The health benefits of green and black tea are mainly associated with their antioxidant potential and phenolic compounds. The present study aimed to evaluate the effects of dried rose petals (Rosa damascena) on the antioxidant capacity of green and black tea. Antioxidant capacities of tea and rose infusions were assessed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2-azinobis-3-<...

A series of 3,4-dihydroisoquinoline-3-carboxylic acid derivatives were synthesised and tested for their free-radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS·+), superoxide anion radical (O2·-) and nitric oxide radical (·NO) assays. We also studied d-amino acid oxidase (DAAO), acetylcholinestera...

Emission regulations for small utility, lawn, and garden equipment engines went into effect in 1995 in the U.S. Tier 2 standards of the California Air Resource Board (CARB) went into effect in 2000. Reducing emission of small two-stroke cycle engines is thought to be difficult due to incomplete scavenging. Two-stroke cycle engines have many features favoring handheld equipment, so we studied ne...

The effect of removal of resultant gas resulted in enhancement of the H2 yield. The technique of CO2 scavenging resulted in H2 yield being improved from 408 mL g(-1) to reach the maximum of 422 mL g'. The highest hydrogen productivity of 87.9 ml L(-1) h(-1) was obtained by CO2 scavenging. Biomass concentration was enhanced to 1.47 g L(-1), Y(P,X) of 287 ml g(-1) L(-1), Y(X/S) of 0.294 and Y(H2/...

Rice straw was separated into four parts: the upper, middle, and lower parts of the stem, and the leaf. They were treated with subcritical water at 140 to 260 °C. The yield, carbohydrate, protein, and phenolic contents were obtained as well as the UV-Vis absorption spectra and the radical scavenging activity of the extracts. The extracts obtained from the stem parts had almost the same characte...

In this study, sulfated low molecular-weight Tremella fuciformis polysaccharides (SLTP) with different sulfate contents were synthesized and their antioxidant activities, including superoxide anion radical, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical and hydroxyl radical scavenging activities were investigated. The results indicated that, compared to natural Tremella fuciformis polysaccharide...

The antioxidant activity of naturally occurring stilbene compounds piceatannol (PIC) and isorhapontigenin (ISO) scavenging two free radicals (NO and NO2) were studied using density functional theory (DFT) method. Four reaction mechanisms have been considered: hydrogen atom transfer (HAT), radical adduct formation (RAF), single electron transfer (SET), and sequential proton loss electron transfe...

To evaluate the free radical scavenging activity of flavonoids containing extracts of Stevia leaf. Alcoholic. Successive butanolic and alcoholic extracts of leaves were examined for free radical scavenging activity using BHT (tert-butylhydroxytolune) as a positive control by in vitro models. Successive alcoholic extract showed remarkable free radical scavenging activity. The IC(50) was found to...

In the present study, coarse powder of Scindapsus officinalis (Roxb.) Schott. fruit was extracted successively using hexane, chloroform, ethyl acetate and 50% ethanol. The ethyl acetate and 50% ethanolic extracts were investigated for its antioxidant activity by using nitric oxide and DPPH radical scavenging methods. The IC value was also calculated. Ascorbic acid was used as standard. Both the...