Anshu Singh

Composting of a crop residue through treatment with microorganisms and subsequent vermicomposting.

Preliminary studies were conducted on wheat straw to test the technical viability of an integrated system of composting, with bioinoculants and subsequent vermicomposting, to overcome the problem of lignocellulosic waste degradation, especially during the winter season. Wheat straw was pre-decomposed for 40 days by inoculating it with Pleurotus sajor-caju, Trichoderma harzianum, Aspergillus niger and Azotobacter chroococcum in different combinations. This was followed by vermicomposting for 30 days. Chemical analysis of the samples showed a significant decrease in cellulose, hemicellulose and lignin contents during pre-decomposition and vermicomposting. The N, P, K content increased significantly during pre-decomposition with bioinoculants. The best quality compost, based on chemical analysis, was prepared where the substrate was treated with all the four bioinoculants together followed by vermicomposting. Results indicated that the combination of both the systems reduced the overall time required for composting and accelerated the composting of ligno-cellulosic waste during the winter season besides producing a nutrient-enriched compost product.

Effect of Microbial Inocula on Mixed Solid Waste Composting, Vermicomposting and Plant Response

To accelerate the process of composting, different microflora viz. Pleurotus sajor-caju (fungus), Trichoderma harzianum (fungus) and Azotobacter chroococcum (bacteria) were inoculated in different combinations into mixed solid waste, a mixture of municipal solid waste (MSW) and horticultural waste in the ratio of 70:30. The waste was decomposed for different time periods and then subjected to subsequent vermicomposting for a fixed period of one month. The compost produced was evaluated for nutrient levels and effects on mung bean (Vigna radiata) growth. A significant difference was observed in the quality of compost produced with the bioinoculants over control treatments where no bioinoculant was used. The combination of P. sajor-caju, T. harzianum and A. chrocooccum produced the highest quality compost. The percentage of mycorrhizal infection in mung bean was influenced by the three inoculants and crop growth was enhanced significantly with the combination of P. sajor-caju, T. harzianum and A. chrocooccum over other treatments.

Kinetic and mechanistic investigations of the Baylis–Hillman reaction in ionic liquids

We report here a quantitative study of the kinetics and mechanism of the Baylis–Hillman reaction in the presence of ionic liquids as solvent media. Apparently, a simple Baylis–Hillman reaction can occur by two different exclusive mechanisms in ionic liquids. The delicate balance of these mechanisms is maintained by the ionic environment employed. The main features of the possible mechanism have been described here along with interesting kinetic consequences. The measurement of rate constants and activation energy parameters demonstrate that as the medium becomes basic, the order of the reaction changes from 1 to 2. An unexpected change in the mechanism of the reaction is observed with a change in the nature of the ionic liquid. The Linear Solvation Energy Relationship has also been used as an investigating tool to delineate the respective contributions of the cation and anion of the ionic liquid. The observation strongly dictates the dependency of the mechanism of the Baylis–Hillman reaction on the nature of the anion of the ionic liquids undertaken for this study.

Comparative analysis of solid-state bioprocessing and enzymatic treatment of finger millet for mobilization of bound phenolics.

The present work investigates the probable bioprocessing technique to mobilize the bound phenolics naturally found in finger millet cell wall for enriching it with dietary antioxidants. Comparative study was performed between the exogenous enzymatic treatment and solid-state fermentation of grain (SSF) with a food grade organism Rhizopus oryzae. SSF results indicated that at the 6th day of incubation, total phenolic content (18.64xa0mg gallic acid equivalent/gds) and antioxidant property (DPPH radical scavenging activity of 39.03xa0%, metal chelating ability of 54xa0% and better reducing power) of finger millet were drastically enhanced when fermented with GRAS filamentous fungi. During the enzymatic bioprocessing, most of the phenolics released during the hydrolysis, leached out into the liquid portion rather than retaining them within the millet grain, resulting in overall loss of dietary antioxidant. The present study establishes the most effective strategy to enrich the finger millet with phenolic antioxidants.

Peptide enriched functional food adjunct from soy whey: A statistical optimization study

Soy whey is generated as a process waste while preparing soy based food products tofu, causing environmental pollution and also representing an economic penalty against the industrial process. Therefore, its valorization is of prime importance to the industry. The present investigation aims to convert this proteinaceous waste into bioactive peptide enriched hydrolysate. Soy whey protein was enzymatically treated with the Aspergillus awamori nakazawa protease. Respective protease was efficient to produce antioxidant peptide beholding radical scavenging ability of 40–50% at normal conditions. Remarkable increase in the radical scavenging activity upto 70% was noticed at the response surface methodology (RSM) based optimized condition: temperature 40°C, salt concentration (NaCl) 0.05 M, surfactant concentration (Triton-X 100) 0.0075%, hydrolysis time 80 min, and enzyme to substrate concentration 164 IU/g of soy whey protein. The present study emphasizes the biotransformation of proteineceous waste into antioxidant peptide rich soy whey protein hydrolysate to be considered as additives for food preparation and formulation.

Enzymatic polishing of cereal grains for improved nutrient retainment

Consumer acceptance of food products is largely driven by the dietary and functional quality of their ingredients. Though whole cereal grains are well known for bioactive components, scientists are facing dire need for better technologies to prevent the nutritional losses incurred through the conventional food processing technologies. Application of enzyme for depolymerisation of carbohydrates present in bran layer of grain is becoming an efficient method for phenolic mobilization and dietary fiber solubilisation. The present article emphasizes deep insights about the application of enzyme as an alternative technology for cereal grain processing to improve the product quality while forbidding the nutritional losses in an eco-friendly manner.

Study and optimization of adsorption of sulfur compounds present in fuel

The present work investigates the performance of fly ash, coal dust, bentonite, laterite and sodium zeolite as adsorbents for desulfurization of synthetic fuel by batch adsorption experiments at 50 °C and under atmospheric pressure. A series of synthetic fuel samples containing known concentrations of thiophenol, benzothiophene and di-benzothiophene, as singular and multi component mixtures in isooctane, were prepared. The performance of coal dust was found to be the best among all the adsorbents mentioned, in removal of both single and multi sulfur compounds from synthetic fuel. The adsorbents were characterized by BET surface area analysis, XRF, XRD, FTIR, SEM and NH3-TPD. The effects of parameters such as stirrer speed, adsorbent particle size, temperature, adsorbent amount, initial sulfur concentration and contact time between adsorbate and adsorbent were investigated for desulfurization of synthetic fuel using coal dust as adsorbent. The sulfur adsorption equilibrium with this adsorbent was fitted to Langmuir, Freundlich, BET, Halsey and Temkin isotherms. Finally Response Surface Methodology (RSM) was applied for optimizing the adsorption process parameters. The four factor Box–Behnken design (BBD) was performed, aimed at developing second order polynomial models at the optimum conditions. The objective was to find out how the output, sulfur adsorption per gram of adsorbent (qt), is related to the inputs, initial sulfur concentration, adsorbent amount, time and temperature, in order to get a clear picture for further research.

Biotransformation of hydrolysable tannin to ellagic acid by tannase from Aspergillus awamori

Abstract Madhuca indica, locally known as mahua in India is a multipurpose tree species. Mahua, particularly bark contains a significant amount of hydrolysable tannin (17.31%) which can be utilized for ellagic acid production through biotransformation. In the present study, mahua bark utilized not only as a raw material for tannase production but also for ellagic acid a well-known therapeutic compound. After prior confirmation of hydrolysable tannin content in bark, it has been supplemented, as a substrate for tannase production through solid state fermentation of Aspergillus awamori. Tannase production, as well as biodegradation of the hydrolysable tannin reached a maximum at 72u2009h of incubation time. The optimum conditions for tannase production are solid to liquid ratio of 1:2, 35u2009°C, pH 5.5 and 72h incubation time which resulted 0.256u2009mg/mL of an extract of ellagic acid. Maximum tannase activity of 56.16u2009IU/gds at 35u2009°C and 72h of incubation time is recorded. It seems that tannase production and biotransformation of hydrolysable tannins using bark powder of mahua can be considered as an appropriate alternative to the existing procedures of ellagic acid production.

Enzymatic Peeling of Potato: A Novel Processing Technology

Development of an innovative biotechnological method for potato peeling, closer to the ‘ideal’ peeling conditions of the product, was the main objective of the present research. Studies on enzymatic hydrolysis of potato peel were conducted. The efficacy of enzymatic peel hydrolysis was expressed in terms of reducing sugar content of the enzyme solution in which potato peel was incubated. Enzyme screening revealed that an enzyme solution containing a cellulase-xylanase mixture and amylase in a ratio of 1:1 showed good peel hydrolyzing efficiency of peeled peels. To further maximise the peel hydrolysis, condition parameters were optimised using response surface methodology (RSM). At the optimised conditions of 60xa0°C, pH 6 and 4xa0h, the reducing sugar yield in the solution was maximum. Characterization of the potato peel using microscopic techniques (scanning electron microscopy (SEM), atomic force microscopy (AFM)) further illustrated degradation of cell wall and reduction in the surface roughness of the peel after enzymatic treatment, which could enhance peel loosening from the intact potato. To further ascertain the efficiency of the process, studies were conducted with the selected enzyme on intact potato tubers under optimised conditions. Easy removal of peel was observed in enzyme-treated potato tubers, which showed 0.52% peel loss by abrasive peeling. The present process employing enzymes could be applied for peeling of intact potato as an alternative to conventional peeling process.

Oleaginous Fungi: A Solution to Oil Crisis

Oleaginous fungi are known for microbial oil as they can accumulate intracellular lipid up to 70% under stress condition. Like vegetable oils, microbial oils component is TAG, composed of C16 and C18 series long chain fatty acids, due to which microbial lipids can be subjected to transesterification process. High growth rate, short generation time and high lipid content of oleaginous microorganism, under specific conditions, open new prospects for scaling up the cultivation. Although microbial lipid content is high in such microorganism, but process optimization and isolation of organism that can grow on cheap sources of carbon, would add advantage to the production system. Oil from oleaginous fungi has given a new turn to the fuel generation and to the food industries, as their lipid is rich in TAG and the specific PUFA. With the increase in population, demand for food is also soaring, in such scenario food based fuel production will be highly expensive and unwise option, a promising alternative is to look at microbial oil technology as it doesn’t compete with the farmland for crop production. The present chapter focuses on the growth, mechanism and regulation of lipid accumulation in oleaginous filamentous fungi.