Morales-Oyervides Lourdes, Oliveira Jorge, Sousa-Gallagher Maria, Méndez-Zavala Alejandro, Montañez Julio Cesar
School of Engineering, University College Cork, Cork, Ireland.
Department of Chemical Engineering, Universidad Autónoma de Coahuila, Saltillo 25280, Mexico.
J Fungi (Basel). 2017 Jun 27;3(3):33. doi: 10.3390/jof3030033.
A high percentage of the pigments produced by spp. remains inside the cell, which could lead to a high product concentration inhibition. To overcome this issue an extractive fermentation process, perstraction, was suggested, which involves the extraction of the intracellular products out of the cell by using a two-phase system during the fermentation. The present work studied the effect of various surfactants on secretion of intracellular pigments produced by spp. in submerged fermentation. Surfactants used were: non-ionic surfactants (Tween 80, Span 20 and Triton X-100) and a polyethylene glycerol polymer 8000, at different concentrations (5, 20, 35 g/L). The highest extracellular pigment yield (16 OD) was reached using Triton X-100 (35 g/L), which was 44% higher than the control (no surfactant added). The effect of addition time of the selected surfactant was further studied. The highest extracellular pigment concentration (22 OD) was achieved when the surfactant was added at 120 h of fermentation. Kinetics of extracellular and intracellular pigments were examined. Total pigment at the end of the fermentation using Triton X-100 was 27.7% higher than the control, confirming that the use of surfactants partially alleviated the product inhibition during the pigment production culture.
某菌种产生的大部分色素保留在细胞内,这可能导致高产物浓度抑制。为克服这一问题,有人提出了一种萃取发酵工艺——渗透萃取,即在发酵过程中使用双相系统将细胞内产物从细胞中萃取出来。本研究考察了各种表面活性剂对某菌种在深层发酵中分泌细胞内色素的影响。所用表面活性剂为:非离子表面活性剂(吐温80、司盘20和曲拉通X-100)以及聚乙二醇聚合物8000,浓度分别为5、20、35 g/L。使用曲拉通X-100(35 g/L)时细胞外色素产量最高(16 OD),比对照(未添加表面活性剂)高出44%。进一步研究了所选表面活性剂添加时间的影响。在发酵120 h时添加表面活性剂,细胞外色素浓度最高(22 OD)。考察了细胞外和细胞内色素的动力学。使用曲拉通X-100发酵结束时的总色素比对照高27.7%,证实了表面活性剂的使用在一定程度上缓解了色素生产培养过程中的产物抑制。