Gurunathan Baskar

Immobilization of cellulase onto MnO2 nanoparticles for bioethanol production by enhanced hydrolysis of agricultural waste

Abstract Cellulase is an efficient enzymatic catalyst that hydrolyses cellulosic substances. The high costs associated with using enzymes for industrial applications can be reduced by immobilizing the cellulase. In the current study, cellulase produced by Aspergillus fumigatus JCF was immobilized onto MnO2 nanoparticles, which improve the activity of cellulase and offer a superior support. The surface characteristics of synthesized MnO2 nanoparticles and cellulase-bound MnO2 nanoparticles were investigated by scanning electron microscopy, and Fourier transform infrared spectroscopy was used to analyze the functional characteristics of the immobilized cellulase. The maximum cellulase binding efficiency was 75%. The properties of the immobilized cellulase, including activity, operational pH, temperature, thermal stability, and reusability were investigated and were found to be more stable than for the free enzyme. It was found that cellulase immobilized on MnO2 nanoparticles could be used to hydrolyze cellulosic substances over a broad range of temperature and pH. The results confirmed that cellulase immobilized on MnO2 nanoparticles was very efficient in terms of cellulolytic activity.

Production of L-Asparaginase from Natural Substrates by Aspergillus terreus MTCC 1782: Effect of Substrate, Supplementary Nitrogen Source and L-Asparagine

In the present work, the fungal species Aspergillus terreus MTCC 1782 was used for the production of L-asparaginase using natural substrates like groundnut oil cake, cottonseed oil cake and corn flour in modified Czepak-Dox media and compared the L-asparaginase production using synthetic L-proline. The modified Czepak-Dox media with 2% L-proline, supplemented with 1% sodium nitrate and 1% L-asparagine has shown maximum L-asparaginase activity of 34.98 IU/mL on the third day of production. The modified Czepak-Dox media with 2% groundnut oil cake, 1% sodium nitrate and 1.2% L-asparagine showed maximum L-asparaginase activity of 30.35 IU/mL on the fourth day. These results are comparatively higher than the maximum L-asparaginase production reported in the literature (19.5 U/mL), by isolated Aspergillus sp. using Czepak-Dox media containing 2% (w/v) L-asparagine as the sole substrate along with 1% (w/v) ammonium sulfate as an additional nitrogen source. It is observed that the addition of L-proline or ground nut oil cake increases the L-asparaginase production. The groundnut oil cake is found as the potential natural and cheaper substrate for L-asparaginase production by Aspergillus terreus MTCC1782.

Production and optimization of cellulase from agricultural waste and its application in bioethanol production by simultaneous saccharification and fermentation

Purpose – The purpose of this paper is to optimize production of cellulase enzyme from agricultural waste by using Aspergillus fumigatus JCF. The study also aims at the production of bioethanol using cellulase and yeast. Design/methodology/approach – Cellulase production was carried out using modified Mandel’s medium. The optimization of the cellulase production was carried out using Plackett-Burman and Response surface methodology. Bioethanol production was carried out using simultaneous saccharification and fermentation. Findings – Maximum cellulase production at optimized conditions was found to be 2.08 IU/ml. Cellulase was used for the saccharification of three different feed stocks, i.e. sugar cane leaves, corn cob and water hyacinth. Highest amount of reducing sugar was released was 29.1 gm/l from sugarcane leaves. Sugarcane leaves produced maximum bioethanol concentration of 9.43 g/l out of the three substrates studied for bioethanol production. Originality/value – The present study reveals that by...

Overview on mitigation of acrylamide in starchy fried and baked foods: Acrylamide mitigation in starchy fried and baked foods

Acrylamide in fried and baked foods has the potential to cause toxic effects in animals and humans. A major challenge lies in developing an effective strategy for acrylamide mitigation in foods without altering its basic properties. Food scientists around the world have developed various methods to mitigate the presence of acrylamide in fried food products. Mitigation techniques using additives such as salts, amino acids, cations and organic acids along with blanching of foods have reduced the concentration of acrylamide. The use of secondary metabolites such as polyphenols also reduces acrylamide concentration in fried food products. Other mitigation techniques such as asparaginase pre-treatment and low-temperature air frying with chitosan have been effective in mitigating the concentration of acrylamide. The combined pre-treatment process along with the use of additives is the latest trend in acrylamide mitigation.