Abstract
Cultural Conditions for the Improvement in Gibberellic Acid Productivity by a Mutant of Gibberellafujikuroi ATCC 12616-Gibberella fujikuroi G-36 . Dh, Young-Jun. Department of Food and Biotechnolog}'r Dongshm Umversity, Naju 520-714, Korea - A mutant Gibberella jujih/roi G- 36 was selected by metagenesis of G/bberella fitjikuroi ATCC 12616 with mutagens such as N-methy1-N'~nitro~N"nitrosoguanidine and hydroxylamine for improving productivity of gibberellic acid. The mutant strain produced gibberellic acid (70 mg/l) more than that of wilde type. A fermentation medium containing glucose, $NH_4N0_3$, $MgS0_4$, $KH_2P0_4$ and trace elements was deve]oped for the maximal production of a gibberellic acid by the mutanL The Guctuating cultural temperature that was vaded from 300e to 20DC resulted in higher GA yield than that of fixed cu1tura] temperature at $28^{\circ}C$.
곰팡이 Gibberella fujikuroi ATCC12616을 mutagen N-methyl-N-nitro-N-nitrosoguanidine과 hydroxylamine으로 처리하여 지베렐린 생산수률이 가장 높은 변이주 G. fujikuroi G-26을 선별하였다 변이주 G.fujikuroi G-36는 모균주 G.fujikuroi ATCC 12616 과 비교하여 볼 때 지베렐린 생산수율이 약 32% 향상된 것으로 관찰 되었다 이 균주를 액체배지에서 발효시키면 주 탄소원으로 sucrose를 사용할 때 높은 생산성을 나타내었으며 초기배지 pH와 온도는 각각 pH 4.0$ 28^{\circ}C$조건이 가장 좋았다 배양온도를 $30^{\circ}C$에서 3일 배양후 $20^{\circ}C$로 낮추어 7일간 배양하면 130mg/l의 가장 높은 지베렐린이 생성됨을 알았다.