Haloarchaea represents a unique group of microorganisms that have adapted to thrive in high-salt environments.These microbes produce distinctive biomolecules,some of which exhibit extraordinary properties.One such bio...Haloarchaea represents a unique group of microorganisms that have adapted to thrive in high-salt environments.These microbes produce distinctive biomolecules,some of which exhibit extraordinary properties.One such biomolecule is bacterioruberin,a prominent red-pigmented C50 carotenoid commonly found in halophilic archaea,renowned for its antioxidant properties and potential as a functional resource.This study aimed to enhance the culture conditions for optimal production of C50 carotenoids,primarily bacterioruberin,using“Haloferax marinum”MBLA0078.The optimization process involved a combination of one-factor-at-a-time(OFAT)and statistical methodology.Under OFAT-optimized conditions,fed-batch fermentation,and response surface methodology(RSM)optimization,carotenoid production reached 0.954 mg/L,2.80 mg/L,and 2.16 mg/L,respectively,in a 7-L laboratory-scale fermenter.Notably,RSM-optimized conditions led to a 12-fold increase in productivity(0.72 mg/L/day)compared to the basal DBCM2 medium(0.06 mg/L/day).These findings suggest that strain MBLA0078 holds significant promise for commercial-scale production of bacterioruberin.展开更多
Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of bio...Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of biological functions. Ten red colordes were isolated from brine water in a saltem crystaltizer pond of the Hangu Saltworks, China. 16S rRNA gene sequence analysis showed that the colonies belonged to the extremely halophilic archaea genera Halobacterium and Halorubrum. Two representative strains, Halobacterium strain SP-2 and Halorubrum strain SP-4, were selected for further study on the phenotypic characteristics and effects of salinity and pH on accumulation and composition of pigments in their cells. The archaeal strains were isolated and grown in a culture medium prepared by dissolving yeast extract （10 g/L） and acid-hydrolyzed casein （7.5 g/L） into brine water obtained from a I.ocal salt pond. Their optimum salinity and pH for growth were 250 and 7, respectively, although pigment accumulation （OD490/ mL broth） was highest at pH 8. In addition, at 150-300 salinity, increasing salinity resulted in decreasing pigment accumulation. Analysis of the UV-Vis spectrum, TLC and HLPC chromatograms showed that C50 carotenoid bacterioruberin is the major pigment in both strains.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(2022R1F1A1062699).
文摘Haloarchaea represents a unique group of microorganisms that have adapted to thrive in high-salt environments.These microbes produce distinctive biomolecules,some of which exhibit extraordinary properties.One such biomolecule is bacterioruberin,a prominent red-pigmented C50 carotenoid commonly found in halophilic archaea,renowned for its antioxidant properties and potential as a functional resource.This study aimed to enhance the culture conditions for optimal production of C50 carotenoids,primarily bacterioruberin,using“Haloferax marinum”MBLA0078.The optimization process involved a combination of one-factor-at-a-time(OFAT)and statistical methodology.Under OFAT-optimized conditions,fed-batch fermentation,and response surface methodology(RSM)optimization,carotenoid production reached 0.954 mg/L,2.80 mg/L,and 2.16 mg/L,respectively,in a 7-L laboratory-scale fermenter.Notably,RSM-optimized conditions led to a 12-fold increase in productivity(0.72 mg/L/day)compared to the basal DBCM2 medium(0.06 mg/L/day).These findings suggest that strain MBLA0078 holds significant promise for commercial-scale production of bacterioruberin.
基金Supported by the International Cooperation Research Program of the Ministry of Science&Technology of China(No.2010DFA32300)the Natural Science Foundation of Tianjin(No.13JCZDJC28700)
文摘Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of biological functions. Ten red colordes were isolated from brine water in a saltem crystaltizer pond of the Hangu Saltworks, China. 16S rRNA gene sequence analysis showed that the colonies belonged to the extremely halophilic archaea genera Halobacterium and Halorubrum. Two representative strains, Halobacterium strain SP-2 and Halorubrum strain SP-4, were selected for further study on the phenotypic characteristics and effects of salinity and pH on accumulation and composition of pigments in their cells. The archaeal strains were isolated and grown in a culture medium prepared by dissolving yeast extract （10 g/L） and acid-hydrolyzed casein （7.5 g/L） into brine water obtained from a I.ocal salt pond. Their optimum salinity and pH for growth were 250 and 7, respectively, although pigment accumulation （OD490/ mL broth） was highest at pH 8. In addition, at 150-300 salinity, increasing salinity resulted in decreasing pigment accumulation. Analysis of the UV-Vis spectrum, TLC and HLPC chromatograms showed that C50 carotenoid bacterioruberin is the major pigment in both strains.
