.86 ng/mL to 7.25 ± 1.23 ng/mL p < 0.05), and increase in PGE2 (from 1.02 ± 0.38 ng/mL to 1.26 ± 0.38 ng/mL p < 0.05) which has an anti-inflammatory character, after extract consumption compared to placebo. The available data seem to indicate that long-term consumption of a nutraceutical with high polyphenol content improves inflammation and oxidation parameters measured in urine, through UHPLC-QqQ-ESI-MS/MS.

The consequence and mechanism of dietary flavonoids on androgen profiles and disorders amelioration

Androgen is a kind of steroid hormone that plays a vital role in reproductive system and homeostasis of the body. Disrupted androgen balance serves as the causal contributor to a series of physiological disorders and even diseases. Flavonoids, as an extremely frequent family of natural polyphenols, exist widely in plants and foods and have received great attention when considering their inevitable consumption and estrogen-like effects. Mounting evidence illustrates that flavonoids have a propensity to interfere with androgen synthesis and metabolism, and also have a designated improvement effect on androgen disorders. Therefore, flavonoids were divided into six subclasses based on the structural feature in this paper, and the literature about their effects on androgens published in the past ten years was summarized. It could be concluded that flavonoids have the potential to regulate androgen levels and biological effects, mainly by interfering with the hypothalamic-pituitary-gonadal axis, androgen synthesis and metabolism, androgen binding with its receptors and membrane receptors, and antioxidant effects. The faced challenges about androgen regulation by flavonoids masterly include target mechanism exploration, individual heterogeneity, food matrixes interaction, and lack of clinical study. This review also provides a scientific basis for nutritional intervention using flavonoids to improve androgen disorder symptoms.

Structure and Stability Characterization of Natural Lake Pigments Made from Plant Extracts and Their Potential Application in Polymer Composites for Packaging Materials

Natural dyes were extracted from various plant sources and converted into lake pigments based on aluminum and tin. Three different plants (weld, Persian berries, and Brazilwood) were chosen as representative sources of natural dyes. High-performance liquid chromatography (HPLC) and triple-quadrupole mass spectrometry (QqQ MS) were used to identify dyestuffs in the raw extracts. The natural dyes and lake pigments were further characterized by optical and scanning electron microscopy (SEM), UV-Vis spectrophotometry, and thermogravimetric analysis (TGA). The stabilization of the studied plant extracts onto aluminum and tin salts led to the formation of natural lake pigments characterized by different color shades. The natural lake pigments showed improved thermal and chemical stability, which was confirmed by their higher degradation temperatures and lower solubility in chemical agents compared to natural dyes extracted from plants. This improvement can be attributed to electrostatic attraction due to the process of chelation. Ethylene-norbornene (EN) composites colored with the lake pigments exhibited uniform color and improved resistance to long-term UV exposure aging. After 300 h of UV exposure, the aging factor of the neat EN copolymer reduced to 0.3, indicating an advanced aging process of polymer compared to colored samples. Prolonged UV exposure deteriorated the mechanical properties of EN by approximately 57%, compared to about 43% with the application of BW/Al lake pigment. Natural lake pigments could be used as effective substitutes for commercial colorants in plastics for packaging applications.

Centipeda minima: An update on its phytochemistry, pharmacology and safety

ETHNOPHARMACOLOGICAL RELEVANCE

Centipeda minima (CM), the dried whole plant of Centipeda minima (L.) A. Braun and Aschers, has been used as a traditional Chinese medicinal herb for thousands of years for the treatments of rhinitis, sinusitis, cough and asthmatic diseases. This review aimed to evaluate the therapeutic potential of CM by summarizing its phytochemistry, pharmacology, clinical application and safety.

METHODS

This review summarizes the published studies on CM in the Chinese Pharmacopoeia and literature databases including PubMed, Web of Science, Baidu Scholar, Wiley and China Knowledge Resource Integrated Database (CNKI), as well as the research articles on the phytochemistry, pharmacology, clinical application and safety of CM.

RESULTS

A total of 191 compounds have been isolated and identified from CM, including terpenes, flavonoids, sterols, phenols, organic acids and volatile oils. In addition, the pharmacological effects of CM, such as anti-cancer, anti-inflammatory and anti-bacterial activities, have also been evaluated by both in vitro and in vivo studies. The signaling pathways and mechanisms of action underlying the anti-cancer effects of CM have been revealed. Clinical applications of CM mainly include rhinitis and sinusitis, gynecological inflammation, cough, as well as asthma.

CONCLUSION

CM is a medicinal herb that possesses many therapeutic effects. Cutting-edge technology and system biology could provide us a more comprehensive understanding of the therapeutic effects, constituting components and toxicity of CM, which are the prerequisites for its translation into therapeutics for various disease treatments.

Total flavonoids of sea buckthorn (Hippophae rhamnoides L.) improve MC903-induced atopic dermatitis-like lesions

ETHNOPHARMACOLOGICAL RELEVANCE

Sea buckthorn (Hippophae rhamnoides L.) is popularly used as a herbal medicine and food additive in the world. Total flavonoids of Hippophae rhamnoides (TFH) are reported to have anti-inflammatory and immunomodulatory activities.

AIM

The effects of TFH on atopic dermatitis (AD)-like lesions induced by MC903 in mice was elucidated in the study.

METHODS

To induce AD-like lesions, MC903 was adopted to apply repeatedly on the left ear in C57BL/6 mice. After induction of AD-like lesions, 0.5% and 1% TFH cream was applied topically on ears of mice once a day for 8 days. The degree of skin lesions was evaluated by macroscopical and histological methods. Expressions of filaggrin (FLG) was evaluated by Western blotting. Real-time polymerase chain reaction (qPCR) was adopted to detect the mRNA expression of thymic stromal lymphopoietin (TSLP), interferon (IFN)-γ, interleukin (IL-4), tumor necrosis factor (TNF)-α in skin lesions. In vitro, Cytokine Antibody Arrays were performed to measure production of cytokines in IFN-γ/TNF-α-treated HaCaT cells, Western blotting was employed to detect the expressions of p-NF-κB, p-ERK and p-P38.

RESULTS

Topical application of TFH significantly improved the severity of dermatitis by inhibiting the infiltration of mast cell, increasing expression of FLG, decreasing the expressions of TNF-α, IL-4, IFN-γ and TSLP in skin lesions. TFH decreased the levels of IL-1α, IL-1β, IL-6, monocyte chemoattractant protein (MCP)-1, MCP-3, macrophage-derived chemokine (MDC), platelet-derived growth factor (PDGF)-BB, thymus and activation regulated chemokine (TARC) in the supernatants of the HaCaT cells treated by IFN-γ/TNF-α. Furthermore, expressions of p-NF-κB, p-ERK and p-P38 were also decreased by TFH administration with dose dependent manner in HaCaT cells treated by IFN-γ/TNF-α.

CONCLUSIONS

Topical application of TFH improved AD-like lesions in mice induced by MC903. Which exerted the effects of anti-inflammation and repairing skin barrier by regulating Th1/Th2 balance. This finding indicates that TFH is a novel potential agent for the external treatment of AD.

Antioxidant and Enzyme Inhibitory Properties, and HPLC–MS/MS Profiles of Different Extracts of Arabis carduchorum Boiss.: An Endemic Plant to Turkey

In this study, six extracts of Arabis carduchorum prepared from solvents of varying polarity (water, methanol, ethyl acetate, dichloromethane, and n-hexane) were investigated for their chemical profiles and total phenolic and flavonoid contents (TPC/TFC) using HPLC–MS/MS and spectrophotometric/colorimetric assays, respectively, along with the assessment of their antioxidant and enzyme inhibitory effects. In general, the polar extracts (methanol, water, and infusion) showed higher TPC/TFC than the other extracts (range:13.73–26.62 mg GAE/g; 2.66–52.95 mg RE/g, respectively). The total antioxidant capacity of the polar extracts ranged from 0.90–1.85 mmol TE/g in phosphomolybdenum assay, while the free radical scavenging potential ranged from 4.36–32.13 mg TE/g and 12.58–67.73 mg TE/g in DPPH and ABTS assays, respectively. While the water and infuse extract inhibited only butyrylcholinesterase (2.68 and 2.39 mg GALAE/g, respectively), the other extracts were found to inhibit both acetyl- and butyryl-cholinesterases (0.96–2.73 mg GALAE/g and 1.86–5.11 mg GALAE/g, respectively). On the contrary, all extracts exhibited anti-tyrosinase (40.24–59.22 mg KAE/g) and anti-amylase (0.09–0.63 mmol ACAE/g) activities. Overall, this study highlighted the effect of solvent polarity on the extraction of bioactive compounds and the biological properties of the extracts of A. carduchorum; hence, the results obtained could be used to guide optimum extraction in future studies.

Chemical Profiling of Limonium vulgare Mill. Using UHPLC-DAD-ESI/MS2 and GC-MS Analysis

Limonium vulgare Mill. is a plant growing widely in harsh environments, such as salt marshes, for which a chemical profile is still unknown, although some interesting bioactivities were already reported. So, this halophyte chemical profile must be established to find the possible bioactive compounds, valorize the species, and contribute to the salt marsh’s exploitation. This work set the chemical profile of L. vulgare’s aerial parts (leaves and inflorescences) using UHPLC-DAD-ESI/MS2 and GC-MS analysis. The lipophilic profile showed a richness in fatty acids, alkanes, and terpenoids, β-sitosterol being the major compound in inflorescences in the fruiting stage (0.822 ± 0.015 mg/g of the dry plant) and leaves (0.534 ± 0.017 mg/g of the dry plant). In contrast, in the inflorescences in the flowering stage, the major compound is nonacosane (0.228 ± 0.001 mg/g of the dry plant). The polyphenolic profile demonstrates that L. vulgare produces several flavonoids from which quercetin and myricetin can be highlighted; in particular, myricetin derivatives are prevalent in all extracts. Amongst the flavonoids, myricetin 3-rhamnoside is the most abundant in the inflorescences in the flowering stage (6.35 ± 0.05 mg/g of the dry plant), myricetin in leaves (9.69 ± 0.11 mg/g of the dry plant), and in the inflorescences in the fruiting stage baicalin presents the highest amount (5.15 ± 0.07 mg/g of the dry plant). This is the first report on L. vulgare’s chemical profile and the results indicate that this species is an exciting source of bioactive compounds, suggesting it has a use to produce nutraceuticals and/or pharmaceuticals.

Flavonoids a Bioactive Compound from Medicinal Plants and Its Therapeutic Applications

Plants generally secrete secondary metabolites in response to stress. These secondary metabolites are very useful for humankind as they possess a wide range of therapeutic activities. Secondary metabolites produced by plants include alkaloids, flavonoids, terpenoids, and steroids. Flavonoids are one of the classes of secondary metabolites of plants found mainly in edible plant parts such as fruits, vegetables, stems, grains, and bark. They are synthesized by the phenylpropanoid pathway. Flavonoids possess antibacterial, antiviral, antioxidant, anti-inflammatory, antimutagenic, and anticarcinogenic properties. Due to their various therapeutic applications, various pharmaceutical companies have exploited different plants for the production of flavonoids. To overcome this situation, various biotechnological strategies have been incorporated to improve the production of different types of flavonoids. In this review, we have highlighted the various types of flavonoids, their biosynthesis, properties, and different strategies to enhance the production of flavonoids.

Effects of Fermented Herbal Tea Residue on Serum Indices and Fecal Microorganisms of Chuanzhong Black Goats

Herbal tea residues (HTRs) are a by−product of herbal tea processing that contains many nutrients and active substances but are often discarded as waste. The main aim of the present study was to determine the food safety of HTRs and lay the foundation for its use as a novel feed resource for goats. In this study, discarded HTRs were fermented and then fed to 33 female Chuanzhong black goats (121 ± 4.00 days) with similar weight (9.33 ± 0.95 kg) and genetic background, which were divided into three groups (fermented herbal tea residue (FHTR) replacement of 0%, 15% and 30% of the forage component of the diet). The feeding experiment lasted for 35 days. On day 35, our findings indicated that the concentrations of hydroxyl radicals and urea increased linearly, and the concentrations of glutathione peroxidase increased quadratically with the increase in FHTR. In addition, we investigated the fecal microbiota composition of eight Chuanzhong black goats in the control, 15% and 30% FHTR replacement groups and found that FHTR had no remarkable effect on the fecal microbiota composition. Results indicated that goat physiological functions remained stable after FHTR was added to the diet.

Antioxidant and DNA-Protective Potentials, Main Phenolic Compounds, and Microscopic Features of Koelreuteria paniculata Aerial Parts

Interest in plant extracts as a natural source of antioxidants has grown significantly in recent years. The tree species Koelreuteria paniculata deserves attention due to its wide distribution, good adaptability, and growth to the degree of invasiveness in a number of European countries. The purpose of the present study was to analyze flavonoids and phenolic acids of the ethanol extracts from aerial parts of K. paniculata and to screen their antioxidant and DNA-protective activity. HPLC profiling revealed the presence of five flavonoids, with rutin (4.23 mg/g DW), hesperidin (2.97 mg/g DW), and quercetin (2.66 mg/g DW) as the major ones in the leaves, and (−)-epicatechin (2.69 mg/g DW) in the flower buds. Among the nine phenolic acids identified, rosmarinic, p-coumaric, salicylic, vanillic, and gallic acids were the best represented. All the extracts tested showed in vitro antioxidant activity that was determined by DPPH, ABTS, FRAP, and CUPRAC assays. The highest activity was recorded in the flower parts (in the range from 1133 to 4308 mmol TE/g DW). The DNA-protective capacity of the flower and stem bark extracts from the in vitro nicking assay performed, as well as the main diagnostic microscopic features of the plant substances, are given for the first time. According to the results obtained, the aerial parts of K. paniculata could be valuable sources of natural antioxidants.

Hesperidin: A Review on Extraction Methods, Stability and Biological Activities

Hesperidin is a bioflavonoid occurring in high concentrations in citrus fruits. Its use has been associated with a great number of health benefits, including antioxidant, antibacterial, antimicrobial, anti-inflammatory and anticarcinogenic properties. The food industry uses large quantities of citrus fruit, especially for the production of juice. It results in the accumulation of huge amounts of by-products such as peels, seeds, cell and membrane residues, which are also a good source of hesperidin. Thus, its extraction from these by-products has attracted considerable scientific interest with aim to use as natural antioxidants. In this review, the extraction and determination methods for quantification of hesperidin in fruits and by-products are presented and discussed as well as its stability and biological activities.

Glycosylation of Methylflavonoids in the Cultures of Entomopathogenic Filamentous Fungi as a Tool for Obtaining New Biologically Active Compounds

Flavonoid compounds are secondary plant metabolites with numerous biological activities; they naturally occur mainly in the form of glycosides. The glucosyl moiety attached to the flavonoid core makes them more stable and water-soluble. The methyl derivatives of flavonoids also show increased stability and intestinal absorption. Our study showed that such flavonoids can be obtained by combined chemical and biotechnological methods with entomopathogenic filamentous fungi as glycosylation biocatalysts. In the current paper, two flavonoids, i.e., 2′-hydroxy-4-methylchalcone and 4′-methylflavone, have been synthesized and biotransformed in the cultures of two strains of entomopathogenic filamentous fungi Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5. Biotransformation of 2′-hydroxy-4-methylchalcone resulted in the formation of two dihydrochalcone glucopyranoside derivatives in the culture of I. fumosorosea KCH J2 and chalcone glucopyranoside derivative in the case of B. bassiana KCH J1.5. 4′-Methylflavone was transformed in the culture of I. fumosorosea KCH J2 into four products, i.e., 4′-hydroxymethylflavone, flavone 4′-methylene-O-β-d-(4″-O-methyl)-glucopyranoside, flavone 4′-carboxylic acid, and 4′-methylflavone 3-O-β-d-(4″-O-methyl)-glucopyranoside. 4′-Methylflavone was not efficiently biotransformed in the culture of B. bassiana KCH J1.5. The computer-aided simulations based on the chemical structures of the obtained compounds showed their improved physicochemical properties and antimicrobial, anticarcinogenic, hepatoprotective, and cardioprotective potential.

Inhibition of Dipeptidyl Peptidase-4 by Flavonoids: Structure–Activity Relationship, Kinetics and Interaction Mechanism

With the aim to establish a structure-inhibitory activity relationship of flavonoids against dipeptidyl peptidase-4 (DPP-4) and elucidate the interaction mechanisms between them, a pannel of 70 structurally diverse flavonoids was used to evaluate their inhibitory activities against DPP-4, among which myricetin, hyperoside, narcissoside, cyanidin 3-O-glucoside, and isoliquiritigenin showed higher inhibitory activities in a concentration-dependent manner. Structure-activity relationship analysis revealed that introducing hydroxyl groups to C3', C4', and C6 of the flavonoid structure was beneficial to improving the inhibitory efficacy against DPP-4, whereas the hydroxylation at position 3 of ring C in the flavonoid structure was unfavorable for the inhibition. Besides, the methylation of the hydroxyl groups at C3', C4', and C7 of the flavonoid structure tended to lower the inhibitory activity against DPP-4, and the 2,3-double bond and 4-carbonyl group on ring C of the flavonoid structure was essential for the inhibition. Glycosylation affected the inhibitory activity diversely, depending on the structure of flavonoid aglycone, type of glycoside, as well as the position of substitution. Inhibition kinetic analysis suggested that myricetin reversibly inhibited DPP-4 in a non-competitive mode, whereas hyperoside, narcissoside, cyanidin 3-O-glucoside, and isoliquiritigenin all reversibly inhibited DPP-4 in a mixed type. Moreover, the fluorescence quenching analysis indicated that all the five flavonoid compounds could effectively quench the intrinsic fluorescence of DPP-4 by spontaneously binding with it to form an unstable complex. Hydrogen bonds and van der Waals were the predominant forces to maintain the complex of myricetin with DPP-4, and electrostatic forces might play an important role in stabilizing the complexes of the remaining four flavonoids with DPP-4. The binding of the tested flavonoids to DPP-4 could also induce the conformation change of DPP-4 and thus led to inhibition on the enzyme. Molecular docking simulation further ascertained the binding interactions between DPP-4 and the selected five flavonoids, among which hyperoside, narcissoside, cyaniding 3-O-glucoside, and isoliquiritigenin inserted into the active site cavity of DPP-4 and interacted with the key amino acid residues of the active site, whereas the binding site of myricetin was located in a minor cavity close to the active pockets of DPP-4.

4'-Methylflavanone Glycosides Obtained Using Biotransformation in the Entomopathogenic Filamentous Fungi Cultures as Potential Anticarcinogenic, Antimicrobial, and Hepatoprotective Agents

Flavonoid compounds exhibit numerous biological activities and significantly impact human health. The presence of methyl or glucosyl moieties attached to the flavonoid core remarkably modifies their physicochemical properties and improves intestinal absorption. Combined chemical and biotechnological methods can be applied to obtain such derivatives. In the presented study, 4'-methylflavanone was synthesized and biotransformed in the cultures of three strains of entomopathogenic filamentous fungi, i.e., Isaria fumosorosea KCH J2, Beauveria bassiana KCH J1.5, and Isaria farinosa KCH J2.1. The microbial transformation products in the culture of I. fumosorosea KCH J2, flavanone 4'-methylene-O-β-D-(4″-O-methyl)-glucopyranoside, 2-phenyl-(4'-hydroxymethyl)-4-hydroxychromane, and flavanone 4'-carboxylic acid were obtained. Biotransformation of 4'-methylflavanone in the culture of B. bassiana KCH J1.5 resulted in the formation of one main product, i.e., flavanone 4'-methylene-O-β-D-(4″-O-methyl)-glucopyranoside. In the case of I. farinosa KCH J2.6 as a biocatalyst, three products, i.e., flavanone 4'-methylene-O-β-D-(4″-O-methyl)-glucopyranoside, flavanone 4'-carboxylic acid, and 4'-hydroxymethylflavanone 4-O-β-D-(4″-O-methyl)-glucopyranoside were obtained. The Swiss-ADME online simulations confirmed the increase in water solubility of 4'-methylflavanone glycosides and analyses performed using the Way2Drug Pass Online prediction tool indicated that flavanone 4'-methylene-O-β-D-(4″-O-methyl)-glucopyranoside and 4'-hydroxymethylflavanone 4-O-β-D-(4″-O-methyl)-glucopyranoside, which had not been previously reported in the literature, are promising anticarcinogenic, antimicrobial, and hepatoprotective agents.

Biotransformation of Liquiritigenin into Characteristic Metabolites by the Gut Microbiota

The bioavailability of flavonoids is generally low after oral administration. The metabolic transformation of flavonoids by the gut microbiota may be one of the main reasons for this, although these metabolites have potential pharmacological activities. Liquiritigenin is an important dihydroflavonoid compound found in Glycyrrhiza uralensis that has a wide range of pharmacological properties, such as antitumor, antiulcer, anti-inflammatory, and anti-AIDS effects, but its mechanism of action remains unclear. This study explored the metabolites of liquiritigenin by examining gut microbiota metabolism and hepatic metabolism in vitro. Using LC-MS/MS and LC/MSⁿ-IT-TOF techniques, three possible metabolites of liquiritigenin metabolized by the gut microbiota were identified: phloretic acid (M3), resorcinol (M4), and M5. M5 is speculated to be davidigenin, which has antitumor activity. By comparing these two metabolic pathways of liquiritigenin (the gut microbiota and liver microsomes), this study revealed that there are three main metabolites of liquiritigenin generated by intestinal bacteria, which provides a theoretical basis for the study of pharmacologically active substances in vivo.

The role of plant-derived natural antioxidants in reduction of oxidative stress

Free radicals are a group of damaging molecules produced during the normal metabolism of cells in the human body. Exposure to ultraviolet radiation, cigarette smoking, and other environmental pollutants enhances free radicals in the human body. The destructive effects of free radicals may also cause harm to membranes, enzymes, and DNA, leading to several human diseases such as cancer, atherosclerosis, malaria, coronavirus disease (COVID-19), rheumatoid arthritis, and neurodegenerative illnesses. This process occurs when there is an imbalance between free radicals and antioxidant defenses. Since antioxidants scavenge free radicals and repair damaged cells, increasing the consumption of fruits and vegetables containing high antioxidant values is recommended to slow down oxidative stress in the body. Additionally, natural products demonstrated a wide range of biological impacts such as anti-inflammatory, anti-aging, anti-atherosclerosis, and anti-cancer properties. Hence, in this review article, our goal is to explore the role of natural therapeutic antioxidant effects to reduce oxidative stress in the diseases.

Anticancer Activities of Polygonum odoratum Lour.: A Systematic Review

Cancers are a potential cause of death worldwide and represent a massive burden for healthcare systems. Treating cancers requires substantial resources, including skilled personnel, medications, instruments, and funds. Thus, developing cancer prevention and treatment measures is necessary for healthcare personnel and patients alike. P. odoratum (Polygonaceae family) is a plant used as a culinary ingredient. It exhibits several pharmacological activities, such as antibacterial, antifungal, antioxidant, anti-inflammatory, and anticancer. Several classes of phytochemical constituents of P. odoratum have been reported. The important ones might be polyphenol and flavonoid derivatives. In this systematic review, the activities of P. odoratum against cancerous cells were determined and summarized. Data were obtained through a systematic search of electronic databases (EMBASE, PubMed, Scopus, Thai Thesis Database, Science Direct and Clinical Key). Eight studies met the eligibility criteria. The cancerous cell lines used in the studies were lymphoma, leukemia, oral, lung, breast, colon, and liver cancer cells. Based on this review, P. odoratum extracts significantly affected Epstein-Barr virus (EBV) genome-carrying human lymphoblastoid (Raji), mouse lymphocytic leukemia (P388), human acute lymphocytic leukemia (Jurkat), breast adenocarcinoma (MCF-7), human colon adenocarcinoma (HT-29), human T lymphoblast (MOLT-4), human promyelocytic leukemia cell line (HL-60), human hepatocellular carcinoma (HepG2), and oral squamous cell carcinoma (SAS, SCC-9, HSC-3) through induction of cell apoptosis, arrest of the cell cycle, inhibition of cell proliferation, migration, and colonization. The molecular mechanism of P. odoratum against cancers was reported to involve suppressing essential proteins required for cell proliferation, colonization, migration, apoptosis, and angiogenesis. They were survivin, cyclin-D, cyclooxygenase 2 (COX-2), matrix metalloproteinase-9 (MMP-9), and vascular endothelial growth factor A (VEGF-A). The extract of P. odoratum was also involved in the protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway by inhibiting the expression of Akt, phosphorylated Akt, mTOR, and phosphorylated mTOR. From the key results of this review, P. odoratum is a promising chemotherapy and chemopreventive agent. Further investigation of its pharmacological activity and mechanism of action should be conducted using standardized extracts. In vivo experiments and clinical trials are required to confirm the anticancer activity.

Kaempferol: A flavonoid with wider biological activities and its applications

Kaempferol and its derivatives are naturally occurring phytochemicals with promising bioactivities. This flavonol can reduce the lipid oxidation in the human body, prevent the organs and cell structure from deterioration and protect their functional integrity. This review has extensively highlighted the antioxidant, antimicrobial, anticancer, neuroprotective, and hepatoprotective activity of kaempferol. However, poor water solubility and low bioavailability of kaempferol greatly limit its applications. The utilization of advanced delivery systems can improve its stability, efficacy, and bioavailability. This is the first review that aimed to comprehensively collate some of the vital information published on biosynthesis, mechanism of action, bioactivities, bioavailability, and toxicological potential of kaempferol. Besides, it provides insights into the future direction on the improvement of bioavailability of kaempferol for wide applications.

COVID-19 Crisis, Herbal Medicines, and Natural Products - Concerns and Suggestions

: Since the outbreak of the COVID-19 pandemic in the last days of 2019 in China, medical experts and organizations worldwide have proposed guidelines for its prevention and treatment. However, despite the availability of state-of-the-art technologies, modern medicine specialists have so far not been successful in controlling it. This has led traditional medicine experts to propagate their knowledge to prevent and cure COVID-19, creating an open debate. According to scientific literature, traditional medicine experts claim beneficial effects of herbal medicines against viral infections and their effectiveness in controlling the symptoms of respiratory disorders. Modern medicine specialists express their concerns about the quality, safety, and efficacy of herbal medicines, in addition to the risk of herb-drug interactions and the lack of randomized clinical studies. Herbal medicines have been popular since prehistoric times, and during the COVID-19 pandemic, they are increasingly used worldwide. The lack of definite cure and the high cost of available modern medicines have also promoted the use of herbal medicines. An evidence-based approach using herbal medicines with proven antiviral activities or containing compounds providing symptomatic relief in COVID-19 can be considered for clinical studies. The interaction of herbal medicines with modern drugs should also be considered in patients taking them. Traditional and modern medicine aim to provide effective and safe treatment and prevent COVID-19 infection. Considering the ground realities of the COVID-19 crisis and keeping in view the worldwide use of herbal medicines, in our opinion, the pros and cons of their use should be carefully weighed, and practical solutions should be considered.

Therapeutic Efficacy of Flavonoids in Allergies: A Systematic Review of Randomized Controlled Trials

Objective. To assess the clinical efficacy of flavonoid supplements on allergic diseases. Design. Systematic review. Data Sources. MEDLINE/PubMed, Scopus, Web of Science, and Embase databases were searched from inception to September 2021. Eligibility Criteria for Selecting Studies. Eligible study designs were randomized controlled trials that investigated the effect of flavonoids applied to allergic diseases. Results. This review included 15 randomized controlled trials, including allergic rhinitis/cedar pollinosis ( $n=10$ ), asthma ( $n=3$ ), and atopic dermatitis ( $n=2$ ). A total of 990 participants aged 6 to 69 years were included in these studies. Globally, 12 studies (80%) revealed some benefits of flavonoids (isolate or combined with other compounds) in allergic patients, while three studies (20%) reported no statistically significant impact on symptom scores and/or lung function. No severe adverse events related to treatment were reported. According to the GRADE system, the outcomes evaluated were of low to moderate quality of evidence. Conclusions. Overall, this review suggests that the administration of flavonoids may provide a viable strategy for mitigating allergic symptoms. Future trials with high methodological quality are needed to establish definitive conclusions. This trial is registered with PROSPERO registration no. CRD42021237403.

Identification and Characterization of Two Bibenzyl Glycosyltransferases from the Liverwort Marchantia polymorpha

Liverworts are rich in bibenzyls and related O-glycosides, which show antioxidant activity. However, glycosyltransferases that catalyze the glycosylation of bibenzyls have not yet been characterized. Here, we identified two bibenzyl UDP-glucosyltransferases named MpUGT737B1 and MpUGT741A1 from the model liverwort Marchantia polymorpha. The in vitro enzymatic assay revealed that MpUGT741A1 specifically accepted the bibenzyl lunularin as substrate. MpUGT737B1 could accept bibenzyls, dihydrochalcone and phenylpropanoids as substrates, and could convert phloretin to phloretin-4-O-glucoside and phloridzin, which showed inhibitory activity against tyrosinase and antioxidant activity. The results of sugar donor selectivity showed that MpUGT737B1 and MpUGT741A1 could only accept UDP-glucose as a substrate. The expression levels of these MpUGTs were considerably increased after UV irradiation, which generally caused oxidative damage. This result indicates that MpUGT737B1 and MpUGT741A1 may play a role in plant stress adaption. Subcellular localization indicates that MpUGT737B1 and MpUGT741A1 were expressed in the cytoplasm and nucleus. These enzymes should provide candidate genes for the synthesis of bioactive bibenzyl O-glucosides and the improvement of plant antioxidant capacity.

The Phenolics and Antioxidant Properties of Black and Purple versus White Eggplant Cultivars

The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhibitory activity of black (Aydin Siyahi), purple (Kadife Kemer) and white (Trabzon Kadife) eggplants grown in Turkey were subjected to a comparative investigation. The black cultivar exhibited the highest total phenolic (17,193 and 6552 mg gallic acid equivalent/kg fw), flavonoid (3019 and 1160 quercetin equivalent/kg fw) and anthocyanin (1686 and 6167 g delphinidin-3-O-glucoside equivalent/kg fw) contents in crude extracts of the peel and pulp. The majority of the caffeic acid was identified in the ester (2830 mg/kg fw) and ester-bound (2594 mg/kg fw) forms in the peel of ‘Kadife Kemer’ and in the glycoside form (611.9 mg/kg fw) in ‘Aydin Siyahi’, as well as in the pulp of these two eggplants. ‘Kadife Kemer’ (purple eggplant) contained the majority of the chlorogenic acid in free form (27.55 mg/kg fw), compared to ‘Aydin Siyahi’ in the ester (7.82 mg/kg fw), glycoside (294.1 mg/kg dw) and ester-bound (2.41 mg/kg fw) forms. The eggplant cultivars (peel and pulp, mg/kg fw) exhibited a relatively high delphinidin-3-O-rutinoside concentration in the peel of ‘Aydin Siyahi’ (avg. 1162), followed by ‘Kadife Kemer’ (avg. 336.6), and ‘Trabzon Kadife’ (avg. 215.1). The crude phenolic extracts of the eggplants exhibited the highest antioxidant capacity values (peel and pulp, µmoL Trolox equivalent/kg fw) of 2,2-diphenyl-1-picrylhydrazyl (DPPH, 8156 and 2335) and oxygen radical absorbance capacity (ORAC, 37,887 and 17,648). The overall results indicate that black and purple eggplants are the cultivars with greater potential benefits in terms of their phenolics and antioxidant values than the white eggplant.

A comprehensive and current review on the role of flavonoids in lung cancer-Experimental and theoretical approaches

BACKGROUND

It is well-known that flavonoids, which can be easily obtained from many fruits and vegetables are widely preferred in the treatment of some important diseases. Some researchers noted that these chemical compounds exhibit high inhibition effect against various cancer types. Many experimental studies proving this ability of the flavonoids with high antioxidant activity are available in the literature.

PUROPOSE

The main aim of this review is to summarize comprehensively anticancer properties of flavonoids against the lung cancer in the light of experimental studies and well-known theory and electronic structure principles. In this review article, more detailed and current information about the using of flavonoids in the treatment of lung cancer is presented considering theoretical and experimental approaches.

STUDY DESIGN

In addition to experimental studies including the anticancer effects of flavonoids, we emphasized the requirement of the well-known electronic structure principle in the development of anticancer drugs. For this aim, Conceptual Density Functional Theory should be considered as a powerful tool. Searching the databases including ScienceDirect, PubMed and Web of Science, the suitable reference papers for this project were selected.

METHODS

Theoretical tools like DFT and Molecular Docking provides important clues about anticancer behavior and drug properties of molecular systems. Conceptual Density Functional Theory and CDFT based electronic structure principles and rules like Hard and Soft Acid-Base Principle (HSAB), Maximum Hardness Principle, Minimum Polarizability, Minimum Electrophilicity Principles and Maximum Composite Hardness Rule introduced by one of the authors of this review are so useful to predict the mechanisms and powers of chemical systems. Especially, it cannot be ignored the success of HSAB Principle in the explanations and highlighting of biochemical interactions.

RESULTS

Both theoretical analysis and experimental studies confirmed that flavonoids have higher inhibition effect against lung cancer. In addition to many superior properties like anticancer activity, antimicrobial activity, antioxidant activity, antidiabetic effect of flavonoids, their toxicities are also explained with the help of published popular papers. Action modes of the mentioned compounds are given in detail.

CONCLUSION

The review includes detailed information about the mentioned electronic structure principles and rules and their applications in the cancer research. In addition, the epidemiology and types of lung cancer anticancer activity of flavonoids in lung cancer are explained in details.

The Influence of Chlorpyrifos on the Nonenzymatic Antioxidants Content in Macrophytes Leaves

Water pollution can be moved or limited by macrophytes in a phytoremediation process. The presence of insecticides in the plant life environment may affect physiological processes and contribute to the formation of secondary oxidative stress in plant tissues. To protect against oxidative stress, macrophytes have developed a system of mechanisms consisting of nonenzymatic and enzymatic antioxidants. The influence of various concentrations of chlorpyrifos on the nonenzymatic system in Canadian waterweed (Elodea canadensis Michx.), needle spikerush (Eleocharis acicularis) and water mint (Mentha aquatica L.) was studied. The differences in the value of the total concentration of polyphenols and flavonoids, as well as analysis of chlorophyll-a, chlorophyll-b, anthocyanin and carotenoid concentrations were determined in leaves. Research indicated a significant increase in the content of polyphenols and flavonoids in a solution with the highest concentration of chlorpyrifos while the opposite tendency was observed after analyses of the main assimilating pigments of plant tissues. It was concluded that aqueous plants exposed to toxic insecticide molecules created a defensive mechanism by nonenzymatic antioxidant systems and the amount of low-molecular weight compounds depended on the pollutant concentration which influenced biosynthesis mechanisms in plant cells.

Artichoke and bergamot extracts: a new opportunity for the management of dyslipidemia and related risk factors

The relationship between low LDL-C (cholesterol associated with low-density lipoprotein) and a lower relative risk of developing cardiovascular disease (CVD) has been widely demonstrated. Although from a pharmacological point of view, statins, ezetimibe and PCSK inhibitors, alone or in combination are the front and center of the therapeutic approaches for reducing LDL-C and its CV consequences, in recent years nutraceuticals and functional foods have increasingly been considered as a valid support in the reduction of LDL-C, especially in patients with mild/moderate hyperlipidemia - therefore not requiring pharmacological treatment - or in patients intolerant to statins or other drugs. An approach also shared by the European Atherosclerosis Society (EAS). Of the various active ingredients with hypolipidemic properties, we include the artichoke (Cynara cardunculus, Cynara scolymus) and the bergamot (Citrus bergamia) which, thanks essentially to the significant presence of polyphenols in their extracts, can exert this action associated with a number of other complementary inflammation and oxidation benefits. In light of these evidence, this review aimed to describe the effects of artichoke and bergamot in modifying the lipid and inflammatory parameters described in in vitro, in vivo and clinical studies. The available data support the use of standardized compositions of artichoke and bergamot extracts, alone or in combination, in the treatment of mild to moderate dyslipidemia, in patients suffering from metabolic syndrome, hepatic steatosis, or intolerant to common hypolipidemic treatments.

Metabonomics Analysis of Stem Extracts from Dalbergia sissoo

Dalbergia sissoo is a woody plant with economic and medicinal value. As the pharmacological qualities and properties of the wood from this plant primarily depend on its extractives, in this study, the metabolomic analysis of extractives from its stems was carried out using UPLC-MS/MS. A total of 735 metabolites were detected from two groups of samples, heartwood and sapwood, with the largest number of terpenoids in type and the largest number of flavonoids in quantity. The PCA and cluster analysis showed significant differences in the metabolite composition between the two groups. The differential metabolites were mainly organic oxygen compounds, flavonoids, and isoflavones. Among the 105 differential metabolites, 26 metabolites were significantly higher in relative content in sapwood than in heartwood, while the other 79 metabolites were significantly higher in relative content in heartwood than in sapwood. KEGG metabolic pathway enrichment analysis showed that these differential metabolites were mainly enriched in three metabolic pathways: Flavonoid biosynthesis, isoflavonoid biosynthesis, and flavonoid and flavonol biosynthesis. This study provides a reference for metabolomics studies in Dalbergia and other woody plants.

Flavonoids Target Human Herpesviruses That Infect the Nervous System: Mechanisms of Action and Therapeutic Insights

Human herpesviruses (HHVs) are large DNA viruses with highly infectious characteristics. HHVs can induce lytic and latent infections in their host, and most of these viruses are neurotropic, with the capacity to generate severe and chronic neurological diseases of the peripheral nervous system (PNS) and central nervous system (CNS). Treatment of HHV infections based on strategies that include natural products-derived drugs is one of the most rapidly developing fields of modern medicine. Therefore, in this paper, we lend insights into the recent advances that have been achieved during the past five years in utilizing flavonoids as promising natural drugs for the treatment of HHVs infections of the nervous system such as alpha-herpesviruses (herpes simplex virus type 1, type 2, and varicella-zoster virus), beta-herpesviruses (human cytomegalovirus), and gamma-herpesviruses (Epstein–Barr virus and Kaposi sarcoma-associated herpesvirus). The neurological complications associated with infections induced by the reviewed herpesviruses are emphasized. Additionally, this work covers all possible mechanisms and pathways by which flavonoids induce promising therapeutic actions against the above-mentioned herpesviruses.

(±)-Catechin—A Mass-Spectrometry-Based Exploration Coordination Complex Formation with FeII and FeIII

Catechin is an extensively investigated plant flavan-3-ol with a beneficial impact on human health that is often associated with antioxidant activities and iron coordination complex formation. The aim of this study was to explore these properties with FeII and FeIII using a combination of nanoelectrospray-mass spectrometry, differential pulse voltammetry, site-specific deoxyribose degradation assay, FeII autoxidation assay, and brine shrimp mortality assay. Catechin primarily favored coordination complex formation with Fe ions of the stoichiometry catechin:Fe in the ratio of 1:1 or 2:1. In the detected Fe–catechin coordination complexes, FeII prevailed. Differential pulse voltammetry, the site-specific deoxyribose degradation, and FeII autoxidation assays proved that coordination complex formation affected catechin’s antioxidant effects. In situ formed Fe–catechin coordination complexes showed no toxic activities in the brine shrimp mortality assay. In summary, catechin has properties for the possible treatment of pathological processes associated with ageing and degeneration, such as Alzheimer’s and Parkinson’s diseases.

Anti-Inflammatory and Active Biological Properties of the Plant-Derived Bioactive Compounds Luteolin and Luteolin 7-Glucoside

Flavonoids are interesting molecules synthetized by plants. They can be found abundantly in seeds and fruits, determining the color, flavor, and other organoleptic characteristics, as well as contributing to important nutritional aspects. Beyond these characteristics, due to their biochemical properties and characteristics, they can be considered bioactive compounds. Several interesting studies have demonstrated their biological activity in different cellular and physiological processes in high-order organisms including humans. The flavonoid molecular structure confers the capability of reacting with and neutralizing reactive oxygen species (ROS), behaving as scavengers in all processes generating this class of molecules, such as UV irradiation, a process widely present in plant physiology. Importantly, the recent scientific literature has demonstrated that flavonoids, in human physiology, are active compounds acting not only as scavengers but also with the important role of counteracting the inflammation process. Among the wide variety of flavonoid molecules, significant results have been shown by investigating the role of the flavones luteolin and luteolin-7-O-glucoside (LUT-7G). For these compounds, experimental results demonstrated an interesting anti-inflammatory action, both in vitro and in vivo, in the interaction with JAK/STAT3, NF-κB, and other pathways described in this review. We also describe the effects in metabolic pathways connected with inflammation, such as cellular glycolysis, diabetes, lipid peroxidation, and effects in cancer cells. Moreover, the inhibition of inflammatory pathway in endothelial tissue, as well as the NLRP3 inflammasome assembly, demonstrates a key role in the progression of such phenomena. Since these micronutrient molecules can be obtained from food, their biochemical properties open new perspectives with respect to the long-term health status of healthy individuals, as well as their use as a coadjutant treatment in specific diseases.

Phytochemical and Nutritional Profile Composition in Fruits of Different Sweet Chestnut (Castanea sativa Mill.) Cultivars Grown in Romania

Chestnut (Castanea sativa Mill.), a valuable fruit crop, is cultivated in small areas in Romania, mostly in the west, where the moderate continental climate has a slight Mediterranean influence. This work aims to investigate the bioactive characteristics (total polyphenols, total flavonoids and antioxidant activity), individual polyphenolic composition, phytochemical and nutritional HRMS screening profiles, sugar and mineral composition of six sweet chestnut cultivars, namely ‘Marsol’, ‘Maraval’, ‘Bournette’, ‘Précoce Migoule’ and ‘Marissard’ grown at Fruit Growing Research—Extension Station (SCDP) Vâlcea, in Northern Oltenia, Romania. Fruit samples were collected in two consecutive years, in order to study the impact of genetic variability between cultivars and the influence of the different climatic conditions corresponding to different cultivation years. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) allow the discrimination between the sweet chestnut fruits harvested in different years and different sweet chestnut cultivars. Analytical investigations revealed that sweet chestnut cultivars grown in Romania show similar bioactive, phytochemical and nutritional composition to cultivars grown in the large European chestnut-producing countries, indicating the high adaptation potential of the chestnut in the temperate continental zone with small Mediterranean influences characteristic of the southwestern area of Romania.