Tea catechins, an important class of polyphenols, have been shown to have wide spectrum of antitumor activity believed to be due mainly to their antioxidative effect. In this study, the radical scavenging behavior of catechins on 2,2-diphenyl-1-picrylhydrazyl (DPPH) was studied. Two reaction products of (+)-catechin, and two reaction products of (-)-epicatechin were purified and identified. The...

In this study, ethanol extracts from 2-day fermented black soybean milk (FBE) by immobilized Rhizopus oligosporus NTU5 have been evaluated for both antioxidant and cytotoxic activities. The results reveal that a 2-day FBE had strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging effect (76 %). The extracts were further fractionated by silica gel column chromatography and an unknown compound, F...

Five geranylflavonoids, one prenylated flavonoid, and a simple flavanone were isolated from an ethanolic extract of Paulownia tomentosa fruit. Tomentodiplacol (1), 3'-O-methyl-5'-methoxydiplacol (2), 6-isopentenyl-3'-O-methyltaxifolin (3), and dihydrotricin (4) are reported from a natural source for the first time and 3'-O-methyldiplacone (6) for the first time from the genus Paulownia. The str...

The essential oil of locally available Trachyspermumammi(ajowan) seeds was obtained through hydrodistillation. Its chemical composition analysed by gas chromatography mass spectrometry (GC-MS). Twenty - two compounds EO were identified with the help NIST library. Thymol (38.5%), ρ-cymene (27.2%) and γ-terpinene (26.8%) as major components. Furthermore, its antioxidant power IC50 value 65.3 μ...

A new butenolide derivative (1), along with three known compounds (2-4) were isolated from the MeOH extract of brown alga Sargassum micracanthum. The structures 1 to 4 determined by analyses 1D and 2D NMR mass spectroscopic data. identified as (5 E,10 Z)-6,10,14-trimethylpentadeca-5,10-dien-2,12-dione (2), E,9 E)-6,10,14-trimethylpentadeca-5,9-dien-2,12-dione (3), (-)-loliolide (4) comparing th...

Fifteen phenolic compounds, including three caffeoyl derivatives, four gallotannins, three ellagitannins and five flavonoids, were isolated from an 80% MeOH extract of the leaves of Corylopsis coreana Uyeki (Korean winter hazel; CL). The anti-oxidative activities [1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and xanthine oxidase superoxide scavenging activities (NBT)] and th...

The carotenoids produced by extremely halophilic archaeon Haloarcula japonica were extracted and identified by their chemical, chromatographic, and spectroscopic characteristics (UV-Vis and mass spectrometry). The composition (mol%) was 68.1% bacterioruberin, 22.5% monoanhydrobacterioruberin, 9.3% bisanhydrobacterioruberin, <0.1% isopentenyldehydrorhodopin, and trace amounts of lycopene and phy...

In the present study, antioxidant potential of the different extract of the whole plant of Aerva tomentosa Forsk. was evaluated by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay and total phenolic contents was analyzed using the Folin-Ciocalteu reagent method. The methanol extract showed significant activity in antioxidant assay compared to other successive extracts such as peteth...

2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay and nitroprusside assay were used for in vitro study of antiradical/scavenger activity of Philadelphus coronarius petal substances. The results obtained can be used as the basis for further studies of this type of the biological effects in the plant.

The objective of this work is to establish the structural requirements of flavonoids for appreciable radical-scavenging activity (RSA) and elucidate a comprehensive mechanism that can explain their activity. To this end, the RSA of 52 flavonoids against 2,2-diphenyl-1-picrylhydrazyl was determined. The relative change in energy (DeltaH(f)) associated with the formation of various flavonoidal an...