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Blue economy, the sustainable and effective use of ocean resources for economic growth, is a major challenge to coastal communities. Marine macroalgae are potentially sustainable feedstock for future food, materials, chemicals, and fuels. For seaweed biorefinery, the fractionation of the biomass to co-produce multiple products is crucial in the efficient valorization of the marine biomass. In this work, we developed a protocol for co-production of six different products from the green macroalga Ulva ohnoi using green extraction methods. A total of 90.31 ± 1.94% of the initial biomass was recovered in separated products. The fraction of the recovered products from initial dry weight biomass was 45.42 ± 1.91% salts, 3.67 ± 1.38% starch, 3.81 ± 1.26% lipids, 13.88 ± 0.40% ulvan, 14.83 ± 1.06% proteins, and 8.70 ± 1.87% cellulose. A potential revenue analyses, based on these experimental data and current market prices, suggests that total the revenue fluctuates between US$1.56 and US$3.93 kg−1 of dry biomass and depends on recovered products fraction in the seaweed biomass and products market value. [ABSTRACT FROM AUTHOR]

Subcritical water hydrolysis and carbonization of the biomass are an emerging green technology for seaweed biomass processing. In this work, a novel approach for co-generation of two energy streams from seaweed biomass (fermentable sugars and solid hydrochar) with subcritical water from a green macroalgae Ulva sp. was developed. It was found that for the released of glucose, xylose, rhamnose, fructose, and galactose, the process temperature is the most significant parameter, followed by salinity, solid load, and treatment time. For the formation of fermentation inhibitor 5-hydroxymethylfurfural (5-HMF), temperature also was the most important parameter, followed by residence time, salinity, and solid load. The optimum parameters for maximal release of total sugars under minimum formation of 5-HMF were 170 °C (800 kPa abs.), 5% solid loading, 40 min residence time, and 100% salinity. The hydrochar yield was 19.4% and hydrochar high heating value was 20.2 ± 1.31 MJ kg−1. These results provide new detailed information on the subcritical hydrolysis and carbonization of Ulva sp. biomass and show co-production of fermentable monosaccharides and hydrochar. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa-an opportunistic pathogen, perhaps best known for chronic lung infections, produces wide range of pigments that possess specific activities which either assist the organism's survival or bring about changes within host. A similar blue-green diffusible pigment producing P. aeruginosa was isolated from dug-well water, so as to extract 1-hydroxyphenazine from its crude pigment. The compound was purified from the crude pigment using column chromatography followed by a preparative thin layer chromatography that showed a single yellow spot. Further molecular characterisation of the purified component was carried out using UV-Vis spectrophotometer, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy and mass spectroscopy which showed respective peaks corresponding to 1-hydroxyphenazine. Biological characterisation using in vitro assays revealed that 1-hydroxyphenazine showed anti-bacterial activity only against Bacillus sp. and a concentration of 30 µg/ml induced noticeable morphological alteration in A549 human lung adenocarcinoma cells followed by cell death after 48 h. Thus, such active components within bacterial pigments can be characterized and used as possible anti-bacterial or anti-cancer agents. [ABSTRACT FROM AUTHOR]