Indian Institute of Integrative Medicine (Formerly Regional Research Laboratory) , Canal Road, Jammu Tawi- 18001 , India ; Department of Pharmacognosy, College of pharmacy, King Saud University , Riyadh, 11451 , Saudi Arabia.
Braz J Microbiol. 2012 Oct;43(4):1476-90. doi: 10.1590/S1517-838220120004000032. Epub 2012 Jun 1.
We have established methodology for the isolation and characterization of a novel endophytic fungus from the inner bark of medicinal plant Nothapodytes foetida, which produced camptothecin in Sabouraud broth (SB) under shake flask conditions. Camptothecin and its related compounds are at present obtained by extraction from intact plants, but fungal endopytes may be an alternative source of production. In present study we have observed the effect of different nutrient combinations and precursors (tryptophan, tryptamine, geraniol, citral, mevalonic acid and leucine) on the accumulation of camptothecin by endophytic fungus Entrophospora infrequens. The precursors were fed either alone or in combinations (tryptophan and geraniol, tryptophan and citral, tryptophan and mevalonic acid, tryptophan and leucine). The highest camptothecin content was observed in the range of 503 ± 25µg/100g dry cell mass in Sabouraud medium. Camptothecin content in the medium was increased by 2.5 folds by the presence of tryptophan and leucine whereas the production with trytophan was also significantly different from other treatments. Furthermore, the effect of fungal camptothecin on the morphology of human cancer cell lines was also studied. The treated cells showed reduction in size, condensation of nucleus and the protoplasmic extensions were reduced. All these characteristics are found in apoptotic cells.
我们已经建立了从药用植物印度娑罗双树的内树皮中分离和鉴定新型内生真菌的方法,该真菌在摇瓶条件下的萨布罗肉汤(SB)中产生喜树碱。喜树碱及其相关化合物目前是从完整植物中提取得到的,但真菌内生菌可能是生产的替代来源。在本研究中,我们观察了不同营养组合和前体(色氨酸、色胺、香叶醇、柠檬醛、甲羟戊酸和亮氨酸)对内生真菌 Entrophospora infrequens 积累喜树碱的影响。前体单独或组合(色氨酸和香叶醇、色氨酸和柠檬醛、色氨酸和甲羟戊酸、色氨酸和亮氨酸)进行添加。在萨布罗培养基中,观察到内生真菌 Entrophospora infrequens 产生的喜树碱含量最高为 503±25μg/100g 干细胞质量。在存在色氨酸和亮氨酸的情况下,喜树碱含量增加了 2.5 倍,而色氨酸的产生也明显不同于其他处理。此外,还研究了真菌喜树碱对人类癌细胞系形态的影响。处理过的细胞体积缩小,核浓缩,细胞质突起减少。所有这些特征都存在于凋亡细胞中。