Precocene II, a constituent of essential oils, shows antijuvenile hormone activity in insects and inhibits trichothecene production in fungi. We investigated the molecular mechanism by which precocene II inhibits trichothecene production in Fusarium graminearum, the main causal agent of Fusarium head blight and trichothecene contamination in grains. Voltage-dependent anion channel (VDAC), a mit...

Precocene Analogues, Deuteration A convenient route for the preparation of title compounds from benzopyran-4-one (1) and its corresponding 3,3-H2 deuterated analogue (2) is reported. Treatment of 1 or 2 with lithium aluminum deuteride followed by dehydration afforded, respectively, 4-H precocene (3c) or 3,4-H2 precocene (3b). Likewise, reduction of 2 with lithium aluminum hydride and subsequent...

Precocene II, Anti-Juvenile Hormone, Honey Bee, Apis mellifera, Anti-Feedant The effect of precocene II on development of the honey bee, Apis mellifera, was studied in vitro. Oneto two-day-old worker larvae (body weight 0.5 — 1.0 mg) were removed from the colonies, reared on royal jelly-yeast extract, and after 24 h were topically applied with different amounts (5 75 |ig/larva) of precocene II....

Administration of precocene II (6,7-dimethoxy-2, 2-dimethyl chromene) to freshly emerged virgin female flies of S. ruficornis adversely affected the development and differentiation of ovarian follicles leading to a number of morphological abnormalities. Precocene treatment resulted into suppression of development of egg chamber, differentiation of follicular epithelium, degeneration of nurse ce...

Treatment of early and late third instar larvae of economically important insect C. megacephala with the ageratochromene precocene II resulted into precocious metamorphosis. The other effects included mortality, production of pupal-adult mosaics, reduction in percentage of adult emergence and formation of non-viable deformed adults that died after a few hours of emergence. The application of pr...

The correlation of ATP citrate lyase (ACL) and acetyl CoA levels with trichothecene production in Fusarium graminearum was investigated using an inhibitor (precocene II) and an enhancer (cobalt chloride) of trichothecene production by changing carbon sources in liquid medium. When precocene II (30 µM) was added to inhibit trichothecene production in a trichothecene high-production medium contai...

Analysis of extracts of hemolymph obtained from sexually mature alate females of Solenopsis invicta from monogyne colonies resulted in identification of juvenile hormone III (JH III). The average amount of JH III was 0.32+/-0.04 pmol/&mgr;molof hemolymph. Topical application of 0.038 pmol of JH III was sufficient to stimulate alates to shed their wings in the presence of the queen. The time in ...

Juvenile hormone (JH) is an important regulator of development and physiology in insects. While in many insect species, including bumble bees, JH functions as gonadotropin in adults, in some highly eusocial insects its role has shifted to regulate social behavior including division of labor, dominance and aggression. Studying JH functions across social insect species is important for understand...

Aflatoxins are highly toxic and carcinogenic metabolites produced by Aspergillus parasiticus on food and agricultural commodities. Natural products may control the production of aflatoxins. The aims of this study were to evaluate the Inhibition of Aspergillus flavus (La3228) and A. parasiticus (Ab2242) growth and their aflatoxin production exposed to the essential oil extracted from fresh leave...