Macroalgal susceptibility to grazing by herbivore fish Siganus spp. at Gulf of Mannar reef,Indian Ocean

Environmental Biology of Fishes - Enhancing the herbivore fish stock is envisaged as a mitigation tool to reverse the macroalgal dominance in a coral reef environment. However, identifying the key...     

Roseovarius azorensis sp. nov., isolated from seawater at Espalamaca,Azores

A Gram-negative, motile, non-spore forming, rod shaped aerobic bacterium, designated strain SSW084^T, was isolated from a surface seawater sample collected at Espalamaca (38°33′N; 28°39′W), Azores. Growth was found to occur from 15 to 40 °C (optimum 30 °C), at pH 7.0–9.0 (optimum pH 7.0) and with 25–100 % seawater or 0.5–7.0 % NaCl in the presence of Mg²⁺ and Ca²⁺; no growth was found with NaCl alone. Colonies on seawater nutrient agar were observed to be punctiform, white, convex, circular, smooth, and translucent. Strain SSW084^T did not grow on Zobell marine agar and tryptic soy agar even when seawater supplemented. The major respiratory quinone was found to be Q-10 and the G + C content was determined to be 61.9 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain SSW084^T belongs to the genus Roseovarius and that its closest neighbours are Roseovarius tolerans EL-172^T, Roseovarius mucosus DFL-24^T and Roseovarius lutimaris 112^T with 95.7, 95.4 and 95.3 % sequence similarity respectively. The remaining species of Roseovarius showed <95 % similarity. The polar lipids of strain SSW084^T were determined to be phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, an unidentified lipid and one unidentified aminolipid. The major fatty acids identified were identified as C_18:1 ω7c (52.5 %) and C_16:0 (13.8 %). On the basis of phenotypic, molecular and chemotaxonomic characteristics, strain SSW084^T is considered to represent a novel species of the genus Roseovarius, for which Roseovarius azorensis sp. nov is proposed. The type strain is SSW084^T (=KCTC 32421^T = MTCC 11812^T).     

Laccase treatment of recycled blue dyed paper: physical properties and fiber charge

Recycled blue colored paper was treated with laccase under various combinations of physical and chemical parameters including enzyme concentration, temperature, oxygen, and reaction time. Laccase treatment of recycled dyed pulp increased acid group content, tear index, tensile index, and color removal in a dose-dependent manner. Lengthening the treatment time from 2 to 4 h was beneficial to acid group content (12% increase), dye removal, and tensile index but had a detrimental 8% decrease on the tear index. A higher reaction temperature (65 vs. 45 degrees C) had a beneficial effect on acid group content (+31%), and tensile index (+26%) and a slightly negative effect on tear index (-5%), but significantly reduced the ability of laccase to remove color. Comparison of reactions subjected to different levels of oxygen supplementation showed the greatest beneficial effect for laccase treatment with slow oxygen bubbling. The experimental results indicate that laccase treatment increases fiber carboxylic acid content and tensile strength, in addition to reducing the color of the enzyme treated paper.