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The magnetically separable heterogeneous nickel–zinc ferrite (NiZnFe2O4) catalyst was synthesized and used for the first time as an environmentally friendly reusable catalyst for the synthesis of 2-amino-4H-chromene derivatives via a one-pot, three-component condensation reaction of various salicylaldehydes and malononitrile or ethyl cyanoacetate with nitromethane or nitroethane in ethanol at room temperature. There have been no reports of nickel zinc ferrite being used as a catalyst. The catalyst was specified by using several techniques, including DSC–TGA, FT-IR, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), BET, and scanning electron microscope (SEM). The present protocol suggests some benefits, which include green reaction conditions, simple reaction work-up, short reaction time, excellent product yields, chromatography-free purification, and high efficiency of the heterogeneous catalyst. More importantly, this catalyst was recovered from the reaction mixture using a simple external magnet, and it was reused successively at least seven times without any significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

Catalysts are the jewel in the crown of the chemical industry, accelerating reaction kinetics and augmenting the efficiency of desired reaction paths. Natural feedstock is a renewable resource capable of providing valuable functional products; in addition, it confers an opportunity to create catalysts. As an alternative to stoichiometric reagents, and as a part of a sustainable approach, the implications of using natural feedstocks as a source of new catalysts has attracted considerable interest. Natural feedstock-derived catalysts can promote chemical transformations more efficiently. Recent reports have highlighted the significant role of these biogenic, cost-effective, innocuous, biodegradable materials as catalysts in many biologically and pharmacologically important protocols. This review outlines the decisive organic transformations for which feedstock-derived catalysts have been employed effectively and successfully, along with their economic and environmental benefits over traditional catalytic systems. [ABSTRACT FROM AUTHOR]

Tn5 mutagenesis of the pHK120 clone is used to study the production of Phaseolotoxin Ndelta(N'-sulfo-diaminophosphinyl)-ornithyl-alanyl-homoarganine. The pHK120 clone insert contains at least five Tn5 mutants which may be located in different chromosomal fragments. Phaseolotoxin inhibits the enzyme ornithine carbomoyltransferase which leads to growth inhibitors in plants and is produced by Pseudomonas syringae pv. phaseolicola.

A clean and highly efficient protocol for green synthesis of bis(indole)methanes and bis(pyrazolyl)methanes has been successfully achieved by using a naturally sourced bio-surfactant, chickpea leaf exudates (CLE), as a Brønsted acid-type catalyst. The reaction proceeds smoothly with CLE in alcoholic medium at 60 °C in a very short reaction time, and therefore it is a green, environmentally sound alternative to the existing protocols. In comparison to the reported conventional methods, this synthetic pathway complies with several key requirements of green chemistry principles such as avoiding the use of any toxic/hazardous catalyst and additives/promoters, the use of a biodegradable catalyst obtained from renewable resources, auxiliary solvent conditions, and reusability of the catalyst. Thus, the reported protocol offers an attractive option because of its ecological safety, straightforward work-up procedure and excellent values of green chemistry metrics as compared with other reported methods. [ABSTRACT FROM AUTHOR]

Synthesis of 2-amino I 4H,5H i -pyrano[3,2 I c i ]chromene derivatives.a [3] HT

A novel –SO3H difunctionalized Bronsted acidic ionic liquid (BAIL) 1, 5-bis (butanesulphonic acid)-diazobicyclo [4,3,0] non-5-enium hydrogen sulphate [BBSA-DBN][HSO4] is introduced for efficient synthesis of quinoxalines via condensation of substituted 1,2-diketones and various aromatic 1,2-diamines. It could serve as a dual functional catalyst for these reactions. This method has the advantages of mild reaction conditions, high yields, short reaction times, easy work-up, non-chromatographic separations and being environmentally friendly. This protocol provides an effective and environmentally friendly alternative methodology for production of quinoxalines and extends the chemical utilization of benzil in organic synthesis. This room-temperature-derived ionic liquid is highly acidic due to presence of two –SO3H groups and two HSO4− anions. Moreover, the IL [BBSA-DBN][HSO4] could be easily recovered and reused at least five times without change in its catalytic activity. The formation of IL [BBSA-DBN][HSO4] was confirmed by 1H, 13C NMR spectroscopic techniques. [ABSTRACT FROM AUTHOR]

The present study is an attempt to assess the silkworm cocoon production and its profitability in North Eastern Karnataka region through structured survey during 2017-18. The per acre total investment required for establishment of mulberry garden was ₹ 44,150. However, establishment cost varies across the districts of study area. The human labour usage in establishment of mulberry garden was highest in Kalaburagi (53.25 mandays) district compared to Raichur (50.30 mandays) and Ballari (46.80 mandays) districts. The variable cost incurred by sericulture farmers was more than 81 per cent of the total cost of cultivation of mulberry. However, the expenditure on human labour (35.97%) was the major constituent of the total cost. The variable cost incurred in silk cocoon production was found to be more than 90 per cent of the total cost of cocoon production. Expenditure on mulberry leaves (54.96%) was the major constituent of total variable cost. However, human labour and marketing cost were the other major cost components of the total cost. The net returns realised by silk cocoon producing farmers was ₹ 55,819 per 300 DFLs. The extent of net returns realised was highest in Kalaburagi (₹ 58,708/ 300 DFLs) district compared to Raichur (₹ 54,726) and Ballari (₹ 54,025) districts. [ABSTRACT FROM AUTHOR]

An external base‐free, efficient, cost‐effective, and environmentally benign protocol has been developed for the one‐pot multicomponent synthesis of highly functionalized pyranopyrazoles and benzochromenes using water extract of Agave americana (century plant) leaf ash, a waste‐derived catalyst, at room temperature. Mild reaction conditions, high yield, easy isolation of products, eco‐friendly standards, and no chromatographic separation are the salient features of this protocol. [ABSTRACT FROM AUTHOR]

Rice occupies a pivotal place in Indian agriculture and it contributes about 13 per cent of annual agriculture GDP and provides 43 per cent calorie requirement for more than 70 per cent of Indian population. This study was conducted in Thungabhadra area of Karnataka and it is also called as 'Rice Bowl of Karnataka', since it occupies nearly 65 per cent of total (3.63 lakh ha) area of paddy in Karnataka. In this area, paddy-paddy system is the predominant cropping system. Paddy crop residues include any biomass left in the field after grains and other economic components have been harvested. Crop residues are also a principal source of carbon, which constitutes about 40 per cent of the total biomass on dry weight basis. Crop residues were considered as precious commodity because it can be used as a feed for the fodder and mulching for various crops and must never be considered as waste. The paddy residues are typically burnt on-farm across different regions of this area. The problem is more severe in the head and mid region of this area, particularly in the mechanized harvesting in paddy-paddy cropping system. There are four methods of residue management practices, these are as removal of straw and burning of stubble, burning of straw and stubble, removal of straw and incorporation of stubble and incorporation of straw and stubble among, which removal of straw and burning of stubble (42.45 %) is the major one. The main reasons for burning of residues are low cost and labour scarcity. Total cost of cultivation of paddy per acre was found to be marginally lower burning of straw and stubbles method as compared (... 38411/acre) to incorporating straw and stubbles (... 41845/acre) method. [ABSTRACT FROM AUTHOR]

The study was attempted to measure the economic performance of cooperative sugar factories in terms of total costs and returns, capacity utilization, physical and financial indicators and ratio analysis of the factories. In this study the three cooperative sugar factories are taken into consideration and the Compound Annual Growth Rate (CAGR) for all the physical and financial indicators are worked out wherein the results suggested that a significant variation in the total cost and returns, capacity utilization and both physical and financial indicators over years within the three sugar factories was found. Further, the study revealed enough evidence about the financial ratios, which in turn showed the economic potentiality of the respective sugar factories. For the better performance of the factories an efficient planning and automation well before the start of the season is necessary and the government should come forward to help the farmers in making the cane bill payment at an early stage by the factories, by extending the financial assistance. [ABSTRACT FROM AUTHOR]