Gallic Acid Research Articles

The Anti-psoriatic Effect of Gallic Acid is Associated with the Suppression of Keratin 6 and Nrf2

Background: Psoriasis is recognized as an autoimmune dermatosis, and keratin 6 (KRT 6) is a hallmark of psoriasis. Gallic acid (GA) is a natural and small molecule with a series of biological activities. However, the effect of GA on psoriasis has not been clarified. Aims: This study aimed to investigate the anti-psoriatic activity of GA in psoriasis-like mice and in vitro. Methods: The transcriptions of the Homo sapiens KRT6 gene, and Mus musculus KRT6 gene, were identified using a quantitative real-time reverse transcriptase PCR (qRT-PCR) assay. Expressions of KRT 6, STAT3, pSTAT3, Nrf2, and pNrf2 in HaCaT cells and skin biopsies were determined with a western blotting assay. The immunofluorescence (IF) assay was used to examine the expression of KRT6, pSTAT3, and pNrf2 in HaCaT cells. The expression of KRT 6, PCNA, Ki67, and CD3 was evaluated on the skin of psoriasis-like mice and quantified with histochemical scores (H scores). Results: GA significantly inhibited KRT 6 gene transcription and expression in psoriasis-like disease both in vitro and in vivo. It significantly inhibited the expression of keratinocyte proliferation markers (PCNA and Ki67), suppressed the expression of CD3 (a marker of T cells), and decreased the thickness of the folded skin, as well as improved the splenomegaly in imiquimod-induced mice similar to psoriasis. Furthermore, the suppressing effect of GA on KRT 6 was abolished by the continuous activation of Nrf2 rather than STAT3, although GA significantly inhibited Nrf2 and STAT3 activation in IL-17A-induced HaCaT cells. Conclusions: KRT 6 acts as a potential target for GA against psoriasis, and the anti-psoriatic effect of GA could be related to Nrf2 signaling.

Protective Roles and Therapeutic Effects of Gallic Acid in the Treatment of Cardiovascular Diseases: Current Trends and Future Directions.

Cardiovascular diseases (CVDs) are serious life-threatening illnesses and significant problematic issues for public health having a heavy economic burden on all society worldwide. The high incidence of these diseases as well as high mortality rates make them the leading causes of death and disability. Therefore, finding novel and more effective therapeutic methods is urgently required. Gallic acid, an herbal medicine with numerous biological properties, has been utilized in the treatment of various diseases for thousands of years. It has been demonstrated that gallic acid possesses pharmacological potential in regulating several molecular and cellular processes such as apoptosis and autophagy. Moreover, gallic acid has been investigated in the treatment of CVDs both in vivo and in vitro. Herein, we aimed to review the available evidence on the therapeutic application of gallic acid for CVDs including myocardial ischemia-reperfusion injury and infarction, drug-induced cardiotoxicity, hypertension, cardiac fibrosis, and heart failure, with a focus on underlying mechanisms.

Effects of Polyphenols and Lignans of Phyllanthus amarus Schumach. and Thonn. on IL-1β and TNF-α Secretions from LPS-induced THP-1-derived Macrophages

Background: Phyllanthus amarus exhibited immunosuppressive and anti-inflammatory effects in several in vitro and in vivo studies. However, there is no report on the inhibitory effects of its secondary metabolites on pro-inflammatory cytokines secretion from human THP-1-derived macrophages. background: Phyllanthus amarus exhibited immunosuppressive and anti-inflammatory effects in several in vitro and in vivo studies. However, there is no report on the inhibitory effects of its secondary metabolites on pro-inflammatory cytokines secretion from human THP-1-derived macrophages. Objective: The objective of this study was to correlate the polyphenols (ellagic acid (EA), gallic acid (GA), geraniin (GER), and corilagin (COR)) and lignans ((phyllanthin (PHY), hypophyllanthin (HYPO), niranthin (NIR), phyltetralin (PHYLT), and isolintetralin (ISO)) of 80% ethanol extract of P. amarus with their inhibitory effect against IL-1β and TNF-α secretions from LPS-induced THP-1- derived macrophages. Methods: Chemical profiling of P. amarus was carried out by LC-MS/MS analysis. Validated qualitative and quantitative reversed-phase HPLC analyses of the P. amarus extract were performed for the determination of lignan and polyphenol contents. Human THP-1-derived macrophages were prepared by treatment of THP-1 cells with phorbol 12-myristate 13-acetate (PMA). The inhibition of cytokines released by the extract, lignans and polyphenols in the cells was investigated using ELISA assay. method: Chemical profiling of P. amarus was carried out by LC-MS/MS analysis. Validated qualitative and quantitative reversed phase HPLC analyses of the P. amarus extract were performed for determination of lignan and polyphenol contents. Human THP-1 derived macrophages were prepared by treatment of THP-1 cells with phorbol 12-myristate 13-acetate (PMA). The inhibition of cytokines release by the extract, lignans and polyphenols in the cells were investigated using ELISA assay. Results: P. amarus extract and its chemical constituents significantly reduced the levels of IL-1β and TNF-α in a dose-dependent manner. At a dose of 50 μM, COR exhibited a maximum inhibition of 81.11% on TNF-α secretion, while GER showed 72.56% inhibition on IL-1β secretion. COR demonstrated the strongest inhibition of TNF-α secretion, exhibiting an IC50 value of 9.06 μM, which was comparable to that of dexamethasone (7.07 μM). Meanwhile, GER was the most potent against IL- 1β secretion, exhibiting an IC50 value of 20.09 μM. In the case of TNF-α secretion, the order of potency observed among the active compounds, with regard to IC50 value, was COR > GER > HYPO > PHY > NIR > GA > EA >ISO > PHYLT. For IL-1β secretion, the order of potency was GER > NIR > COR > GA > EA > PHY > HYPO > PHYLT > 1SO. Conclusion: The polyphenol contents of P. amarus, especially COR and GER, contributed significantly to the suppression of cytokines secretion, and they have the potential to be developed into agents for the treatment of pathologic inflammation.

Chemical Composition and Therapeutic Potential of Syngonium podophyllum L. Leaves against Hypercholesterolemia in Rats: Liver, Kidney, and Heart Crosstalk

Background: One of the main risk factors for atherosclerosis is hypercholesterolemia Objective: This study aimed to assess hypercholesterolemia's effect on the liver, heart, and kidney and the impact of Syngonium podophyllum L. leaves methanolic extract as a treating agent in a rat model. Methods: Flavonoid components were isolated and identified from the methanolic extract of Syngonium podophyllum L. leaves. Total serum leptin, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), aspartate and alanine aminotransferases (AST and ALT), urea, and creatinine levels were all measured as part of the biochemical evaluation. The liver tissue was tested for levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), and DNA fragmentation. Results: Thirty-nine compounds were identified by GC/MS profiling of the n-hexane fraction of Syngonium podophyllum L leaves. The major volatile constituents were decane, 4-methyl, decane, N-acetyl 3-pentenyl, 1-amine, 2-methyl, 1-hexene, and 3-hydroxy, propanenitrile, while the major phenolic compounds isolated from methanolic extract were luteolin-7- α-L rhamnoside-4'- O-β-glucopyranoside (1), apigenin 6, 8-di-C-β-glucopyranoside (vicenin 2) (2), quercetin-3-Oα-L-rhamnoside (3), quercetin-7-O-β-glucoside compound (4), luteolin-7-O-β-glucoside (5), 5- hydroxy-6,7,8,4'-tetramethoxy flavone (6), gallic acid (7) and quercetin (8). Hypercholesterolemic rats revealed significant alterations (p ≤ 0.05) in the lipid profile, liver and kidney function, DNA fragmentation pattern and antioxidant indices. With oral cholesterol administration of 30 mg/0.3 mL, 0.7% tween/rats fed a high-fat diet for nine weeks, treatment with leaves extract (250 mg/kg body weight) was able to restore all biochemical parameters as well as the architectures of the liver and heart. Conclusion: Due to its abundance in physiologically active phenolic and flavonoid components, the methanolic extract of Syngonium podophyllum L. leaves successfully served as a hypolipidemic, anti-atherosclerotic, and antioxidant therapeutic agent.

Quantification of Total Phenol Concentration in Ethanol Extracts of Red and Black Betel Leaves Using UV-Vis Spectrophotometric Method

Red betel (Piper crocatum Ruiz & Pav) and black betel leaves (Piper betle var. nigra) are plant varieties known for their medicinal properties. These plants have various contents including flavonoids, essential oils, tannins and polyphenols. The objective of this research is to ascertain the quantity of phenolic compounds present in ethanol extracts of red and black betel leaves. Determination of the levels of ethanol extracts of red and black betel leaves is done quantitatively by the folin-ciocalteu method. This method relies on the formation of a blue complex compound of of phosphomolybdat-phosphotungstat, generated by the reduction of phenolic compounds in an alkaline environment. The measurement is performed using uv-vis spectrophotometry. Gallic acid, derived from hydroxybenzoic acid and identified as a simple phenolic acid, is employed. This stable and pure polyphenolic compound is commonly found in almost all plants. Drawing conclusions from the study results, it can be affirmed that the average total phenol concentration of red betel was 31.87 GAE per gram extract and the average total phenol concentration of black betel leaves was 39.09 mg GAE per gram extract.

Flexible monolayer films of poly(lactic acid)/gallic acid for active food packaging: Preparation, characterization, and bioactive properties

AbstractThe design of eco‐friendly active food packaging systems based on biobased polymeric materials is a growing field of research because of the pressing concern for sustainable development. Herein, monolayer ternary thermoplastic films composed of poly(lactic acid) (PLA), gallic acid (GA, 2.5% w/w relative to PLA), and a plasticizer (poly(ethylene glycol) [PEG] or epoxidized linseed oil [ELO], 5.0 and 7.5% w/w relative to PLA) are prepared via melt‐mixing followed by compression molding. The ensuing plasticized and self‐standing PLA/GA films are translucent and have good mechanical properties (Young's modulus ~2 GPa) and welding performance. The incorporation of GA yields films with ultraviolet‐light barrier properties (transmittance below 40%, 200–400 nm), antioxidant capacity (radical scavenging activity above 94%), and antibacterial activity against the methicillin‐resistant strain of Staphylococcus aureus (minimum of 3‐log reduction colony forming units mL−1). These thermoplastic films are easily degradable via enzymatic degradation with proteinase K from Tritirachium album, reaching weight loss values of 100% after 9 days. The films plasticized with PEG present slightly better antibacterial action and enzymatic degradation, whereas those plasticized with ELO exhibit marginally higher surface hydrophobicity and thermal stability. Thus, the combination between PLA and GA yielded biobased films with bioactive properties that have potential for application in active food packaging.

Gallic acid pretreatment mitigates parathyroid ischemia–reperfusion injury through signaling pathway modulation

Thyroid surgery often results in ischemia–reperfusion injury (IRI) to the parathyroid glands, yet the mechanisms underlying this and how to ameliorate IRI remain incompletely explored. Our study identifies a polyphenolic herbal extract—gallic acid (GA)—with antioxidative properties against IRI. Through flow cytometry and CCK8 assays, we investigate the protective effects of GA pretreatment on a parathyroid IRI model and decode its potential mechanisms via RNA-seq and bioinformatics analysis. Results reveal increased apoptosis, pronounced G1 phase arrest, and significantly reduced cell proliferation in the hypoxia/reoxygenation group compared to the hypoxia group, which GA pretreatment mitigates. RNA-seq and bioinformatics analysis indicate GA’s modulation of various signaling pathways, including IL-17, AMPK, MAPK, transient receptor potential channels, cAMP, and Rap1. In summary, GA pretreatment demonstrates potential in protecting parathyroid cells from IRI by influencing various genes and signaling pathways. These findings offer a promising therapeutic strategy for hypoparathyroidism treatment.

Combined effect of gallic acid and zinc ferrite nanoparticles on wheat growth and yield under salinity stress

Salinity stress significantly impacts crops, disrupting their water balance and nutrient uptake, reducing growth, yield, and overall plant health. High salinity in soil can adversely affect plants by disrupting their water balance. Excessive salt levels can lead to dehydration, hinder nutrient absorption, and damage plant cells, ultimately impairing growth and reducing crop yields. Gallic acid (GA) and zinc ferrite (ZnFNP) can effectively overcome this problem. GA can promote root growth, boost photosynthesis, and help plants absorb nutrients efficiently. However, their combined application as an amendment against drought still needs scientific justification. Zinc ferrite nanoparticles possess many beneficial properties for soil remediation and medical applications. That’s why the current study used a combination of GA and ZnFNP as amendments to wheat. There were 4 treatments, i.e., 0, 10 µM GA, 15 μM GA, and 20 µM GA, without and with 5 μM ZnFNP applied in 4 replications following a completely randomized design. Results exhibited that 20 µM GA + 5 μM ZnFNP caused significant improvement in wheat shoot length (28.62%), shoot fresh weight (16.52%), shoot dry weight (11.38%), root length (3.64%), root fresh weight (14.72%), and root dry weight (9.71%) in contrast to the control. Significant enrichment in wheat chlorophyll a (19.76%), chlorophyll b (25.16%), total chlorophyll (21.35%), photosynthetic rate (12.72%), transpiration rate (10.09%), and stomatal conductance (15.25%) over the control validate the potential of 20 µM GA + 5 μM ZnFNP. Furthermore, improvement in N, P, and K concentration in grain and shoot verified the effective functioning of 20 µM GA + 5 μM ZnFNP compared to control. In conclusion, 20 µM GA + 5 μM ZnFNP can potentially improve the growth, chlorophyll contents and gas exchange attributes of wheat cultivated in salinity stress. More investigations are suggested to declare 20 µM GA + 5 μM ZnFNP as the best amendment for alleviating salinity stress in different cereal crops.

Benefits of Taurisolo in Diabetic Patients with Peripheral Artery Disease.

Trimethyl-N-oxide (TMAO) has been linked to peripheral artery disease (PAD). TaurisoloⓇ is a natural, balanced phytocomplex containing resveratrol, quercetin, catechins, procianidins, gallic acid, and caffeic acid. Numerous studies have shown that TaurisoloⓇ reduces the damage of TMAO and exerts a protective effect on endothelial cells (ECs). The aim of this randomized, double-blind, single-center study was to evaluate the effects of TaurisoloⓇ on claudication in patients with PAD (Rutheford grade I, category II, Fontaine Classification: Stage IIA, American Medical Association Whole Person Impairment Classification: Class 0-WPI 0%) in two parallel groups of 31 patients. The primary outcomes were an increase in the pain-free walking distance and the ankle/brachial pressure index at the beginning and at the end of the treatment with Taurisolo. The secondary endpoint was the serum TMAO changes. The claudication distance improved by 14.1% in the Taurisolo group and by 2.0% in the placebo group, while the maximal distance increased by 15.8% and 0.6% only, respectively (both p < 0.05). The TMAO plasma levels decreased from 3.97 ± 2.13 micromole/L to 0.87 ± 0.48 (p < 0.0001) in the treated group. All these changes were highly significant both in univariate mixed models as well as in the adjusted model. Ultimately, TaurisoloⓇ might be an effective intervention to ameliorate intermittent claudication.

Niosome-Based Hydrogel of Quince Extract: A Promising Strategy for Expedited Full-thickness Wound Healing in Rat.

The regeneration of tissue damage involves a series of molecular and cellular events that can be mediated by various natural compounds. Recent studies have highlighted the anti-inflammatory, anti-ulcer, and skin-protecting properties of Cydonia oblonga (Quince), which are mainly attributed to phenolic compounds. These compounds may have some drawbacks when targeting wound applications, including low bioavailability at the wound site. Moreover, to overcome these limitations, surfactant-based nanovesicular systems have been developed as carriers of such compounds for wound healing. This study aimed to highlight the possible therapeutic potential of niosome-based hydrogel from Quince extract to stabilize and deliver the related bioactive compounds to full-thickness wounds in rats. The niosomal hydrogel was prepared using a thin-film hydration method with the fruit extract (70% methanol). The formulation was optimized by evaluating size, zeta potential, dispersion index, and drug encapsulation efficiency. Full-thickness wounds were created on the dorsal cervical area of Wistar rats, and histopathological analysis of biopsy specimens was conducted on the 12th day of treatment. Under the study conditions, niosomal hydrogel displayed good physicochemical stability. Histopathological findings demonstrated that niosomal gel promoted angiogenesis, fibroblast maturation, collagen deposition, keratinization, and epidermal layer formation more effectively than control and hydrogel base. Furthermore, niosomal gel treatment markedly reduced inflammation. The total phenol concentration was determined to be 13.34 ± 0.90 mg gallic acid equivalents per gram of dried extract. The niosomal hydrogel containing C. oblonga extract shows potential as a novel approach for wound healing, warranting further investigation in this field.

Antioxidant and antimicrobial characteristics of mangosteen peel extract and synergistic capacity in beef burger preservation

SummaryThis study aimed to investigate the efficiency of mangosteen peel extract (MPE) in preservation of beef burgers. MPE was first evaluated for its total phenolic content (TPC), total flavonoid content (TFC) and antioxidant and antimicrobial activities. Subsequently, beef burgers were prepared with different MPE amounts (0–1%) and stored for 1 day, 3 days and 5 days. The synthetic antioxidant 2,6‐di‐tert‐butyl‐4‐methyl phenol (BHT) and synthetic antimicrobial sodium benzoate (SB) were used for comparison. The changes of burgers in physicochemical parameters (moisture, cooking loss, storage loss and pH), lipid and protein oxidation (peroxide value, PV; thiobarbituric acid reactive substances, TBARS and carbonyl content), microbiological (total viable count, TVC) and sensory characteristics were assessed. The results revealed that MPE contained a high TPC of 128.93 mg gallic acid equivalent g−1 dry extract and TFC of 62.98 mg rutin equivalent g−1 dry extract. These bioactive compounds rendered MPE with its antioxidant activity approximately equivalent to ascorbic acid and antimicrobial activities against Escherichia coli and Staphylococcus aureus comparable with SB. MPE‐combined burger samples had higher moisture and cooking loss (P &lt; 0.05) but almost equal storage loss and pH value compared with the control samples (P &gt; 0.05). However, the incorporation of MPE into beef burgers did not affect the sensory attributes and preferences of consumers (P &gt; 0.05). The burger with 1% MPE had lower values of PV, TBARS and carbonyl content than all other samples (P &lt; 0.05), including the one added with BHT, indicating the strong potential of MPE as natural antioxidant alternative to prevent the oxidation of lipids and proteins. Through the TVC test, 1% MPE was demonstrated to result in the safe preservation of burgers up to 5 days of storage, equivalent to SB (P &gt; 0.05). Therefore, MPE could become a natural synergistic alternative to both synthetic antioxidant and antimicrobial in the preservation of meat and meat products.

Synergistic antioxidant and antibacterial activities of polyphenol extracts from mangosteen peels in preservation of Pangasius hypophthalmus fish balls

In recent years, natural preservatives have attracted more and more attention in food processing since they can enhance food shelf-life and safety. In this study, the polyphenol extract was obtained from mangosteen peels using enzyme-microwave assisted method, characterized for its antioxidant and antimicrobial activities and subsequently used as a natural additive in fish ball preservation. Results revealed that the mangosteen peel polyphenol powder (MPP) had a high phenolic content of 154 mg gallic acid equivalent/g dry matter, which led to high 2,2-diphenyl-1-picrylhydrazyl free radical scavenging capacity of 95 mg Trolox equivalent/g dry matter. MPP also exhibited effective antimicrobial activity against E. coli and S. aureus, expressed by its large inhibitory zones (11.3 and 12.1 mm, respectively) and small ratios (less than 4) of minimum bactericidal concentration over minimum inhibitory concentration against tested bacteria. The MPP supplementation at the levels of 38 mg/100 g and 53 mg/100 g into fish balls remarkably improved their gel strength, reduced lipid oxidation, limited protein oxidation and structural degradation as compared to those of the control without any addition or with synthetic preservatives. Especially, the addition of 53 mg MPP/100 g could sufficiently retard the microorganism growth. The synergistic effects of MPP in both antioxidant and antimicrobial activities hence could extend the shelf-life of fish balls, more than 40 %, as compared to butylated hydroxytoluene (synthetic antioxidant) or sodium benzoate (synthetic antimicrobial) with their single effects. These findings imply that MPP could be potentially used as a natural additive in preservation of fish and meat products.

Inhibition of SARS-CoV-2-Induced NLRP3 Inflammasome-Mediated Lung Cell Inflammation by Triphala-Loaded Nanoparticle Targeting Spike Glycoprotein S1.

The COVID-19 pandemic, caused by SARS-CoV-2, poses a significant global health threat. The spike glycoprotein S1 of the SARS-CoV-2 virus is known to induce the production of pro-inflammatory mediators, contributing to hyperinflammation in COVID-19 patients. Triphala, an ancient Ayurvedic remedy composed of dried fruits from three plant species-Emblica officinalis (Family Euphorbiaceae), Terminalia bellerica (Family Combretaceae), and Terminalia chebula (Family Combretaceae)-shows promise in addressing inflammation. However, the limited water solubility of its ethanolic extract impedes its bioavailability. In this study, we aimed to develop nanoparticles loaded with Triphala extract, termed "nanotriphala", as a drug delivery system. Additionally, we investigated the in vitro anti-inflammatory properties of nanotriphala and its major compounds, namely gallic acid, chebulagic acid, and chebulinic acid, in lung epithelial cells (A549) induced by CoV2-SP. The nanotriphala formulation was prepared using the solvent displacement method. The encapsulation efficiency of Triphala in nanotriphala was determined to be 87.96 ± 2.60% based on total phenolic content. In terms of in vitro release, nanotriphala exhibited a biphasic release profile with zero-order kinetics over 0-8 h. A549 cells were treated with nanotriphala or its active compounds and then induced with 100 ng/mL of spike S1 subunit (CoV2-SP). The results demonstrate that chebulagic acid and chebulinic acid are the active compounds in nanotriphala, which significantly reduced cytokine release (IL-6, IL-1β, and IL-18) and suppressed the expression of inflammatory genes (IL-6, IL-1β, IL-18, and NLRP3) (p < 0.05). Mechanistically, nanotriphala and its active compounds notably attenuated the expression of inflammasome machinery proteins (NLRP3, ASC, and Caspase-1) (p < 0.05). In conclusion, the nanoparticle formulation of Triphala enhances its stability and exhibits anti-inflammatory properties against CoV2-SP-induction. This was achieved by suppressing inflammatory mediators and the NLRP3 inflammasome machinery. Thus, nanotriphala holds promise as a supportive preventive anti-inflammatory therapy for COVID-19-related chronic inflammation.

Comparative study on the effects of grain blending on functional compound content and in vitro biological activity

In this study, changes in bioactive compound contents and the in vitro biological activity of mixed grains, including oats, sorghum, finger millet, adzuki bean, and proso millet, with eight different blending ratios were investigated. The total phenolic compounds and flavonoid contents ranged from 14.43–16.53 mg gallic acid equivalent/g extract and 1.22–5.37 mg catechin equivalent/g extract, respectively, depending on the blending ratio. The DI-8 blend (30% oats, 30% sorghum, 15% finger millet, 15% adzuki bean, and 10% proso millet) exhibited relatively higher antioxidant and anti-diabetic effects than other blending samples. The levels of twelve amino acids and eight organic acids in the grain mixes were measured. Among the twenty metabolites, malonic acid, asparagine, oxalic acid, tartaric acid, and proline were identified as key metabolites across the blending samples. Moreover, the levels of lactic acid, oxalic acid, and malonic acid, which are positively correlated with α-glucosidase inhibition activity, were considerably higher in the DI-blending samples. The results of this study suggest that the DI-8 blend could be used as a functional ingredient as it has several bioactive compounds and biological activities, including anti-diabetic activity.

Structure-activity relationship studies of pyrogallol as a calcineurin/NFAT signaling suppressor

Previously, we have shown that pyrogallol alleviated nasal symptoms and suppressed IL-9 gene up-regulation in allergy model rats by inhibiting calcineurin/NFAT signaling. As pyrogallol has antioxidative activity, it may be responsible for inhibiting calcineurin/NFAT signaling-mediated IL-9 gene expression. However, the relationship between antioxidative activity and suppression of IL-9 gene expression has not been elucidated yet. Here, we conducted the structure-activity relationship studies of pyrogallol and its structurally related compounds to understand the mechanism of IL-9 gene suppression by pyrogallol. 2, 2-Diphenyl-1-picrylhydrazyl radical scavenging assay showed that the antioxidative activity of catechol, resorcinol, phloroglucinol, and gallic acid is 60.1%, 10.4%, 18.8%, and 113.5% of pyrogallol, respectively. Catechol, resorcinol, and phloroglucinol did not suppress NFAT dephosphorylation. Gallic acid suppressed dephosphorylation of NFAT. Gallic acid also suppressed ionomycin-induced up-regulation of IL-9 gene expression with the IC50 value of 82.6 μM. However, catechol, resorcinol and phloroglucinol showed no suppressive activity. In addition, using gallic acid-immobilized beads, we isolated and identified Poly(U)-binding-splicing factor 60 (PUF60) as a pyrogallol binding protein. These results suggest that the antioxidative activity of pyrogallol is not likely to be the mechanism of IL-9 gene suppression. Data also suggest that PUF60 is one of its target molecules responsible for the suppression of calcineurin/NFAT signaling by pyrogallol.

Polyvinyl alcohol-based multifunctional hydrogel film: a novel strategy for food preservation packaging

Food spoilage leads to the annual huge wastage of food. There is a pressing need for safe, multifunctional food preservation packaging to curb this wastage and prevent contamination. In this study, we present a novel, cross-linked P-GL hydrogel film with a smooth surface microstructure, derived from polyvinyl alcohol (PVA), gallic acid (GA), and lysozyme (L). This hydrogel film serves as an exceptional packaging material for food preservation, displaying an ability to completely block UV light and efficiently impede the penetration of water vapor and O2. Remarkably, the P-GL hydrogel film exhibits a fracture strength of approximately 37.9 MPa, demonstrating superior water solubility, thermal stability, and mechanical properties. Also, this P-GL hydrogel film can effectively eliminate E. coli and S. aureus. The P-GL hydrogel film has proven to be successful in mitigating the spoilage of blueberries through coating and covering treatments, outperforming commercial plastic wrap. As a result, the shelf life of blueberries can be extended to 20 days. Our work provides innovative insights that could potentially drive the use of safe and multifunctional hydrogel films in the food preservation packaging industry.

A Review of Antidiabetic Medicinal Plants as a Novel Source of Phosphodiesterase Inhibitors: Future Perspective of New Challenges Against Diabetes Mellitus.

Intracellular glucose concentration plays a crucial role in initiating the molecular secretory process of pancreatic β-cells through multiple messengers and signaling pathways. Cyclic nucleotides are key physiological regulators that modulate pathway interactions in β-cells. An increase of cyclic nucleotides is controled by hydrolysed phosphodiesterases (PDEs), which degrades cyclic nucleotides into inactive metabolites. Despite the undeniable therapeutic potential of PDE inhibitors, they are associated with several side effects. The treatment strategy for diabetes based on PDE inhibitors has been proposed for a long time. Hence, the world of natural antidiabetic medicinal plants represents an ideal source of phosphodiesterase inhibitors as a new strategy for developing novel agents to treat diabetes mellitus. This review highlights medicinal plants traditionally used in the treatment of diabetes mellitus that have been proven to have inhibitory effects on PDE activity. The contents of this review were sourced from electronic databases, including Science Direct, PubMed, Springer Link, Web of Science, Scopus, Wiley Online, Scifinder and Google Scholar. These databases were consulted to collect information without any limitation date. After comprehensive literature screening, this paper identified 27 medicinal plants that have been reported to exhibit anti-phosphodiesterase activities. The selection of these plants was based on their traditional uses in the treatment of diabetes mellitus. The review emphasizes the antiphosphodiesterase properties of 31 bioactive components derived from these plant extracts. Many phenolic compounds have been identified as PDE inhibitors: Brazilin, mesozygin, artonin I, chalcomaracin, norartocarpetin, moracin L, moracin M, moracin C, curcumin, gallic acid, caffeic acid, rutin, quercitrin, quercetin, catechin, kaempferol, chlorogenic acid, and ellagic acid. Moreover, smome lignans have reported as PDE inhibitors: (+)-Medioresinol di-O-β-d-glucopyranoside, (+)- Pinoresinol di-O-β-d-glucopyranoside, (+)-Pinoresinol-4-O-β-d-glucopyranosyl (1→6)-β-dglucopyranoside, Liriodendrin, (+)-Pinoresinol 4'-O-β-d-glucopyranoside, and forsythin. This review provides a promising starting point of medicinal plants, which could be further studied for the development of natural phosphodiesterase inhibitors to treat diabetes mellitus. Therefore, it is important to consider clinical studies for the identification of new targets for the treatment of diabetes.

Engineering cascade biocatalysis in whole cells for syringic acid bioproduction

BackgroundSyringic acid (SA) is a high-value natural compound with diverse biological activities and wide applications, commonly found in fruits, vegetables, and herbs. SA is primarily produced through chemical synthesis, nonetheless, these chemical methods have many drawbacks, such as considerable equipment requirements, harsh reaction conditions, expensive catalysts, and numerous by-products. Therefore, in this study, a novel biotransformation route for SA production was designed and developed by using engineered whole cells.ResultsAn O-methyltransferase from Desulfuromonas acetoxidans (DesAOMT), which preferentially catalyzes a methyl transfer reaction on the meta-hydroxyl group of catechol analogues, was identified. The whole cells expressing DesAOMT can transform gallic acid (GA) into SA when S-adenosyl methionine (SAM) is used as a methyl donor. We constructed a multi-enzyme cascade reaction in Escherichia coli, containing an endogenous shikimate kinase (AroL) and a chorismate lyase (UbiC), along with a p-hydroxybenzoate hydroxylase mutant (PobA**) from Pseudomonas fluorescens, and DesAOMT; SA was biosynthesized from shikimic acid (SHA) by using whole cells catalysis. The metabolic system of chassis cells also affected the efficiency of SA biosynthesis, blocking the chorismate metabolism pathway improved SA production. When the supply of the cofactor NADPH was optimized, the titer of SA reached 133 μM (26.2 mg/L).ConclusionOverall, we designed a multi-enzyme cascade in E. coli for SA biosynthesis by using resting or growing whole cells. This work identified an O-methyltransferase (DesAOMT), which can catalyze the methylation of GA to produce SA. The multi-enzyme cascade containing four enzymes expressed in an engineered E. coli for synthesizing of SA from SHA. The metabolic system of the strain and biotransformation conditions influenced catalytic efficiency. This study provides a new green route for SA biosynthesis.Graphical

Gallic acid attenuates murine ulcerative colitis by promoting group 3 innate lymphocytes, affecting gut microbiota, and bile acid metabolism

Gallic acid attenuates murine ulcerative colitis by promoting group 3 innate lymphocytes, affecting gut microbiota, and bile acid metabolism

Surface pretreatment of scheelite and cassiterite by gallic acid to achieve high efficiency flotation separation

Scheelite and cassiterite are common tungsten and tin oxide minerals that often coexist in nature. However, the similar oxidation degrees and solution and surface chemical properties of scheelite and cassiterite pose challenges to their flotation separation. Moreover, research in this area is currently limited. This study investigated the selective depression mechanism of gallic acid (GA) in the flotation separation of scheelite and cassiterite and successfully achieved the effective separation of the two minerals. Single mineral and artificially mixed mineral experiments were performed to analyze the flotation separation behavior of scheelite and cassiterite. The results revealed that in the absence of a depressant, scheelite and cassiterite exhibited recovery of 93.43 % and 89.72 %, respectively. After the addition of 5 × 10−4 mol/L GA to the mineral slurry, the grades of WO3 and Sn in the flotation concentrates were 48.93 % and 18.13 %, with recovery of 82.50 % and 31.62 %, respectively. Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, zeta potential, adsorption amount, contact angle, and atomic force microscopy imaging analyses were conducted to examine the selective depression mechanism of GA in the flotation separation of scheelite and cassiterite. In the slurry, the cassiterite surface provided active Sn sites for the chemical adsorption of GA. Moreover, the phenolate O- donor atoms of the deprotonated polar groups of GA will undergo coordination with metal ions and then adsorb on the mineral surface. GA forms metal gallate through adsorption of its –COOH and –OH groups on mineral surface and produces textured oxide layer rich in OH groups, thus reducing the surface hydrophobicity of cassiterite and then depressing cassiterite. The selective adsorption of GA on the cassiterite surface hindered the further adsorption of NaOL, thereby reducing its surface hydrophobicity. Therefore, GA finally realized the flotation separation of the two minerals.