Sunanda Chanda

Plant origin liquid waste: A resource for singlecell protein production by yeast

Abstract Leaf protein was separated by heat coagulation (80°C) from leaf juices of four cruciferous plants: turnip (Brassica campestris L.), mustard (Brassica nigra Koch.), radish (Raphanus sativus L.) and cauliflower (Brassica oleracea L. var. botrytis). Three yeasts, Saccharomyces cerevisiae, Torula utilis and Candida lipolytica, were grown in deproteinized leaf juices (DLJ) of these plants. The yeast cells produced in these wheys were found to be rich in protein and vitamins. The chemical oxygen demand (COD) and biological oxygen demand (BOD) values of DLJ samples were reduced significantly by the growth of yeasts.

Effectiveness of inoculation with isolated Geobacillus strains in the thermophilic stage of vegetable waste composting.

An inoculum containing two amylolytic and three cellulolytic thermophilic bacteria, isolated from a preceding compost pile and identified as Geobacillus species by 16S rRNA gene sequencing, was applied to a mixture of market waste, rice straw and cow dung (5:1:0.2) so that the initial cell density was 2 x 10(8) colony forming unit (CFU) per gram dry weight at 55 degrees Celsius. The inoculation increased the total cell count particularly in the thermophilic stage as determined by flow cytometry. Concomitantly, there was a significant rise in microbial metabolism in the compost pile as reflected by the dehydrogenase activity. As a result, the C/N ratio dropped more rapidly in the inoculated mixture than that in the control without inoculum. The study, therefore, suggested that inoculation by thermophilic bacteria would be effective in the composting process at least in the thermophilic stage.

Recycling of jute waste for edible mushroom production

Abstract Lignocellulosic jute waste products, viz. leaves, stick and caddis, generated in large quantities from jute cultivation and industry were used as separate substrates and in admixture with rice straw in a 1:1 ratio for the production of the edible mushroom Pleurotus sajor-caju (Fr.) Singer. While growth of mushroom mycelia was hindered on jute leaves, jute stick and caddis separately, and as mixed substrates with rice straw, were found to produce a good yield of the mushroom. The chemical and mineral analyses and neutral sugar composition of the mushroom fruit bodies are reported. It was found that the efficiency of jute wastes as substrates for the production of P. sajor-caju is better than other lignocellulosic substrates, such as sugarcane bagasse and paper wastes, but more or less similar to sorghum stalk and cotton wastes.

A comparative evaluation of antibacterial potential of some plants used in indian traditional medicine for the treatment of microbial infections

A comparative in vitro antibacterial potential of extracts (aqueous and ethanol) of five important medicinal plants (Aegle marmelos, Azadirachta indica, Terminalia chebula, Mangifera indica and Ocimum sanctum) were investigated using microbial growth inhibition assays against the common human pathogenic bacteria (Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli) of clinical origin. All the plant materials showed varying degrees of strain specific inhibitory action and ethanol extract of the plant materials showed higher antibacterial activity than their aqueous counterparts. Besides, T. chebula and A. marmelos had the strongest antibacterial activity out of which, T. chebula possessed a wider spectrum and a superior antibacterial potential over the others. The bioactive compounds of T. chebula might have potential as therapeutic agents for the treatment of common bacterial infections.

Extractability and nutritional value of leaf protein from tropical aquatic plants

In a study conducted on the extraction of protein from the leaves of 30 freshwater aquatic plants, the highest standing crop fresh yield was found inTypha latifolia (2650g/m2). The Bio-Medical Data Processing (BMDP)K-means clustering program withK=2 showed that 11 of the 30 plants had a high protein nitrogen extractability as well as a high nitrogen content of the extracted protein. Among these, leaf protein fromAllmania nodiflora had the highest content of crude protein (62.7%) and β-carotene (782.4 μg/g). Leaf protein prepared fromHygrophila spinosa, Ottelia alismoides andPolygonum barbatum had low in-vitro digestibility. The levels of alkaloids and polyphenols were lower in the extracted protein compared to that present in the original leaf sample.

Citric acid production in liquid waste from a leaf-protein production plant: effects of sugar and potassium ferrocyanide.

Abstract Production of citric acid on wastes from leaf-protein production fortified with molasses and potassium ferrocyanide appears to be a commercial proposition.

Chemical characterization of pressed fibrous residues of four aquatic weeds

Abstract The pressed fibrous residues, generated as a by-product during the large-scale manufacture of leaf protein from four aquatic weeds,Pistia stratiotes L. var.cuneata Engl. (Araceae),Nymphoides cristatum (Roxb.) O. Kuntze (Gentianaceae),Lemna perpusilla Torr. (Lemnaceae) andAllmania nodilflora (L.) R.Br.ex Hook.f. (Amaranthaceae), were analysed for their chemical and mineral composition. They were found to consist of lignin, cellulose, pentosan, lipid, pectin and minerals.Pistia stratiotes is a rich source of α-cellulose (40.63%),A. nodiflora andN. cristatum contain pentosan and pectin (19.75% and 14.49%, respectively), whileL. perpusilla shows comparatively larger amounts of minerals (ash content 15%). All the values obtained were compared with those of other similar aquatic weeds and agricultural wastes such as rice and wheat straw, grass, bagasse, etc., which are usually used in the preparation of silage, compost, biogas and several other products.

Chemical characterization of the stem of Cyperus tegetum — A semi-aquatic plant of economic importance

Abstract Cyperus tegetum Roxb. is a perennial herb growing naturally in marshy land in the humid tropics including India. The stem of the plant is used for making mats for floor covering as well as decoration, and this is a remunerative occupation for people in the rural areas in India. Analyses of the stem of C. tegetum grown under different fertilizer doses for increasing yield showed no significant variations in compositions. The stem was lignocellulosic and similar in contents of major constituents to straws, bagasse, grasses, etc. The stem being acidic could have a strong affinity to basic dyes for attractive colour finishing of mats, though the high crude fat content might inhibit good colouration. The strength properties of upper, middle and lower portions of stem measured by breaking load indicated higher strength in the middle portion than other parts of the stem.

Chemical evaluation of leaf fibre from four tropical trees: A social forest resource

Abstract Leaf-fibre residues, generated as by-products during large-scale manufacture of leaf protein meal from forest trees, were analysed. The fibres were found to consist of lignin, α-cellulose, pentosan, lipid, pectin and minerals. The values obtained were compared with other lignocellulosic wastes and by-products such as straw, husk, jute stick, fibres, wood, etc., which are usually used in the preparation of feed, pulp, particle-boards, paper, and composts.

Chemical Evaluation of Leaf Fibre Residues from Tropical Tree Legumes—a Wealth in Social Perspective

SYNOPSIS Leaf fibre residues obtained as a by-product during bulk extraction of leaf protein meal from three tropical forest trees viz. Albizzia procera Benth., Dalbergia sisso Roxb. and Delonix regia Raf. were analysed for their chemical and mineral composition. The fibres were found to consist of lignin, α-cellulose, pentosan, lipids, minerals, etc. and were similar in chemical nature. The data were compared with those of other lignocellulosic wastes and agricultural by-products like straw, husk, bagasse, jute stick, fibres, wood etc., which are commercially used in the preparation of feed, pulp, particle board, paper and composts.