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Thirteen genotypes of sugarcane were exposed to different drought stress intensities followed by a period of stress relief. Different biomarkers were used to analyze the stress tolerance in leaves which include DPPH activity, proline, glycine betaine, lipid peroxidation and phenolic contents against different doses of Polyethylene glycol. Relatively the concentrations of all biochemical markers were increased when PEG concentration was increased. On the basis of lipid peroxidation, glycine betaine and proline contents, HSF-242, Lho-83, HSF-240, CP-77-400, CPF-198, NSG-45, NSG-60 and NSG-555 were found to be drought tolerant genotypes. In conclusion the drought stress-induced changes are reversible, at the cellular level in sugarcane.

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The activity of antioxidative enzymes system is affected by salt stress, chlorophyll content (CHL), leaf relative water content (RWC), Na + and K + contents, their ratio and some oxidative stress indices were studied in leaves of ten bread wheat cultivarsSehar-06, Lu-26, NARC-09, BARC-09 and Pirsbak-09' (salt-tolerant) and Kaghan-94, Rohtas-90, Soughat-90, Shaheen-94 and Zardana-89' (salt-sensitive), grown under salinity treatments carried out in five levels (1 < dS•m −1 as control, 2, 4, 8, 16 dS•m −1) via sodium chloride. Under high salt potency significant increase for activities of antioxidant enzymes such as ascorbate peroxidase (APX) and guiacol peroxidase (GPX), occurred in salt tolerant varieties. Meanwhile, under salinity condition the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and (GPX) in sensitive cultivar were lower than control. Regarding (APX) activity there was no significant difference between salinity and control situation. Under salt stress membrane stability index (MSI) of both cultivars were negatively influenced. Hydrogen peroxide (H 2 O 2) content of salinity sensitive cultivars was higher than control. Salt tolerant varieties had more amounts of K + content, K + and Na + ratio, relative water content, yield and chlorophyll under salt conditions, and sensitive ones recorded higher Na + content at tillering stage. The mechanism of salt stress might be achieved due to low lipid peroxidation, assumingly lower changes in membrane stability index and evasion of Na + combination and amplified activity of antioxidant enzymes.

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Background: The present study compares the protective properties of aqueous extracts of six medicinal plants, Phyllanthus emblica, Terminalia chebula (black and yellow), Terminalia arjuna, Balsamodendron Mukul and Alium sativum against lipid per-oxidation in mice brain. Methods:The antioxidant activities were analyzed by lipid per-oxidation assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay, total antioxidant activity and metal chelation. Results: The extracts (fruits and bark) showed inhibition against thiobarbituric acid reactive species (TBARS) induced by pro-oxidant (10 µM FeSO4) in mice brain. Moreover, the free radical scavenging activities of the extracts was evaluated by the scavenging of DPPH radical (IC 50 , 23.23±1.2 µg/ml (Phyllanthus emblica), 20.24±0.9 µg/ml (Terminalia chebula yellow) and 17.33±1.1 µg/ml (Terminalia chebula black), 19.44±0.45 µg/ml (Terminalia arjuna), 56.59±2.1 µg/ml (Balsamodendron Mukul) and ˂ 200 µg/ml (Alium sativum). Conclusion: The higher antioxidant and inhibitory effect of Terminalia chebula black in this study could be attributed to its significantly higher phenolic content, Fe(II) chelating ability, reducing ability and free radical scavenging activity. Therefore oxidative stress in brain could be potentially prevented by the intake of these plants.

The binary mosquitocidal genes of 51-kDa and 42-kDa proteins isolated from Bacillus sphaericus 1593 have been expressed at moderate levels in Escherichia coli employing the pQE expression system. The expressed proteins are readily visible in Coomassie blue-stained protein gels. The recombinant E. coli cells expressing toxic proteins were toxic towards Culex larvae. During the assembly of crystals in B. sphaericus, the 42-kDa toxin is first cleaved at the N-terminal end by a specific B. sphaericus protease. To express the toxins in E. coli the B. sphaericus specific protease-recognition site was deleted at the N-terminal end of the 42-kDa toxin, thereby mimicking the structure of the toxin as present in the crystal. This modification resulted in a twofold increase in the toxicity of the E. coli cells expressing the modified 42-kDa toxin as a constituent of the binary toxin. Our results demonstrate the utility of this modification for heterologous expression of the binary toxin genes from B. sphaericus.