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Being an important constituent of naturally occurring heterocyclic compounds with a myriad of interesting biological activities, the furocoumarin motif has claimed vast interest in synthetic and medicinal research. Designing organic synthesis following a green and sustainable approach finds special importance in terms of energy efficiency, and cost‐effectiveness and hence becoming an important domain of research in the recent past. The methodologies for the sustainable synthesis of furocoumarin presented here particularly include the strategies developed under microwave irradiation, solvent‐free conditions or uses of green solvent, metal‐free routes, room temperature mediated and following one‐pot MCR reactions. This review article attempts to highlight the recent advances in the sustainable synthesis of furocoumarins along with general aspects like natural occurrence, and biological activities of this particular heterocyclic scaffold. [ABSTRACT FROM AUTHOR]

The primary source of soil pollution is a complex mixture of numerous inorganic and organic compounds (including chlorinated compounds, nutrients, and heavy metals, etc.). The presence of all of these compounds makes remediation and cleanup difficult. In this study, the phytoremediation ability of Jatropha curcas and Pongamia pinnata was tested to remove nickel (Ni) and Zinc (Zn) from paper mill and municipal landfill contaminated soils, to understand the uptake potential and to estimate the accumulation pattern of Ni and Zn in the vegetative parts of the plant. The experiments were carried out in pots (3 kg capacity) and the different combinations of soil were made by mixing the contaminated soil with a reference soil (forest soil) as T 0 , T 25 , T 50 , T 75 and T 100. The plant biomass, chlorophyll content, proline, nitrate reductase activity and metal removal efficiency (%)were determined after 120 DAS (i.e., the days after sowing). The results of the study showed that with increasing metal stress, there is a reduction in the above-ground biomass content in both the plant species with a slightly less impact on the root biomass. Over a period of 4 months, J. curcas and P. pinnata removed 82–86% and 93-90% Ni, respectively. The removal of Zn was significantly less as compared to Ni as most of the Zn remained in the belowground part (roots) and in the soil. Besides, the phytostabilization capacities of the plants were calculated on the basis of their tolerance index (TI), bioaccumulation factor (BAF) and translocation factor (TF). The low BAF and TF values with increasing heavy metals (HMs) content indicates its higher phytostabilization capacity in the root and rhizospheric region as compared to phytoaccumulation. [Display omitted] • J. curcas and P. pinnata removes 82 - 86 % and 93- 90 % Ni respectively. • High biomass and bioaccumulation factor (BAF) > 1: Suitable for metal phytoextraction. • Low biomass and BAF < 1: Suitable for metal phytostabilization. • Low translocation factor (< 1) indicated the phytostabilization capacity of the plants. [ABSTRACT FROM AUTHOR]

Assam is a melting pot of various communities with their own cultural tradition and nature-linked practices. The Phakeyals, or the Tai Phakes, believed to be an offshoot of the great Tai race, which entered Assam in the latter half of the 18th century, now inhabiting in Dibrugarh and Tinsukia districts of the state, are attributed with a sound indigenous knowledge of environment and practices based on it. They resort to a number of herbal treatments or folk medicines, which are collected from the environment. This paperaims at examining the beliefs and rituals prevalent among the Phakeyals of the Barphake Village of Tinsukia district that have helped in conserving nature by judicious use of bio-resources and maintaining the ecological balance in nature. [ABSTRACT FROM AUTHOR]

Crop residue burning is a major environmental issue and their potential long-term impact on the climate is a global concern. A laboratory experiment was carried out to study the impact of biochar on carbon loss from tropical soils. Residues of two important foodgrain crops viz, rice and wheat were used to prepare respective biochar and added as amendments in two different tropical agricultural soils (red and alluvial). In general carbon loss was more from alluvial soil than red soil. In alluvial soil, carbon loss was more when biochars were applied along with N fertilizer (urea) than biochar alone. Increasing rate of application of rice biochar without urea showed potential carbon protection in alluvial soil. Interestingly, unlike rest of the treatments, carbon loss was more in red soil when wheat biochar was applied without urea than with it. While physicochemical characteristics of biochars play crucial role in carbon protection, the intrinsic nature and properties of soil largely regulates it. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 183-188, 2016 [ABSTRACT FROM AUTHOR]

Some novel 5-aminoalkylbarbituric acids and corresponding chromene derivatives were synthesized via a one-pot, three-component Mannich reaction starting from 1,3-dimethylbarbituric acid, arylaldehydes, and amines. [ABSTRACT FROM PUBLISHER]

Some dihydrofuro-fused coumarin derivatives were synthesized from 3-aminoalkyl-4-hydroxycoumarin via in situ generation ofN-ylide. The 3-aminoalkylated 4-hydroxycoumarin derivatives were synthesized from one-pot, three-component reaction of 4-hydroxycoumarin, aryl aldehydes, and secondary amines in ethanol at room temperature. Again, when salicylaldehyde was employed instead of benzaldehyde, interestingly pyranocoumarins were obtained. The reaction protocol can be further explored toward the synthesis of many other heterocyclic fused dihydrofurans. [ABSTRACT FROM AUTHOR]

Drying conditions for X anthosoma sagittifolium tubers were optimized using response surface methodology. A face-centered central composite design with two numerical factors and one categorical factor was selected for conducting the experiments. The numerical factors selected were air temperature from 50 to 70C, and drying time from 4 to 8 h while shape of the cut tubers i.e., slices or cubes was the categorical factor. The responses investigated were water loss, final moisture content, rehydration coefficient and peak viscosity. The study revealed that the effect of all the factors was significant on the responses. The optimum condition obtained using the desirability function for achieving the desired product was found at the temperature of 68.57C and the drying time of 5.51 h for slices. The values of moisture content, water loss, rehydration coefficient and peak viscosity at the optimum drying condition were 0.43% dry basis, 68.55 g/100 g sample, 0.84 and 4039.4 cP, respectively. Practical Applications The tubers of X anthosoma contain reasonable amounts of calcium, phosphorus, and vitamins A and B. The starch present in X anthosoma tubers is easily digestible because of its small granule size. The protein and dietary fiber content of the edible portion is also high as compared with other root and tuber crops. It can be used in the preparation of baby foods and diets of people allergic to cereal proteins. Although the production of X anthosoma sagittifolium is high worldwide and has the potential of meeting the energy requirements of the consumer because of its high starch content and better starch quality, there are very few studies related to drying of X . sagittifolium tubers to increase the shelf life of the product. Therefore, the present study becomes important as proper understanding of the drying process of X anthosoma tubers is necessary for the process to become industrially feasible. [ABSTRACT FROM AUTHOR]

The city of Guwahati has a rich historical past and finds frequent mention in medieval historical sources and epics. From the pre-historic existence, the city has evolved through various stages of development and lately, the city has entered a phase of vigorous growth changing remarkably its fabric of settlement and the overall morphology of the urban landscape. Throughout the history of growth and development of Guwahati city, the river Brahmaputra has played the most important role in shaping the socio-economic life of its dwellers and the land use pattern of the city. The river still continues to play a unique role in maintaining the city's scenic beauty, grandeur, health and prosperity. In fact the nourishing presence of the river in the heart of the city provides a variety of facilities and opportunities to the city dwellers, some of which are, however, directly visible, while many others need careful observation for assessing their contribution. Of late, this eco-city has also been witnessing a severe demographic hazard because of migration of people from other parts of Assam and the Northeast as place of opportunity. The growing urban congestion and extension of human settlement, roads and other constructions to the marginal and delicate areas like the hill slopes, fringes of the beels, wetlands and rivulets have now made the city's drainage highly complicated and increasingly inefficient. These have caused some severe problems such as killer landslide, erosion, water logging and flash flood. [ABSTRACT FROM AUTHOR]

This study reports the environmental fate and ecological hazard of the three heavy metals (HMs), viz. copper (Cu), manganese (Mn) and zinc (Zn) in soil influenced by municipal solid waste (MSW) dumping. The experimental site is situated in the vicinity of Deepor Beel, a Ramsar site located in Guwahati, India. This study assessed (i) the distribution pattern of Cu, Mn and Zn in six geochemical fractionations; (ii) the mobility, bioavailability and toxicity of Cu, Mn and Zn based on eight contamination and ecological indices, and (iii) the impact of Cu, Mn and Zn on soil quality. Altogether, 18 soil samples were collected and analysed from the study site using stratified random sampling. Pollution indices and multivariate statistics were applied on the data to identify the level and source of analysed HMs. Sequential extraction has revealed that the binding strength of Cu, Mn and Zn had a uniform trend. Mobility and potential bioavailability of studied HMs were in the order Mn > Cu > Zn. Analysed HMs were dominantly associated with non-bioavailable fractions. The observed low values of various contamination factors indicated the lesser contamination load posed by these metals. Conversely, their high enrichment factor and geo-accumulation index values indicated the sources of these metals were anthropogenic. Overall, the pollution and ecological indices registered lower contamination. Yet, it would be prudent to adopt efficient MSW management strategies for eliminating any future risk emanating out of this dumping site and posing threat to nearby Deepor Beel and its associated flora and fauna. Image 1 • Environmental risks associated with three heavy metals (Cu, Mn and Zn) in the soils were determined. • Municipal solid wastes (MSW) containing heavy metals (HM) pose ecological risk. • Major sources of these HMs were anthropogenic in nature. • Scientific waste management is needed to protect Deepor Beel, a Ramsar site. [ABSTRACT FROM AUTHOR]

The transformation follows an initial iodine-catalyzed reaction of 4-hydroxycoumarins with carbonyl compounds to biscoumarins followed by lactone ring opening, cyclization, and oxidative aromatization. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the chemical formula for the derivatives of barbituric acid, and the synthesis and function of annulated barbituric acids.

Earthworms are known to bio-degrade various types of organic materials added or already present in soil. Two soils were collected from different land use patterns viz. an agricultural land (AL) and an undisturbed land (UL) of a mountain ecosystem of State of Himachal Pradesh in India for the present investigation. A laboratory microcosm study was carried out to elucidate effects of various agricultural-soil amendments, viz. wood ash (WA), rice husk (RH), cow dung (CW) and their mixture (MA) applied @25 t ha −1 , on selective biological and chemical properties of earthworm ( Eisenia fetida ) casts and growth in the collected soils. Subsequently, earthworms were reared in soils from both AL & UL, treated with the amendments; and the resultant earthworm cast (E w C) properties were found to be largely determined by the nature of amendments rather than land use types. Soils treated with MA produced casts displayed higher nutrient content, microbial biomass C with higher activities of dehydrogenase and urease. Earthworm growth and cast formation were greater in the soil from UL over soil from AL for all treatments except WA, implying better acclimatization and earthworm activity in the former. Further, casts produced under UL had higher nutrient mobilization and enzyme activity in comparison to AL. Results suggested that agricultural intervention in an undisturbed land might weaken its ability to support growth, development in conjunction with the activities of earthworms and associated enzymes. [ABSTRACT FROM AUTHOR]