Central Tuber Crops Research Institute

About: Central Tuber Crops Research Institute is a facility organization based out in Thiruvananthapuram, Kerala, India. It is known for research contribution in the topics: Starch & Fermentation. The organization has 475 authors who have published 587 publications receiving 10285 citations.

Indole-3-acetic acid production and effect on sprouting of yam (Dioscorea rotundata L.) minisetts by Bacillus subtilis isolated from culturable cowdung microflora.

Abstract: Bacillus subtilis strains (CM1-CM5) isolated from culturable cowdung microflora were investigated for indole-3-acetic acid (IAA) production in nutrient broth (NB). All the strains tested produced IAA in NB; albeit in very low concentrations (0.09 n 0.37 mg/l). The addition of L-tryptophan (0.1 n 1.0 g/l) into NB substantially enhanced IAA production (6.1 n 31.5 folds) indicating that L-tryptophan was the precursor for IAA biosynthesis by these bacterial strains. Maximum IAA production was observed after 8 days of incubation (in late stationary phase of bacterial growth). The variation in IAA production was attributed to the genetic make up of these strains as evaluated by RAPD analysis of these isolates and B. subtilis type strain MTCC 441. Application of B. subtilis suspension (8 ◊1 0 9 CFU/ml) on the surface of yam (Dioscorea rotundata L.) minisetts increased the number of sprouts, roots and shoots length, root and shoot fresh weights and root: shoot ratio over those minisetts not treated with bacterial suspension. Fresh cowdung slurry treatment on yam minisetts also produced similar results as obtained with B. subtilis application.

Raman and infrared spectra of starch samples of sweet potato and cassava.

Abstract: Raman and infrared spectra of starch samples from sweet potato and different varieties of cassava (tapioca) are reported. Three regions of the spectra, the OH stretching region (3560-3000cm-1), the CH stretching region (3000-2800cm-1) and the finger print region (1600-200cm-1), have been studied. The results are discussed in relation to the hydrogen bonding and the properties of starch samples.

Process optimization for bioethanol production from cassava starch using novel eco-friendly enzymes

Abstract: Although cassava (Manihot esculenta Crantz) is a potential bioethanol crop, high operational costs resulted in a negative energy balance in the earlier processes. The present study aimed at optimizing the bioethanol production from cassava starch using new enzymes like Spezyme® Xtra and Stargen™ 001. The liquefying enzyme Spezyme was optimally active at 90 °C and pH 5.5 on a 10% (w/v) starch slurry at levels of 20.0 mg (280 Amylase Activity Units) for 30 min. Stargen levels of 100 mg (45.6 Granular Starch Hydrolyzing Units) were sufficient to almost completely hydrolyze 10% (w/v) starch at room temperature (30 ± 1 °C). Ethanol yield and fermentation efficiency were very high (533 g/kg and 94.0% respectively) in the Stargen + yeast process with 10% (w/v) starch for 48 h. Raising Spezyme and Stargen levels to 560 AAU and 91.2 GSHU respectively for a two step loading [initial 20% (w/v) followed by 20% starch after Spezyme thinning]/initial higher loading of starch (40% w/v) resulted in poor fermentation efficiency. Upscaling experiments using 1.0 kg starch showed that Stargen to starch ratio of 1:100 (w/w) could yield around 558 g ethanol/kg starch, with a high fermentation efficiency of 98.4%. The study showed that Spezyme level beyond 20.0 mg for a 10% (w/v) starch slurry was not critical for optimizing bioethanol yield from cassava starch, although an initial thinning of starch for 30 min by Spezyme facilitated rapid saccharification–fermentation by Stargen + yeast system. The specific advantage of the new process was that the reaction could be completed within 48.5 h at 30 ± 1 °C.