Thakor Nehal, Trivedi Ujjval, Patel K C
Department of Biosciences, Sardar Patel University, Vallabh Vidyanagar 388 120, India.
Bioresour Technol. 2005 Nov;96(17):1843-50. doi: 10.1016/j.biortech.2005.01.030. Epub 2005 Apr 1.
Comamonas testosteroni has been studied for its ability to synthesize and accumulate medium chain length poly(3-hydroxyalkanoates) (mcl-PHAs) during cultivation on vegetable oils available in the local market. Castor seed oil, coconut oil, mustard oil, cotton seed oil, groundnut oil, olive oil and sesame oil were supplemented in the mineral medium as a sole source of carbon for growth and PHAs accumulation. The composition of PHAs was analysed by a coupled gas chromatography/mass spectroscopy (GC/MS). PHAs contained C6 to C14 3-hydroxy acids, with a strong presence of 3-hydroxyoctanoate when coconut oil, mustard oil, cotton seed oil and groundnut oil were supplied. 3-hydroxydecanoate was incorporated at higher concentrations when castor seed oil, olive oil and sesame oil were the substrates. Purified PHAs samples were characterized by Fourier Transform Infrared (FTIR) and 13C NMR analysis. During cultivation on various vegetable oils, C. testosteroni accumulated PHAs up to 78.5-87.5% of the cellular dry material (CDM). The efficiency of the culture to convert oil to PHAs ranged from 53.1% to 58.3% for different vegetable oils. Further more, the composition of the PHAs formed was not found to be substrate dependent as PHAs obtained from C. testosteroni during growth on variety of vegetable oils showed similar compositions; 3-hydroxyoctanoic acid and/or 3-hydroxydecanoic acid being always predominant. The polymerizing system of C. testosteroni showed higher preference for C8 and C10 monomers as longer and smaller monomers were incorporated less efficiently.
已对睾丸酮丛毛单胞菌进行研究，以考察其在以当地市场可得植物油为培养基进行培养期间合成和积累中链长度聚（3-羟基脂肪酸酯）（mcl-PHAs）的能力。在矿物培养基中添加蓖麻油、椰子油、芥子油、棉籽油、花生油、橄榄油和芝麻油，作为生长和积累PHA的唯一碳源。通过气相色谱/质谱联用仪（GC/MS）分析PHA的组成。PHA含有C6至C14的3-羟基酸，当提供椰子油、芥子油、棉籽油和花生油时，3-羟基辛酸大量存在。当以蓖麻油、橄榄油和芝麻油为底物时，3-羟基癸酸的掺入浓度较高。通过傅里叶变换红外光谱（FTIR）和13C核磁共振分析对纯化的PHA样品进行表征。在以各种植物油为培养基进行培养期间，睾丸酮丛毛单胞菌积累的PHA高达细胞干物质（CDM）的78.5-87.5%。对于不同的植物油，该培养物将油转化为PHA的效率在53.1%至58.3%之间。此外，未发现所形成的PHA的组成依赖于底物，因为在以多种植物油为培养基生长期间从睾丸酮丛毛单胞菌获得的PHA显示出相似的组成；3-羟基辛酸和/或3-羟基癸酸总是占主导地位。睾丸酮丛毛单胞菌的聚合系统对C8和C10单体表现出更高的偏好，因为较长和较短的单体掺入效率较低。
