NOPR Collection: Pages 225-292

Dynamism of PGPR in bioremediation and plant growth promotion in heavy metal contaminated soil

2016-07-20T06:50:18Z

Title: Dynamism of PGPR in bioremediation and plant growth promotion in heavy metal contaminated soil Authors: Patel, PR; Shaikh, SS; Sayyed, RZ Abstract: Heavy metal contamination, particularly of cultivable lands, is a matter of concern. Bioremediation helps in reversing such contamination to certain extent. Here, we report isolation, polyphasic identification and the role of siderophore producing rhizobacteria Alcaligenes feacalis RZS2 and Pseudomonas aeruginosa RZS3 in bioremediation of heavy metal contaminated soil and plant growth promotion activity in such contaminated soil. Siderophore produced by A. feacalis RZS2 and P. aeruginosa RZS3 strains chelated various heavy metal ions like MnCl₂.4H₂O, NiCl₂.6H₂O, ZnCl₂, CuCl₂ and CoCl₂ other than FeCl₃.6H₂O at batch scale. Their bioremediation potential was superior over the chemical ion chelators like EDTA and citric acid. These isolates also promoted growth of wheat and peanut seeds sown in heavy metal contaminated soil. Effective root colonizing ability of these isolates was observed in wheat and peanut plants. Page(s): 286-290

Scavenging and antioxidant properties of different grape cultivars against ionizing radiation-induced liver damage ex vivo

2016-07-20T06:48:12Z

Title: Scavenging and antioxidant properties of different grape cultivars against ionizing radiation-induced liver damage ex vivo Authors: Singha, Indrani; Das, Subir Kumar Abstract: Ionizing radiation (IR) has become an integral part of the modern medicine— both for diagnosis as well as therapy. However, normal tissues or even distant cells also suffer IR-induced free radical insult. It may be more damaging in longer term than direct radiation exposure. Antioxidants provide protection against IR-induced damage. Grapes are the richest source of antioxidants. Here, we assessed the scavenging properties of four grape (Vitis vinifera) cultivars, namely Flame seedless (Black), Kishmish chorni (Black with reddish brown), Red globe (Red) and Thompson seedless mutant (Green), and also evaluated their protective action against -radiation-induced oxidative stress in liver tissue ex vivo. The scavenging abilities of grape seeds [2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC₅₀=0.008±0.001 mg/mL), hydrogen peroxide (IC₅₀=0.49 to 0.8 mg/mL), hydroxyl radicals (IC₅₀=0.08±0.008 mg/mL), and nitric oxide (IC₅₀=0.8±0.08 mg/mL)] were higher than that of skin or pulp. Gamma () radiation exposure to sliced liver tissues ex vivo from goat, @ 6 Gy significantly (P <0.001) decreased reduced glutathione (GSH) content by 21.2% and also activities of catalase, glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione s-transferase (GST) by 49.5, 66.0, 70.3, 73.6%, respectively. However, it increased thiobarbituric acid reactive substances (TBARS) by 2.04-fold and nitric oxide level by 48.6% compared to untreated group. Further increase in doses (10 or 16 Gy) of -radiation correspondingly decreased GSH content and enzyme activities, and increased TBARS and nitric oxide levels. Grape extract treatment prior to ionizing radiation exposure ameliorated theses effects at varying extent. The seed extracts exhibited strong antioxidant potential compared to skin or pulp extracts of different grape cultivars against oxidative damage by ionizing radiation (6 Gy, 10 Gy and 16 Gy) in sliced liver tissues ex vivo. Grape extracts at higher concentration (10 mg extract/g liver tissue) showed stronger antioxidant potential against lower dose (6 Gy) of ionizing radiation. Our results suggest that grape extracts could serve as a potential source of natural antioxidant against lower doses of IR-induced oxidative stress in liver extracts ex vivo. Page(s): 280-285

Biomass production of multipopulation microalgae in open air pond for biofuel potential

2016-07-20T06:50:16Z

Title: Biomass production of multipopulation microalgae in open air pond for biofuel potential Authors: Selvakumar, P; Umadevi, K Abstract: Biodiesel gains attention as it is made from renewable resources and has considerable environmental benefits. The present investigation has focused on large scale cultivation of multipopulation microalgae in open air pond using natural sea water without any additional nutritive supplements for low cost biomass production as a possible source of biofuel in large scale. Open air algal pond attained average chlorophyll concentration of 11.01 µg/L with the maximum of 43.65 µg/L as well as a higher lipid concentration of 18 % (w/w) with lipid content 9.3 mg/L on the 10^th day of the culture; and maximum biomass of 0.36 g/L on the 7^thday of the culture. Composition analysis of fatty acid methyl ester (FAME) was performed by gas chromatography and mass spectrometry (GCMS). Multipopulation of algal biomass had 18% of total lipid content with 55% of total saturated fatty acids (SFA), 35.3% of monounsaturated fatty acids (MUFA) and 9.7% of polyunsaturated fatty acids (PUFA), revealing a potential source of biofuel production at low cost. Page(s): 271-279

Growth response modulation by putrescine in Indian mustard Brassica juncea L. under multiple stress

2016-07-20T06:50:15Z

Title: Growth response modulation by putrescine in Indian mustard Brassica juncea L. under multiple stress Authors: Lakra, Nita; Tomar, Pushpa C; Mishra, SN Abstract: Plants, in general, are put to various kinds of stress, biotic and abiotic, both natural and manmade. Infestation by insect pests and diseases, and extreme conditions such as salinity, temperature, etc., as well as heavy metal contamination affect their growth performance. Here, we studied the impact of salinity and heavy metal pollution on the growth performance of Indian Mustard Brassica juncea L. and its amelioration by the diamine, putrescine, a known media supplement. We evaluated the putrescine (Put) modulation potential on multiple stress effect in 7-day old Indian mustard. The germination, seedlings length and photosynthetic pigments decline under salinity and metal (Cd/Pb) stress condition, alone or in combination, were checked by putrescine. The stress induced increase in root-shoot ratio, RNA and total amino acids content, as well as Na⁺/K⁺ ratio in leaf tissues were also comparatively less. The increased endogenous Cd/Pb accumulation in plants exposed to either metal further elevated under salinity was also found decelerated. However, the multiple stressed seedlings showed increase in glutathione content, which was further elevated with putrescine application. The increase in protein contents in leaf under single or combined stresses in the presence of putrescine could be a qualitative change. The differential changes in parameters examined here resulted in improved growth (>10%) suggests stress mitigation by the putrescine up to an extent. Page(s): 262-270