Water-soluble Phenolic Compounds Research Articles

Pharmacological activity, phytochemistry, and organ protection of lithospermic acid.

Lithospermic acid (LA) is a water-soluble phenolic acid compound extracted and separated from the dried root and the rhizome of Salviamiltiorrhiza Bge (Labiatae), possessing multiple biological activities. Firstly, in terms of pharmacological activities, LA has been proven to possess anti-inflammatory, antioxidant, autophagy activation, and antiapoptotic properties. Secondly, the pharmacokinetic characteristics of LA show rapid and extensive distribution in various tissues after intravenous administration, followed by rapid elimination and excretion. Additionally, potential therapeutic effects of LA have been found in various diseases such as thrombosis, Parkinson's disease, hepatitis B, diabetes, and psoriasis, among others. Particularly, LA has shown promising prospects in the treatment of clinical heart diseases and has been included in new drug formulations for the treatment of chronic angina, demonstrating superior efficacy compared to current cardiovascular drugs. In conclusion, this review comprehensively introduces the pharmacological mechanisms, pharmacokinetics, and protective effects in diseases of LA. These information can lay a theoretical foundation for the future development and new clinical applications of LA.

Salvianolic acids and its potential for cardio-protection against myocardial ischemic reperfusion injury in diabetes.

The incidence of diabetes and related mortality rate increase yearly in modern cities. Additionally, elevated glucose levels can result in an increase of reactive oxygen species (ROS), ferroptosis, and the disruption of protective pathways in the heart. These factors collectively heighten the vulnerability of diabetic individuals to myocardial ischemia. Reperfusion therapies have been effectively used in clinical practice. There are limitations to the current clinical methods used to treat myocardial ischemia-reperfusion injury. As a result, reducing post-treatment ischemia/reperfusion injury remains a challenge. Therefore, efforts are underway to provide more efficient therapy. Salvia miltiorrhiza Bunge (Danshen) has been used for centuries in ancient China to treat cardiovascular diseases (CVD) with rare side effects. Salvianolic acid is a water-soluble phenolic compound with potent antioxidant properties and has the greatest hydrophilic property in Danshen. It has recently been discovered that salvianolic acids A (SAA) and B (SAB) are capable of inhibiting apoptosis by targeting the JNK/Akt pathway and the NF-κB pathway, respectively. This review delves into the most recent discoveries regarding the therapeutic and cardioprotective benefits of salvianolic acid for individuals with diabetes. Salvianolic acid shows great potential in myocardial protection in diabetes mellitus. A thorough understanding of the protective mechanism of salvianolic acid could expand its potential uses in developing medicines for treating diabetes mellitus related myocardial ischemia-reperfusion.

Salvianolic acid B ameliorates myocardial fibrosis in diabetic cardiomyopathy by deubiquitinating Smad7

BackgroundSalvianolic acid B (Sal B), a water-soluble phenolic compound derived from Salvia miltiorrhiza Bunge, is commonly used in Traditional Chinese Medicine to treat cardiovascular disease. In our previous study, Sal B protected against myocardial fibrosis induced by diabetic cardiomyopathy (DCM). This study aimed to investigate the ameliorative effects and potential mechanisms of Sal B in mitigating myocardial fibrosis induced by DCM.MethodsVarious methods were used to investigate the effects of Sal B on myocardial fibrosis induced by DCM in vivo and in vitro. These methods included blood glucose measurement, echocardiography, HE staining, Masson’s trichrome staining, Sirius red staining, cell proliferation assessment, determination of hydroxyproline levels, immunohistochemical staining, evaluation of fibrosis-related protein expression (Collagen-I, Collagen-III, TGF-β1, p-Smad3, Smad3, Smad7, and α-smooth muscle actin), analysis of Smad7 gene expression, and analysis of Smad7 ubiquitin modification.ResultsThe animal test results indicated that Sal B significantly improved cardiac function, inhibited collagen deposition and phenotypic transformation, and ameliorated myocardial fibrosis in DCM by upregulating Smad7, thereby inhibiting the TGF-β1 signaling pathway. In addition, cell experiments demonstrated that Sal B significantly inhibited the proliferation, migration, phenotypic transformation, and collagen secretion of cardiac fibroblasts (CFs) induced by high glucose (HG). Sal B significantly decreased the ubiquitination of Smad7 and stabilized the protein expression of Smad7, thereby increasing the protein expression of Smad7 in CFs and inhibiting the TGF-β1 signaling pathway, which may be the potential mechanism by which Sal B mitigates myocardial fibrosis induced by DCM.ConclusionThis study revealed that Sal B can improve myocardial fibrosis in DCM by deubiquitinating Smad7, stabilizing the protein expression of Smad7, and blocking the TGF-β1 signaling pathway.

The content of phenols and activity of polyphenol oxidase in the hametophyte of dominant mosses in forest ecosystems of the Ukrainian Roztochia

Bryophytes are indicators of the state of forest ecosystems. Dominant species of forest mosses are sensitive to the influence of abiotic factors and demonstrate adaptive reactions different from vascular plants, which are decisive for the prediction of changes in the natural environment. We have analyzed the changes in the content of water-soluble phenols and the activity of polyphenol oxidase n the hametophyte of dominant epigean forest mosses depending on changes in the intensity of insolation, the water and temperature regime of soils and air in experimental localities of forest ecosystems of the Ukrainian Roztochia. The highest content of water-soluble phenolic compounds was found in the resistant mosses Polytrichum formosum and Atrichum undulatum on the territory of protected beech forest under conditions of low light intensity and sufficient humidity of local vegetation. The maximum indicators of the content of phenolic compounds were found in A. undulatum (199.5±9.8 μg/g of dry matter mass), and the lowest – in Plagiomnium affine (54.7±2.6 μg/g of dry matter mass) that is sensitive to changes in the ecological conditions of local vegetation in all studied areas. A significant decrease in the content of phenolic compounds in areas of disturbed ecosystems may indicate the active participation of phenols in the adaptation of mosses to the effects of high light intensity, elevated temperatures and moisture deficit. The highest indicators of polyphenol oxidase activity were determined in P. affine (120.4±6.1 relative units/g of dry matter mass*s) and P. formosum (41.8±2.1 relative units/g of dry matter mass*s) from local vegetation under unfavorable conditions on the territory of stationary recreation. A direct correlation between the content of phenolic compounds and the activity of polyphenol oxidase was not established. The higher activity of this enzyme under conditions of high light intensity than in shaded local plants may indicate a relationship between polyphenol oxidase and photosynthesis. An increase in the activity of polyphenol oxidase contributes to the significant formation of quinones, which, accumulating in cell walls, reduce the processes of lipid peroxidation, regulate their permeability and ensure better moisture storage in the moss turfs.

Inhibition of continuous cropping obstacle of celery by chemically modified biochar: An efficient approach to decrease bioavailability of phenolic allelochemicals

The accumulation of allelochemicals released by plants is commonly found in continuous monocropping systems. These chemicals, such as phenolic acids, were shown to be the major sources of autotoxin or pathogen accumulation in soils, leading to a direct or indirect continuous cropping obstacle. In this study, three types of agricultural residuals, i.e., rice husk, tea waste, and wood meal, were chosen as feedstocks. Biochar samples were prepared from these feedstocks to examine their abilities to remove gallic acid, a representative phenolic acid. Biochar, which was prepared from wood meal soaked with H3PO4 (1:1.5, w/w) and pyrolyzed at 400 °C (symbolized as WP400), exhibited the highest adsorption capacities of gallic acids and other phenolic acids. The mechanisms of phenolic acid removal by WP400 were evaluated via experimental and spectroscopic investigations to elucidate the notable adsorption capacity of WP400. The adsorption of gallic acids was pH-dependent and followed a pseudo-second-order kinetic model. The combination of high surface area, the existence of O-containing groups, and the enhancement of H bonds between CC groups and phenolic acids may contribute to the high adsorption capacity of WP400. In a pot experiment, we found that celery growth was promoted with the addition of 0.3% (w/w) WP400 to soils that were continuously monocropped with celery. A large decrease in the water-soluble phenolic compound by more than 40% may be responsible for the results. However, WP400 scavenged nitrate, and this study showed that the synergistic actions of WP400 and nutrients exhibited the greatest efficiencies in mitigating the continuous cropping obstacles of celery.

Influence of Increased Radiation Background on Antioxidative Responses of Helianthus tuberosus L.

As a result of the accident at the Chornobyl Nuclear Power Plant, significant territories were exposed to ionizing radiation. Some isotopes, such as 137Cs, are capable of making a significant impact on living organisms in the long-term perspective. The generation of reactive oxygen species is one mechanism by which ionizing radiation affects living organisms, initiating mechanisms of antioxidant protection. In this article, the effect of increased ionizing radiation on the content of non-enzymatic antioxidants and the activity of antioxidant defense enzymes of Helianthus tuberosum L. was studied. This plant is widely distributed in Europe and characterized by high adaptability to abiotic factors. We found that the activity of antioxidant defense enzymes, such as catalase and peroxidase, weakly correlated with radiation exposure. The activity of ascorbate peroxidase, on the contrary, is strongly positively correlated with radiation exposure. The samples growing on the territory with constant low exposure to ionizing radiation were also characterized by an increased concentration of ascorbic acid and water-soluble phenolic compounds compared to the controls. This study may be useful for understanding the mechanisms underlying the adaptive reactions of plants under prolonged exposure to ionizing radiation.

Effect of <i>Bacillus thuringiensis</i> strains on growth and metabolic processes in <i>Pisum sativum</i> L. sprouts

Although the entomopathogenic bacteria Bacillus thuringiensis Berliner are well-known bio-agents for regulating the population of leaf-eating pests of agricultural and ornamental crops, other agricultural properties of this microorganism are promising. In this work, the growth-stimulating effect of entomopathogenic strains of B. thuringiensis on Deviz pea plants was studied. The entomopathogenic strains B. thuringiensis 685, 926 and 109-C obtained from the Crimean Collection of Microorganisms of the Crimean Agricultural Research Institute, registered online (http://www.ckp-rf.ru) with number 507484, were used as research material. The morphometric parameters of pea sprouts were evaluated following standard methods. Biochemical parameters of pea sprouts were determined for 10-day-old sprouts. The amylase activity of pea sprouts was determined by photocalorimetry; total acidity was measured by titration using 0.1 n NaOH solution; total water-soluble phenolic compounds were determined by Leventhal titrimetric method. It was found that liquid spore culture of strains B. thuringiensis 685, 926 and 109-C had a stimulating effect on the length of root and stem and the weight of 10-day-old sprouts of Deviz pea variety. Treatment with a spore suspension of all tested strains B. thuringiensis led to an increase in the content of organic acids in the sprouts by an average of 12.4% compared with that of the control. Maximum stimulating effect on amylolytic activity and synthesis of phenolic compounds in Deviz pea sprouts was achieved by treating with a spore suspension of the strain B. thuringiensis 926. The amylase activity increased on average by 41.5% when compared to that of the control, while the total content of phenolic compounds in this experiment was 2.3 times higher than that of the control. Therefore, in light of the entomopathogenic properties and the obtained data on the growth-stimulating activity of the strains of B. thuringiensis, it can be concluded that these bacteria have additional potential for their use in agriculture as a bio-agent for plant protection having a complex action.

Water-soluble phenolic compounds and their putative antioxidant activities in the seed coats from different lentil (Lens culinaris) genotypes

The seed coat is a major byproduct of lentil processing with potential as a sustainable source of antioxidant polyphenols. Profiles of water-soluble phenolic compounds and antioxidant activities of seven genotypes of lentil which includes both normal-tannin and low-tannin seed coats were investigated. Antioxidant activities were assessed using four antioxidant assays, and phenolic compounds were quantified using liquid chromatography mass spectrometry (LC-MS). Total phenolic content (TPC) varied significantly among genotypes and ranged between 1519 ± 140 and 6502 ± 154 μg/g. Thirty phenolic compounds were identified with kaempferol tetraglycoside, catechin-3-glucoside and procyanidins being the dominant compounds in normal-tannin seed coats. Kaempferol tetraglycoside predominated (80–90%) in low-tannin seed coats. Antioxidant activities strongly correlated with TPC (r > 0.93) with a 6–9 times higher activity in normal-tannin than that of low-tannin lentils. Without flavan-3-ols and procyanidins, low-tannin seed coat may not exert strong antioxidant potential, whereas normal-tannin seed coat contains water-extractable natural phenolic compounds with promising antioxidant potential.

An Evaluation of the Kinetic Properties Controlling the Combined Chemical and Biological Treatment of Toxic Recalcitrant Organic Compounds from Aqueous Solution

Due to their high toxicity, propensity for cancer, teratogenicity, mutagenicity, and genotoxicity, hazardous water-soluble phenolic compounds must be controlled immediately. In this study, a model was created to simulate the degradation of harmful recalcitrant organic compounds in a combined chemical and biological treatment system. The parameter estimations with inhibition coefficient (Haldane model) and without inhibition coefficient (Michaelis-Menten model) were assessed over a wide range of initial concentrations using the Monod-like model. The kinetic parameters were optimized using AQUASIM 2.0 software. At a 50 mg·L−1 feed concentration of 4-chlorophenol, removal efficiencies of more than 98% were attained under these circumstances. The primary kinetic parameters were identified and their values models were validated using the fitted parameter values that reached a good degree of agreement (R2 = 0.998). We may better comprehend and make use of the complex phenolic compounds’ biodegradation processes, such as progress optimization and scale-up, by understanding the mechanisms of substrate interaction and the new kinetic models that have been provided in this work.

The Critical Role of Phenolics on Gasification of Biomass Hydrolysate

The study was designed to solubilize sorghum by water extraction and investigate the effect of phenolics depending on the time in sorghum hydrolysate for hydrogen gas production by aqueous-phase reforming. The Folin-Ciocalteau method was used to determine the total water soluble phenolics of the sorghum hydrolysate. There were no significant changes in the total amount of phenolic compounds during the first weeks. It was observed that the total amount of water soluble phenolic compounds of sorghum hydrolysates showed changes monthly (300-400 ppm). The gas volume produced reached up to 40-50 mL was obtained when the hydrolysates were gasified. APR of biomass hydrolysates in the presence of a reforming catalyst (Pt 5% on activated carbon) produced various amount of gas mixture which consisted of H2, CH4 and CO2 gases. The results showed that the decrease in total water soluble phenolics of sorghum hydrolysate had no significant effect on gasification, depending on the time.

Valorization of the residual bagasse of Mexican oregano (Lippia graveolens HBK) by obtaining fractions enriched in pinocembrin


 Mexican oregano (Lippia graveolens HBK) constitutes a spice of great commercial value mainly due to the presence of thymol and carvacrol, volatile fat-soluble compounds contained in its essential oil. However, little use has been made of its high content of water-soluble phenolic compounds, with proven antioxidant capacities. Among them, it stands out its high content of pinocembrin, flavanone with properties of great nutritional importance and for health due to its protective activity against cerebral ischemia. Mexico ranks second as a world producer of Mexican oregano. During the extractive process of the essential oil derived from its leaf, a large amount of solid waste rich in flavonoids is generated, which is minimally used and even becomes a source of contamination due to its poor disposal as waste. In order to value this agro-industrial waste, it was characterized by determining the content of total phenols, antioxidant activity (DHHP) and content of pinocembrin, observing a higher content of pinocembrin in the extract of oregano without essential oil (0.766 mg / ml) with respect to that corresponding to oregano without treatment (0.659 mg / ml). The results suggest that the residual bagasse from the extraction of the essential oil can be used with great potential due to its high content of polyphenols, antioxidant capacity and pinocembrin (27.93 mg / g BS). To achieve the concentration of pinocembrin, two separation methods were evaluated: chromatographic column with silica gel (hydrophilic) and separation with automated extraction in hydrophobic solid phase (Ultra C18) with pinocembrin recovery efficiencies of 56.6 and 90.1 %, respectively, being able to generate products enriched in pinocembrin with a 74.8 % purity. This work contributes to the potential development of new products and waste recovery processes in the growing natural essential oil extraction industry.

Tannins in Foods: Nutritional Implications and Processing Effects of Hydrothermal Techniques on Underutilized Hard-to-Cook Legume Seeds-A Review.

Tannins, water-soluble phenolic compounds, have been reported to have the ability to form complexes with nutritionally important nutrients such as protein and mineral elements thereby making them unavailable for absorption and utilization. Toxicity of tannin has been demonstrated in experimental animals although no deleterious effect of ingestion of legume tannin on human physiology has been reported. This report highlights the processing effects of soaking and hydrothermal techniques on some underutilised hard-to-cook legume crops and the importance of tannin in legume nutrition. Soaking and hydrothermal processing reduce the tannin content of processed legume seeds and hence improve the availability of protein and mineral elements. In view of the recent findings of the health benefits, classification of tannin which is traditionally regarded as an antinutrient should be reconsidered. Provision of these information will enhance knowledge of legume nutrition and economic utility. Increasing consumption of underutilized nutritionally important legume seeds, it is hoped, will alleviate the problem of protein energy malnutrition in many developing nations.

The role of antioxidants in the mechanisms of adaptation of <i>Poa Pratensis </i>L. under the influence of wooden plants

The article analyzes the results on the content of peroxidase, phenolic compounds and ascorbic acid in the leaves of meadow bluegrass during the growing season under plantations of woody plants (scots pine and ash-leaved maple). The peroxidase activity in the leaves of plant samples was determined by the method of A.N. Boyarkin, the content of ascorbic acid - by the titrimetric method using sodium 2,6-dichlorophenolindophenol, water-soluble phenolic compounds - by the Leventhal-Neubauer method. Mutual regulation of the plant antioxidant defense system was established, expressed in an increase in the level of ascorbic acid, but a decrease in the activity of peroxidase and phenolic compounds. The accumulation of metabolites in the studied plants varied depending on the phases of the growing season and growing conditions. Scots pine had the greatest inhibitory effect on the studied species than ash-leaved maple. The results obtained can be used to assess the state of the ground cover and the structure of the phytocenosis.

Formation and evolution of brown carbon during aqueous-phase nitrate-mediated photooxidation of guaiacol and 5-nitroguaiacol

Light absorbing organic aerosols, which are commonly referred to as brown carbon (BrC), have important climate impacts. Phenolic compounds are a class of aromatic compounds that are known BrC precursors. Inorganic nitrate is a ubiquitous component of atmospheric aerosols, clouds, and fog. The photolysis of inorganic nitrate in atmospheric aqueous phases generates a variety of reactive oxygen species and reactive nitrogen species that can facilitate the photooxidation of organic compounds to form BrC. In this study, we investigated the formation and evolution of BrC from the aqueous-phase photooxidation of guaiacol and 5-nitroguaiacol initiated by inorganic nitrate photolysis. Guaiacol and 5-nitroguaiacol are two water-soluble phenolic compounds that are commonly found in fossil fuel and biomass burning emissions. Upon illumination in the presence of sodium nitrate, guaiacol and 5-nitroguaiacol reacted rapidly to form BrC. The reaction rates and quantities of BrC formed depended on the initial sodium nitrate concentration. The reaction rates of guaiacol were substantially faster than those of 5-nitroguaiacol. The electron-withdrawing nitro functional group on 5-nitroguaiacol's aromatic ring likely had a deactivating effect on the ring's reactivity, which contributed to 5-nitroguaiacol's lower reactivity compared to guaiacol. The major products produced during the initial stages of photooxidation were formed by the addition of nitro and/or nitroso groups to guaiacol and 5-nitroguaiacol. These products likely strongly absorbed near-UV and/or visible light, which led to an observed increase in light absorption (i.e., photo-enhancement) in the near-UV and visible range. Greater photo-enhancement was observed during the nitrate-mediated photooxidation of guaiacol. This indicated that the presence of nitro functional group(s) on the aromatic ring of phenolic compounds will impact the extent of photo-enhancement during BrC formation. Further photooxidation caused the initial products to fragment into smaller molecules that do not absorb near-UV and visible light. This resulted in an observed decrease in light absorption (i.e., photo-bleaching). These results highlight how aqueous-phase inorganic nitrate photolysis can drive the formation of BrC by facilitating the photooxidation of organic compounds.

High-Performance liquid chromatography-tandem mass spectrometry with polar C18 for rapid quantification of anthocyanin and flavonoid in black soybean extracts

ABSTRACT Black soybean (Glycine max L.) is one of the most popular crops with various application in the world. Its seed coat contains various natural pigments compounds such as anthocyanin and flavonoid. In this study, we optimize the extraction conditions of eight polyphenols from whole of black soybean and seed coat, evaluate their extraction effect, and separation resolution at different pH-range. The multiple reaction monitoring (MRM) method was analyzed by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) with simultaneous positive and negative electrospray ionization in a single analytical run. Eight polyphenols were separated within 9 minutes of run time with LC-MS/MS operated mode. The calibration graphs were linear over the concentration ranges of 0.01 to 1 mg/L for all polyphenol. Regression coefficients were in the range > 0.99. The limit of detection value, calculated from the blank tests based on 3σ, was 1 µg/L for all polyphenol. The RSD values corresponding to the intra-day and inter-day repeatability were lower than 11% and accuracies between 85-115%. It is shown that the modified solvent system that applied in LC-MS/MS detection could be developed as a useful tool for the study of water-soluble phenolic compounds.

KOMPOSISI SENYAWA FENOL DAN POTENSI ANTIOKSIDAN DARI KACANG-KACANGAN: REVIEW

Legumes are good dietary source of bioactive phenolic compounds which play significant roles in many physiological as well as metabolic processes. Flavonoids, phenolic acids and condensed tannins are the main phenolic compounds that are provide in legume seeds. Majority of the phenolic compounds are serving in the legume seed coats. The majority of seed coat of legume seeds are phenolic acids and flavonoids (mainly catechins and procyanidins). Gallic and protocatechuic acids are common in kidney bean and mung bean. Almost 70% of total phenolic compounds in lentils and cranberry beans (seed coat) are catechins and procyanidins. The antioxidant activity of phenolic compounds is in lineal intercourse with their chemical structures such as number as well as position of the hydroxyl groups. Processing mostly conducts to the alleviation of phenolic compounds in legumes because of chemical rearrangements. Phenolic content also lessen due to leaching of water-soluble phenolic compounds into the cooking water. This review provides comprehensive information of phenolic compounds identified in grain legume seeds along with discussing their antioxidant.
 Keywords: antioxidant activity, legume seeds, phenolic compounds, processing

Rosmarinic acid exerts an antagonistic effect on nonalcoholic fatty liver disease by regulating the YAP1/TAZ-PPARγ/PGC-1α signaling pathway.

Rosmarinic acid (RA) is a water-soluble phenolic compound extracted from Boraginaceae and Lamiaceae. This study was designed to investigate the role and mechanism of action of RA in improving nonalcoholic fatty liver disease (NAFLD). Male SD rats maintained on a high fat diet and L02 cells stimulated with oleic acid were treated with RA. Our results showed that RA significantly reduced total cholesterol, triglycerides, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, and malondialdehyde levels and increased high-density lipoprotein cholesterol, superoxide dismutase and adenosine triphosphate levels both in vivo and in vitro. Hematoxylin and eosin staining and oil red O staining showed that RA had a good lipid-lowering effect and substantial protective effects on liver injury. Transmission electron microscopy and JC-1 fluorescence results showed that RA could improve mitochondrial damage in hepatocytes. Additionally, flow cytometry results indicated that RA inhibited ROS generation and apoptosis in L02 cells. The impaired hepatocytes were restored by using RA in NAFLD models characterized by down-regulating YAP1 and TAZ, meanwhile up-regulating PPARγ and PGC-1α. When YAP1 was over-expressed, RA reduced the expression of YAP1; however, the action of RA was significantly blocked by silencing YAP1. The experimental results indicated that RA markedly alleviated NAFLD by repairing mitochondrial damage and regulating the YAP1/TAZ-PPARγ/PGC-1α signaling pathway.

Distribution of enzymatic and alkaline oxidative activities of phenolic compounds in plants

In this study, we screened 287 plant tissue samples from 175 plant species for their phenolic profiles. The samples were oxidized enzymatically in planta or at high pH in vitro to determine how these two oxidative conditions would alter the initial polyphenol profiles of the plant. Compounds that contained a pyrogallol or dihydroxyphenethyl group were highly active at pH 10. Enzymatic oxidation favored compounds that contained a catechol group, whereas compounds containing a pyrogallol group or monohydroxysubstituted phenolic moieties at most were oxidized less frequently. This study gives a broad overview of the distribution and alkaline oxidative activities of water-soluble phenolic compounds in plants as well as the enzymatic oxidative activities of various plant tissues.

Therapeutic potential of phenylethanoid glycosides: A systematic review.

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure-activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.

Water-soluble phenolic compounds and their anti-HIV-1 activities from the leaves of Cyclocarya paliurus

Eight phenolic compounds including five glucuronides were isolated from the leaves of Cyclocarya paliurus (Batal.) Ijinskaja, which is used as a source of tea. Their structures were characterized by spectroscopic methods. The results of biological assay showed that compounds 1 and 5 had good activities against HIV-1 induced cytopathic effects in C8166 lymphocyte at non-cytotoxic concentrations, with EC50 values of 31.74 and 10.76 μM, and therapeutic index (TI) values of >13.02 and 25.46, respectively. Relationship between molecular structures and their bioactivities was discussed.