Comparative Study on Phenolic Compounds and Antioxidant Activities of Hop (Humulus lupulus L.) Strobile Extracts

In this study, we investigated the phenolic compounds in hop strobile extracts and evaluated their antioxidant property using DPPH and ABTS assay. The total phenolic compound (TPC) and total flavonoid compound (TFC) estimated in two different solvent extracts considerably varied depending on the extraction solvent. The most abundant phenolic compound in hop strobile was humulones (α-acid) with levels ranging from 50.44 to 193.25 µg/g. El Dorado accession revealed higher antioxidant activity in ethanol extracts (DPPH: IC50 124.3 µg/mL; ABTS: IC50 95.4 µg/mL) when compared with that of the other accessions. Correlations between DPPH (IC50) scavenging TFC in ethanol extract (TFC_E, −0.941), and TPC_E (−0.901), and between ABTS (IC50) scavenging TFC_E (−0.853), and TPC_E (−0.826), were statistically significant at p < 0.01 level, whereas no significant correlation was observed between antioxidant activities, TPC and TFC in water extract. This study is the first to report that variations in the level of phenolic contents and antioxidant activity of various hop cultivars depended on the type of extraction solvent used and the cultivation regions. These results could provide valuable information on developing hop products.

In vitro antioxidant, antiglycation, and MGO scavenging effects of Leonurus sibiricus water extract

Recently, extensive research has been conducted to evaluate the inhibitory activity of different plant species on the advanced glycation end products (AGEs). L. sibiricus is a traditional herb that has been used for postpartum confinement meals in Sarawak, Malaysia and pharmacologically possess anti-hemorrhagic, antioxidant, anti-diabetic, and anti-cancer. The aim of this research was to evaluate the antioxidant, anti-AGEs, and preliminary biochemical screening of bioactive component present in L. sibiricus in water extract. Free radical scavenging activity of L. sibiricus was evaluated via DPPH, hydroxyl radical, nitric oxide, lipid peroxidation, chelating capacity, and total phenolic content was evaluated comparing with gallic acid. Inhibition of formation AGEs by L. sibiricus was evaluated using BSA-MGO, BSA-glucose and MGO scavenging assays. Flavonoids, phenols, saponins, alkaloids, phytosterol, and diterpenoids were identified in L. sibiricus extract. It also seems to inhibit early and late formation of AGE and MGO scavenging ability. L. sibiricus was able to inhibit the formation of early and late formation of AGE through the scavenging of the formation of reactive dicarbonyl intermediates and reduce the formation of methylquinoxaline adducts through the scavenge of MGO. The inhibition of AGEs formation by L. sibiricus maybe due its antioxidant property and the presence phytochemical bioactive constituents which has been previously reported to possess antioxidant and anti-AGE activity. Future research is ongoing to identify the adducts formed because of MGO scavenging by L. sibiricus using HPLC.

Evaluation Of In Vitro Antioxidant, Phytochemical and Gc-Ms Analysis of Aqueous Extract of Solanum Dasyphyllum Fruits

Phytochemicals, antioxidant and the bioactive compounds present in the fruits of Solanum dasyphullum was investigated. Several phytochemicals such as saponins, tannins, alkaloids, flavonoids, steroids and cardiac glycosides were detected. A total of 172 compounds were identified by GC-MS. Phenols, spermine, 2, 5- dimethylfuran and 2-methyl-1-hexadecanol were all identified. These compounds are known to have antioxidant property which may be responsible for the antioxidant property of the fruit extract. It was observed that the fruits extract exhibit antioxidant properties. The scavenging activity increases with the concentration of the extract with the following percentage scavenging activity; 200µg(90%),133µg (78%), 100 µg(69%), 67 µg(48), 33 µg(26.7%), 20 µg(18), 7 µg(7%). Compounds identified in the fruits of Solanum dasyphylum can be isolated and used as an antioxidant. Keywords: Solanum dasyphylum, oxidation, antioxidant and extracts.

Phytochemical analysis and investigation of Antimicrobial and Antioxidant potential of the Leaf Extracts of Putranjiva ruxburghi

Objectives: Herbs are in use as medicine worldwide from the time immemorial. Many drugs derived from plant, animal or minerals are in use as medicine till date. This is a study on leaf extract of Putranjiva roxburghii Wall. (Euphorbiaceae) involving pharmacognosy, phytochemistry, activity against microbes and oxidation to substantiate its use. The leaf extracts were collected by successive soxhlation using solvents like petroleum ether, chloroform, benzene, acetone & ethanol. Chemicals present in the crude leaf extracts and isolated constituents were analyzed for both quality and quantity followed by TLC, UV–Visible Spectrophotometric analysis, HPTLC, Phytochemical tests and TLC examination confirmed to contain flavonoids in acetone, chloroform, aqueous and ethanol extract. The activity of Petroleum-ether, chloroform, acetone, alcoholic and aqueous extracts against the microbes was assessed by cup plate method. Okada & Okada method was followed to evaluate the DPPH free radical for aging property. The reducing, total antioxidant and peroxide radical for aging action of the extracts were assessed. The study confirmed significant antimicrobial and antioxidant property of the Putranjiva roxburghii Wall leaves may be for the presence of constituents like flavonoids, saponins, Phytosterols, favoring its traditional usage as medicine.

In vitro Antioxidant activity and Phytochemical composition of Syringodium isoetifolium

Seagrass are the marine flowering plants found mainly in clear, shallow estuaries and coastal waters. In all temperate and trophical region seagrasses grow both internally and subtidally. One such seagrass namely Syringodium isoetifolium has many medicinal properities. This seagrass have most promising pharmacological activities which may include anti-inflammatory, anticancer, antidiarrheal, antihaemorrhoidal activities. This study is focussed on the phytochemical evaluation and in vitro antioxidant activity of aqueous, ethanol and hydroalcoholic extract of Syringodium isoetifolium. The qualitative analysis of Syringodium isoetifolium shows the presence of tannin, saponin, flavonoids, steroids, terpenoids, alkaloids, anthraquinone, polyphenol and coumarin. In all the three extracts only ethanol shows the high concentration of phytocompounds. Emodins, glycoside and anthocyanin were found to be absent in all the three extracts. Quantitative analysis of total phenol, flavonoid, saponin and tannin were found to be 193.10 ±13.52, 106.11 ± 7.42, 52.96 ± 3.64 and 81.30 ± 5.69. Superoxide anion radical, Nitric oxide and Hydroxy radical scavenging assay showed that Syringodium isoetifolium was an excellent scavenger of these radicals. These results are an indication of the potent antioxidant property of the extract and may be responsible for some of the therapeutic uses of Syringodium isoetifolium.