λ-cyhalothrin and cypermethrin induced in vivo alterations in the activity of acetylcholinesterase in a freshwater fish, Channa punctatus (Bloch)

In the present study, the in vivo effects of λ-cyhalothrin and cypermethrin on the activity of acetylcholinesterase (AChE, EC 3.1.1.7) were evaluated for 96 h in brain, muscle and gills of Channa punctatus. Both compounds exhibited tissue specific as well as dose dependent decrease in the activity of AChE. The treated fish showed a significant decrease in the activity of AChE in brain and a lesser inhibition in muscle and gills in response to the increasing concentrations of λ-cyhalothrin as well as cypermethrin. Our results indicated that the brain was the main target organ for both insecticides, followed by muscle and gills, as determined by AChE inhibition study. However, these organs showed variations in the degree of AChE inhibition for separate treatments of both insecticides. The λ-cyhalothrin was a more potent AChE inhibitor as compared to cypermethrin. These findings indicated that apart from the established mechanism of delayed closure of sodium ion channels, these pyrethroids inhibit the activity of AChE in C. punctatus which could further aggravate their neurotoxic effects.     

Alkaloids as potential anti-tubercular agents

An increasing incidence of deaths due to tuberculosis and the known drawbacks of the current existing drugs including the emergence of multi drug-resistant strains have led to a renewed interest in the discovery of new anti-tubercular agents with novel modes of actions. The recent researches focused on natural products have shown a useful way to obtain a potentially rich source of drug candidates, where alkaloids have been found more effective. The present review focuses on current epidemiology of tuberculosis, synergy of the disease with HIV, current therapy, available molecular targets and, highlights why natural products especially alkaloids are so important. The review summarizes alkaloids found active against mycobacteria from the mid-1980s to late 2008 with special attention on the study of structure–activity relationship (SAR).     

A transgenic RNAi approach for developing tomato plants immune to Pepino mosaic virus

RNA interference (RNAi) or gene silencing is a natural defence response of plants to invading viruses. Here, we applied this approach against pepino mosaic virus (PepMV) isolates in their natural host, tomato. PepMV isolates differ in their genetic sequences, the severity of the disease they induce, and their worldwide distribution. PepMV causes heavy crop losses, mainly due to impaired tomato fruit quality. Resistant varieties are not yet available, despite many years of resistance breeding efforts within the tomato seed industry. To generate broad resistance to PepMV strains, conserved sequences from three different strains of PepMV (US1, LP, and CH2) were synthesized as a single insert and cloned in a hairpin configuration into a binary vector, which was used to transform tomato plants. Transgenic tomato lines that expressed a high level of transgene-siRNA exhibited immunity to PepMV strains, including a new Israeli isolate. This immunity was maintained even after graft inoculation, in which a transgenic scion was grafted onto nontransgenic infected rootstocks. However, an immune transgenic rootstock was unable to induce resistance in a nontransformed scion. These results provide the first example of engineered immunity to diverse PepMV strains in transgenic tomato based on gene silencing.     

Potential Use of Hibiscus Rosa-Sinensis Leaf Extract for the Destabilization of Turbid Water

In the present study, the ability of Hibiscus rosa-sinensis leaf extract (HLE) to act as a natural coagulant for the water treatment was tested. Synthetic turbid solutions were prepared using kaolinite, and the efficiency of HLE was examined for low and high turbid solutions. HLE was very effective in high turbid solutions than in low turbid water and follows enmeshment mechanism of destabilization. An insignificant effect of alkalinity on the performance of HLE was observed. The addition of NaCl increased the dissolution of coagulation active species and enhanced the efficiency of HLE, significantly. Hydroxyl and carboxyl groups present in HLE were the major functional groups responsible for the bonding between coagulant and kaolinite. The efficiency of alum was very high compared to that of HLE in both turbid solutions. But the optimal dosages of HLE were lesser than that of alum. Thus, HLE can be used as a coagulant aid for the effective treatment of water.     

Removal of Trinitrotoluene with Nano Zerovalent Iron Impregnated Graphene Oxide

Nano zerovalent iron (nZVI) impregnated reduced graphene oxide (nZVI-rGO) hybrid was prepared via gaseous hydrogen reduction of anhydrous iron(III) chloride (FeCl₃) on the surface of thermally exfoliated reduced graphene oxide (rGO) nanosheets without using any toxic reducing agent, surfactant, or stabilizing agent. Characterization of prepared samples was carried out using various techniques. Morphological study showed that prepared rGO possesses a few-layered wrinkled paper-like structures and nZVI particles of ~?30 nm size were homogeneously dispersed on the surface of rGO nanosheets. Fourier transform infrared (FTIR), X-ray diffraction (XRD), and energy dispersive X-ray spectrometry (EDS) analyses indicated that oxygen-containing functional groups decreased in the order of graphite oxide (GO) > rGO > nZVI-rGO. Removal studies of trinitrotoluene (TNT) were carried out using graphite (G), GO, rGO, and nZVI-rGO with the aid of high-performance liquid chromatography (HPLC). Kinetic models were applied to establish the rate and mechanism of adsorption of TNT on different adsorbents, and intraparticle diffusion model based on initial adsorption characteristics was employed to ascertain mechanism of film and intraparticle diffusion in the adsorption process. The removal rate and adsorption capacity was found to be highest for nZVI-rGO, which renders this adsorbent to be a potential futuristic adsorbent for removal of explosives.

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Use of resistant ACCase mutants to screen for novel inhibitors against resistant and susceptible forms of ACCase from grass weeds

The aryloxyphenoxypropionic acid (AOPP) and cyclohexanedione (CHD) herbicides inhibit the first committed enzyme in fatty acid biosynthesis, acetyl CoA carboxylase (ACCase). The frequent use of AOPP and CHD herbicides has resulted in the development of resistance to these herbicides in many grass weed species. New herbicides that inhibit both the susceptible and resistant forms of ACCase in grass weeds would have obvious commercial appeal. In the present study, an attempt was made to identify molecules that target both the herbicide-sensitive and -resistant forms of ACCase. Seven experimental compounds, either CHD-like or AOPP-CHD hybrids, were synthesized and assayed against previously characterized susceptible and resistant forms of ACCase. All seven compounds inhibited ACCase from sensitive biotypes of Setaria viridis and Eleusine indica (I50 values from 6.4 to >100 microM) but were not particularly potent compared to some commercialized herbicides (I50 values of 0.08-5.6 microM). In almost all cases, the I50 values for each compound assayed against the resistant ACCases were higher than those against the corresponding sensitive ACCase, indicating reduced binding to the resistant ACCases. One compound, a CHD analogue, was almost equally effective against the resistant and susceptible ACCases, although it was not a very potent ACCase inhibitor per se (I50 of 51 and 76 microM against susceptible ACCase from S. viridis and E. indica, respectively). The AOPP-CHD hybrid molecules also inhibited some of the resistant ACCases, with I50 values ranging from 6.4 to 50 microM. These compounds may be good leads for developing ACCase inhibitors that target a wider range of ACCase isoforms, including those found in AOPP- and CHD-resistant weed biotypes.     

Evaluation of Groundnut Genotypes for Tolerance to Phosphorus Deficiency

Phosphorous (P) is one of the most deficient nutrients owing to its fixation and low mobility in acid soils. A total of 324 genotypes were screened in both P sufficient and insufficient conditions to evaluate the P uptake efficiency. Thirty-four responsive genotypes were evaluated in solution culture with two checks, ICGV 86590 and JL 24. The components of variability revealed high magnitude and highly heritable nature of the variation. Highly responsive genotypes to P insufficiency; ICG 14475, ICGV 92188, and M 68 were further tested for phosphorus uptake efficiency at 15, 30, and 45 days after sowing (DAS) along with checks in sand culture in pots. ICG 14475, ICGV 92188, and ICGV 86590 were found superior in both acquisition and utilization of phosphorus due to enhanced root production for P exploration and shoot expansion, respectively. JL 24 was poor in acquisition due to lack of response in root traits under P insufficiency.     

Laboratory Yields and Process Stream Compositions from E‐Mill and Dry‐Grind Corn Processes Using a Granular Starch Hydrolyzing Enzyme

In dry‐grind corn processing, the whole kernel is fermented to produce ethanol and distillers dried grains with solubles (DDGS); the E‐Mill process was developed to generate coproducts in addition to DDGS. Compositions of thin stillage and wet grains obtained from the E‐Mill process will be different from the dry‐grind process. Knowledge of thin stillage compositions will provide information to improve coproducts from both processes. Laboratory dry‐grind and E‐Mill processes that used granular starch hydrolyzing enzymes (GSHE) were compared and process yields determined. Two methods, centrifugation and screening, were used to produce thin stillage and wet grains from the laboratory processes. Compositions of process streams were determined. In the dry‐grind process using GSHE, solids contents of beer, whole stillage, and wet grains were higher compared to the same fractions from the E‐Mill process using GSHE. Solids contents of mash for both processes were similar. Total solids, soluble solids, and ash contents of thin stillage were similar for the two processes. Fat content of thin stillage from E‐Mill was lower than that from the dry‐grind process; protein content of E‐Mill thin stillage was higher than that from dry‐grind thin stillage. Removal of germ and fiber before fermentation changed composition of thin stillage from the E‐Mill process. The screening method produced higher thin stillage and lower wet grains yields than using a centrifugation method. The screening method was less time consuming but resulted in limited wet grains material for additional analyses or processing. The centrifugation method of thin stillage separation removed more solids from thin stillage than the screening method.     

Landraces-potential treasure for sustainable wheat improvement

Genetic Resources and Crop Evolution - Agricultural production is facing serious threat from various biotic and abiotic stresses specifically under climatic challenges. It is becoming increasingly...