Investigation of bioethanol production from jatropha deoiled cake and its blending effects for environmental sustainability.

This paper describes the process of extracting ethanol from Jatropha curcas and its various blending effects on spark-ignited engine performance for environmental sustainability. Alternatives to conventional fuel sources have to be found because of the depletion of fossil fuels and stringent regulations. Every day, the growing population and improved transportation increase the energy demand. Bioethanol is an effective substitute for gasoline and SI engine diesel. Worldwide, passenger cars typically blend 10% bioethanol with gasoline. Some nations, like India, have stated plans to blend 20% bioethanol with gasoline starting shortly. From leftover jatropha deoiled cake (JDC), bioethanol was produced utilizing the fermentation and vacuum distillation methods. Four different blends were prepared on a volumetric basis at different engine speeds at a constant compression ratio of 10:1 and the wide-open throttle was tested for various performances and emissions. Bioethanol enrichments reduce CO and CO2 emissions but increase nitrogen oxide emissions. JDCE 15 was found to have the best engine performance out of all the fuel blends tested. This study suggests that, if NOx emission reduction measures are carried out, JDC can be used as a source for the manufacturing of second-generation bioethanol.

Different pre-treatments and kinetic models for bioethanol production from lignocellulosic biomass: A review.

Lignocellulosic biomass is the generally explored substrate to produce bioethanol for environmental sustainability due to its availability in abundance. However, the complex network of cellulose-hemicellulose-lignin present in it makes its hydrolysis as a challenging task. To boost the effectiveness of conversion, biomass is pre-treated before enzymatic hydrolysis to alter or destroy its original composition. Enzymes like Cellulases are widely used for breaking down cellulose into fermentable sugars. Enzymatic hydrolysis is a complex process involving many influencing factors such as pH, temperature, substrate concentration. This review presents major four pre-treatment methods used for hydrolysing different substrates under varied reaction conditions along with their mechanism and limitations. A relative comparison of data analysis for most widely studied 10 kinetic models is briefly explained in terms of substrates used to get the brief insight about hydrolysis rates. The summary of pre-treatment methods and hydrolysis rates including cellulase enzyme kinetics will be the value addition for upcoming researchers for optimising the hydrolysis process.

Different particle size study of castor deoiled cake for biofuel production with an environmental sustainability perspective.

Agro-industrial waste material such as non-edible deoiled Castor bean cake (CBC) is one of the most abundant sources for bioethanol demonstrating the feasibility of utilizing bioethanol as commercial biofuel. This is an alternative to mitigate fossil fuel dependence and carbon dioxide accumulation in the atmosphere. The CBC was pretreated with the help of thionyl chloride at a temperature of 35 °C for residence time 25 min. Subsequently, CBC substrate obtained from pretreatment was subjected to enzymatic hydrolysis with T. viride concentration varying from 0.5 to 5 g L-1 at 35 °C, pH 6 for 48 h. Under optimized conditions the process integrating pretreatment followed by enzymatic hydrolysis for 48 h at 35 °C with pH 7 resulted in 76 g L-1 of reducing sugars from 100 g CBC. The obtained sugar was further fermented at 30 °C for 72 h with saccharomyces cerevisiae as a fermenting media which yields 37.5 g L-1 of bioethanol. A study of different particle sizes of CBC with BSS-5, BSS-10, BSS-20 was done for efficient enzymatic hydrolysis and fermentation into bioethanol. On a pilot-scale 375 g L-1 of bioethanol was obtained from 1 kg of CBC with the same reaction conditions. The present study demonstrates optimized solid: liquid ratio 1:2 for hydrolysis, fermentation process, and the production cost for bioethanol per L. Figure S1 represents graphical abstract for the production of bioethanol from CBC in supplementary information.

Hypoglycaemic and hypolipidaemic effects of low GI and medium GL Indian diets in type 2 diabetics for a period of 4 weeks: a prospective study.

This prospective study reports significant hypoglycaemic and hypolipidaemic effects in type 2 diabetic subjects who were provided the complete diet plan to be on low glycaemic index (GI) and low-medium glycaemic load (GL) Indian vegetarian snacks and mixed meals for 4 continuous weeks. Five millilitres of fasting blood sample drawn at weekly intervals for 4 weeks were analysed for blood glucose, HbA1c and lipid profile. Four weeks later mean blood glucose level of 173.6 mg% decreased to 137.8 mg%, HbA1c of 8% also decreased to 7.1% which reflected the blood glucose level during the study period and hence correlated well with the fall in blood glucose level. Triglyceride level of 244.5 mg% decreased to 164.7 mg% (p < 0.0001) and total cholesterol of 173.5 mg% decreased to 134.6 mg% (p < 0.0001). High-density lipoprotein cholesterol of 33 mg% increased to 39.8 mg% (p < 0.003), very low density lipoprotein (VLDL) cholesterol of 48.9 mg% decreased to 32.9 mg% (p < 0.0001) and low-density lipoprotein cholesterol of 90.1 mg% decreased to 64.3 (p < 0.009). This significant outcome can be improved further if compliance to low GI and low-to-medium GL diet is continued. This may achieve desired glycaemic control and that's limit oxidative stress.

Traditional Indian snacks modified to attain low glycaemic index and confirmed suitable to be consumed without hyperglycaemic effect in type 2 diabetics.

The purpose of this study is to determine the glycaemic index of seven traditional Indian snacks modified in composition and preparation and to determine their glycaemic and insulinaemic response in type II diabetics. Blood glucose and insulin level at fasting, postprandial - 1 hour and 2 hours in ten normal healthy volunteers were analysed after oral administration of 50 g pure glucose and later at weekly intervals with each of the test snack. Area under curve was calculated and compared for pure glucose and each test snack to determine the glycaemic index. Each of the test snack was administered in ten type II diabetics and the glycaemic and insulinaemic response was determined at fasting, postprandial - 1 hour, 2 hours and compared with that of the normal volunteers. Changes in blood glucose and insulin levels (mean +/- SD) at fasting and two time Intervals in normal and diabetics were analysed using Student's paired 't' test, and between the two groups using Student's unpaired 't' test for each test snack. Sensory evaluation and satiety factor were obtained using five-point hedonic and visual assessment scale. Area under curve for each test snack was significantly lower (p < 0.001) than that of pure glucose and hence all the snacks are confirmed as having low glycaemic index which ranged from 31 to 47%. The significant rise at postprandial - 1 hour (p < 0.001) and fall at postprandial - 2 hours (p < 0.001) in blood glucose levels and sustained Insulin levels at postprandial - 2 hours was similar in normal and diabetics for each of the test snack. Sensory evaluation and satiety factor were similar for traditional and modified snacks. The seven modified traditional Indian snacks have low glycaemic index and do not have a hyperglycaemic effect in type II diabetics. Besides, their low glycaemic index status, high acceptability, and satiety factor makes these modified snacks most suitable for sustained consumption by type II diabetics and hence better glycaemic control.

Effect of redesigned Indian mixed meals on blood glucose and insulin levels in normal versus type 2 diabetic subjects--a comparative study.

This study reports the glycemic as well as insulinemic response of seven types of Indian vegetarian mixed meals (MMs). Each of the seven MMs was given at weekly intervals to both normal and type 2 diabetic subjects on the same day to reduce variations in food preparations. In this Indian study, each MM consisted of five to six food items with a low glycemic index (GI) ranging from 28.98 to 46.12%, glycemic load ranging from 15.58 to 23.8 g and energy value (calculated) from each test meal ranging from 403 to 502 kcal. All the seven meals were found to have postprandial glycemic control in normal subjects which ranged from 86 to 102.4 mg%, and a good postprandial glycemic control in type 2 diabetic subjects which ranged from 132.8 to 148.4 mg%, and hence appropriate for routine consumption by diabetic subjects. The glycemic and insulinemic pattern of all these MMs was similar in normal and diabetic subjects. Sustained intake of such low GI MMs by diabetic can result in good glycemic control.