Physiological inhibitory effect of ocs in arachidonic acid-richParietochloris incisa (trebouxiophyceae, chlorophyta)
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Parietochloris incisa is an arachidonic acid-rich snow green alga. The main physiological profiles, such as ash free dry weight (AFDW), chlorophyll, carotenoid, protein and total fatty acids (TFA), in this alga exposed to old culture supernatant (OCS) at the decline phase or its crude ethyl acetate extracts (CEAE) were investigated by using tubular photobioreactors of different diameters. Results showed that both OCS and CEAE had strong inhibitory effect on the above physiological parameters. The longer the culture was exposed to OCS and the more CEAE were added into the algal culture, the more the above physiological properties were inhibited. Arachidonic acid (AA), the dominant component of fatty acids in this alga, was also seriously inhibited with respect to total TFA, AFDW of cell mass, or culture volume, due to a probable reduction of enzymes activities catalyzing chain elongation from C18; 1ω9 to AA. These results incontestably evidenced that some CEAE dissolving substances existing in OCS. like auto-inhibitors, inhibitedP. incisa growth through feedback. Hence, any efficient removal of auto-inhibitors from algal culture to decrease their bioactivity could be good for maximal production of desired products like AA.
Key wordsarachidonic acid Parietochloris incisa growth auto-inhibitor
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- Arnon, D. I., 1949. Copper enzymes in isolated chloroplasts; polyphenol oxidase inBeta vulgaris.Plant Physiol. 24: 1–15.Google Scholar
- Davies, B. H., 1976. Carotenoids.In: Goodwin, T. W., eds., The Biochemistry of Carotenoids, Academic Press, N. Y., p. 38–165.Google Scholar
- Imada, N., Kobayashi, K., Tahara, K., et al., 1991. Production of an autoinhibitor bySkeletonema costatum and its effect on the growth of other phytoplankton.Nippon Suisan Gakkaishi 57(12): 2285–2290.Google Scholar
- Imada, N., Kobayashi, K., Isomura, K. et al., 1992. Isolation and identification of an autoinhibitor produced bySkeletonema costatum.Nippon Suisan Gakkaishi 58(8): 1687–1692.Google Scholar
- Mast, S. O., Pace, D. M., 1938. The effect of substances produced byChilomonas paramecium on the rate of reproduction.Physiol. Zool. XI (4): 359–382.Google Scholar
- Sun, Y. N., Yin, M. Y., Liu, J. G., 2001. Auto-signals inHaematococcus pluvialis.Transaction of Oceanol. and Limnol. 3: 22–28.Google Scholar