Accession Number:

AD0442324

Title:

STEROIDS AND THE STIMULATION OF SEXUAL REPRODUCTION OF A SPECIES OF PYTHIUM,

Descriptive Note:

Corporate Author:

NATIONAL RESEARCH COUNCIL OF CANADA SASKATOON (SASKATCHEWAN) PRAIRIE REGIONAL LAB

Personal Author(s):

• Haskins,R. H.
• Tulloch,A. P.
• Micetich,R. G.

Report Date:

1963-12-24

Pagination or Media Count:

9.0

Abstract:

The fatty acid compositions of the mycelia of a parasitic species of Pythium and of various hosts are reported. The Pythium spp. contained high concentrations of myristic acid and low concentrations of myristic acid and low concentrations of linoleic and linolenic acids in comparison with concentrations in other fungi tested. Appreciably amounts of unsaturated C20 acids, uncommon in fungi, were found in the Phycomycetes tested. Vegetable oils and other fats of widely varying fatty acid compositions were all effective in stimulating sexual reproduction of the Pythium sp. It was concluded that substances other than fatty acids present in the vegetable oils were responsible for the stimulation observed. The most active fraction in sunflower seed oil was isolated and identified as a phytosterol, probably beta-sitosterol. The results of testing for stimulatory activity a series of structurally related compounds indicated that the sexual reproduction of the Pythium sp. studied required the presence of a substance such as beta-sitosterol or cholesterol or one with similar structure and with similarly satisfied certain specific structural requirements regarding length of the C17 side chain, stereochemistry, and position of the oxygenated function. Beta-sitosterol and cholesterol were effective at 0.2 gammaml in potato dextrose agar. Author

Descriptors:

• STEROIDS
• BIOCHEMISTRY
• FUNGI
• STIMULATION(PHYSIOLOGY)
• REPRODUCTION(PHYSIOLOGY)
• FATTY ACIDS
• BIOSYNTHESIS
• TISSUE EXTRACTS
• PLANTS(BOTANY)
• STEREOCHEMISTRY

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE