Bioactive compounds and antioxidant activities of Quercus salicina Blume extract

Protective effects of the secondary metabolites from Quercus salicina Blume against gentamicin-induced nephrotoxicity in zebrafish (Danio rerio) model

To reveal the protective effect on the nephrotoxicity of Quercus salicina Blume(QS), a traditional medicine for the treatment of urolithiasis, the 50 % ethanol extract from the branches and leaves of QS was chemically studied by systematic solvent extraction and HPLC chromatography. Two phenolic acids and three flavonoids were identified by nuclear magnetic resonance spectroscopy, namely Ferulic acid (1), p-Hydroxycinnamic acid (2), Hesperidin (3), Formononetin (4), and Quercetin (5). At the same time, the gentamicin-induced nephrotoxicity of zebrafish was used as a model for the first time. The antioxidant activity of these derivatives with good antioxidant activity screened from free radical scavenging experiments in vitro (DPPH and ABTS) was evaluated in vivo, including protein levels (LPO, NO, GSH, and SOD), kidney injury factor (KIM-1), zebrafish kidney pathology and real-time PCR. The results showed that metabolites 1, 3, and 5 had strong antioxidant activity, and oxidative stress in renal tissue was significantly reduced; KIM-1, TNF-α, and IL-6 mRNA expression in a dose-dependent manner, which preliminarily revealed the protective effect of the secondary metabolites of QS on nephrotoxicity, and preliminarily discussed the structure-activity relationship. This study provides an experimental basis for further exploring the mechanism of QS in the kidney.

Comparison of Antibacterial Activities of Korean Pine (Pinus densiflora) Needle Steam Distillation Extract on Escherichia coli and Staphylococcus aureus Focusing on Membrane Fluidity and Genes Involved in Membrane Lipids and Stress

The antibacterial activity and mechanism of Pinus densiflora extracts against Escherichia coli and Staphylococcus aureus were investigated. The growth inhibition tests of paper diffusion and optical density exhibited that the extracts have potent antibacterial potentials against foodborne pathogens. The measurement of membrane fluidity by fluorescence polarization has indicated that one of the antibacterial mechanisms involves the disruption of membrane integrity resulting in an increase in the membrane fluidity in both of E. coli and S. aureus. The alteration of fatty acid composition was accompanied by the disturbance of membranes thus shifting the proportion of saturated verses unsaturated fatty acids or trans fatty acids from 1.27:1 to 1.35:1 in E. coli and 1.47:1 to 2.31:1 in S. aureus, most likely to compensate for the increased membrane fluidity by means of a higher proportion of saturated fatty acids which is known to render rigidity in membranes. Realtime q-PCR (polymerase chain reaction) analysis of fatty acid synthetic genes and bacterial stress genes revealed that there was minimal influence of P. densiflora extracts on fatty acid genes except for fab I and the stress rpos in E. coli, and relatively greater impact on fatty acid genes and the stress sigB in S. aureus.

Antioxidants in Oak (Quercus sp.): Potential Application to Reduce Oxidative Rancidity in Foods

This review explores the antioxidant properties of oak (Quercus sp.) extracts and their potential application in preventing oxidative rancidity in food products. Oxidative rancidity negatively impacts food quality, causing changes in color, odor, and flavor and reducing the shelf life of products. The use of natural antioxidants from plant sources, such as oak extracts, has gained increasing interest due to potential health concerns associated with synthetic antioxidants. Oak extracts contain various antioxidant compounds, including phenolic acids, flavonoids, and tannins, which contribute to their antioxidative capacity. This review discusses the chemical composition of oak extracts, their antioxidative activity in different food systems, and the safety and potential challenges related to their application in food preservation. The potential benefits and limitations of using oak extracts as an alternative to synthetic antioxidants are highlighted, and future research directions to optimize their application and determine their safety for human consumption are suggested.

UHPLC-MS profiles and antidiarrheal activity of Quercus coccinea münchh. and Quercus robur L. employing in vivo technique

Introduction: Quercus L. genus (Oak) belongs to the family Fagaceae and their galls are used commercially in leather tanning, dyeing, and ink preparation. Several Quercus species were traditionally used to manage wound healing, acute diarrhea, hemorrhoid, and inflammatory diseases. The present study aims to investigate the phenolic content of the 80% aqueous methanol extract (AME) of Q. coccinea and Q. robur leaves as well as to assess their anti-diarrheal activity. Methods: Polyphenolic content of Q. coccinea and Q. robur AME were investigated using UHPLC/MS. The antidiarrheal potential of the obtained extracts was evaluated by conducting a castor oil-induced diarrhea in-vivo model. Result and Discussion: Twenty-five and twenty-six polyphenolic compounds were tentatively identified in Q. coccinea and Q. robur AME, respectively. The identified compounds are related to quercetin, kaempferol, isorhamnetin, and apigenin glycosides and their aglycones. In addition, hydrolyzable tannins, phenolic acid, phenyl propanoides derivatives, and cucurbitacin F were also identified in both species AME of Q. coccinea (250, 500, and 1000 mg/kg) exhibited a significant prolongation in the onset of diarrhea by 17.7 %, 42.6%, and 79.7% respectively while AME of Q. robur at the same doses significantly prolonged the onset of diarrhea by 38.6%, 77.3%, and 2.4 folds respectively as compared to the control. Moreover, the percentage of diarrheal inhibition of Q. coccinea was 23.8%, 28.57%, and 42,86% respectively, and for Q. robur 33.34%, 47.3%, and 57.14% respectively as compared to the control group. Both extracts significantly decreased the volume of intestinal fluid by 27%, 39.78%, and 50.1% for Q. coccinea respectively; and by 38.71%, 51.19%, and 60% for Q. robur respectively as compared to the control group. In addition, AME of Q. coccinea exhibited a peristaltic index of 53.48, 47.18, and 42.28 with significant inhibition of gastrointestinal transit by 18.98%, 28.53%, and 35.95 % respectively; while AME of Q. robur exhibited a peristaltic index of 47.71, 37, and 26.41 with significant inhibition of gastrointestinal transit by 27.72%, 43.89%, and 59.99% respectively as compared with the control group. Notably, Q. robur showed a better antidiarrheal effect in comparison with Q. coccinea and, the highest effect was observed for Q. robur at 1000 mg/kg as it was nonsignificant from the loperamide standard group in all measured parameters.

Application of Quercus salicina extract in the management of urolithiasis

Since 1969, an herbal medicine extracted from Quercus salicina Blume/Quercus stenophylla Makino (QS) has been clinically used for the management of urolithiasis in Japan. Historically, the decoction of leaves and shoots of QS trees was popularly utilized as a folk prescription to remove urinary calculi. This study was designed to perform a brief review of the updated progress of QS extract for urinary stones based on previous studies. A comprehensive literature search was conducted in multiple electronic databases, including Web of Science, PubMed, and EMBASE, and relevant data on QS extract were extracted. As a result, the major mechanism of QS extract for urolithiasis is observed to be closely related to the anti-oxidative activities according to recent studies, leading to inhibition of the accumulation of renal calcium and prevention of stone formation and recurrence of stones. As for the effect of discharging stones, loosening the upper urinary tract has also been noticed recently. More extensive studies are still necessary to systemically evaluate the individual dosage, drug safety, and targeted stone types.

Quercus salicina Blume: Research progress in chemistry and pharmacodynamics (1959-2021)

The crude extracts of different parts (leaves and shoots) of Quercus salicina  Blume (QS) have shown considerable effect in urolithiasis. QS has been widely used in clinical practice and has attracted great research interest The relevant published literature, however, reveals only partial education of its chemical components and bio-active mechanisms, and only two review papers have summarized the QS research progress. In this review, a comprehensive and systematic review of chemistry and pharmacodynamics of QS was carried out using the international authoritative databases (1959-2021), focusing on phenols and flavonoids, and their effect such as urinary stone dissolution, anti-inflammatory, anti-diabetes, anti-bacterial, antioxidant, and anti-allergy activities as well as toxic effects .The aim of review is to provide the most recent and effective literature support for further basic research and application development.

The modulatory potential of herbal antioxidants against oxidative stress and heavy metal pollution: plants against environmental oxidative stress

Free radicals, principally reactive oxygen species (ROS), contribute to oxidative stress in human beings. Free radicals have different mechanisms of action and affect lipids, proteins, and DNA. Heavy metals including cadmium (Cd), lead (Pb), and arsenic are environmental pollutants that may induce oxidative stress and produce ROS, leading to harmful effects on different body systems such as the liver and brain. On the other side, antioxidants can have protective effects against oxidative stress and decrease their toxicity. Herbal antioxidants have potential antioxidative effects. These antioxidants positively affect neurodegenerative diseases, atherosclerotic diseases, lung fibrosis, kidney injuries, and liver toxicities induced by oxidative agents, including heavy metals. In this manuscript, we explained the mechanisms of oxidative stress, and also discussed heavy metals which contribute to human oxidative stress. We further discussed different herbal antioxidants, their mechanisms of action, and their clinical use for various diseases.

In silico analysis of the antimicrobial activity of phytochemicals: towards a technological breakthrough

BACKGROUND

The complications associated with infections from pathogens increasingly resistant to traditional drugs lead to a constant increase in the mortality rate among those affected. In such cases the fundamental purpose of the microbiology laboratory is to determine the sensitivity profile of pathogens to antimicrobial agents. This is an intense and complex work often not facilitated by the test's characteristics. Despite the evolution of the Antimicrobial Susceptibility Testing (AST) technologies, the technological breakthrough that could guide and facilitate the search for new antimicrobial agents is still missing.

METHODS

In this work, we propose the experimental use of in silico instruments, particularly feedforward Multi-Layer Perceptron (MLP) Artificial Neural Network, and Genetic Programming (GP), to verify, but also to predict, the effectiveness of natural and experimental mixtures of polyphenols against several microbial strains.

RESULTS

We value the results in predicting the antimicrobial sensitivity profile from the mixture data. Trained MLP shows very high correlations coefficients (0,93 and 0,97) and mean absolute errors (110,70 and 56,60) in determining the Minimum Inhibitory Concentration and Minimum Microbicidal Concentration, respectively, while GP not only evidences very high correlation coefficients (0,89 and 0,96) and low mean absolute errors (6,99 and 5,60) in the same tasks, but also gives an explicit representation of the acquired knowledge about the polyphenol mixtures.

CONCLUSIONS

In silico tools can help to predict phytobiotics antimicrobial efficacy, providing an useful strategy to innovate and speed up the extant classic microbiological techniques.