Profiling and characterization antioxidant activities in Anoectochilus formosanus hayata

Phytochemical characteristics and antioxidant activities of the crude and fractionated plant extracts of Anoectochilus formosanus were evaluated using five different assay systems. An acid-treatment (2 N HCl in 95% ethanol) was employed to treat a butanol fraction (BuOH), creating an acid-hydrolyzed BuOH fraction. The IC(50) values for DPPH radicals in the BuOH and acid-hydrolyzed BuOH fractions were 0.521 and 0.021 mg/mL, respectively. The acid-hydrolyzed BuOH exhibited approximately 5-fold higher activity in scavenging superoxide anion than catechin. The acid-hydrolyzed BuOH fraction also effectively protected phi x174 supercoiled DNA against strand cleavage induced by H(2)O(2) and reduced oxidative stress in HL-60 cells. Metabolite profiling showed that the aglycones of flavonoid glycosides in BuOH were produced after acid hydrolytic treatment, and this resulted in a significant increase in antioxidant activities of acid-hydrolyzed BuOH. One new diarylpentanoid, kinsenone, and three known flavonoid glycosides and their derivatives were identified for the first time from A. formosanus, with strong antioxidant properties.     

Bioguided fractionation and isolation of free radical scavenging components from in vitro propagated chinese medicinal plants Dendrobium tosaense Makino and Dendrobium moniliforme SW

This study was performed to investigate the free radical scavenging active components from in vitro propagated medicinal herbs of the genus Dendrobium, namely, Dendrobium tosaense Makino and Dendrobium moniliforme SW, using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical antioxidative assay. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half-strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by reculturing on full-strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose, and 0.9% Difco agar. Healthy plantlets transferred to plastic trays containing moss or moss and tree fern successfully acclimatized (84-100%) in the greenhouse. Extracts were prepared from plants grown in the greenhouse for a period of 6 months. Methanolic extracts of D. tosaense and D. moniliforme scavenged DPPH at 95.9 and 83.4%, respectively, at a concentration of 0.4 mg/mL. Therefore, methanolic solubles of D. tosaense and D. moniliforme were subjected to bioguided fractionation and separation by column chromatographic methods individually. After chromatographic separation of these crude extracts, the obtained fractions (Dm 1, Dm 2, Dm 3, Dt 1, Dt 2, and Dt 3) were tested for their activity. Among them, fractions Dm 2 and Dt 1 showed significant antioxidant activity by DPPH radical antioxidative assay. Active fractions were purified further by column chromatography and resulted in identification of the antioxidant components alkyl ferulates from D. moniliforme and quercetin from D. tosaense.     

Indoor Spawning and Egg Development of the Red Claw Crayfish Cherax quadricarinatus

In 1991 and 1992, indoor hatchery experiments were conducted with red claw crayfish Cherax quadricarinatus a large tropical crayfish from northern Australia. Six fiberglass tanks were stocked with 40–190 g mature red claw crayfish at 10/m² and a 1:2 male to female ratio. Water temperature was maintained at 28 ± 1 C. Photoperiod was provided by natural daylight in 1991 and controlled lighting in 1992.
With natural lighting, monthly spawning rates (% of females spawning/month) ranged from an average of 15% during months with less than 12 h of light per day to over 35% in months with more than 12 h of light per day. Peak spawning occurred from May to July, too late to obtain juveniles for spring stocking. During the second year, photoperiod was increased from 10L:14D in December to 14L:10D in February and maintained at this level until July. Red claw spawning increased with increasing day length. Peak spawning rates of 50% per month and higher occurred from March to May. Spawning rates decreased dramatically after May, even though photoperiod and temperature remained constant. Eggs per spawn increased with an increase in female size. Fecundity average 7.3 juveniles per gram of body weight for females from 40 to 190 g, regardless of size. Egg color was useful for predicting stage of development.