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Aims:  To access inulinase production by Xanthomonas campestris pv phaseoli using the submerged and solid state cultivation (SSC) methods. Methods and Results:  Various carbon sources, inulin‐rich solid substrates and pure synthetic inulin were tested for their efficiency in inulinase induction. The highest inulinase production (17·42 IU ml−1) in submerged cultures of X. campestris was observed with inulin as a carbon source with an initial pH, temperature and agitation of 7·0, 37°C and 150 rev min−1 respectively. Among the various substrates, garlic peels (117 IU gds−1) and onion peels (101 IU gds−1) were found to be the best for inulinase production. Conclusion:  The inulinase production level of X. campestris was 6·7‐fold higher in garlic and 5·8‐fold in onion, under optimized SSC conditions compared with the submerged culture. Significance and Impact of the Study:  This is the first report on inulinase production from garlic and onion peels by X. campestris using SSC. SSC is an efficient method for inulinase production by X. campestris for commercial applications.

The combined effect of simultaneous saccharification and fermentation and separate hydrolysis and fermentation (SHF) for ethanol production by Kluyveromyces marxianus 6556 was studied using two lignocellulosic feedstocks viz., corncob and soybean cake. The ethanologenic efficiency of K. marxianus 6556 was observed as 28% (theoretical yield) in a fermentation medium containing glucose, but, there was no ethanol production by cells grown on xylose. A maximum sugar release of 888 mg/g corncob and 552 mg/g soybean cake was achieved through acid hydrolysis pretreatment. Furthermore, corncob and soybean cake treated with commercial cellulase (100 IU for 48 h) from Trichoderma reesei yielded reducing sugars of 205 and 100 mg/g, respectively. Simultaneous saccharification and fermentation resulted in highest ethanol production of 5.68 g/l on corncob and 2.14 g/l on soybean cake after 48 h of incubation. On the contrary, the presence of inhibitors decreased the overall ethanol yield in the hydrolysates obtained through SHF of corncob and soybean cake.