Thermostablility of phycobiliproteins and antioxidant activity from four thermotolerant cyanobacteria

Four cyanobacterial strains including Cyanosarcina sp. SK40, Phormidium sp. PD40‐1, Scytonema sp. TP40 and Leptolyngbya sp. KC45 were selected and investigated for the phycobiliprotein (PBP) content and thermostable antioxidant activity of their cell‐free extracts. The highest content of 181.63 mg/g dry weight phycobiliprotein was found in Leptolyngbya sp. KC45 with phycoerythrin (PE) as the main phycobiliprotein. Among the PBPs of four thermotolerant cyanobacteria, PE from Leptolyngbya sp. KC45 exhibited the highest thermal stability as 80% of the original level remained after being heated at 60°C for 30 min. Antioxidant activities were detected in the cell‐free extracts of all cyanobacteria and that of Leptolyngbya sp. KC45 was also found in the highest value of 7.44 ± 0.14 and 3.89 ± 0.08 mg gallic acid equivalent (GAE) g^?1 dry weights determined by 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH) and reducing power assay, respectively. This also corresponded to the phenolic compound content. Based on DPPH and reducing power assay, antioxidant activities of all cyanobacterial extracts showed the high thermostability as approximately 80% remained after being heated at 80°C for 30 min. However, it clearly indicated that the thermostability of antioxidant activity from the hot spring cyanobacterial cell‐free extract was not contributed only by the PE, but also came from phenolic compounds and other oxidative substances.     

Diversity of desmids in three Thai peat swamps

Three peat swamps situated in the southern part of Thailand were investigated for their desmid flora in relation to a number of physical and chemical habitat parameters. Altogether, 99 species were encountered belonging to 22 genera. 30 species are new records for the Thai desmid flora. Laempagarung peat swamp showed the highest diversity (45 species), followed by Maikhao peat swamp (32 species) and Jud peat swamp (25 species). Despite its relatively low species richness, Jud swamp appeared to house a number of rare taxa, e.g., Micrasterias subdenticulata var. ornata, M. suboblonga var. tecta and M. tetraptera var. siamensis which can be considered Indo-Malaysian endemics. Differences in composition of the desmid flora between the three peat swamps are discussed in relation to environmental conditions. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.     

Hydrogen production and anaerobic decolorization of wastewater containing Reactive Blue 4 by a bacterial consortium of Salmonella subterranea and Paenibacillus polymyxa

Anaerobic biodegradability of wastewater (3,000 mg CODcr/l) containing 300 mg/l Reactive Blue 4, with different co-substrates, glucose, butyrate and propionate by a bacterial consortium of Salmonella subterranea and Paenibacillus polymyxa, concomitantly with hydrogen production was investigated at 35°C. The accumulative hydrogen production at 3,067 mg CODcr/l was obtained after 7 days of incubation with glucose, sludge, the bacterial consortium. The volatile fatty acids, residual glucose and the total organic carbon were correlated to hydrogen obtained. Interestingly, the bacterial consortium possess decolorization ability showing approximately 24% dye removal after 24 h incubation using glucose as a co-substrate, which was about two and eight times those of butyrate (10%), propionate (12%) and control (3%), respectively. RB4 decolorization occurred through acidogenesis, as high volatile fatty acids but low methane was detected. The bacterial consortium will be the bacterial strains of interest for further decolorization and hydrogen production of industrial waste water.     

Additive Synergism between Asbestos and Smoking in Lung Cancer Risk: A Systematic Review and Meta-Analysis

Smoking and asbestos exposure are important risks for lung cancer. Several epidemiological studies have linked asbestos exposure and smoking to lung cancer. To reconcile and unify these results, we conducted a systematic review and meta-analysis to provide a quantitative estimate of the increased risk of lung cancer associated with asbestos exposure and cigarette smoking and to classify their interaction. Five electronic databases were searched from inception to May, 2015 for observational studies on lung cancer. All case-control (N = 10) and cohort (N = 7) studies were included in the analysis. We calculated pooled odds ratios (ORs), relative risks (RRs) and 95% confidence intervals (CIs) using a random-effects model for the association of asbestos exposure and smoking with lung cancer. Lung cancer patients who were not exposed to asbestos and non-smoking (A-S-) were compared with; (i) asbestos-exposed and non-smoking (A+S-), (ii) non-exposure to asbestos and smoking (A-S+), and (iii) asbestos-exposed and smoking (A+S+). Our meta-analysis showed a significant difference in risk of developing lung cancer among asbestos exposed and/or smoking workers compared to controls (A-S-), odds ratios for the disease (95% CI) were (i) 1.70 (A+S-, 1.31–2.21), (ii) 5.65; (A-S+, 3.38–9.42), (iii) 8.70 (A+S+, 5.8–13.10). The additive interaction index of synergy was 1.44 (95% CI = 1.26–1.77) and the multiplicative index = 0.91 (95% CI = 0.63–1.30). Corresponding values for cohort studies were 1.11 (95% CI = 1.00–1.28) and 0.51 (95% CI = 0.31–0.85). Our results point to an additive synergism for lung cancer with co-exposure of asbestos and cigarette smoking. Assessments of industrial health risks should take smoking and other airborne health risks when setting occupational asbestos exposure limits.     

Morphological and molecular profiling of Spirogyra from northeastern and northern Thailand using inter simple sequence repeat (ISSR) markers

Green algae, Spirogyra (Chlorophyta), are found in a wide range of habitats including small stagnant water bodies, rivers, and streams. Species identification of Spirogyra based on morphological characteristics has proven to be a difficult process. An accurate identification method is required to evaluate genetic variations. This study is aimed at investigating the molecular profiling of 19 samples of Spirogyra from northern and northeastern Thailand. The morphological characteristics of each sample were recorded, viz. cell dimensions (width and length), along with the number and arrangement of chloroplast spirals/pyrenoids. With regard to a correlation of the biological and ecological parameters, conductivity was clearly significantly related to the number of pyrenoids. While DO is negatively related to the number of chloroplast spirals. Molecular studies with 10 ISSR primers were amplified to examine the DNA fingerprints. Morphological characters were determined to be significantly different by revealing 5 traits (P < 0.05) for all specimens. In addition, the DNA markers of all specimens were investigated using 10 ISSR primers. The results show that the PCR technique amplified 108 fragments. An analysis of the DNA fragments grouped all samples by ISRR-PCR, which were then separated into two groups according to their distribution.     

Solid phase synthesis of novel asymmetric hydrophilic head cholesterol-based cationic lipids with potential DNA delivery

Twenty-four asymmetric divalent head group cholesterol-based cationic lipids were designed and synthesized by parallel solid phase chemistry. These asymmetric head groups composed of amino functionality together with trimethylamino, di(2-hydroxyethyl)amino or guanidinyl groups. Spacers between cationic heads and linker were both equal and unequal in length. These lipids were subjected to evaluation for DNA binding affinities by gel retardation assay and were screened for their transfection efficiency on HEK293 cells. Cationic lipids with equal chain length exhibited high transfection efficiency when polar part contained asymmetric polar heads. In contrast, lipids with unequal chain length exhibited high transfection efficiency when polar part contained symmetric heads. According to the optimal formulation, seven lipids exhibited higher transfection efficiency than the commercially available transfection agents, Effectene?, DOTAP and DC-Chol, to deliver DNA into PC3 human prostate adenocarcinoma cells. 3β-[N-(N′-Guanidinyl)-2′-aminoethyl)-N-(2-aminoethyl)carbamoyl] cholesterol (5) bearing amino and guanidinyl polar heads exhibited highest transfection efficiency with minimal toxicity. The morphology of active liposomes was observed by transmission electron microscopy (TEM) and size of liposomes were around 200–700 nm.     

Role of environmental conditions on the expression levels,glycoform pattern and levels of sialyltransferase for hFSH produced by recombinant CHO cells

A recombinant CHO cell line in which the expresison of human follicle stimulating hormone (hFSH) was under the control of the actin promoter was maintained in steady state perfusion cultures on a protein free medium. The level of expression of the hFSH was controlled by varying the steady state level of dissolved oxygen (10–90% of air saturation) and of sodium butyrate (0–1.5mM). Under these conditions, the specific productivity of hFSH (q_FSH) varied from 0.7 to 4.8 ng hFSH/10⁶ cells/h. As the specific productivity of hFSH increased, there was a shift in the FSH isoforms to the lower pI fractions, corresponding to increased sialic acid content. As the specific productivity of hFSH increased, shifting the isoform distribution towards the lower pI isoforms, that the sialyltransferase enzymic activity also increased.     

Structural characterization of sulfated arabinans extracted from Cladophora glomerata Kützing and their macrophage activation

Water-soluble sulfated heteropolysaccharides were extracted from Cladophora glomerata Kützing and fractionated by ion-exchange chromatography, which yielded two subfractions, F₁ and F₂. The crude and fractionated polysaccharides (F₁ and F₂) mostly consisted of carbohydrates (62.8–74.5%) with various amounts of proteins (9.00–17.3%) and sulfates (16.5–23.5%), including different levels of arabinose (41.7–54.4%), galactose (13.5–39.0%), glucose (0.80–10.6%), xylose (6.84–13.4%), and rhamnose (0.20–2.83%). Based on the size exclusion chromatography (SEC) profiles, the crude and fractions mainly contained one peak with shoulders having molecular weight (M_w) ranges of 358–1,501 × 10³. The F₁ fraction stimulated RAW264.7 cells to produce considerable amounts of nitric oxide and cytokines compared to the crude and F₂ fraction. The backbone of the most potent immunostimulating fraction (F₁) was α-(1→4)-L-arabinopyranoside with galactose and xylose residues as branches at O-2 position, and sulfates mainly at O-2 position as well.