Assessment of optimal growth conditions for specific carotenoids production by Chlorella vulgaris

Exploration of regional microalgae for carotenoids production under optimized cultural conditions is a sustainable economic and technical perspective. This study details comprehensive research on the influence of growth conditions on microalgal carotenoids. Carotenoid triggering factors were optimized to identify suitable growth conditions to produce specific carotenoids by Chlorella vulgaris.  Media optimization and cultivation conditions were the factors considered and the results revealed the optimum growth conditions for carotenoid production by C. vulgaris was pH 8, 35°C temperature, 0.04 M salinity and 160 µE\m²\sec light intensity. Among the nutrient sources, potassium nitrate and potassium phosphate were suitable for nitrogen and phosphorous supplements. The results indicated optimizing the culture conditions and nutrient sources help to attain desirable carotenoid production by C. vulgaris. Specific carotenoids were extracted from the algal extract and were identified by high-performance liquid chromatography in which lutein (8.8%) was present as major carotenoid followed by astaxanthin (4.6%) and ?-carotene (3.9%). This study revealed that that carotenoid production by C. vulgaris could be enhanced by manipulating culture conditions thereby attain desirable carotenoid production.

Screening for resistance to downy mildew disease [Pseudoperonospora cubensis (Berk. and Curt.) Rostov.] in Cucumber (Cucumis sativus L.)

Downy mildew, a foliar disease caused by the oomycete Pseudoperonospora cubensis (Berk. and Curt.) Rostov, is one of the most destructive disease of cucumber (Cucumis sativus L.). Moderately resistant cultivars are available, but yield losses are high without the use of fungicides, therefore, higher levels of resistance are required to reduce the use of fungicides. Therefore, in the present study, 12 advance breeding lines along with susceptible check of cucumber were screened against downy mildew disease under natural field condition and artificial inoculation through seedling assay technique. The results confirmed that three lines namely IIHR-177-1-1-S7, IIHR-82-1-S6 and IIHR-81-1-S6 were found to be resistant with <10 per cent disease index (PDI) and significantly outperformed against check var. Swarna Agethi for yield and quality traits. These high yielding resistant lines can be utilized as one of the parents for the development of downy mildew resistant hybrids/ varieties

In vitro anti-inflammatory, anti-diabetic and antioxidant potential of Cissus quadrangularis along with its orexigenic activity in Drosophila melanogaster

Plants with diverse pharmacological activities are actively being explored for human health. Cissus quadrangularis (L) has been reported to possess numerous phytochemicals and is used to relieve various disorders. This article aims at providing evidence of the diverse pharmacological activities in terms of orexigenic, anti-inflammatory, anti-diabetic and antioxidant activities of C. quadrangularis for further application in clinical development. The results revealed that inhibition of hemolysis was within the range of 8-9-25.6% at concentrations of 12.5-200 µg/ml. Methanol extract of C. quadrangularis stems exhibited porcine pancreatic ?-amylase (PPA) inhibition (p?0.05) at concentrations of 0.25 and 0.30 mg/ml. The glucose adsorption capacity of the C. quadrangularis was observed to be inversely proportional to the molar concentration of glucose. The higher food intake by Drosophila in food medium with plant extract is presumably related to orexigenic property of C. quadrangularis. Protease activity of C. quadrangularis stem extract revealed total activity 975 U/ml and specific activity as 3768 U/mg. The absorbance of C. quadrangularis in reducing power assay were between 0.91and 1.85. Highest total antioxidant activity of 67.2 µg TE/g was observed and the hydroxyl radicals scavenging activity was observed in a dose dependent manner. The results provide supporting data that C. quadrangularis may contain active compounds useful in treating anti-inflammatory, anti-diabetic disorders

To hydrolyze or not to hydrolyze: The dilemma of platelet-activating factor acetylhydrolase

Mounting ambiguity persists around the functional role of the plasma form of platelet-activating factor acetylhydrolase (PAF-AH). Because PAF-AH hydrolyzes PAF and related oxidized phospholipids, it is widely accepted as an anti-inflammatory enzyme. On the other hand, its actions can also generate lysophosphatidylcholine (lysoPC), a component of bioactive atherogenic oxidized LDL, thus allowing the enzyme to have proinflammatory capabilities. Presence of a canonical lysoPC receptor has been seriously questioned for a multitude of reasons. Animal models of inflammation show that elevating PAF-AH levels is beneficial and not deleterious and overexpression of PAF receptor (PAF-R) also augments inflammatory responses. Further, many Asian populations have a catalytically inert PAF-AH that appears to be a severity factor in a range of inflammatory disorders. Correlation found with elevated levels of PAF-AH and CVDs has led to the design of a specific PAF-AH inhibitor, darapladib. However, in a recently concluded phase III STABILITY clinical trial, use of darapladib did not yield promising results. Presence of structurally related multiple ligands for PAF-R with varied potency, existence of multi-molecular forms of PAF-AH, broad substrate specificity of the enzyme and continuous PAF production by the so called bi-cycle of PAF makes PAF more enigmatic. This review seeks to address the above concerns

Lipopolysaccharide cross-tolerance delays platelet-activating fctor-induced sudden death in wwiss albino mice: Involvement of cyclooxygenase in Ccoss-tolerance

Lipopolysaccharide (LPS) signaling through Toll-like receptor-4 (TLR-4) has been implicated in the pathogenesis of many infectious diseases. Some believe that TLR-mediated pathogenicity is due, in part, to the lipid pro-inflammatory mediator platelet-activating factor (PAF), but this has been questioned. To test the direct contribution of PAF in endotoxemia in murine models, we injected PAF intraperitoneally into Swiss albino mice in the presence and absence of LPS. PAF alone (5 μg/mouse) caused death within 15–20 min, but this could be prevented by pretreating mice with PAF-receptor (PAF-R) antagonists or PAF-acetylhydrolase (PAF-AH). A low dose of LPS (5 mg/kg body wt) did not impair PAF-induced death, whereas higher doses (10 or 20 mg/kg body wt) delayed death, probably via LPS cross-tolerance. Cross-tolerance occurred only when PAF was injected simultaneously with LPS or within 30 min of LPS injection. Tolerance does not appear to be due to an abundant soluble mediator. Histologic examination of lungs and liver and measurement of circulating TNF-α and IL-10 levels suggested that the inflammatory response is not diminished during cross-tolerance. Interestingly, aspirin, a non-specific cyclooxygenase (COX) inhibitor, partially blocked PAF-induced sudden death, whereas NS-398, a specific COX-2 inhibitor, completely protected mice from the lethal effects of PAF. Both COX inhibitors (at 20 mg/kg body wt) independently amplified the cross-tolerance exerted by higher dose of LPS, suggesting that COX-derived eicosanoids may be involved in these events. Thus, PAF does not seem to have a protective role in endotoxemia, but its effects are delayed by LPS in a COX-sensitive way. These findings are likely to shed light on basic aspects of the endotoxin cross-tolerance occurring in many disease conditions and may offer new opportunities for clinical intervention

Evaluation of potential and non-potential <i>B</i>. <i>bassiana</i> against <i>T</i>. <i>truncatus</i>.

Evaluation of potential and non-potential B. bassiana against T. truncatus.</p

Thin Layer Chromatography of six <i>B</i>. <i>bassiana</i> strains.

Mobile phase was Toulene, ethyl acetate, and formic acid (5:4:1). (TIF)</p

GC-MS chromatogram of secondary metabolites from Bb5 strain of <i>B</i>. <i>bassiana</i>.

(TIF)</p

Morphological observations of <i>B</i>. <i>bassiana</i>.

Colony appearance on PDA a) front view; b) reverse view; c) conidial cluster under SEM; d) conidia.</p