Perumal Palani

Stabilization of mitochondrial and microsomal function of fucoidan from Sargassum plagiophyllum in diethylnitrosamine induced hepatocarcinogenesis

Crude fucoidan from Sargassum plagiophyllum extracted from blade and purified by Q-Sepharose fast flow anion-exchange chromatography and three fucoidan fractions were obtained. Maximum sulphate containing fucoidan fraction was considered as purified fucoidan and purity was checked with agarose gel electrophoresis. The monosaccharides of purified fucoidan analysed by HPLC revealed the presence of the sugars such as fucose as a major sugar were 70.8 mol%. The percentages of other sugars were galactose (13.5%), xylose (2.5%) and mannose (11.2%). GPC was used to analyse molecular weight of purified fucoidan and it was found to be 35 kDa. The levels of ICDH, SDH, MDH, a-KGDH, Phase-I biotransformation enzymes, and Phase-II biotransformation enzymes were decreased in cancer bearing animals which may be due to oxidative stress and mitochondrial damage and fucoidan restored these enzyme activities. The inhibition of carcinogen metabolic activation indicates the anticancer activity of fucoidan in DEN induced liver cancer.

In Vitro Antioxidant and Anticancer potential of Bark of Costus pictus D.DON

Abstract Objective To evaluate the antioxidant and anticancer potential of different fractions of bark of Costus pictus using various in vitro antioxidant assay systems. Methods In this study, assay like DPPH radical, superoxide anion radical scavenging activity, nitric oxide scavenging activity, hydrogen peroxide scavenging activity, metal chelating activity and reducing power were used. The concentrations of total phenolic and flavonoids were also calculated for the extracts. Result The present study elucidated for the first time the antioxidant property of bark of C. pictus . This study suggested that, among the three fractions, the chloroform fraction possesses high antioxidant activity which might be helpful in preventing or slowing the progress of various oxidative stress related disorders. Moreover, all fractions possess potent anticancer properties against colon cancer cells of HT29 and lung carcinoma cells of A549. Conclusions It can be concluded that the extract of the bark of C. pictus has potential natural antioxidant and this can be used in food industries. There are few reports on the antioxidant capacity of bark of C. pictus and the mechanism of different fractions of bark of C. pictus as antioxidative agents is still not fully understood. Hence further research is underway to analyse and isolate the active compounds responsible for the antioxidant and anticancer activity of different fractions of the bark of C. pictus .

Studies on screening, isolation and purification of a fibrinolytic protease from an isolate (VK12) of Ganoderma lucidum and evaluation of its antithrombotic activity.

Antithrombotic activity of a protease purified from a medicinal mushroom, Ganoderma lucidum, has been evaluated platelet aggregation in vitro and pulmonary thrombosis in vivo. The purified protease exhibited concentration dependent inhibitory effects on platelet aggregation induced by ADP (adenosine diphosphate), with an IC(50) value of 2.4 mg/mL. The purified protease protected mice against thrombotic death or paralysis induced by collagen and epinephrine in a dose dependent manner when administered orally. It produced a significant inhibition of thrombotic death or paralysis at 60 µg/kg body weight, while aspirin produced a significant inhibition of thrombosis at 10-20 mg/kg body weight. The purified protease also has showed fibrinolytic activity and alters coagulation parameters such as activated partial thromboplastin time (APTT), and thrombin time (TT) in rat platelet. These results suggested that the antithrombotic activity of Ganoderma lucidum protease might be due to antiplatelet activity rather than anticoagulation activity.

Biosynthesis, purification and characterization of polyhydroxybutyrate from Botryococcus braunii kütz.

Polyhydroxybutyrate (PHB) is completely biodegradable which is metabolised by microorganisms in the soil as their sole food source in few years. The level of PHB up to 10.6% of algal dry weight is of great potential of the eco-friendly nature. Botryococcus braunii is mainly used for the production of biodiesel and is also capable of producing biopolymer polyhydroxy butyrate (PHB). In this study, Botryococcus braunii is used which generally produce PHB to around 20% of the dry weight. Three different microalgae were isolated from the fresh water of Kolavoi lake of Tamil Nadu. They were identified by their morphological features under the light microscope. The primary screening of PHB intracellular granules was made by using Nile red dye under a fluorescent microscope. Among them, Botryococcus braunii showed high accumulation of PHB granules. For authentic confirmation, the chloroform extracted PHB was analysed by FTIR, XRD and DSC-TGA analyses to characterize PHB with commercial biodegradable thermoplastic. This is the first report in B. braunii for its PHB production.

Isolation, purification and characterization of antimicrobial protein from seedlings of Bauhinia purpurea L.

A novel antimicrobial protein was purified from the seedlings of Bauhinia purpurea by sequential procedures entailing ammonium sulfate precipitation, cation exchange chromatography, preparative native-PAGE and a yield of 2.7% was obtained from the crude extract. The purified antimicrobial protein appeared as a single protein band on SDS-PAGE with the molecular mass of 20.9 kDa. Purified antimicrobial protein exhibited a potent antimicrobial activity against both Gram-positive and Gram-negative bacteria. Analysis of the trypsin digested peptides of purified protein using the MALDI-TOF MS/MS resulted in the identification of 174 amino acids. The purified protein had an optimum of pH of 5.5 and was stable at 35 °C for exhibiting its maximal antibacterial activity. The addition of metal ions such as Mn(2+) and Ca(2+) to the purified protein enhanced the antimicrobial activity of purified protein. The MIC of purified protein against Bacillus cereus and Escherichia coli were 13 μg/ml and 15 μg/ml, respectively. The purified protein digested the peptidoglycan layer of bacteria which was visualized by TEM analysis.

Optimization of polyhydroxybutyrate production utilizing waste water as nutrient source by Botryococcus braunii Kütz using response surface methodology

Investigations have been made to optimize various factors including pH, temperature, and substrate for enhanced polyhydroxybutyrate (PHB) production in Botryococcus braunii which serves as a pioneer for production of bioplastic (PHB). Polyhydroxybutyrate is a natural, decomposable polymers accumulated by the microorganism under different nutritional condition. Strain selection was done by staining method using Sudan black and Nile red dye. Using response surface methodology (RSM), three level- three variables Box Behnken design (BBD), the best potential combination of pH (4-11), temperature (30-50°C) and sewage waste water as substrate fed at different concentrations at 20%-100% for maximum PHB production was investigated. Maximum yield (247±0.42mg/L) of PHB dry weight was achieved from the 60% concentration of sewage waste water as a growth medium at pH 7.5 at 40°C. It was well in close agreement with the value predicted by RSM model yield (246± 0.32mg/L). Thus the study shows the production of PHB by B. braunii along with the basic characterization of PHB by using FTIR and TEM analysis. These preliminary studies indicated that PHB can also be produced by B. braunii utilizing waste water. There is no report on the optimization of PHB production in this microalgae have been documented.

Mass cultivation of UV-B adapted Arthrospira platensis RRGK under open raceway pond for the production of Poly-β-hydroxy butyrate

Six different strains of cyanobacteria were isolated from the freshwater lake, Arakkonam, India. Staining of cells with Nile Red showed the presence of large quantities of PHB granules in the cell cytoplasm of Arthrospira. Molecular identification of the strain was carried out using 16S rRNA analysis and their systematic position was ascertained as Arthrospira platensis RRGK. Studies were carried out on random mutagenesis approach using UV-B radiation for enhancing the production of PHB. Further, Response Surface Methodology was used for optimization of pH, temperature, and sodium bicarbonate for higher biomass and PHB production. Under open raceway pond A. platensis RRGK produced biomass concentration of 2.2±0.13gL-1 and 131±0.36gL-1 of PHB content. It was chemically characterized through FTIR, DSC, TGA and XRD analyses. Hence, PHB can be produced from cyanobacteria by sequestering harmful CO2. It can also be used as a substitute for synthetic polymers in tissue engineering.

Antioxidant properties of sequential extracts from brown seaweed, Sargassum plagiophyllum, C. Agardh

Objective To study the antioxidant properties of sequential extracts of Sargassum plagiophyllum.

Daldinia sacchari (Hypoxylaceae) from India produces the new cytochalasins Saccalasins A and B and belongs to the D. eschscholtzii species complex

Stromata of a Daldinia species were collected from half-burnt sugarcane stalks in South India. Based on a combination of morphological and chemotaxonomic evidence, the species was identified as the first recent record of Daldinia sacchari. While it was impossible to obtain cultures from the ascospores, the stromata were subjected to DNA extraction and DNA sequencing and secondary metabolites were analyzed by high-performance liquid chromatography coupled with diode array and mass spectrometric detection (HPLC-DAD/MS). The fruiting body extract was subjected to preparative HPLC for the isolation of secondary metabolites. Two new cytochalasins, for which we propose the trivial names saccalasins A and B, were elucidated besides two known cytochalasins and binaphthalene tetrol (BNT) by NMR spectroscopy and mass spectrometry. Whereas sequencing of housekeeping genes from the stromatal DNA unfortunately failed, an ITS DNA sequence was obtained from this species for the first time and compared to those of related Hypoxylaceae in a phylogenetic tree. The results indicate a close relationship of D. sacchari to the D. eschscholtzii complex, from which cytochalasins are also known as predominant stromatal metabolites. Phylogenetic analyses based on the ITS-rDNA barcode (which can only discriminate the Hypoxylaceae and other Sordariomycetes into species groups, rather than serve as a means of genus or species discrimination) confirmed that D. sacchari belongs to the D. eschscholtzii species complex. However, as with the majority of tropical Hypoxylaceae species, the availability of cultures that can be used to generate DNA sequence data that are more conclusive than ITS will be imperative to further narrow down the phylogenetic affinities of these fungi.

Bioactive potential and composition analysis of sulfated polysaccharide from Acanthophora spicifera (Vahl) Borgeson

Marine seaweeds contain a valuable source of functional bioactive polysaccharide and it plays main role for effective anticancer activity. The structural feature of SPs was studied through FT-IR and 1H NMR spectra analysis. The isolated SPs from A. spicifera contain 63.3% of total sugar, 21.9% of total sulfate and 12.6% of total uranic acid was found. The active F2 fraction molecular weight of SP was found to be 420 kDa. The sugar was composed of galactose (73.5%), xylose (9.2%), mannose (1.9%) and arabinose (10.9%). Further the SP showed DPPH free radical scavenging activity of 55.55% at 150 μg/mL and reducing power activity of 91.3% at 125 μg/mL. In the present study, the purified sulfated polysaccharide (fraction F2) were extracted, purified and characterized for red seaweed and evaluated for their potential anticancer activity of in A549 cell lines under in vitro condition. These polysaccharide fractions exhibited potential apoptotic effects on A549 cell lines.