Coinhibitory Effects of Resveratrol- and Protopanaxadiol-Enriched Rice Seed Extracts Against Melanogenic Activities in Melan-a Cells.

In the current study, we aimed to evaluate the combined antimelanogenic effects of resveratrol- and protopanaxadiol (PPD)-enriched rice seed extracts (DJ526 and DJ-PPD) in melan-a cells. The treatment antioxidant capacity was evaluated using the ABTS radical scavenging method. TR_3 (70% [wight ()/] of DJ526 and 30% [/] of DJ-PPD) markedly increased the antioxidant activity at a level similar to that of DJ526 and DJ-PPD alone.

A point mutation of valine-311 to methionine in Bacillus subtilis protoporphyrinogen oxidase does not greatly increase resistance to the diphenyl ether herbicide oxyfluorfen.

In an effort to asses the effect of Val311Met point mutation of Bacillus subtilis protoporphyrinogen oxidase on the resistance to diphenyl ether herbicides, a Val311Met point mutant of B. subtilis protoporphyrinogen oxidase was prepared, heterologously expressed in Escherichia coli, and the purified recombinant Val311Met mutant protoporphyrinogen oxidase was kinetically characterized. The mutant protoporphyrinogen oxidase showed very similar kinetic patterns to wild type protoporphyrinogen oxidase, with slightly decreased activity dependent on pH and the concentrations of NaCl, Tween 20, and imidazole.