The two microbial enzymes used in t

The two microbial enzymes used in the present study exhibited a high efficiency in the conversion of starch from fruitpeels, which was comparable with the results obtained by many other researchers [21, 46]. The saccharification ofdifferent agro-wastes has been also reported by other workers employing enzymes from different microorganisms[47]. Karakastsanis and Liakopoulu-Kyriakides [48] have observed 96% of starch conversion in corn by usingamylase and glucoamylase, simultaneously. Dettori-Campus et al. [49] have reported 80% of starch conversion inbarley, corn and rice using amylases from Bacillus species. Sharma et al. [50] have reported a maximum yield of 63 gL-1 reducing sugar after enzymatic saccharification and 0.426 gg-1 ethanol after fermentation in a mixture of bananapeels and kinnow waste. Hammond et al. [6] have reported an increased sugar recovery and ethanol production frombananas andThe fermentation efficiencies and ethanol production in the hydrolysates of fruit samples are presented in Table 3.Ethanol yield in fruit pulps varied significantly between the fruit samples and the highest yield was 35.86% in themixed fruit pulps sample, followed by 28.45% in banana pulp and the lowest yield was 26.5% in mango pulp. Thefermentation of enzymatic hydrolysate of acid pretreated mixed fruit pulps (banana and mango) by yeast showed anincubation period of 48 h as optimum for maximum ethanol of 35.86% corresponding to a fermentation efficiency of70.33%. In peels samples, the maximum yield was 13.84% in banana and 9.68% in mango at 42 h of incubation. Theresults on ethanol yield are in concert with the observations of Sirkar et al. [36] in banana. The fermentation studies onthe hydrolysates of fruit pulps obtained from both the pretreatments (LHW & DAP) with out enzymatic hydrolysishave showed poor ethanol yield and the ethanol yield was 25% lower than the normal fermentation process ofhydrolysates obtained after saccharification (Fig 2). The results are in good agreement with the previous report ofHammond et al. [6], where he has reported a ethanol yield reduction of 13.4% from the ripen banana pulp withoutenzymatic hydrolysis. Joshi et al. [51] in a fermentation study with flocculating yeast () observed that wastebanana peels are capable of providing enough sugar for the fermentation and hence can be economically utilized forethanol production. Onwuka and Awam [12] have reported 19 24% of fermentable sugar and alcohol content of 881.5 brix (9.96 11.25%) in cooking banana and plantain.The fermentation studies showed a maximum ethanol productivity of 0.747% h in mixed fruit pulps and minimum of0.230% h in mango fruit peels (Table 3). A steep increase in the ethanol productivity over the increase of yeast cellgrowth was also observed and the highest ethanol yield was observed when the yeast biomass was recorded as 10.23 gL , 4.06 g L during the fermentation of mixed fruit pulps and peels respectively (Fig 3). Similarly for banana andbanana wastes using commercial α-amylase and glucoamylase