Let S-Set be the category of $S$-sets, sets together with the actions of a semigroup $S$ on them. And, let S-Pos be the category of $S$-posets, posets together with the actions compatible with the orders on them. In this paper we show that the category S-Pos is a radical extension of S-Set; that is there is a radical on the category S-Pos, the order desolator radical, whose torsion-free class i...

We have developed a method to determine serum scavenging-capacity profile against multiple free radical species, namely hydroxyl radical, superoxide radical, alkoxyl radical, alkylperoxyl radical, alkyl radical, and singlet oxygen. This method was applied to a cohort of chronic kidney disease patients. Each free radical species was produced with a common experimental procedure; i.e., uv/visible...

Chitosan (CS) is an abundant and renewable polysaccharide that is reported to exhibit a great variety of beneficial properties. However, the poor solubility of chitosan in water limits its applications. In this paper, we successfully synthesized single N-quaternized (QCS) and double N-diquaternized (DQCS) chitosan derivatives, and the resulting quaternized materials were water-soluble. The degr...

The total flavonoids of Houttuynia cordata are determined by UV-Vis spectrophotometry. The extraction condition of flavonoids from Houttuynia cordata includes: the extraction temperature is 70 ̊C, solid-liquid ratio is 1:20, solvent is 80% ethanol, extraction time is 65 min. We studied the antioxidation of flavonoids in Houttuynia cordata, and results showed that flavonoids had strong reducing c...

glucose-6-phosphate dehydrogenase (g6pd) deficient subjects are vulnerable to oxidative stress. quercetin, a flavonoids, has been employed as a potent oxygen-free radical scavenger in order to assess the protective effects of quercetin against h2o2-induced oxidative damage in g6pd-deficient and normal human erythrocytes. erythrocytes of g6pd-deficient (n = 10) and normal (n = 10) subjects were ...

this study was designed to examine the in vitro antioxidant activities and total phenolic contents of the methanolic extracts from male inflorescence of salix aegyptiaca l. grown in iran. the methanolic extract (me) and its three fractions including water (wf), butanol (bf) and chloroform (cf) were prepared and then their antioxidant activities, as well as total phenolic contents, were evaluate...

the methanol extracts of leaves of bauhinia acuminata (mesf) and their different fractions obtained from modified kupchan partitioning method i.e. methanol, pet ether, carbon tetrachloride, chloroform, and aqueous soluble fractions were subjected to biological screening such as total phenolic content and antioxidant activity screening.the amount of total phenolic content differed in different e...

The major unexplained phenomenon in fibrotic conditions is an increase in replicating fibroblasts. In this report we present evidence that oxygen free radicals can both stimulate and inhibit proliferation of cultured human fibroblasts, and that fibroblasts themselves release superoxide (O2.-) free radicals. Fibroblasts released O2.- in concentrations which stimulated proliferation, a finding co...

A series of 3-styrylchromone derivatives (4-20) were synthesized and the structure-activity relationships for α-glucosidase inhibition and antioxidant activities were analyzed. Among the synthesized compounds, compounds 15 and 20, which contain a catechol moiety, showed both potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity (15: EC₅₀=17 µM; 20: EC₅₀=23 µM) and α-gluco...