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Pigmented spore-forming bacterial strains were isolated from the gastrointestinal tracts of chickens for screening for heat-stable carotenoid-producing strains that could be applied as feed supplements. Of the seven heat-stable pigmented isolates screened, only two, yellow Sporosarcina saromensis CH1 and red-orange Bacillus aquimaris CH9, produced pigments with typical carotenoid absorbance peaks (400–500 nm). The CH9 carotenoids exhibited higher scavenging activity (73.2%) of DPPH free radicals than the CH1 carotenoids (35.9%) and carotenoids of the reference B. indicus HU36 strain (78.4%), in comparison to 100% activity of acid ascorbic at 18.75 M as the standard. The CH9 strain produced high levels of carotenoids (439 g [g DW]-1) and formed nearly 100% spores, whereas the CH1 strain produced low levels of carotenoids (92 g [g DW]-1) and only achieved 30% sporulation. Chromatographic and spectral profiles of the carotenoids found in CH9 indicated the presence of as many as 11 different carotenoid types closely related to 1-HO-demethylspheroidene and keto/hydroxyl derivatives of  carotene. We successfully produced concentrated orange CH9 spore powder at a high concentration of 6.1 × 1011 CFU g-1; these spores were much more heat-stable (66% survival at 80°C for 20 min) than the reference B. indicus HU36 spores (9% survival at 50°C for 20 min). In conclusion, B. aquimaris CH9 is a promising probiotic carotenoid-producing strain, with heat-stable spores that should withstand the heat-treatment processing required for feed and food supplement production.

Oil spills in the sea are generally prevented in various ways, one of them is the bioaugmentation method through bacterial entrapment on sawdust carriers. The entrapment of bacteria is one of the bacterial immobilization techniques. The potential of bacterial consortium on sawdust is still not widely used, especially in long-term storage. The purpose of this study was to obtain the viability of hydrocarbonoclastic bacterial consortium on sawdust after 0, 7, and 41 days of storage. The bacterial consortium consists of Bacillus aquimaris, B. megaterium, B. pumilus, Halobacillus trueperi, and Rhodobacteraceae bacterium. The samples were tested by culturing the immobilized bacterial consortium of 0, 7, and 41 days on falcon tubes containing crude oil and seawater. The viability of the immobilized bacterial consortium was tested for 28 days (days 0, 7, 14, 21, and 28) by enriched the bacterial populations periodically. The viability test was also supported by the measurement of environmental parameters on the 1 st day and the 28 th day such as DO, pH, salinity and, temperature. The results show that bacterial consortium in all storage periods was viable on sawdust carriers which related to the high number of bacterial populations on the 28 th day. The most viable bacterial consortium on sawdust was the 0-day storage (9.59 x 10 8 CFU/ml) which was indicated by the increases phase at the end of the day. It was proved that the bacteria are still productive and could degrade petroleum hydrocarbons.