Purification and partial characterization of GtHs (cfLH and cfFSH) from Indian walking catfish (Clarias batrachus) (L.) and development of a homologous ELISA for cfLH     

Shrabanti Sarkar  Panchanan Nath 《Aquaculture Research》2012,43(6):879-896

Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL^?1 (1.25 ng well^?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.  相似文献   

Carbondioxide gating in silk cocoon     

M Roy  SK Meena  TS Kusurkar  SK Singh  NK Sethy  K Bhargava  S Sarkar  M Das 《Biointerphases》2012,7(1-4):45

Silk is the generic name given to the fibrous proteins spun by a number of arthropods. During metamorphosis, the larva of the silk producing arthropods excrete silk-fiber from its mouth and spun it around the body to form a protective structure called cocoon. An adult moth emerges out from the cocoon after the dormant phase (pupal phase) varying from 2 weeks to 9 months. It is intriguing how CO(2)/O(2) and ambient temperature are regulated inside the cocoon during the development of the pupa. Here we show that the cocoon membrane is asymmetric, it allows preferential gating of CO(2) from inside to outside and it regulates a physiological temperature inside the cocoon irrespective of the surrounding environment temperature. We demonstrate that under simulating CO(2) rich external environment, the CO(2) does not diffuse inside the cocoon. Whereas, when CO(2) was injected inside the cocoon, it diffuses out in 20 s, indicating gating of CO(2) from inside to outside the membrane. Removal of the calcium oxalate hydrate crystals which are naturally present on the outer surface of the cocoon affected the complete blockade of CO(2) flow from outside to inside suggesting its role to trap most of the CO(2) as hydrogen bonded bicarbonate on the surface. The weaved silk of the cocoon worked as the second barrier to prevent residual CO(2) passage. Furthermore, we show that under two extreme natural temperature regime of 5 and 50 °C, a temperature of 25 and 34 °C respectively were maintained inside the cocoons. Our results demonstrate, how CO(2) gating and thermoregulation helps in maintaining an ambient atmosphere inside the cocoon for the growth of pupa. Such natural architectural control of gas and temperature regulation could be helpful in developing energy saving structures and gas filters.  相似文献   

Growth and enzymatic activity of maize (Zea mays L.) plant: Solution culture test for copper dioxide nano particles     

Tapan Adhikari  Dipayan Sarkar  Hamid Mashayekhi  Baoshan Xing 《Journal of plant nutrition》2016,39(1):99-115

Copper (Cu) is an essential micronutrient for plants, which acts either as the metal component of enzymes or as a functional structural or a regulatory co-factor of a large number of enzymes. To understand the possible benefits of applying nanotechnology to agriculture, the first step should be to analyze penetration and transport of nano-particles in plants. The present study was conducted to test the hypothesis that copper nanoparticle would enter into the plant cell and govern the growth of maize plant.A solution culture experiment was conducted to investigate the effect of Cu nano-particles (<50nm) on the growth and enzymatic activity of maize (Zea mays L.) plant. Bioaccumulation of Cu nano-particles in plant was also investigated. Results showed that Cu nano-particles can enter into the plant cell through roots and leaves. Bioaccumulation increased with increasing concentration of Cu nano-particles (NPs), and agglomeration of particles was observed in the cells using transmission-electron microscopy. Application of Cu nano-particles through solution culture as well as spray enhanced the growth (51%) of maize plant in comparison to control. The different enzymatic activities like glucose-6-phosphate dehydrogenase, succinate dehydrogenase, superoxide dismutase, catalase, andguaiacol peroxidase were studied to find a possible pathway through which NPs may affect the enzymatic activity of plant. Amongst the enzymes, the activity of glucose-6-phosphate dehydrogenase was highly influenced by copper oxide (CuO)nano-particles application by spray as well as in solution. Experimental results revealed that CuOnano-particles affected the pentose phosphate pathway of maize plant. The obtained experimental results provided conclusive evidence to indicate that the nano-particles considered under this study could enter into the plant cell, easily be assimilated by plants and also enhanced its growth by regulating the different enzyme activities.  相似文献   

Synthesis of poly(hydroxamic acid) ligand from polymer grafted khaya cellulose for transition metals extraction     

Md Lutfor Rahman  Bablu Hira Mandal  Shaheen M. Sarkar  Nor Asiken Abdul Wahab  Mashitah Mohd Yusoff  Sazmal E. Arshad  Baba Musta 《Fibers and Polymers》2016,17(4):521-532

A cellulose-graft-poly(methyl acrylate) was synthesized by free radical initiating process and the ester functional groups were converted into the hydroxamic acid ligand. The intermediate and final products are characterized by FT-IR, FE-SEM, HR-TEM and XPS technique. The pH of the solution acts as a key factor in achieving optical color signals of metalcomplexation. The reflectance spectra of the [Cu-ligand]n+ complex was found to be a highest absorbance at 99.8 % at pH 6 and it was increased upon increasing of Cu²⁺ ion concentrations and a broad peak at 700 nm was observed which indicated the charge transfer (π-π transition) metals-Cu complex. The adsorption capacity of copper was found to be superior (336 mg g^?1) rather than other transition metals such as Fe³⁺, Co³⁺, Cr³⁺, Ni²⁺, Mn²⁺ and Zn²⁺ were 310, 295, 288, 250, 248 and 225 mg g^-1, respectively at pH 6. The experimental data of all metal ions fitted significantly with the pseudo-second-order rate equation. The transition metal ions sorption onto ligand were well fitted with the Langmuir isotherm model (R²>0.99), which suggested that the cellulose-based adsorbent known as poly(hydroxamic acid) ligand surface is homogenous and monolayer. The reusability of the poly(hydroxamic acid) ligand was checked by the sorption/desorption process up to ten cycles without any significant loss in its original sensing and removal performances.  相似文献   

Relation of soya bean meal level to the concentration of plasma free amino acids and body growth in white rats     

Mandal TK  Parvin N  Mondal S  Saxena V  Saxena AK  Sarkar S  Saha M 《Journal of animal physiology and animal nutrition》2012,96(2):191-197

Amino acid (AA) levels in plasma and body growth were determined in rats (n20) fed diets with different soya bean meal levels. Free AA in plasma was determined by reversed-phase high-pressure liquid chromatography. We have used four levels of protein diets like 8%, 15%, 23% and 35% in this trial. Rats which were fed the low-protein (8%) diet with low percentage of soya bean meal were found to be growth-retarded. The body weight gain of high protein group (35%) was lower than that of the 23% groups. In the rats fed with the low-soya bean meal diet, some nonessential AA (NEAA) in plasma like asparagine, aspartic acid, cysteine, glutamic acid and serine increased, whereas the essential AA (EAA), with the exception of arginine, methionine and valine decreased. Here, plasma EAA-to-NEAA ratios were not correlated to growth and experimental diet. We hypothesize that AA metabolism is associated to changes in growth in rats on different protein intake. This study has showed the sensitivity of body mass gain, feed intake, feed conversion rate of rats to four levels of protein in the diet under controlled experimental conditions.  相似文献   

Management practices of macronutrients for potato for smallholder farming system at alluvial soil (Entisols) of India     

Lalita Rana  Sudarshan Kumar Dutta  Krishnendu Ray  Kaushik Majumdar  Sukamal Sarkar 《Archives of Agronomy and Soil Science》2017,63(14):1963-1976

In the present study, seven fertilizer treatments [T₁, 50% NPK; T₂, 100% NPK (Recommended dose of fertilizer, 200–65.4–124.5 kg N-P-K ha^?1); T₃, 150% NPK; T₄, 100% PK; T₅, 100% NK; T₆, 100% NP and T₇, control (zero NPK)] with four replications were assessed in the new alluvial soil zone (Entisols) of West Bengal, India. The objectives of the study were to generate information on potato productivity, profitability, indigenous nutrient supply and net gain/loss of NPK in post-harvest soil. Plants grown under higher NPK supply resulted in higher tuber yield and there were significant (p ≤ 0.05) reductions in total yield with nutrient omissions. Nutrient?limited yields were 19.78, 2.83 and 1.77 t ha^?1 for N, P and K, considering total tuber yield (28.24 t ha^?1) obtained under 100% NPK as targeted yield. Indigenous nutrient supply of N, P and K were estimated at 24.1, 22.34 and 110.22 kg ha^?1, respectively that indicates higher K?supplying capacity of experimental soil as compared to N and P. Net income (US$1349 ha^?1 year^?1) and B:C ratio (1.91) was highest with 100% NPK, and further addition of NPK (150%) resulted in decrease on net return (US$1193 ha^?1 year^?1) and B:C ratio (1.73).  相似文献   

Combination of different marine algal extracts as biostimulant and biofungicide     

Gargi Sarkar  Niharika Jatar  Pranami Goswami  Richa Cyriac  K. Suthindhiran 《Journal of plant nutrition》2018,41(9):1163-1171

This study investigates the efficiency of seaweed liquid fertilizer (SLF) prepared from combinations of different seaweeds (Sargassum polyphyllum, Turbinaria ornata, Gelidiopsis sp., Padina tetrastomatica, Gracilaria corticata) as a stimulant for the growth of Vigna radiata (Mung) as well as its antagonistic activity against fungal pathogens (Alternaria solani, Rhizoctonia solani., Sarocladium oryzae). 100% SLF was prepared, which was further diluted to 60%, 40%, and 20%. Seeds were soaked in four different concentrations of the SLF (20%, 40%, 60%, and 100%) for 12 hr and planted. After 60 d, the root and shoot length were increased by 14% and 16%, respectively, with SLF (100%). The carbohydrate and protein concentrations were also increased by 70% and 86%, respectively, at 100% SLF. The concentration of chlorophyll a, chlorophyll b, and carotenoids were found to be increased by 20%, 43%, and 28%, respectively, with 100% SLF. Further, the SLF (60% and 100%) successfully inhibited the growth of fungal pathogen A. solani but the other tested strains were found to be resistant. The present study indicates that 100% SLF concentration acts as both biostimulant and biofungicide for A. solani and thus, this SLF could be used as a potential alternative to the chemical fertilizers.  相似文献   

Boron fertilization effects in processing grade potato on an Inceptisol of West Bengal,India     

Sukamal Sarkar  Krishnendu Ray  Dibakar Ghosh 《Journal of plant nutrition》2018,41(11):1456-1470

A 2-year field trial was conducted in processing grade potato cv. Kufri Chipsona-3. The treatments comprised recommended dose of fertilizer (RDF) (200:150:150 N:P₂O₅:K₂O kg ha^?1) with or without boron (B) application (soil and foliar). The results revealed that B fertilization significantly increased tuber number and yield. Three sprays of 0.1% boric acid (at 40, 50 and 60 days after planting) produced the maximum number and yield of tubers and enhanced B uptake in potato tuber, haulm as well as in total plant accounting 85.8, 182.0 and 169.8% more than control, respectively. The same treatment came up with greatest net return and benefit: cost ratio. B fertilization exerted significant influence on available N and B status of post-harvest soil, while the effect was non-significant on available P and K. Results suggest that right dose and method of B application is vital for optimizing tuber yield and B-use efficiency for processing grade potato.  相似文献   

Co-Composting Urban Waste,Plant Residues,and Rock Phosphate: Biochemical Characterization and Evaluation of Compost Maturity     

U. A. Naher  M. I. U. Sarkar  A. Jahan  J. C. Biswas 《Communications in Soil Science and Plant Analysis》2018,49(6):751-762

Co-composting of urban wastes (UWs) and plant residues with rock phosphate (RP) produces quality compost and reduces the use of chemical phosphorus fertilizer. Biochemical process of three compost piles (P): P₁- 50% UW + 30% rice straw (RS) + 10% sawdust (SD) + 8% RP + 2% sugarcane trash (ST), P₂- 50% UW + 23% RS + 10% SD + 15% mustard oil cake + 2% ST, and P₃- 95% UW + 5% RP was studied. Decomposition rate followed first-order kinetics and maximum (77%) was in P₃. The highest bacterial population was found in P₂ having higher cumulative CO₂ evolution (53.76 mg CO₂ g^?1 volume solid). Prevalence of phosphate-solubilizing bacteria was 2.0 to 6.3 Log₁₀ Cfu g^?1 dry weight and concentrated in RP-amended piles. Humic acid of compost was classified as rotteprudukte. Final pH (7.5 to 8.0) and germination index (>90) proved that the compost was mature. P₃ compost (1 t ha^?1, fresh weight) had potential to supply 25 kg phosphorus.  相似文献   

Induction of fertilizable eggs by conspecific vitellogenin implantation in captive female walking catfish,Clarias batrachus (Linn.)          下载免费PDF全文

Debapriya Bhattacharya  Shrabanti Sarkar  Subir Kumar Juin  Panchanan Nath 《Aquaculture Research》2018,49(9):3167-3175

The synthesis of vitellogenin (Vg) is induced by conspecific Vg (Vg1 and Vg2) and estradiol‐17β (E₂) as demonstrated by the pattern of ³H‐serine incorporation in the liver and plasma proteins. The incorporation studies indicated that the label was first incorporated into the liver after which it appeared in the blood in both E₂‐ and Vg‐treated male catfish. Since Vg was capable of inducing its own synthesis, experiments were conducted in females during preparatory–prespawning period (March–May) to make them gravid by implanting Vg pellets. Two implantations of 4 mg Vg1 pellets into female catfish with an interval of 15 days, followed by laboratory maintenance for 45 days of initial implantation showed a significant increment in ovarian weight with concomitant formation of yolky oocytes through synthesis and incorporation of Vg, whereas Vg2 implantation was not effective in this regard. Histological observation of yolky oocytes in Vg1‐treated group showed the peripheral migration of germinal vesicle (eccentric germinal vesicle), which indicates the onset of maturation. On 45th day, third implantation with 2 mg Vg pellets was performed and after 15 days, fish were hormonally induced with a single injection of hCG (2,000 IU/kg fish). Six groups were considered such as initial control, BSA‐implanted control, Vg1‐implanted, Vg2‐implanted, catfish collected from the field on the last day of the experiment and catfish collected during spawning period in this experiment with 3–7 fish in each group. Each of the experimental fish was sexually mature and the body weight was between 100 and 125 g. The percentage of ovulation and fertilization in the eggs of Vg1‐implanted group was 91% and 78%, respectively, which was almost similar to that of gravid female catfish collected during breeding period (July). The breeding performance in BSA‐ and Vg2‐treated females was very poor. The fertilized eggs were hatched in the laboratory conditions. Thus, in the female catfish, Vg1 not only induces vitellogenesis but also makes the oocytes viable for fertilization.  相似文献