Attached cultivation is a promising method for microalgal biomass production. Filamentous oleaginous microalga Tribonema minus(hereafter T. minus) has shown a remarkable potential for biofuel production in terms of it...Attached cultivation is a promising method for microalgal biomass production. Filamentous oleaginous microalga Tribonema minus(hereafter T. minus) has shown a remarkable potential for biofuel production in terms of its high lipid content. However, the strain has only been cultivated in suspended cultivation systems including open pond and closed photobioreactors. Here, we attempted to study the attached cultivation of T. minus, which might be helpful for its scale-up cultivation and industrial applications. As the results, the optimal conditions for T. minus growth in the attached biofilm are 200 μmol photons m^-2 s^-1 of light intensity and 5% of CO2, and the maximum biomass density of 223 g m^-2 has been achieved under the light intensity. The non-woven fabric as substratum was found as the best substratum in thin layer attached bioreactor, on which the average biomass productivity of T. minus is about(9.73 ± 2.19) g m^-2)d^-1. Furthermore, two attached bioreactor systems, rotary drum and rotation disc, were designed following the light dilution strategy and introduced into T. minus cultivation. The highest footprint areal biomass productivity of these two systems is 33 and 47.1 g m^-2 d^-1, respectively, much higher than that in suspended cultivation system. The results shows that T. minus can be cultured with attached cultivation method to improve its biomass productivity.展开更多
Filamentous microalgae from genus Tribonema are promising sustainable sources of omega-7 palmitoleic acid,but their ability to accumulate this compound varies among species and depends on the initial nitrogen concentr...Filamentous microalgae from genus Tribonema are promising sustainable sources of omega-7 palmitoleic acid,but their ability to accumulate this compound varies among species and depends on the initial nitrogen concentration(INC)supply.In this study,the palmitoleic acid accumulation capacities of five Tribonema species were examined under three different INCs to select the alga species with the highest production.Results showed that a high INC was associated with increased palmitoleic acid accumulation but led to decreased biomass concentration in all tested species.In particular,T.minus grown at 18 mmol L^(−1)INC had the highest palmitoleic acid content(20.72%of dry weight)and productivity(90.88 mg L^(−1)d−1).The combination of alkali metal freezing precipitation(AMFP)and urea complexation successfully isolated and enriched palmitoleic acid from T.minus and obtained a purity of 80.11%and a yield of 7.39 g(100 g)^(−1) of algal powder.The compound was identified as(9Z)-hexadecenoic acid(C16:1ω-7).Antibacterial activity evaluation for the highly concentrated palmitoleic acid(10 mg mL^(−1))against Streptococcus agalactiae revealed the formation of a 12.10 mm-diameter inhibition zone and the minimum inhibitory concentration of 31.25μg mL^(−1),indicating that palmitoleic acid is an effective antibacterial agent.This study is the first to report that palmitoleic acid derived from T.minus can antagonize S.agalactiae,which further broadens the potential application of Tribonema biomass in green aquaculture.展开更多
Eukaryotic photosystem I(PSI)is a multi-subunit pigment-protein supercomplex that consists of a core complex and multiple peripheral lightharvesting complexes I(LHCIs),which increases the light absorption capacity of ...Eukaryotic photosystem I(PSI)is a multi-subunit pigment-protein supercomplex that consists of a core complex and multiple peripheral lightharvesting complexes I(LHCIs),which increases the light absorption capacity of the core complex.Throughout the evolution of oxygenic photoautotrophs,the core subunits of PSI have remained highly conserved,while LHCIs exhibit significant variability,presumably to adapt to diverse environments.This study presents a 2.82Åresolution structure of PSI from the filamentous yellow-green alga Tribonema minus(Tm),a member of the class Xanthophyceae that evolved from red algae through endosymbiosis and is considered a promising candidate for biofuel production due to its high biomass and lipid content.Our structure reveals a supramolecular organization consisting of 12 core subunits and 13LHCIs,here referred to as Xanthophyceae lightharvesting complexes(XLHs),along with the arrangement of pigments within the Tm PSI-XLH supercomplex.A structural comparison between Tm PSI-XLH and PSI-LHCI from various red lineages highlights distinctive features of Tm PSI-XLH,suggesting that it represents a unique intermediate state in the PSI assembly process during the evolutionary transition from red algae to diatoms.Our findings advance the understanding of the molecular mechanisms responsible for energy transfer in Xanthophyceae PSI-XLH and the evolutionary adaptation of red lineages.展开更多
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Transformational Technologies for Clean Energy and Demonstration)(No.XDA21010211)the Shandong Provincial Natural Science Foundation (No.ZR2017QC007)the Youth Innovation Promotion Association, CAS。
文摘Attached cultivation is a promising method for microalgal biomass production. Filamentous oleaginous microalga Tribonema minus(hereafter T. minus) has shown a remarkable potential for biofuel production in terms of its high lipid content. However, the strain has only been cultivated in suspended cultivation systems including open pond and closed photobioreactors. Here, we attempted to study the attached cultivation of T. minus, which might be helpful for its scale-up cultivation and industrial applications. As the results, the optimal conditions for T. minus growth in the attached biofilm are 200 μmol photons m^-2 s^-1 of light intensity and 5% of CO2, and the maximum biomass density of 223 g m^-2 has been achieved under the light intensity. The non-woven fabric as substratum was found as the best substratum in thin layer attached bioreactor, on which the average biomass productivity of T. minus is about(9.73 ± 2.19) g m^-2)d^-1. Furthermore, two attached bioreactor systems, rotary drum and rotation disc, were designed following the light dilution strategy and introduced into T. minus cultivation. The highest footprint areal biomass productivity of these two systems is 33 and 47.1 g m^-2 d^-1, respectively, much higher than that in suspended cultivation system. The results shows that T. minus can be cultured with attached cultivation method to improve its biomass productivity.
基金supported by the Jiangsu Provincial Natural Science Foundation(No.BK20200734)the Hubei Provincial Natural Science Foundation(No.2021CFB224)+3 种基金the Engineering Research Center for Tropical and Subtropical Aquatic Ecological Engineering,Ministry of Education,Jinan University,P.R.China(No.2021A0401)the Research and Innovation Initiatives of Wuhan Polytechnic University(WHPU)(No.2021Y06)the Hubei Key Laboratory for Processing and Transformation of Agricultural Products(WHPU,China)(No.2020HBSQGDKFB17)the Sinopec Joint Program of China Petroleum and Chemical Corporation(No.ST18005-2).
文摘Filamentous microalgae from genus Tribonema are promising sustainable sources of omega-7 palmitoleic acid,but their ability to accumulate this compound varies among species and depends on the initial nitrogen concentration(INC)supply.In this study,the palmitoleic acid accumulation capacities of five Tribonema species were examined under three different INCs to select the alga species with the highest production.Results showed that a high INC was associated with increased palmitoleic acid accumulation but led to decreased biomass concentration in all tested species.In particular,T.minus grown at 18 mmol L^(−1)INC had the highest palmitoleic acid content(20.72%of dry weight)and productivity(90.88 mg L^(−1)d−1).The combination of alkali metal freezing precipitation(AMFP)and urea complexation successfully isolated and enriched palmitoleic acid from T.minus and obtained a purity of 80.11%and a yield of 7.39 g(100 g)^(−1) of algal powder.The compound was identified as(9Z)-hexadecenoic acid(C16:1ω-7).Antibacterial activity evaluation for the highly concentrated palmitoleic acid(10 mg mL^(−1))against Streptococcus agalactiae revealed the formation of a 12.10 mm-diameter inhibition zone and the minimum inhibitory concentration of 31.25μg mL^(−1),indicating that palmitoleic acid is an effective antibacterial agent.This study is the first to report that palmitoleic acid derived from T.minus can antagonize S.agalactiae,which further broadens the potential application of Tribonema biomass in green aquaculture.
基金funded by the National Key R&D Program of China(2022YFC2804400)the National Natural Science Foundation of China(32371269 and 32470247)the National Laboratory of Biomacromolecules(2024kf05)。
文摘Eukaryotic photosystem I(PSI)is a multi-subunit pigment-protein supercomplex that consists of a core complex and multiple peripheral lightharvesting complexes I(LHCIs),which increases the light absorption capacity of the core complex.Throughout the evolution of oxygenic photoautotrophs,the core subunits of PSI have remained highly conserved,while LHCIs exhibit significant variability,presumably to adapt to diverse environments.This study presents a 2.82Åresolution structure of PSI from the filamentous yellow-green alga Tribonema minus(Tm),a member of the class Xanthophyceae that evolved from red algae through endosymbiosis and is considered a promising candidate for biofuel production due to its high biomass and lipid content.Our structure reveals a supramolecular organization consisting of 12 core subunits and 13LHCIs,here referred to as Xanthophyceae lightharvesting complexes(XLHs),along with the arrangement of pigments within the Tm PSI-XLH supercomplex.A structural comparison between Tm PSI-XLH and PSI-LHCI from various red lineages highlights distinctive features of Tm PSI-XLH,suggesting that it represents a unique intermediate state in the PSI assembly process during the evolutionary transition from red algae to diatoms.Our findings advance the understanding of the molecular mechanisms responsible for energy transfer in Xanthophyceae PSI-XLH and the evolutionary adaptation of red lineages.
