Study on the potential hypoglycemic flavonoids in Abrus precatorius leaves: purification process, quality profile and activity mechanisms by transcriptomics and network pharmacology.

The aim of the study was to investigate the relationship between flavonoids in Abrus precatorius leaves (APL) and their hypoglycaemic effects, which have not been studied before. An efficient purification process, transcriptomics and network pharmacology analysis were applied for the first time. High-performance liquid chromatography (HPLC) was used to determine the content of total flavonoids. The results showed that D101 resin was most suitable for purification of flavonoids of APL, which could increase its purity from 25.2% to 85.2% and achieve a recovery rate of 86.9%. The analysis of transcriptomics and network pharmacology revealed that flavonoids of APL could play a hypoglycaemic role by regulating 31 targets through AGE-RAGE and other signal pathways. Flavonoids of APL could exert hydroglycaemic effects by inhibiting AGEs, α-glucosidase and DPPH. This study provides a solid basis for hypoglycaemic product development and in-depth research of flavonoids in APL.

Chitosan-based layer-by-layer edible coatings application for the preservation of mandarin fruit bioactive compounds and organic acids.

The layer-by-layer application of biopolymeric coatings to mandarin fruits as a postharvest treatment to improve fruit coating efficacy has been reported. A single 1 % (w/v) chitosan application was evaluated, and polyelectrolyte complexes such as 1.5 % (w/v) alginate/chitosan, 1 % (w/v) hydroxypropyl methylcellulose/chitosan, and 0.2 % (w/v) locust bean gum/chitosan were applied to mandarin fruits. The quality of coated mandarin fruits was observed at temperatures: 20 ± 2 °C (up to 10 days) and 5 °C (up to 28 days). Changes in the fruit metabolism were observed by evaluating bioactive compounds (polyphenolic compounds and flavonoids), antioxidant activity, and organic acids during the preservation of mandarin fruits. All of the tested combinations of layer-by-layer coatings significantly impacted the quality of mandarin fruits throughout storage, both at room temperature and cold storage, respectively. The overall best performance was observed for a layer-by-layer hydroxypropyl methylcellulose/chitosan coating in terms of visual aspects, bioactive compounds, antioxidant activity, and organic acids content.

A Beta/ZSM-22 Zeolites-Based-Mixed Matrix Solid-Phase Dispersion Method for the Simultaneous Extraction and Determination of Eight Compounds with Different Polarities in Viticis Fructus by High-Performance Liquid Chromatography.

Viticis Fructus (VF) was named Manjingzi as a commonly used traditional Chinese medicine (TCM) targeting various pains and inflammation for more than 2000 years. To guarantee the quality of Viticis Fructus, a simple, quick and eco-friendly Beta/ZSM-22 zeolites-based-mixed matrix solid-phase dispersion method (B/Z-MMSPD) was established for simultaneous extraction and determination of eight compounds (two phenolic acids, two iridoid glycosides, vanillin and three flavonoids) with different polarities from Viticis Fructus by high performance liquid chromatography coupled with a diode array detector (HPLC-DAD). Beta and ZSM-22 were mixed as the sorbent. Water, tetrahydrofuran and methanol were blended with certain ratio as the eluent. Several parameters including types of sorbents, mass ratio of Beta to ZSM-22, mass ratio of matrix to sorbent, grinding time, types, concentration and volume of eluent were optimized. The recoveries of eight analytes were within the range of 95.0%-105% (RSDs ≤ 4.13%). The limits of detection and limits of quantitation ranged from 0.5 to 5.5 µg/g and from 1.5 to 16 µg/g, respectively. Compared to the traditional extract methods, it was a simple, rapid, efficient and green method. The results demonstrated that a simple, rapid, efficient and green B/Z-MMSPD was developed for the simultaneous extraction and determination of eight target analytes with different polarities for quality control of Viticis Fructus.

Suppression of UV-B stress induced flavonoids by biotic stress: Is there reciprocal crosstalk?

Plants respond to abiotic UV-B stress with enhanced expression of genes for flavonoid production, especially the key-enzyme chalcone synthase (CHS). Some flavonoids are antioxidative, antimicrobial and/or UV-B protective secondary metabolites. However, when plants are challenged with concomitant biotic stress (simulated e.g. by the bacterial peptide flg22, which induces MAMP triggered immunity, MTI), the production of flavonoids is strongly suppressed in both Arabidopsis thaliana cell cultures and plants. On the other hand, flg22 induces the production of defense related compounds, such as the phytoalexin scopoletin, as well as lignin, a structural barrier thought to restrict pathogen spread within the host tissue. Since all these metabolites require the precursor phenylalanine for their production, suppression of the flavonoid production appears to allow the plant to focus its secondary metabolism on the production of pathogen defense related compounds during MTI. Interestingly, several flavonoids have been reported to display anti-microbial activities. For example, the plant flavonoid phloretin targets the Pseudomonas syringae virulence factors flagella and type 3 secretion system. That is, suppression of flavonoid synthesis during MTI might have also negative side-effects on the pathogen defense. To clarify this issue, we deployed an Arabidopsis flavonoid mutant and obtained genetic evidence that flavonoids indeed contribute to ward off the virulent bacterial pathogen Pseudomonas syringae pv. tomato (Pst) DC3000. Finally, we show that UV-B attenuates expression of the flg22 receptor FLS2, indicating that there is negative and reciprocal interaction between this abiotic stress and the plant-pathogen defense responses.

Effect of training system and climate conditions on phytochemicals of Passiflora setacea, a wild Passiflora from Brazilian savannah.

Passiflora setacea is a Brazilian savannah fruit known as a good source of phytochemicals. The phytochemical composition is influenced by environmental factors and management techniques such as training system. This study aimed to evaluate the influence of training system (espalier or trellis) and environmental factors (temperature, precipitation and sunlight exposure) on antioxidant capacity and bioactive composition of P. setacea pulp. Total phenolic compounds (TP), proantocyanidins (PA), total flavonoids (TF), vitamin C and total antioxidant activity were analyzed. Five flavonoids (orientin, isoorientin, vitexin, isovitexin and hesperetin) were determined by HPLC-DAD, using calibration curves. Training system presented no effects on TP, PA, TF and antioxidant activity, whereas rainy season year 2 increased FRAP values, TF, orientin, isovitexin and hesperetin content, which could be associate to climate stressful condition leading to higher levels of these compounds.

Identification of chemical compositions in Chenxiang Huaqi Pills by UPLC-Q-TOF/MS / 中草药

Objective: To analyze the main chemical constituents of traditional Chinese medicine compound Chenxiang Huaqi Pills by using UPLC-Q-TOF/MS technology. Methods: The separation was performed on Phenomenex Kinetex C18 column (100 mm×4.6 mm, 2.7 μm), and the gradient elution of acetonitrile-0.1% formic acid was used as mobile phase at a flow rate of 0.8 mL/min. The data was collected by the positive and negative ion modes using Q-TOF/MS and ESI source. The main chemical constituents of Chenxiang Huaqi Pills were identified according to the exact molecular mass, the cleavage fragments of MS/MS, the literature data, and the reference control. Results: A total of 73 chemical components were separated and identified in Chenxiang Huaqi Pills, including 36 flavonoids, 16 2-(2-phenylethyl) chromones, 7 triterpenoid saponins, 2 sesquiterpene lactones, and 12 other components. Conclusion: This study showed that UPLC-Q-TOF/MS technology provided a simple, rapid, and accurate method for the identification of chemical constituents in Chenxiang Huaqi Pills, which provided a new technology method for the pharmacological basis and quality control of Chenxiang Huaqi Pills.

Evaluation of bioactive flavonoids and antioxidant activity in Pericarpium Citri Reticulatae (Citrus reticulata 'Chachi') during storage.

A simple and accurate method using high performance liquid chromatography (HPLC) with dual wavelength detection was developed to simultaneously determine the contents of one flavanone glycoside (hesperidin) and five polymethoxylated flavones (PMFs: sinensetin, 4',5,7,8-tetramethoxyflavone, nobiletin, tangeretin and 5-O-desmethyl nobiletin) in Pericarpium Citri Reticulatae (Citrus reticulata 'Chachi') ('Chachi' PCR). By modifying the mobile phase compositions and detection wavelengths, an optimal HPLC condition was obtained, under which the calibration curves of all six compounds exhibited good linearity (R2>0.99). For all the tested compounds, the relative standard deviation (RSD) was less than 4%, and the accuracy ranged from 97.58 to 103.2%. The developed method was successfully applied to monitor the changes in the contents of six flavonoids in 'Chachi' PCR during storage at 25°C, over a three year period. Color parameters and antioxidant capacity were also determined to evaluate the sample quality. The contents of hesperidin decreased while all the polymethoxylated flavones and antioxidant activities increased throughout the storage period, demonstrating that polymethoxylated flavones could be used as indices for the quality change of Chachi' PCR during storage. The results from this study suggest that the longer storage periods increased the quality of PCR.

Antioxidant activity and phenolic profile of various morphological parts of underutilised Baccaurea angulata fruit.

Baccaurea angulata is an underutilised tropical fruit of Borneo Island of Malaysia. The effect of solvents was examined on yield, total phenolic (TPC), total flavonoids (TFC), total carotene content (TCC), free radical scavenging activities and lipid peroxidation inhibition activities. The results indicated that the pulp (edible portion) had the highest yield, while methanol extracts were significantly (p < 0.01) found to contain higher TPC, TFC and TCC than phosphate buffered saline (PBS) extracts for all the fruits parts. The methanol extracts also showed remarkable antiradical activity and significant lipid peroxidation inhibition activities, with their IC50 results highly comparable to that of commercial blueberry. The variations in the results among the extracts suggest different interactions, such as negative or antagonistic (interference), additive and synergistic effect interactions. The study indicated that B. angulata like other underutilised tropical fruits contained remarkable primary antioxidants. Thus, the fruit has the potential to be sources of antioxidant components.

Antioxidant, antimicrobial, antitumor, and cytotoxic activities of an important medicinal plant (Euphorbia royleana) from Pakistan.

The aim of present study was to evaluate antioxidant, antimicrobial, and antitumor activities of methanol, hexane, and aqueous extracts of fresh Euphorbia royleana. Total phenolic and flavonoid contents were estimated as gallic acid and querectin equivalents, respectively. Antioxidant activity was assessed by scavenging of free 2,2'- diphenyl-1-picrylhydrazyl radicals and reduction of ferric ions, and it was observed that inhibition values increase linearly with increase in concentration of extract. The results of ferric reducing antioxidant power assay showed that hexane extract has maximum ferric reducing power (12.70 ± 0.49 mg gallic acid equivalents/g of plant extract). Maximum phenolic (47.47 ± 0.71 µg gallic acid equivalents/mg of plant extract) and flavonoid (63.68 ± 0.43 µg querectin equivalents/mg of plant extract) contents were also found in the hexane extract. Furthermore, we examined antimicrobial activity of the three extracts (methanol, hexane, aqueous) against a panel of microorganisms (Escherichia coli, Bacillus subtillis, Pasteurella multocida, Aspergillus niger, and Fusarium solani) by disc-diffusion assay, and found the hexane extract to be the best antimicrobial agent. Hexane extract was also observed as to be most effective in a potato disc assay. As hexane extract showed potent activity in all the investigated assays, it was targeted for cytotoxic assessment. Maximum cytotoxicity (61.66%) by hexane extract was found at 800 µg/mL. It is concluded that investigated extracts have potential for isolation of antioxidant and antimicrobial compounds for the pharmaceutical industry.

Anti-Inflammatory Effect of Quercetagetin, an Active Component of Immature Citrus unshiu, in HaCaT Human Keratinocytes.

Citrus fruit contain various flavonoids that have multiple biological activities. However, the content of these flavonoids are changed during maturation and immature Citrus is known to contain larger amounts than mature. Chemokines are significant mediators for cell migration, while thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well known as the typical inflammatory chemokines in atopic dermatitis (AD), a pruritic and chronic inflammatory skin disease. We reported recently that the EtOH extract of immature Citrus unshiu inhibits TARC and MDC production. Therefore, we investigated the activity of flavonoids contained in immature Citrus on TARC and MDC levels. As a result, among the various flavonoids, quercetagetin has stronger inhibitory effects on the protein and mRNA expression of TARC and MDC than other flavonoids. Quercetagetin particularly has better activity on TARC and MDC level than quercetin. In HPLC analysis, the standard peak of quercetagetin matches the peaks of extract of immature C. unshiu. This suggests that quercetagetin is an anti-inflammatory component in immature C. unshiu.

Anti-Inflammatory Effect of Quercetagetin, an Active Component of Immature Citrus unshiu, in HaCaT Human Keratinocytes

Citrus fruit contain various flavonoids that have multiple biological activities. However, the content of these flavonoids are changed during maturation and immature Citrus is known to contain larger amounts than mature. Chemokines are significant mediators for cell migration, while thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well known as the typical inflammatory chemokines in atopic dermatitis (AD), a pruritic and chronic inflammatory skin disease. We reported recently that the EtOH extract of immature Citrus unshiu inhibits TARC and MDC production. Therefore, we investigated the activity of flavonoids contained in immature Citrus on TARC and MDC levels. As a result, among the various flavonoids, quercetagetin has stronger inhibitory effects on the protein and mRNA expression of TARC and MDC than other flavonoids. Quercetagetin particularly has better activity on TARC and MDC level than quercetin. In HPLC analysis, the standard peak of quercetagetin matches the peaks of extract of immature C. unshiu. This suggests that quercetagetin is an anti-inflammatory component in immature C. unshiu.

Antioxidant activities of bark extract from mangroves, Bruguiera cylindrica (L.) Blume and Ceriops decandra Perr.

OBJECTIVES: The antioxidant activities of two Indian mangrove plants, Bruguiera cylindrica and Ceriops decandra, were investigated. MATERIALS AND METHODS: Total phenolics and total flavonoid contents of the mangroves were determined using folin-ciocalteu reagent method and aluminium chloride method, respectively. Antioxidant capacity was assessed by the following methods: 1,1-diphenyl-2-picryl hydroxyl (DPPH.) quenching assay; 2,2'- azinobis-3-ethylbenzothiozoline-6-sulfonic acid (ABTS.(+)) cation decolorization test; scavenging capacity towards hydroxyl ion radicals (.OH); reductive capacity; and antihemolytic activity. RESULTS: The mangroves yielded 233.3 ± 0.062 and 283.31 ± 0.04 mg gallic acid equivalent/g phenolic contents and 11.6 ± 0.12 and 15.1 ± 0.02 mg quercetin equivalent/g flavonoid contents. The methanol extracts of both mangroves exhibited high antiradical activity against DPPH., ABTS.(+), and .OH radicals. The reductive capacity of the extracts increased with increasing concentration of samples. The extracts also inhibited H(2)O(2) induced hemolysis in cow blood erythrocytes. The antioxidant activities were found stronger than that of the reference standard, butylated hydroxy toluene (BHT). The antioxidant activity of mangrove plants was correlated with total phenolics and flavonoid contents. CONCLUSION: Both plants can be considered as good sources of natural antioxidants for medicinal uses. Further studies are necessary to isolate active principles responsible for the overall antioxidant activity of the extracts.

Phytochemical investigation, cytotoxicity and free radical scavenging activities of non-polar fractions of Acalypha hispida (leaves and twigs).

Free radicals are involved in the process of lipid peroxidation and play a cardinal role in numerous chronic diseases like cancer, coronary heart disease and ageing. Thus the ability to scavenge free radicals in order to minimize oxidative damage to living cells is very important. The hexane extract of Acalypha hispida (Burn F.) was screened for phytochemical constituents and was found to contain flavonoids, carbohydrates, phenols and alkaloids. Fractions obtained from chromatographic separation were screened for free radical scavenging activities using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and hydrogen peroxide. Out of the sixteen pooled fractions (S1-S16) screened, compounds S10 (91.8 %), S11 (93.8 %), S14 (92.5 %) and S15 (91.4 %) at a concentration of 0.1 mg/ml had significant antioxidant activities when compared to the known antioxidant ascorbic acid (90.9 %). However, in the analysis using hydrogen peroxide, S1 (99.5 %), S9 (99.2 %), S10 (95.4 %),S11 (95.8 %) and S15 (95.6 %) gave better activity than ascorbic acid (94.8 %), while only S1 and S9 were more effective than butylated hydroxylanisole (98.9 %) and α-Tocopherol (99.1 %) at the same concentration. The cytotoxicity analysis using the Brine Shrimp lethality test gave LC50 values greater than 1000 µg/ml for some of the fractions indicating very low level of toxicity. The better scavenging activity of A. hispida could be linked to the presence of secondary plant products like flavonoids and phenols, which have the ability to scavenge hydroxyl radicals, superoxide anions and lipid peroxy radicals.

Inhibitory effects of total flavonoids of scutellaria baicalensis georgi on S_(180),Hep-A-22 and Bcap-37 tumor cells / 吉林大学学报(医学版)

Objective To study the inhibitory effects of total flavonoids of scutellaria baicalensis georgi(TFSB) on S180,Hep-A-22 and Bcap-37 tumor cell proliferation in vitro and on S180,Hep-A-22 in mice bearing tumor in vivo.Methods In vitro,S180,Hep-A-22 and Bcap-37 cells were divided into control group and TFSB groups(12.5,25.0,50.0,100.0 mg?L-1).The inhibitory effects of TFSB on proliferation of S180 and Hep-A-22 were measured by XTT colorimetric assay,and Bcap-37 cells were measured by MTT colorimetric assay.In vivo,the mice bearing tumor were divided into control group,CTX group(30 mg?kg-1),high,middle,low doses TFSB groups(200,100,50 mg?kg-1).After the mice bearing S180 and Hep-A-22 tumor cells were treated with TFSB for 15 d,the tumor weights were measured,the inhibitory rates of S180 and Hep-A-22 were calculated and survival of Hep-A22 was measured after administration of TFSB for 10 d.Results TFSB inhibited the proliferation of S180,Hep-A-22 and Bcap-37 cells,IC50 values were 16.04,17.74 and 9.05 mg?L-1,respectively.The tumor weight of mice bearing S180 and Hep-A-22 cells in TFSB groups(200,100,50mg?kg-1) were lowered than that in control(P