Commercial fish hatchery generates waste both organic and inorganic; the sources are primarily from uneaten food and fish feces. Conventional methods of treating hatchery wastes will increase the operating cost and become extra burden in production. It is necessary to develop a new research application of this nonconventional resource and reduce the negative impacts of hatchery waste on the environment. The whole project is to utilize hatchery waste through bioprocess for probiotic fortified live feed production. In this study, the chemical composition of hatchery waste was determined to understand the suitability waste to get value-added derived products through bioprocess. Composite samples were collected everyday and dried in an oven at a temperature of 65˚C until complete dryness. Dried samples were mixed well and grinded into fine powder. The analytical parameters like total solids, ammonium nitrogen, nitrite, nitrate and phosphate were determined from the freshly collected samples. Total nitrogen, total phosphorus and total potassium were determined from the dry samples. Total solids, ammonium nitrogen, nitrite, nitrate and phosphate-phosphorus were observed in the ranged from 75-82 mg/L, 0.25-8.5 mg/L, 0.05-1.9 mg/L, 0.04-6.7 mg/L and 4.1-16.7 mg/L respectively. On the other hand, the mean content of 3.75% total nitrogen, 1.80% total phosphorus and 0.15% potassium were determined in dry hatchery wastes. The analytical parameters are useful and demonstrate that the nutrients in both fresh and dry waste will be supportive for the growth of microbes in the bioprocess system.

Sustainable use of palm oil mill effluent (POME) has been the major focus in the recent development in palm oil industry due to the fact that environmental issue brought by POME. The purpose of this study was to determine the optimum incubation period of purple non-sulphur bacterium (PNSB) in reduction of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) in settled POME and to determine the dry cell weight, TN, TP and cell yield of PNSB. Pure isolate of Rhodobacter sphaeroides strain UMSFW1 was cultured in settled POME under anaerobic condition at 2500 lux illumination on light intensity at a temperature of 30˚C ± 2˚C for 144-h. Parameters such as COD (mg/L), dry cell biomass (g/L), TP (mg/L) and TN (mg/L) in settled POME and bacterial cells were analyzed. A total reduction of TN (43.9%) in settled POME and a total increase of TN (43.2%) in bacterial cell were recorded at the end of experiment. At the same time the reduction of 51.5% chemical oxygen demand was determined from the POME. The highest dry cell weight of 2.44 g/L with cell yield 0.39 (mg/cell/mg COD) was achieved at the end of experiment. A total 24.7% of TP reduction in settled POME was achieved in 144-h culture, but while a maximum 10% of TP in bacterial cell was achieved in 48-h culture. This study shows that PNSB Rhodobacter sphaeroides strain UMSFW1 grows well by using settled POME as substrate and is capable to remove TN in the settled POME and assimilate into bacterial biomass. This study could provide us a further insight in the nutrient removal and COD removal in the bioremediation process by bacterium Rhodobacter sphaeroides strain UMSFW1.

Fish wastes are the discarded parts include the internal organs, viscera, bones, trimmings, tails, fins and skin of fishes. These discarded portions while disposing of cause major environmental damage. Usually, the discarded parts of fishes are ground into fishmeal for livestock and aquaculture feed. This study was undertaken to explore biodiesel production based on the fatty acids composition. The fish waste sample was collected from Kota Kinabalu, Sabah fish market. The sample was drained for excess water and oven-dried at 55˚C -60˚C for complete dryness. Crude oils were extracted in petroleum ether in Soxhlet extraction method. Methylation of the extracted crude fish oil was carried out to yield fatty acid methyl esters (FAME). The FAME was analyzed by GCMS system and the reference to NIST library was used to identify the fatty acids present in the FAME. A total of 21 fatty acids were identified that composed of 53.53% saturated fatty acids (SFA), 22.1% monounsaturated fatty acid (MUFA) and 24.37% polyunsaturated fatty acids (PUFA). The important fatty acids [myristic acid (C14:0), palmitic acid (C16:0), palmitoleic acid (C16:1), oleic acid (C18:1), linoleic acid (C18:2), linolenic acid (C18:3), docosapentaenoic acid (C22:5) and docosahexaenoic acid (C22:6)] found in fish oil indicated the potentiality of biodiesel production if fish waste was stocked. The highest percentage of SFA causes higher viscosity, cetane number and density and hence these properties of biodiesel produced from the fish waste are expected to be high. Therefore, the fish waste has high potential of fatty acid in FAME to produce biodiesel through transesterification process.

Purple non-sulfur bacteria (PNSB) are well known for their ability in transforming organic substrates for their own source of nutrients. The nutritional values of leafy vegetable waste could be improved through bioconversion with PNSB. This study was conducted to access nutritional status of leafy vegetable waste bio-converted product and efficacy of derived product as aquaculture feed supplement. Proximate compositions of bio-converted leafy vegetable wastes were improved after 6 days with 30% inoculums of Afifella marina strain ME (KC205142). The crude proteins (%) and ashes (%) in derived product was increased to 51.7% and 19.6% respectively. On the other hand, the fiber (%) in the bio-converted derived product was decreased by 21%. During feeding trial in Tilapia (Oreochromis niloticus), no significant differences were observed in the feed intake (g/fish/day), but significant differences were observed in the value of feed conversion ratio and weight gain (%) among the used diets. However, lower ingestion rate (g/d/fish) and better feed conversion ratio were obtained while fishes were fed with diet composed of commercial feed mixed with 5% of the bio-converted product. The higher ingestion rate (g/d/fish) and lower feed conversion ratio were observed with only commercial diet. There observed no significant differences in the ingestion rate (g/d/fish) and FCR values among the diet composed of commercial feed with 5% (D5) and 10% (D10) of the bio-converted product. The derived bio-converted product can be a promising approach to open new market segment in aquafeed industry.

Purple Non-Sulfur Bacteria (PNSB), also known as phototrophic bacteria are widely distributed in both freshwater and marine environment and capable to grow in wide range of substrates. In this study, Bacterium Rhodobacter sphaeroides strain UMS2, a freshwater isolate was used in this study in utilization of fish hatchery waste. This study was conducted to determine the nutritional values of bioprocess product that was grown in fish hatchery waste. Finally, the waste bio-converted product was used as feed supplement to monitor the growth performance of live feed Tubifex spp. Inoculum of Rhodobacter sphaeroides strain UMS2 was developed in 112 synthetic media and 48-h culture of 30% (v/v) inoculum was used in fish hatchery waste during the bioprocess. The nutritional values of bio-converted product, except total ash (%), were not significantly improved with 30% (v/v) inoculum of Rhodobacter sphaeroides, strain UMS2. Feeding trial in bloodworm (Tubifex spp.) with bioconversion product conducted for 15 days to monitor growth (w/v) of live feed. Initial growth 1.42 ± 0.001 g/L of Tubifex spp. was stocked in 15 × 75 × 15 cm plastic tray connected with recirculated system. Tubifex spp. was observed to be comparatively higher (1.55 ± 0.12 g/L) while fed in the product that contained bacterium than the growth (1.44 ± 0.15 g/L) of Tubifex spp. fed in the bioconversion product of without bacterium. The inoculums size (30%) of bacterium not enough to support the growth of Rhodobacter sphaeroides, strain UMS2 in the bioconversion process to improve the nutritional values. However, while used as feed supplement it improved the growth performance of the Tubifex spp. So, bacterium Rhodobacter sphaeroides, strain UMS2 has potentiality to be used as feed supplement in the production of live feed.