Effect of Astragalus sinicus L. seed extract on antioxidant activity

Effects of roasting conditions on Korean rice wine (Makgeolli) with licorice (Glycyrrhiza uralensis Fischer)

The present study investigated the effect of roasting process (temperature: 150, 180, and 210 °C; time: 10, 20, and 30 min) of licorice on the browning index (BI), total flavonoid content (TFC), and antioxidant activity for ingredient of Makgeolli. The antioxidant activity was measured by assaying DPPH radical scavenging activity (DPPH·IC₅₀) and Trolox equivalent antioxidant capacity (TEAC). In addition, the quality characteristics of Makgeolli with different amount (0%, 6%, 12%, and 18%) of roasted licorice extract (RLE) were measured comparison to un-roasted licorice extract (ULE). When superimposing the contour plots of the responses in which the limits of each response were determined, the optimum conditions for roasting licorice were 178 °C for 24 min. Moreover, results revealed that Makgeolli with 12% RLE under optimum roasting condition was superior with respect to antioxidant activity and more acceptable based on sensory properties than ULE.

Comprehensive evaluation of two Astragalus species (A. campylosema and A. hirsutus) based on biological, toxicological properties and chemical profiling

Astragalus L. (Fabaceae) is an important genus with numerous species having various traditional medicinal uses making them of interest for scientific investigations to ascertain their therapeutic benefits. In the present study, the quantitative polyphenolic profiles of methanolic extracts from different parts (leaves, flowers, and roots) of two endemic Astragalus species growing in Turkey, i.e. A. campylosema Boiss. and A. hirsutus Vahl were determined, along with their antioxidant and enzyme inhibitory properties. A. campylosema and A. hirsutus extracts showed varying total phenolic (25.80-40.60 and18.59-29.46 mg GAE/g, respectively) and total flavonoid (11.21-105.91 and 16.06-131.91 mg RE/g, respectively) contents. HPLC-MS/MS revealed rutin to be the predominant phenolic compound in all the extracts of A. campylosema and leaf extract of A. hirsutus (133.53-752.42 μg g^-1), while hyperoside was the major one in the flower and root extracts of A. hirsutus (2014.07 and 123.13 μg g^-1, respectively). In DPPH and ABTS assays, radical scavenging capacity was demonstrated by all extracts of A. campylosema (47.13-48.10 and 87.03-115.36 mg TE/g, respectively) and A. hirsutus (17.82-38.67 and 47.84-57.29 mg TE/g, respectively). Reducing activity was also displayed by the extracts in CUPRAC and FRAP assays (A. campylosema: 83.06-135.20 and 59.15-90.19 mg TE/g, respectively; A. hirsutus: 53.02-83.42 and 31.25-43.25 mg TE/g, respectively). All extracts were also found to act as metal chelators (12.32-21.45 mg EDTAE/g) and exhibited total antioxidant capacity ranging from 1.16 to 1.60 mmol TE/g, in phosphomolybdenum assay. Acetyl- and butyryl-cholinesterase inhibitory effects were observed by all the extracts of the two species (1.56-4.99 mg GALAE/g). Anti-hyperpigmentation potential by inhibiting tyrosinase (54.55-67.35 mg KAE/g) was reported as well. Carbohydrate hydrolyzing enzymes, amylase and glucosidase were also inhibited (0.22-1.03 mmol ACAE/g). Overall, A. campylosema extracts showed relatively better antioxidant and enzyme inhibitory potentials compared to A. hirsutus extracts. Strikingly, A. hirsutus extracts was found to have higher AGE inhibition activity than A. campylosema. Although the cytotoxic effect of three different organs obtained from A. campylosema and A. hirsutus increased depending on the dose (from 10 to 200 μg/mL), it was found that both plant extracts did not show a genotoxic effect at the highest concentration of 200 μg/mL. Indeed, data amassed from this current scientific work showed the two selected Astragalus species to be rich in bioactive polyphenols that could be responsible for the various pharmacological activities and hence demands to be further explored for their possible applications as natural health promoting agents.

Astragalus species: Insights on its chemical composition toward pharmacological applications

Astragalus L. is widely distributed throughout the temperate regions of Europe, Asia, and North America. The genus is widely used in folk medicine and in dietary supplements, as well as in cosmetics, teas, coffee, vegetable gums, and as forage for animals. The major phytoconstituents of Astragalus species with beneficial properties are saponins, flavonoids, and polysaccharides. Astragalus extracts and their isolated components exhibited promising in vitro and in vivo biological activities, including antiaging, antiinfective, cytoprotective, antiinflammatory, antioxidant, antitumor, antidiabesity, and immune-enhancing properties. Considering their proven therapeutic potential, the aim of this work is to give a comprehensive summary of the Astragalus spp. and their active components, in an attempt to provide new insight for further clinical development of these xenobiotics. This is the first review that briefly describes their ethnopharmacology, composition, biological, and toxicological properties.

Antioxidant and antimicrobial activities of four Astragalus species growing wild in Turkey

Objective

The objective of the present study was to investigate the phenolic compositions, antioxidant, antimicrobial and cytotoxic activities of four Astragalus species, two of which are endemic to Turkish flora.

Methods

The total phenolic and flavonoid contents of methanol extracts obtained from four Astragalus species were detected using Folin-Ciocalteu and aluminum chloride colorimetric assays. Their phenolic compositions were identified by Liquid chromatography–mass spectrometry (LC-MS). The antioxidant activity was assayed with phosphomolybdenum, 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH), hydrogen peroxide scavenging, β-carotene bleaching activity, ferric-ion reducing power (FRAP) and cupric ions (Cu2+) reducing antioxidant capacity (CUPRAC) methods. Antimicrobial activities of the extracts were studied by agar well-diffusion assay. The cytotoxic effects of the extracts on MCF-7 (human breast cancer cell lines) were determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide) method.

Results

The extracts exerted moderate antioxidant and reducing activity with low phenolic contents. The main component in the extracts was determined as ferulic acid. The extracts demonstrated no antibacterial activity except P. aeruginosa. A. talasseus showed the highest cytotoxic activity on MCF-7 during 48 h.

Conclusion

It is believed that the results of this study will contribute to research recently increasing for the use of natural antioxidant and antimicrobial compounds in many industrial fields such as food, pharmacy and medicine.

Antioxidant activity and Hypolipidemic effect of Ficus carica leaf and twig extracts in Triton WR-1339-induced hyperlipidemic mice

BACKGROUND/AIM: The hypolipidemic potential of both leaf and twig extracts of Ficus carica on experimental hyperlipidaemia induced by Triton WR-1339, in Swiss albino mice was investigated. In addition, the phenolic, flavonoid and anthocyanin contents of these extracts and their antioxidant activities were determined. These properties may have a synergistic effect on hyperlipidaemia. MATERIALS AND METHODS: Leaf and twig samples of F. carica were harvested and collected. The study of antioxidant activity of phenolic compounds was determined by the radical DPPH*, ABTS*+ and FRAP assays. The experimental design was carried out using acute oral toxicity study and Triton model hyperlipidaemia on Swiss albino adult male mice. The animals were observed continuously during the 14 days of the study for any physical signs of toxicity. On the 15th day, the animals were sacrificed by decapitation under anesthesia and the organs were observed for macroscopic pathological lesions. Hyperlipidaemia was induced in the mice by a single intravenous (iv) injection of Triton WR 1339 (300 mg/kg body weight), and the antihyperlipidemic effect of each extract, studied at 150 and 300 mg, was tested by gavage. After 24 hours of administration, serum from blood samples was used to estimate the various parameters of the lipid profile namely TC, TG, LDL and HDL. RESULTS: The results of the phenolic and flavonoid compounds of Ficus carica leaves and twigs varied from 12.84 to 19.78 mg gallic acid equivalents (GAE) and 5.02 to 9.72 mg EQ/g dry matter, respectively. The scavenging activity (IC50) against the radical DPPH* and ABTS*+ varied from 346.2 to 461.38 μg/mL and 288.3 to 369.01 μg/mL for twigs and leaves respectively, and from 50.82 to 54.2 μg/mL for FRAP assay. The acute toxicity study showed no mortality and clinical signs of toxicity in the tested doses. The LD50 value of extracts of twigs and leaves of Ficus carica is greater than 5000 mg/kg. The results revealed that the administration of Ficus carica (FC) leaf and twig extracts resulted in a significant (p < 0.05) decline in levels of serum triglycerides, total cholesterol, LDL-c, and VLDL-c, while the serum high-density lipoprotein cholesterol was significantly increased. The decrease rate of the lipid parameters differs significantly (p < 0.05) from the leaf and twig extracts and depends also on the administered dose. CONCLUSION: Ficus carica leaf and twig extracts may contain compounds able to lower plasma lipid concentrations, could contribute significantly to the total antioxidant properties and be beneficial in the treatment of hyperlipidaemia.

Extraction condition optimization and effects of drying methods on physicochemical properties and antioxidant activities of polysaccharides from Astragalus cicer L

Response surface methodology (RSM) including three variables was performed to optimize the extraction parameters of Astragalus cicer L. polysaccharides (ACPs). The influence of different drying techniques on the physicochemical properties and antioxidant abilities of ACPs were evaluated. The ACPs were dried with hot air (HD), vacuum (VD) and freeze drying (FD) methods. The optimal conditions for ACPs extraction were as follows: water to raw material ratio of 25 mL/g, extraction time of 61 min and temperature of 75 °C. Under these parameters, an ACPs yield of 10.97% was obtained. HPLC analysis showed that the monosaccharide compositions of the three ACPs dried with HD, VD or FD techniques were identical. The three ACPs exhibited antioxidant abilities in a concentration-dependent manner. ACPs dried with the FD method (FD-ACPs) had the best antioxidant activities, which might be related to their smaller molecular weight and higher uronic acid content. At the determined concentration of 1 mg/mL, the ferric reducing power, and DPPH and ABTS free radical scavenging capacities of FD-ACPs were 0.762, 75.30% and 99.21%, respectively. Therefore, FD was a good choice for the drying of Astragalus cicer L. polysaccharides.

Impact of Ohmic-Assisted Decoction on Bioactive Components Extracted from Yacon (Smallanthus sonchifolius Poepp.) Leaves: Comparison with Conventional Decoction

Yacon (Smallanthus sonchifolius Poepp.) leaves are a potentially rich source of bioactive compounds, such as phenolic acids and flavonoids. In this study, the effect of the extraction method (ohmic-assisted decoction (OH-DE) and decoction (DE)), yacon cultivar (red and white), and leaf age (young and old) on the quality/quantity of extracted phytochemicals were investigated. Extraction yield, energy consumption, total phenolic content (TPC), total flavonoid content (TFC), ABTS and DPPH radical scavenging activity, and ferric reducing antioxidant power (FRAP) were determined. Additionally, HPLC-DAD was used to identify the major individual phenolic and flavonoid compounds of yacon leaves. The results showed that a three-way interaction of process-variables (extraction method×yacon cultivar×age of leaves) influenced the extraction yield, TPC, TFC, ABTS, and DPPH radical scavenging activity, and FRAP, significantly (p < 0.05). However, energy consumption of the extraction process was only affected by method of extraction (p < 0.05) and was halved when OH-DE was applied as compared to DE alone. Additionally, the phytochemical quality of extracts was either improved or comparable when OH-DE was used for extraction. Also, it was shown that yacon leaves contained considerable amounts of caffeic acid, chlorogenic acid, ferrulic acid, myricetin, p-coumaric acid, and rutin, while leaves of the red cultivar had higher contents of each compound compared to leaves of the white cultivar.