Wongwatanapaiboon Jinaporn, Kangvansaichol Kunn, Burapatana Vorakan, Inochanon Ratanavalee, Winayanuwattikun Pakorn, Yongvanich Tikamporn, Chulalaksananukul Warawut
Program in Biotechnology, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
J Biomed Biotechnol. 2012;2012:303748. doi: 10.1155/2012/303748. Epub 2012 Oct 14.
The grasses in Thailand were analyzed for the potentiality as the alternative energy crops for cellulosic ethanol production by biological process. The average percentage composition of cellulose, hemicellulose, and lignin in the samples of 18 types of grasses from various provinces was determined as 31.85-38.51, 31.13-42.61, and 3.10-5.64, respectively. The samples were initially pretreated with alkaline peroxide followed by enzymatic hydrolysis to investigate the enzymatic saccharification. The total reducing sugars in most grasses ranging from 500-600 mg/g grasses (70-80% yield) were obtained. Subsequently, 11 types of grasses were selected as feedstocks for the ethanol production by simultaneous saccharification and cofermentation (SSCF). The enzymes, cellulase and xylanase, were utilized for hydrolysis and the yeasts, Saccharomyces cerevisiae and Pichia stipitis, were applied for cofermentation at 35 °C for 7 days. From the results, the highest yield of ethanol, 1.14 g/L or 0.14 g/g substrate equivalent to 32.72% of the theoretical values was obtained from Sri Lanka ecotype vetiver grass. When the yields of dry matter were included in the calculations, Sri Lanka ecotype vetiver grass gave the yield of ethanol at 1,091.84 L/ha/year, whereas the leaves of dwarf napier grass showed the maximum yield of 2,720.55 L/ha/year (0.98 g/L or 0.12 g/g substrate equivalent to 30.60% of the theoretical values).
对泰国的草类进行了分析，以评估其作为通过生物工艺生产纤维素乙醇的替代能源作物的潜力。测定了来自泰国不同省份的18种草类样本中纤维素、半纤维素和木质素的平均百分比组成，分别为31.85 - 38.51%、31.13 - 42.61%和3.10 - 5.64%。样本首先用碱性过氧化氢进行预处理，然后进行酶水解以研究酶促糖化作用。大多数草类中获得的总还原糖含量为500 - 600 mg/g草类（产率70 - 80%）。随后，选择了11种草类作为同时糖化和共发酵（SSCF）生产乙醇的原料。使用纤维素酶和木聚糖酶进行水解，并应用酿酒酵母和树干毕赤酵母进行在35℃下共发酵7天。结果表明，斯里兰卡生态型香根草获得的乙醇产量最高，为1.14 g/L或0.14 g/g底物，相当于理论值的32.72%。当将干物质产量纳入计算时，斯里兰卡生态型香根草的乙醇产量为1,091.84 L/公顷/年，而矮象草的叶子显示出最高产量为2,720.55 L/公顷/年（0.98 g/L或0.12 g/g底物，相当于理论值的30.60%）。
