1-Octen-3-ol and 10-oxo-trans-8-decenoic acid in the cultivated mushroom, Agaricus bisporus.
Mau, Jeng-Leun.
Thesis (Ph.D.), Pennsylvania State University. Pennsylvania State, USA. 1992. 148 p.
1992
บทคัดย่อ
1-Octen-3-ol and 10-oxo-trans-8-decenoic acid (ODA) are formed from linoleic acid by lipoxygenase and hydroperoxide lyase when mushroom tissue is damaged. This research was designed to study 1-octen-3-ol formation in mushrooms, Agaricus bisporus (Lange) Imbach. Techniques for the preparation and isolation of ODA were developed, and its physiological effects on mushrooms, Agaricus bisporus, examined.
1-Octen-3-ol formation as a function of pH and during postharvest storage at 3, 12 and 25circC were investigated. The potential for 1-octen-3-ol formation at different stages of maturity and in different tissues were also investigated. 1-Octen-3-ol content of mushrooms was not affected by supplementing nutrients high in linoleic acid to compost. Adding calcium chloride to irrigation water to improve quality and shelf life of mushrooms increased the 1-octen-3-ol content.
To study its effects on mushrooms, a procedure was developed to prepare and isolate ODA. ODA was produced by homogenizing mushrooms in buffer with linoleic acid, extracted from the supernatant after centrifugation, and purified using column chromatography and thin-layer chromatography. The purified compound was characterized using ultraviolet, infrared, mass spectrometry and nuclear magnetic resonance spectroscopy. The purified compound containing 97.5% ODA was a white, waxy solid with a pKa of 4.68.
Purified ODA was used to study its effects on mycelial growth and on the elongation of mushroom stipes. The effect of ODA on mushroom production was studied by supplementing a crop with ODA in the form of mushroom powders. Its antimicrobial effect on bacteria and yeasts was also examined.
The linear mycelial growth rate on agar was greatly increased by ODA at 18.4 and 36.8 ppm. Mycelial growth in broth was stimulated by ODA at 0.184 and 1.84 ppm. After 5 weeks, mycelial dry matter was greater at ODA concentrations of 0.184 and 1.84 ppm. Upper stipe elongation was promoted by the application of supernatants containing ODA to agar plates. Adding ODA to agar in contact with stipes affected the elongation of upper stipe only when lower stipes were present. Since ODA was stimulatory to mycelial growth and stipe elongation, it is considered a mushroom hormone.