Phytoecdysteroid C2-hydroxylase is microsomal in spinach, Spinacia oleracea L

Phytoecdisteroids from Serratula coronata when growing ducklings

This article presents the results of comprehensive studies to analyze the effect of a mixture of phytoecdysteroids extracted from the juice of Serratula coronata L. on the productivity and vitality of ducklings when grown for meat, and the optimal doses of its inclusion in the diet of the bird are revealed. The methodological basis of this study was the earlier works of domestic and foreign scientists on the topic under study. In the studies, a mixture of ecdysteroids extracted from the juice of the Serratula coronata L. was used according to the method developed by a team of scientists of the Ufa Federal Research Center of the Russian Academy of Sciences (Patent RU 2151598). The object of the study was the young ducks of the cross breed "Agidel 34" of the Beijing breed. It was established that the use of phytoecdysteroids in the diets of ducklings at a dose of 1.0 mg/l of drinking water allowed to increase the safety of the livestock by 4.0%, live weight by 4.5% (p <  0.01), average daily live weight gain by 3.0-3.5%, gutted carcass weight - 7.1%. At the same time, feed costs per unit of production decreased by 2.0%, and the profitability of duck meat production increased by 5.2%.

Functional characterization of CYP71D443, a cytochrome P450 catalyzing C-22 hydroxylation in the 20-hydroxyecdysone biosynthesis of Ajuga hairy roots

20-Hydroxyecdysone (20HE), a molting hormone of insects, is also distributed among a variety of plant families. 20HE is thought to play a role in protecting plants from insect herbivores. In insects, biosynthesis of 20HE from cholesterol proceeds via 7-dehydrocholesterol and 3β,14α-dihydroxy-5β-cholest-7-en-6-one (5β-ketodiol), the latter being converted to 20HE through sequential hydroxylation catalyzed by four P450 enzymes, which have been cloned and identified. In contrast, little is known about plant 20HE biosynthesis, and no biosynthetic 20HE gene has been reported thus far. We recently proposed involvement of 3β-hydroxy-5β-cholestan-6-one (5β-ketone) in 20HE biosynthesis in the hairy roots of Ajuga reptans var. atropurpurea (Lamiaceae). In this study, an Ajuga EST library was generated from the hairy roots and P450 genes were deduced from the library. Five genes with a high expression level (CYP71D443, CYP76AH19, CYP76AH20, CYP76AH21 and CYP716D27) were screened for a possible involvement in 20HE biosynthesis. As a result, CYP71D443 was shown to have C-22 hydroxylation activity for the 5β-ketone substrate using a yeast expression system. The hydroxylated product, 22-hydroxy-5β-ketone, had a 22R configuration in agreement with that of 20HE. Furthermore, labeling experiments indicated that (22R)-22-hydroxy-5β-ketone was converted to 20HE in Ajuga hairy roots. Based on the present results, a possible 20HE biosynthetic pathway in Ajuga plants involved CYP71D443 is proposed.

Into the world of steroids: a biochemical "keep in touch" in plants and animals

Evolution of steroids such as sex hormones and ecdysteroids occurred independently in animal and plant kingdoms. Plants use phytoecdysteroids (PEs) to control defence interactions with some predators; furthermore, PEs can exert beneficial influence on many aspects of mammalian metabolism. Endocrine disrupting compounds such as the estrogen agonist bisphenol A (BPA) are widespread in the environment, posing a potential hormonal risk to animals and plants. Adverse BPA effects on reproductive development and function are coupled with other toxic effects. BPA bioremediation techniques could be developed by exploiting some tolerant plant species.