Preliminary evaluation of five elephant grass cultivars harvested at different time for sugar production

Abstract Five elephant grass cultivars, Pennisetum purpureum . cv. Huanan (Huanan), P. purpureum . cv. N51 (N51), P. purpureum . cv. Sumu No. 2 (Sumu-2), ( Pennisetum americanum  ×  P. purpureum ) ×  P. purpureum cv. Guimu No. 1 (Guimu-1) and P. americanum cv. Tift23A ×  P. purpureum cv. Tift N51 (Hybrid Pennisetum), at three harvest stages were studied. With dilute sulfuric acid pretreatment followed by enzymatic hydrolysis, it is found that cellulose conversion of the five elephant grass cultivars harvested in August and September is higher than that harvested in October. The cellulose conversion for elephant grass cultivars harvested in August and September follows an order of Hybrid Pennisetum > Sumu-2 > Huanan > Guimu-1 > N51. This may be explained by the fact that lignification is gradually strengthened with time, inhibiting degradation of cellulose and hemicellulose. Moreover, cellulose conversions of Hybrid Pennisetum, Sumu-2 and Huanan harvested in August and September are higher based on hierarchical clustering results.