Different salinity effects on the mass cultivation of spirulina (Arthrospira platensis) using urea as nitrogen source in Oman and Malaysia

Mother earth is facing multitude of problems such as desertification, diminishing cultivation land and malnutrition. One way to overcome these problems is through cultivation of Spirulina (A. platensis). This paper focused on the different effects of salinity and comparative climate patterns to the mass production of A. platensis in Oman and in Malaysia. With extremely contrasting environment, A. platensis has unique ability to grow in both tropical (Malaysia) and arid (Oman) outdoor conditions. Mass cultivation has been carried out at different salinity 5, 15, 25 and 35 ppt for 10 days with triplicates in both countries. The total volume of culture in each tank and land photobioreactor was maintained at 100 L and 50L respectively. In Oman, the highest optical density (ABS) was 1.691 ± 0.099 at 5 ppt significantly different and higher than 25 and 35 ppt (p 0.05). While in Malaysia, the highest optical density (ABS) recorded with Spirulina dry weight was collected from Spirulina culture treatment with 5 ppt, 0.974 ± 0.052 was not significantly different from other salinity treatments (p > 0.05) and the dry weight at 0.575 ± 0.032 g L -1 was significantly different to 25 and 35 ppt (p < 0.05). Highest average mean ± SE of pH in Oman and Malaysia were recorded with salinity treatment of 15 ppt, 10.60 ± 0.058 and 10.20 ± 0.037

Comparison of phytoplankton diversity and succession between two small man-made lakes in Serdang, Selangor

Information on the relations between phytoplankton communities and the environment is limited for the man-made lakes in Malaysia. This paper presents the results of a study on the diversity and seasonal succession of phytoplankton in Seri Serdang Lake and Faculty of Engineering Lake conducted between November 2013 and February 2014. A total of 27 species from four phyla (Chlorophyta, Euglenophyta, Cyanobacteria, Bacillariophy ta) and 33 species belonging to Cyanobacteria, Chlorophyta, Bacillariophyta, Euglenophyta and Dinophyta were identified from Seri Serdang Lake and the Faculty of Engineering Lake, respectively. Chlorophyta were most dominant in both lakes. Highest number of species recorded was Monoraphidium sp. in Seri Serdang Lake and Pediastrum tetras in Faculty of Engineering Lake. Seri Serdang Lake had lower phytoplankton density (20 cells ml–1 to 396 cells ml–1) as compared to the Faculty of Engineering Lake (250 cells ml–1 to 300 cells ml–1). Although the distance between the two lakes is short, they do not share the same tributary probably leading to the observed differences in water quality, species diversity and succession pattern

Productivity and proximate analyses of Spirulina (Arthrospira platensis) in different floating water-based photobioreactor designs

Various concepts of photobioreactor (PBR) have been discovered scientists around the world. Though, only definite photobioreactor designs would be suitable for growing microalgae in a certain geographical climate outdoor condition. This study focused on developing simple floating water-based photobioreactor (PBR) without any computerized controlled systems. The aim of this study was to identify the chronology in developing best design overall for a photobioreactor. Major part of the design involved the aspect of the structure materials, shape and rigidness, whereas minor parts of the photobioreactors design includes the aeration placement, agitation or mixing, coloration corresponding to the high light intensity, temperature control, the size of the openings for the free exchange of gas and support for stable float on the water. Experiments performed would indicate these simple floating photobioreactors whether there are either significant or insignificant effects on the productivity of Arthrospira platensis (Spirulina) compared to the simple land based PBR especially under tropical climate.In outdoor condition in Malaysia, the weather patterns are extremely unexpected. Weather patterns that usually occurs can be categorized into three namely, first, humid or wet weather that have a high frequency of rain; mixed weather which has average frequency of rain occurrence, overcast with thick cloud layer and also relatively have high light intensity; finally, dry weather having less rain, often exposed to high temperatures and bright sunlight. Floating photobioreactor (PBR) has been designed in two distinct rigid shapes (Octagonal and Cylindrical) built using recycled water bottles, Polyethylene terephthalate (PET).While another form of simple floating PBR was designed more flexible as floating enclosure and was custom made from High Density Polyethylene (HDPE) materials. Simple land based PBR was prepared with High-density Polyethylene (HDPE) plastic bag, (25cm x 50cm). For every minor modification, 10 days of A. platensis cultivation inside all PBRs were conducted with daily monitoring of growth parameters. The expected outcome from this experiment shall anticipate that floating PBRs would gives higher yield in term of biomass dry weight and specific growth rate of cultured A. platensis in comparison of land based PBR. In any case, developing and third world countries could use simple floating PBRs for commercial applications instead of investing on impractical and complicated photobioreactor designs. For proximate analyses, the average total protein content (%) of A. platensis cultured in Cylindrical and Octagonal PBR under dry weather condition was higher significantly (p < 0.05) at 61.18±0.45 and 60.58±0.62 than other PBRs respectively. Total carbohydrate content (%) of A. platensis cultured in Cylindrical PBR (dry weather condition) was significantly (p < 0.05) higher at 26.71±1.43. While the lowest lipid content recorded in Flexible PBR, 0.66 ± 0.579% respectively. Highest scored by Cylindrical PBR, 7.883±0.28 under mix weather condition. The study indicated simple floating photobioreactor system for practical commercial cultivation system. Water based cultivation system has been seen promising compared to land based cultivation system. Several advantages were determined as more dry biomass and productivity of Spirulina were achieved compared to common practice of land based cultivation system. Moreover, this simple enclosed floating photobioreactor system may be an economical starter approach for modern farmers in order to maintain high quality, cleanliness and purity of Spirulina

Phytoplankton diversity in relation to different weather conditions in two urban made lakes

Many scientists have reported that global warming have significant impact on phytoplankton community, however, the impact of global warming on phytoplankton communities in suburban made lake is less understood. Therefor the objective of this study are to observe the effect of variable weather conditions on the diversity and succession of phytoplankton in mesotrophic lake (Seri Serdang) and oligotrophic lake (Engineering Faculty Lake). Samples were collected from surface water and species diversity (Shannon Weaver Diversity Index) was calculated. Daily weather and rain fall were recorded. A total of 65 species from five divisions (Chlorophyta, Euglenophyta, Cyanophyta, Bacillariophyta and Dinophyta) and 52 species belonging to six divisions (Chlorophyta, Cyanophyta, Bacillariophyta, Euglenophyta, Cryptophyta & Charophyta) were recorded from Engineering Faculty Lake and Seri Serdang Lake respectively. Division of Chlorophyta was found most dominant in both lakes during all the weeks (67%). The most dominant species in Faculty Engineering Lake was Microcystis aeruginosa during all weather conditions. Whereas, the most dominant species in Seri Serdang Lake during all weather conditions were Chlamydomonas reinhardtii, Planktothrix agardhii. The phytoplankton density was low during dry weather conditions for both lakes. The present finding suggested noticeable correlation between weather changes to the alteration of population density of phytoplankton

Phytoplankton diversity in relation to different weather conditions in two urban made lakes

Many scientists have reported that global warming have significant impact on phytoplankton community, however, the impact of global warming on phytoplankton communities in suburban made lake is less understood. Therefor the objective of this study are to observe the effect of variable weather conditions on the diversity and succession of phytoplankton in mesotrophic lake (Seri Serdang) and oligotrophic lake (Engineering Faculty Lake). Samples were collected from surface water and species diversity (Shannon Weaver Diversity Index) was calculated. Daily weather and rain fall were recorded. A total of 65 species from five divisions (Chlorophyta, Euglenophyta, Cyanophyta, Bacillariophyta and Dinophyta) and 52 species belonging to six divisions (Chlorophyta, Cyanophyta, Bacillariophyta, Euglenophyta, Cryptophyta & Charophyta) were recorded from Engineering Faculty Lake and Seri Serdang Lake respectively. Division of Chlorophyta was found most dominant in both lakes during all the weeks (67%). The most dominant species in Faculty Engineering Lake was Microcystis aeruginosa during all weather conditions. Whereas, the most dominant species in Seri Serdang Lake during all weather conditions were Chlamydomonas reinhardtii, Planktothrix agardhii. The phytoplankton density was low during dry weather conditions for both lakes. The present finding suggested noticeable correlation between weather changes to the alteration of population density of phytoplankton