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The properties of humic (HA) and fulvic acids (FA) isolated from a 27-year-old long-term experiment with rice-wheat-cowpea on a Mollisol in northern India were evaluated for elemental composition and functional groups. As compared to fallow, C, H and N decreased, while O increased in the control, but the use of NPK+FYM over the years enhanced the C and N of humic substances. The carboxylic (-COOH) and phenolic-OH groups declined in the control, but improved with NPK+FYM in comparison to fallow. Carboxylic groups (-COOH) contributed about 2–3 times more in HA and 4–5 times more in FA than the respective phenolic-OH groups to the molecular weights of these fractions of soil organic matter. The results suggested the role of integrated nutrient management in maintaining active soil humus over the years.

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Bipolaris sorokiniana (Sacc.) Shoemaker (Teleomorph: Cochliobolus sativus (Ito and Kuribayashi) Drechs. Ex. Dastur) is a serious necrotrophic pathogen of wheat and barley in several countries. In this paper we report on mechanism of resistance and histopathological changes that occur on pathogen attack in resistant and susceptible genotypes. Callose deposition was observed in the epidermal cell wall of resistant genotype, Pusa T3336 at 2DAI. Lignin deposition around mesophyll tissues was also strongly observed by Phloroglucinol-HCl test in Pusa T3336. Four days after inoculation (4DAI), the pathogen colonized the leaf tissues showing inter and intracellular hyphae in susceptible genotype, Agralocal. In resistant genotype, no colonization was observed. The host tissue in susceptible genotype showed degeneration away from the site of colonization and also showed loss of structural integrity thereby indicating the role of toxin in pathogenesis. Separation of plasmalemma from the cell wall was observed due to loss of electrolytes and degradation of chloroplast at 5 DAI in the susceptible genotypes was prominently seen through light microscopy.

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Fire is a constitutive ecological force in savanna ecosystems, but few studies have monitored its short-term effects on plant community dynamics. This study investigated changes in plant diversity in the South American savanna (Cerrado) after severe disturbance by fire. We monitored 30 permanent plots (10 m × 5 m) distributed in two Cerrado physiognomies (típico: more forested; ralo: grass-dominated), being 10 plots in the area disturbed by fire, and five in a preserved control area (undisturbed). From August 2010 to June 2011, we evaluated changes in species richness, abundance and composition of savanna vegetation. Monitoring started one week after the fire; disturbed plots were surveyed monthly, while control plots were surveyed every two months. We observed rapid reassembling in both physiognomies: plots affected by fire showed rapid increase in species richness and plant density during the first four months after the disturbance. Concerning species composition, disturbed plots in the cerrado típico tended to converge to control plots after one year, but each local assemblage followed particular temporal trajectories. A different pattern characterized cerrado ralo plots, which showed heterogeneous trajectories and lack of convergence between disturbed and control plots; the structure of these assemblages will likely change in next years. In conclusion, our results showed that fire significantly affected plant diversity in the two savanna physiognomies (cerrado típico and ralo), but also indicated that community reassembling is fast, with different dynamics between Cerrado physiognomies.

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Acta Alimentaria
Authors:
D. Das
,
S. Tamuly
,
M. Das Purkayastha
,
B. Dutta
,
C. Barman
,
D.J. Kalita
,
R. Boro
, and
S. Agarwal

Abstract

Green tea or its concentrated extract is coveted for its health promoting catechin-like polyphenols, especially epigallocatechin-3-gallate (EGCG). However, its amicable efficacy is now being doubted considering the recent occurrence of several cases of hepato- and nephrotoxicity, after the ingestion of EGCG-fortified (≥85–90%) nutritional supplements. Therefore, the current study was carried out to ascertain the effect of green tea leaves extract (GTE), having low EGCG content (73.8%), on liver and kidney functions of male Wistar rats using various in vivo experiments and in vitro radical scavenging activity. In terms of acute toxicity, GTE was observed to be safe when delivered at a dosage of 2000 mg kg−1 body weight (BW). Oral delivery of GTE for 28 days at a concentration of 200 mg kg−1 BW/day did not trigger sub-acute toxicity to the liver and kidneys, as per serum biochemical analyses and histopathological examination. In contrast, GTE counteracted the effects of carbon tetrachloride (a potent hepato-degenerative compound) on the liver. Furthermore, increase in high-density lipoprotein―cholesterol with concomitant lowering of serum triglycerides and low-density lipoprotein―cholesterol were noticed in GTE-treated rats. These findings suggest that low EGCG containing GTE, with appreciable antioxidant activity (IC50 = 53.18–71.28 μg mL−1), can serve as a hepatoprotective, hypolipidemic, and hypocholesterolemic ingredient.

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Pomelo fruit juice is concentrated using two different techniques, i.e. block freeze concentration (BFC) and thermal concentration (TC), and both concentrates were spray dried separately to observe the effects of two different concentration techniques on the physicochemical properties of the spray dried powder. BFC juice had comparatively better values of retention of acidity, colour, vitamin C, DPPH● scavenging activity, total phenolic content (TPC), and total sugar content than TC juice. The powder obtained from the combination of BFC and spray drying had better retention of vitamin C (121.17 mg/100 g), colour, and exhibited higher DPPH● scavenging activity than TC spray dried powder. The physical parameters including solubility index, bulk density, and hygroscopicity were significantly higher in BFC spray dried powder. BFC was observed as an efficient concentration technique in comparison to TC as a pretreatment to produce spray dried powder with a better retention of bioactive components and powder flow properties.

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Cereal Research Communications
Authors:
R. Ponnuswamy
,
A. Rathore
,
A. Vemula
,
R.R. Das
,
A.K. Singh
,
D. Balakrishnan
,
H.S. Arremsetty
,
R.B. Vemuri
, and
T. Ram

The All India Coordinated Rice Improvement Project of ICAR-Indian Institute of Rice Research, Hyderabad organizes multi-location testing of elite lines and hybrids to test and identify new rice cultivars for the release of commercial cultivation in India. Data obtained from Initial Hybrid Rice Trials of three years were utilized to understand the genotype × environment interaction (GEI) patterns among the test locations of five different agro-ecological regions of India using GGE and AMMI biplot analysis. The combined analysis of variance and AMMI ANOVA for a yield of rice hybrids were highly significant for GEI. The GGE biplots first two PC explained 54.71%, 51.54% and 59.95% of total G + GEI variation during 2010, 2011 and 2012, respectively, whereas AMMI biplot PC1 and PC2 explained 46.62% in 2010, 36.07% in 2011 and 38.33% in 2012 of the total GEI variation. Crossover interactions, i.e. genotype rank changes across locations were observed. GGE biplot identified hybrids, viz. PAN1919, TNRH193, DRH005, VRH639, 26P29, Signet5051, KPH385, VRH667, NIPH101, SPH497, RH664 Plus and TNRH222 as stable rice hybrids. The discriminative locations identified in different test years were Coimbatore, Maruteru, VNR, Jammu, Raipur, Ludhiana, Karjat and Dabhoi. The AMMI1 biplot identified the adaptable rice hybrids viz., CNRH102, DRH005, NK6303, NK6320, DRRH78, NIPH101, Signet5050, BPH115, Bio452, NPSH2003, and DRRH83. The present study demonstrated that AMMI and GGE biplots analyses were successful in assessing genotype by environment interaction in hybrid rice trials and aided in the identification of stable and adaptable rice hybrids with higher mean and stable yields.

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European Journal of Microbiology and Immunology
Authors:
Gangadhararao Appana
,
Dipankar Das
,
Maroudam Veerasami
,
Ramachandran Lakshmikanthan Senthilkumar
,
Munishkumar Durishetty
,
B. Ramalakshmi
,
Vijay Bahekar
,
Falguni Mukherjee
,
Dev Chandran
,
P. Uday Kumar
,
B. Sesikeran
, and
Dr. Villuppanoor Alwar Srinivasan Ph.D.

Abstract

A male cattle calf was detected as subclinically and naturally infected with Mycobacterium avium subspecies paratuberculosis (MAP) by a series of antemortem and postmortem tests. The MAP infection was identified by strong antibody and cell-mediated immune (CMI) response by a commercial ELISA kit and an intradermal Johnin test, respectively, in the initial antemortem examination. The antemortem status of the calf was further confirmed by MAP-specific interferon gamma (IFN-γ) response. For detection of IFN-γ response, MAP-specific IFN-γ release assays (IGRAs): (a) immuno capture ELISA (IC-ELISA) and (b) ELISPOT was employed. In addition, the presence of intracellular cytokine IFN-γ was detected by flow cytometry. For all cytokine assays, MAP-specific recombinant antigens HSP65 and 35 kDa were employed to overcome the poor sensitivity and specificity resulting from the use of Johnin, the crude protein purified derivative of MAP. Postmortem examination of the MAP-infected/suspected cattle calf did not reveal any pathognomonic gross lesions in the gastro-intestinal tract. Histopathological examination of multiple organs showed the presence of epithelioid cells/macrophages and edematous lesions in the mesenteric lymph nodes suggestive of MAP; however, no granulomas were observed in the intestinal tract. The necropsy samples of rectum and mesenteric lymph nodes were positive for isolation of MAP by culture in the BACTEC™ MGIT™ 960 system, and acid fast bacilli were demonstrated by fluorescence microscopy confirming the infection. Due to differential and complex expression patterns of MAP antigens reported in literature, a combination of assays such as those based on IGRAs and antibody detection is essential. Therefore, the current experimental evidence confirms the efficacy of the approach adopted. However, further studies will be needed to understand the optimal combination MAP-specific antigens for use in IGRAs or antibody assays that can be used for detecting MAP infection in every stage of the disease.

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