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Extracellular polymeric substances (EPS) are important structural components of biofilms. In the present study, the EPS in biofilms developed using two agriculturally beneficial organisms—Azotobacter chroococcum (Az) and Trichoderma viride (Tv) were quantified and characterised. Time course experiments were undertaken to optimise the EPS yield of biofilm samples resulting from coculture and staggered inoculation. The EPS produced during biofilm formation was found to differ quantitatively and qualitatively in individual cultures (Az alone, Tv alone), and in treatments differing in the sequence of inoculation of bacterium and fungus (Az + Tv coculture, staggered inoculation of Az followed by Tv i.e. Az - Tv, or Tv followed by Az i.e. Tv - Az). Significant enhancement in terms of growth and biofilm formation, as compared to individual inoculation was recorded, with Tv - Az exhibiting higher values of these attributes. The EPS from biofilms showed significantly higher concentrations of protein, acetyl, and uronic acids, while planktonic EPS recorded higher total carbohydrates. Fourier transform infrared spectroscopy analyses illustrated the significant influence on chemical and structural aspects of EPS (planktonic and biofilm). This represents a first report correlating EPS production, cell aggregation and biofilm formation during bacterial-fungal biofilm development, which can have implications in the colonisation of soil and plants. [ABSTRACT FROM AUTHOR]

Abstract: Field evaluation of two fly ashes (40t/ha) on persistence, mobility and bioactivity of metribuzin and metsulfuron-methyl was studied in soybean and wheat crops, respectively. Metribuzin was applied as pre-emergence at 0.5kg/ha, while metsulfuron-methyl was applied post-emergence at 8g/ha. Results suggested that metribuzin in surface (0–15cm) soil of fly ash unamended plots reached below detectable limit in 60 days, while herbicide persisted till 112 days in surface soil of fly ash amended plots. No metribuzin leached down to subsurface (15–30cm) soil in fly ash amended plots, while traces of metribuzin (0.6–1.2μg/kg) were recovered in subsurface soil of fly ash unamended plot. Metsulfuron-methyl in surface soil persisted till 15 days in control and 20 days in fly ash amended plots and no metsulfuron-methyl leached down to subsurface soil. Fly ash amendment had no adverse effect on the bioactivity of herbicides and yield of soybean and wheat. The study suggested that fly ash amendment to soil can be exploited to retain applied herbicides in surface soil. [Copyright &y& Elsevier]

Rhodiola sp. (R. heterodanta and R. imbricata), belonging to the stone crop family Crassulaceae, is an important medicinal plant and food crop in Trans-Himalayan cold desert. It is a well known medicinal plant in the Amchi system of medicine (Tibetan system of medicine) being used in various ailments like anti-stress, radio-protective, anticancer, anti-inflammatory agent, adaptogen etc. Hydro- alcoholic extracts of Rhodiola sp. root and shoot were investigated in the present study to quantify total Phenolic as well as anti-oxidant activity. Total phenolic contents were determined as total flavonoids (TF), and total polyphenols (TPP). Rhodiola heterodanta root extract had highest amount of total phenol and flavonoids are found to be 79.21±.26 mg GAE/g and 269.3±.82mg Qc/g respectively. In vitro antioxidant activity was investigated by DPPH radical scavenging activity, reducing power assay. R. imbricata hydro-alcoholic root extract showed the highest reducing power and DPPH. radical scavenging. A significant correlation existed between concentrations of the extract and percentage inhibition of free radicals and reducing power. These results clearly indicate that Rhodiola sp. are effective against free radical mediated diseases and also helpful to draw special attention for further studies. [ABSTRACT FROM AUTHOR]

The antioxidant activity and phytochemical investigation on Dracocephalum heterophyllum Benth. used in the traditional medicine of Ladakh was carried out. The studies on ethnomedicine keenly represent the search for new economic plants for developing modern medicines. The methanol extract was subjected to antioxidative assay using 2,2’- diphenylpicryl-1-hydrazyl (DPPH) and various biochemical tests of aqueous and chloroform extracts were performed. The results indicated that the plant was rich in tannins, flavonoids, saponins, steroids and alkaloids. The free radical scavenging and antioxidant activities may be attributed to the presence of phenolic and flavonoid compounds present in the extract. The results obtained in the present study indicate that Dracocephalum heterophyllum Benth. is a potential source of natural antioxidants. [ABSTRACT FROM AUTHOR]

Oxygen-compromised environments, such as high altitude, air travel, and sports, and pathological conditions, such as solid tumors, have been suggested to be prothrombotic. Despite the indispensable role of platelets in thrombus formation, the studies linking hypoxia, platelet reactivity, and thrombus formation are limited. In the present study, platelet proteome/reactivity was analyzed to elucidate the acute hypoxia-induced prothrombotic phenotype. Rats exposed to acute simulated hypoxia (282 torr/8% oxygen) demonstrated a decreased bleeding propensity and increased platelet reactivity. Proteomic analysis of hypoxic platelets revealed 27 differentially expressed proteins, including those involved in coagulation. Among these proteins, calpain small subunit 1, a 28-kDa regulatory component for calpain function, was significantly upregulated under hypoxic conditions. Moreover, intraplatelet Ca2+ level and platelet calpain activity were also found to be in accordance with calpain small subunit 1 expression. The inhibition of calpain activity demonstrated reversal of hypoxia-induced platelet hyperreactivity. The prothrombotic role for calpain was further confirmed by an in vivo model of hypoxia-induced thrombosis. Interestingly, patients who developed thrombosis while at extreme altitude had elevated plasma calpain activities and increased soluble P-selectin level. In summary, this study suggests that augmented calpain activity is associated with increased incidence of thrombosis under hypoxic environments. [ABSTRACT FROM AUTHOR]