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The methanol extract of Coreopsis lanceolata L. petals was acid-hydrolysed, and 7,3',4'-trihydroxy-8-methoxyflavanone (1) and 6,3',4'-trihydroxy-7-methoxyaurone (leptosidin) (2) were successfully isolated. The structure of compound 1 is designated to flavanone based on X-ray crystallographic analysis and NMR spectroscopic analysis. Compound 1 showed high-antioxidant effects based on diphenylpicrylhydrazyl radical scavenging assay (94.3% scavenging rate) and superoxide dismutase-like activity assay (23.9% inhibition rate).

Fatty acids of Euterpe oleracea Mart seeds were analyzed in hexane and diethyl ether extracts. The hexane extract contained dodecanoic acid (3), tetradecanoic acid (4), hexadecanoic acid (7), and 9-octadecenoic acid (10). The diethyl ether extract contained (10). The oil of Mart seeds was obtained firstly by methanol extract and further extracted with diethyl ether. The hexane and diethyl ether extracts were then analyzed for antioxidant effects. Both extracts demonstrated a 1,1-diphenyl-2-picrylhydrazyl radical elimination effect similar to that of α-tocopherol and an active oxygen inhibition effect. Significant quantities (0.6212 mg/mL) of polyphenol, in comparison to the standard rejected gallic acid, were found in the extract oil of Mart seeds by the methanol extraction.

In this study, we investigated the antioxidant components of three types of colored rice bran--forbidden rice, red rice and green rice--obtained from rice in which the pigment layer had been removed at milling yields of 90%-100% and 80%-90%. An evaluation of the effects of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity revealed that rice bran obtained from forbidden rice at milling yields of 90%-100% and 80%-90% and rice bran obtained from red rice at milling yields of 90%-100% showed favorable antioxidant activity. The antioxidant components were confirmed to be 3,4-dihydroxy methyl benzoate and p-methoxyphenol and they influence the antioxidant activity of the three types of colored rice bran.

Petals from Coreopsis lanceolata L. were extracted in methanol and subjected to solvent-solvent partitioning to yield four fractions: hexane, diethyl ether, ethyl acetate, and aqueous. These fractions were screened using a 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay and an active oxygen inhibition assay. The ethyl acetate extract contained the highest level of active components. Four compounds isolated from this fraction by HPLC were screened for antioxidant activity and anti-allergic activity. Anti-allergic activity was assessed by measuring release of histamine from rat peritoneal mast cells. One compound, termed laceolin, was characterized by spectroscopic analysis, including extensive NMR and mass spectra. This compound had significant radical scavenging activity, with an SC50 (scavenging concentration of 50%) value of 2.6 microg/mL and superoxide dismutase activity of 46.2%.

Physiological activities of four types of phytoncide solutions (A, AB, CY and D-types), prepared from various plants widely distributed in nature, were examined. We assayed these phytoncide solutions, testing for active oxygen inhibition, DPPH radical scavenging effects, nitrogen monoxide inhibition, and lipid peroxide inhibition. The AB- and D-types of phytoncide solutions especially showed comparably potent antioxidant effects. Antibacterial and antifungal assays were conducted using the AB- and D-types, with results showing significant inhibitory activities with these solutions.

The antioxidative activity of phenylpropanoid compound extracts from nutmeg (Myristica fragragrans Houttuyn) seed was determined. The antioxidant activity was evaluated using the 1,1-diphenyl-2-picrylhydrazyl radical-scavenging method, superoxide disumutase assay, ferric thiocyanate assay, and radical-scavenging effect assay with electron-spin resonance. High antioxidant activity was found in monoterpenoid extracts including terpinene-4-ol (3), alpha-terpineol (4), and 4-allyl-2,6-dimethoxyphenol (12). Compound, 12 expressed particularly high antioxidant activity.

Eugenol, isoeugenol, caffeic acid, ferulic acid, isoferulic acid, estragole, trans-anethole, and paeonol are components of a Chinese herbal medicine used as a painkiller and stomachic. We investigated the potential role of these compounds as antioxidants. We studied the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging effect of these molecules, together with some glycoside derivatives, to ascertain their potential in reducing the levels of activated oxygen species in vivo. The DPPH radical-scavenging effects of eugenol, isoeugenol, and the glycoside derivatives of caffeic acid, ferulic acid, and isoferulic acid (SC(50)=8-28 microM) were similar to those of alpha-tocopherol, which was used as a positive control.

The article presents a study on the synthesis of acyl arbutin and its antioxidative effects on methyl linoleate. The study used oil-in-water (O/W) emulsion, hydrophilic and lipophilic antioxidants to elucidate the behavior of acyl arbutin. It states that the synthesis was done by lipase-catalyzed condensation of arbutin with saturated fatty acid. The study showed that the increase in oxidation of methyl linoleate and acyl chain length was caused by the suppressive effect of acyl arbutin.

Abstract: Strawberry impregnated with sucrose was used for the jam preparation, and its effects on the stability of anthocyanins and the jam color were examined. The amount of sucrose in impregnated strawberry depended on the concentration of sucrose solution and the operation time for the impregnation. In comparison with only the addition of sucrose to the jam preparation, the impregnation of strawberry in advance of the jam preparation stabilized anthocyanins in the jam. The antioxidative ability of the strawberry jam correlated with the amount of anthocyanin. Furthermore, the rate constants by the Weibull model for the degradation of anthocyanins and the chromatic deterioration of the jam were estimated, and the relationship between the two rate constants was found to be almost linear. It was shown that the impregnation of strawberry with sucrose was effective for improving functions, such as antioxidative activity and the color of its jam. [ABSTRACT FROM AUTHOR]

Abstract: Three lauroyl phenolic glycosides were synthesized through the condensation of phenolic glycoside such as arbutin, naringin and phloridzin with lauric acid by immobilized lipase in various organic solvents. The conversion depended on the polarity of the organic solvent used for the reaction. The suppressive effect of each lauroyl phenolic glycoside against the oxidation of linoleic acid was higher than that of the corresponding phenolic glycoside, whereas there was no difference between the DPPH radical scavenging activities of unmodified and lauroyl phenolic glycosides. The antioxidative activity of the glycoside was indicated to depend on the number and the placement of phenolic hydroxyl group exhibiting the activity in the molecule. [Copyright &y& Elsevier]