[ Objective] The study was to investigate the volatile components of secondary metabolites from M. alpine producing arachidonic acid and explore the changes in its metabolic pathway. [ Method] The air above M. alpine ...[ Objective] The study was to investigate the volatile components of secondary metabolites from M. alpine producing arachidonic acid and explore the changes in its metabolic pathway. [ Method] The air above M. alpine broth was extracted by solid-phase microextraction（SPME） during the post-exponential phase of growth and analyzed by GC-MS. [Result] 13 compounds were identified, 12 of which were sesquiterpenes with C15H24 formula and accounting for 99.62% of the complete compounds. Thujopsene-（ 12）, α-Guaiene and Aristolene were three most sesquiterpenes accounting for 10.66%, 33.69% and 34.85% of total content respectively. It can be sufficiently certified that sesquiterpene metabolic pathway existing in M. alpine. [ Coclusion] Metabolic flux of sesquiterpene pathway increased to improve its mass accumulation, because one or several key enzyme genes mutation in isoprene or sesquiterpene pathway enhanced their activities during induction of mutation from initial strain.展开更多
In this study,we presented the isolation and characterization of eight novel seco-guaianolide sesquiterpenoids(1-8)and two known guaianolide derivatives(9 and 10),from the aerial part of Achillea alpina L..Compounds 1...In this study,we presented the isolation and characterization of eight novel seco-guaianolide sesquiterpenoids(1-8)and two known guaianolide derivatives(9 and 10),from the aerial part of Achillea alpina L..Compounds 1-3 were identified as guaianolides bearing an oxygen insertion at the 2,3 position,while compounds 4-8 belonged to a group of special 3-nor guaianolide sesquiterpenoids.The structural elucidation of 1-8,including their absolute configurations,were accomplished by a combination of spectroscopic data analysis and quantum electronic circular dichroism(ECD)calculations.To evaluate the potential antidiabetic activity of compounds 1-10,we investigated their effects on glucose consumption in palmitic acid(PA)-mediated HepG2-insulin resistance(IR)cells.Among the tested compounds,compound 7 demonstrated the most pronounced ability to reverse IR.Moreover,a mechanistic investigation revealed that compound 7 exerted its antidiabetic effect by reducing the production of the pro-inflammatory cytokine IL-1β,which was achieved through the suppression of the NLRP3 pathway.展开更多
From the roots of Sanguisorba alpina, a new triterpenoid was isolated and identified as 2-isobutyryloxy-19α, 25-dihydroxyursa-1, 12-dien-28-oic acid by means of spectral methods, named as aipinic acid.
Mortierella alpina has been considered as the most effective producer of arachidonic acid(ARA)-rich oil. It was found that several methods could improve the percentage of ARA in total lipids successfully, as they acti...Mortierella alpina has been considered as the most effective producer of arachidonic acid(ARA)-rich oil. It was found that several methods could improve the percentage of ARA in total lipids successfully, as they activated the desaturation system on the endoplasmic reticulum. Additionally, in M. alpina the ARA exists in several forms, such as triacylglycerol(TAG), and diacylglycerol(DAG). These forms are caused by different acyltransferases and they determine the nutrient value of the microbial oil. However, few works revealed detailed fatty acid distribution among lipid classes, which to some extent impeded the accurate regulation in ARA accumulation. Herein, this paper gives information on the accumulation process of main lipid classes and the changes of fatty acid composition in these lipids during ARA accumulation period in M. alpina. The result demonstrates that TAG was the dominant component of the total lipids, and it is the main form for ARA storage. The ARA enrichment stage occurred during 168–192 h when the amount of total lipids maintained steady. Further analysis indicated that the newly formed ARA-TAG might come from the incorporation and modi fication of saturated and monounsaturated fatty acids in other lipid classes. This work could be helpful for further optimization of ARA-rich TAG production.展开更多
Background:The organic nitrogen source is one of the key factors affecting Mortierella alpina cell growth as well as arachidonic acid(ARA)production.The aim of the present work is to achieve an optimized recipe of org...Background:The organic nitrogen source is one of the key factors affecting Mortierella alpina cell growth as well as arachidonic acid(ARA)production.The aim of the present work is to achieve an optimized recipe of organic nitrogen source for ARA production by M.alpina by testing four organic nitrogen sources.Results:In the flasks,the results showed yeast extract or corn steep liquor were the most suitable sole nitrogen sources for biomass and ARA yield.In the bioreactor,a biomass of 17.5 g L^(-1)and an ARA yield of 2.7 g L^(-1)were achieved when using sole yeast extract,while cell autolysis was induced when using sole corn steep liquor;When using the combined nitrogen source with corn steep liquor and yeast extract at a 3:7 weight ratio,the biomass and ARA yield were significantly improved to 37 and 7.8 g L^(-1),respectively.Conclusions:This work evaluated whether using a mix of organic nitrogen sources could improve ARA production when scaling up from a flask to a bioreactor culture.The 3:7 ratio of corn steep liquor to yeast extract was quite favourable for large-scale ARA production,and as a result,this combination has great potential for improving fungal cultures.展开更多
To achieve high production of arachidonic acid(ARA)through industrial fermentation of Mortierella alpina,the correlation between metal ions,mycelium pellet morphology and ARA production was investigated.By adding diff...To achieve high production of arachidonic acid(ARA)through industrial fermentation of Mortierella alpina,the correlation between metal ions,mycelium pellet morphology and ARA production was investigated.By adding different metal ions to the culture medium,observing the morphological differences of mycelium pellet,total oil production and ARA content and established a correlation between them.The results showed that adding sodium ions increase the density of mycelium pellet,while reducing the diameter of mycelium pellet,resulting in a 41.59%increase in ARA production.Potassium ions,magnesium ions,calcium ions and iron ions slightly reduce the diameter of fungal hyphae and increase ARA production by 7.47%,17.81%,36.05%and 9.37%,respectively.At the same time,calcium ions promoted the branching growth of mycelium,which solve the problem of excessive free mycelium in fermentation broth within a certain concentration range.Zinc ions had a negative impact on bacterial growth,leading to the formation of mycelium clumps in the fermentation broth.Manganese ions and ferrous ions could transform the morphology of fungal mycelium into a smooth spherical surface,which was not conducive to the growth of M.alpina and the accumulation of oil.The comprehensive results showed that the optimal fermentation mycelium form for M.alpina was a dense central and loosely packed mycelium pellet.The yield of ARA was directly proportional to the density of mycelium pellet and inversely proportional to the diameter of mycelium pellet.展开更多
Arachidonic acid （ARA or AA）, one of the most important polyunsaturated fatty acids （PUFAs）, has various physiological activities and positive effects on human health. ARA production by Mortierella alpina has beco...Arachidonic acid （ARA or AA）, one of the most important polyunsaturated fatty acids （PUFAs）, has various physiological activities and positive effects on human health. ARA production by Mortierella alpina has become a hot topic in recent years, owing to that it is effective, safe and easy to control. How to improve ARA yield and purification efficiency is important to ARA production in M. alpina. Therefore, in this review, we summarized some methods to improve ARA yield： optimization of culture conditions, mycelium aging technologies and metabolic regulation, and the commonly used methods for ARA isolation and purification, to provide a theoretical basis for ARA production by M. alpina fermentation.展开更多
Mortierella alpina is a valuable source of arachidonic acid(ARA),with the majority being stored as triglycerides(TAG).The metabolism of TAG in M.alpina affects lipid composition and ARA accumulation,thereby determinin...Mortierella alpina is a valuable source of arachidonic acid(ARA),with the majority being stored as triglycerides(TAG).The metabolism of TAG in M.alpina affects lipid composition and ARA accumulation,thereby determining its nutritional quality.However,the molecular alterations of TAG in M.alpina remain unclear.To investigate lipid composition and ARA accumulation during the fermentation process of M.alpina ATCC 32222,we utilized techniques such as lipidomics,13C-NMR,and other analytical methods.This study demonstrated significant differences in the fatty acid composition and molecular alterations of TAG,diacylglyceride(DAG),and phosphatidylcholine(PC)during the fermentation process of M.alpina(p<0.05).During the cell growth stage,PC serves as the primary site for modifying fatty acids,allowing ARA and its precursors to concentrate at the sn-2 position of TAG.The lipid turnover stage represents a crucial period for the subsequent accumulation of ARA,with a significant increase in ARA content observed during this stage,particularly in TAG(20:4_20:4_20:4),DAG(20:4_20:4),and PC(20:4_20:4)species(p<0.05).The lipase inhibitor orlistat induces the disappearance of the lipid turnover stage,suggesting that the accumulation of ARA may be attributed to the reduced activity of lipase along with enzymes like lysophosphatidic acid acyltransferase.Increasing the activity of these enzymes will help to increase the ARA content and improve TAG structure.Additionally,conversion from 2 ARA-TAG to 3 ARA-TAG may represent a potential bottleneck limiting ARA production.Our findings provide valuable insights into mechanisms governing ARA accumulation in M.alpina.展开更多
基金Supported by the National Natural Science Foundation of China(20606018)the National Basic Research Program (also called 973Program)(2007CB707805)the Six Projects Sponsoring Talent Summits of Jiangsu Province~~
文摘[ Objective] The study was to investigate the volatile components of secondary metabolites from M. alpine producing arachidonic acid and explore the changes in its metabolic pathway. [ Method] The air above M. alpine broth was extracted by solid-phase microextraction（SPME） during the post-exponential phase of growth and analyzed by GC-MS. [Result] 13 compounds were identified, 12 of which were sesquiterpenes with C15H24 formula and accounting for 99.62% of the complete compounds. Thujopsene-（ 12）, α-Guaiene and Aristolene were three most sesquiterpenes accounting for 10.66%, 33.69% and 34.85% of total content respectively. It can be sufficiently certified that sesquiterpene metabolic pathway existing in M. alpine. [ Coclusion] Metabolic flux of sesquiterpene pathway increased to improve its mass accumulation, because one or several key enzyme genes mutation in isoprene or sesquiterpene pathway enhanced their activities during induction of mutation from initial strain.
基金supported by the National Natural Science Foundation of China(No.82003606)the Scientific and Technological Key Project in Henan Province(No.212102311093)the Scientific Research Nursery Project(No.MP2020-29).
文摘In this study,we presented the isolation and characterization of eight novel seco-guaianolide sesquiterpenoids(1-8)and two known guaianolide derivatives(9 and 10),from the aerial part of Achillea alpina L..Compounds 1-3 were identified as guaianolides bearing an oxygen insertion at the 2,3 position,while compounds 4-8 belonged to a group of special 3-nor guaianolide sesquiterpenoids.The structural elucidation of 1-8,including their absolute configurations,were accomplished by a combination of spectroscopic data analysis and quantum electronic circular dichroism(ECD)calculations.To evaluate the potential antidiabetic activity of compounds 1-10,we investigated their effects on glucose consumption in palmitic acid(PA)-mediated HepG2-insulin resistance(IR)cells.Among the tested compounds,compound 7 demonstrated the most pronounced ability to reverse IR.Moreover,a mechanistic investigation revealed that compound 7 exerted its antidiabetic effect by reducing the production of the pro-inflammatory cytokine IL-1β,which was achieved through the suppression of the NLRP3 pathway.
基金This work was supported by the National Natural Science Foundation of China.
文摘From the roots of Sanguisorba alpina, a new triterpenoid was isolated and identified as 2-isobutyryloxy-19α, 25-dihydroxyursa-1, 12-dien-28-oic acid by means of spectral methods, named as aipinic acid.
基金Supported by the National Science Foundation for Distinguished Young Scholars of China(21225626)the National Basic Research Program of China(2011CBA00800)+3 种基金the National Natural Science Foundation of China(21376002,21476111)the Natural Science Foundation of Jiangsu Province(BK20131405)the National High-Tech R&D Program of China(2014AA021703)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Mortierella alpina has been considered as the most effective producer of arachidonic acid(ARA)-rich oil. It was found that several methods could improve the percentage of ARA in total lipids successfully, as they activated the desaturation system on the endoplasmic reticulum. Additionally, in M. alpina the ARA exists in several forms, such as triacylglycerol(TAG), and diacylglycerol(DAG). These forms are caused by different acyltransferases and they determine the nutrient value of the microbial oil. However, few works revealed detailed fatty acid distribution among lipid classes, which to some extent impeded the accurate regulation in ARA accumulation. Herein, this paper gives information on the accumulation process of main lipid classes and the changes of fatty acid composition in these lipids during ARA accumulation period in M. alpina. The result demonstrates that TAG was the dominant component of the total lipids, and it is the main form for ARA storage. The ARA enrichment stage occurred during 168–192 h when the amount of total lipids maintained steady. Further analysis indicated that the newly formed ARA-TAG might come from the incorporation and modi fication of saturated and monounsaturated fatty acids in other lipid classes. This work could be helpful for further optimization of ARA-rich TAG production.
基金funded by grants from the Science and Technology Program of Xiamen,China(No.3502Z20153005)from the National High Technology Research and Development Program of China(No.2014AA021701).
文摘Background:The organic nitrogen source is one of the key factors affecting Mortierella alpina cell growth as well as arachidonic acid(ARA)production.The aim of the present work is to achieve an optimized recipe of organic nitrogen source for ARA production by M.alpina by testing four organic nitrogen sources.Results:In the flasks,the results showed yeast extract or corn steep liquor were the most suitable sole nitrogen sources for biomass and ARA yield.In the bioreactor,a biomass of 17.5 g L^(-1)and an ARA yield of 2.7 g L^(-1)were achieved when using sole yeast extract,while cell autolysis was induced when using sole corn steep liquor;When using the combined nitrogen source with corn steep liquor and yeast extract at a 3:7 weight ratio,the biomass and ARA yield were significantly improved to 37 and 7.8 g L^(-1),respectively.Conclusions:This work evaluated whether using a mix of organic nitrogen sources could improve ARA production when scaling up from a flask to a bioreactor culture.The 3:7 ratio of corn steep liquor to yeast extract was quite favourable for large-scale ARA production,and as a result,this combination has great potential for improving fungal cultures.
基金supported by the Scientific Research Fund Project of Education Department of Liaoning Province(LJKZZ20220060,LJKZ0514)Open Foundation of State Key Laboratory of Marine Food Processing&Safety Control(SKL202306).
文摘To achieve high production of arachidonic acid(ARA)through industrial fermentation of Mortierella alpina,the correlation between metal ions,mycelium pellet morphology and ARA production was investigated.By adding different metal ions to the culture medium,observing the morphological differences of mycelium pellet,total oil production and ARA content and established a correlation between them.The results showed that adding sodium ions increase the density of mycelium pellet,while reducing the diameter of mycelium pellet,resulting in a 41.59%increase in ARA production.Potassium ions,magnesium ions,calcium ions and iron ions slightly reduce the diameter of fungal hyphae and increase ARA production by 7.47%,17.81%,36.05%and 9.37%,respectively.At the same time,calcium ions promoted the branching growth of mycelium,which solve the problem of excessive free mycelium in fermentation broth within a certain concentration range.Zinc ions had a negative impact on bacterial growth,leading to the formation of mycelium clumps in the fermentation broth.Manganese ions and ferrous ions could transform the morphology of fungal mycelium into a smooth spherical surface,which was not conducive to the growth of M.alpina and the accumulation of oil.The comprehensive results showed that the optimal fermentation mycelium form for M.alpina was a dense central and loosely packed mycelium pellet.The yield of ARA was directly proportional to the density of mycelium pellet and inversely proportional to the diameter of mycelium pellet.
基金Supported by Natural Science Foundation of Yunnan Province(2016FB030)Young Academic and Technical Talent Program of Yunnan Province(2011CI027)~~
文摘Arachidonic acid （ARA or AA）, one of the most important polyunsaturated fatty acids （PUFAs）, has various physiological activities and positive effects on human health. ARA production by Mortierella alpina has become a hot topic in recent years, owing to that it is effective, safe and easy to control. How to improve ARA yield and purification efficiency is important to ARA production in M. alpina. Therefore, in this review, we summarized some methods to improve ARA yield： optimization of culture conditions, mycelium aging technologies and metabolic regulation, and the commonly used methods for ARA isolation and purification, to provide a theoretical basis for ARA production by M. alpina fermentation.
基金funded by the National Natural Science Founda-tion of China(32402040,32021005)Postdoctoral Fellowship Program of CPSF(No.GZC20230983)+1 种基金China Postdoctoral Science Foundation Funded Project(No.2023M741408)the program of‘Collaborative innovation center of food safety and quality control in Jiangsu Province’.
文摘Mortierella alpina is a valuable source of arachidonic acid(ARA),with the majority being stored as triglycerides(TAG).The metabolism of TAG in M.alpina affects lipid composition and ARA accumulation,thereby determining its nutritional quality.However,the molecular alterations of TAG in M.alpina remain unclear.To investigate lipid composition and ARA accumulation during the fermentation process of M.alpina ATCC 32222,we utilized techniques such as lipidomics,13C-NMR,and other analytical methods.This study demonstrated significant differences in the fatty acid composition and molecular alterations of TAG,diacylglyceride(DAG),and phosphatidylcholine(PC)during the fermentation process of M.alpina(p<0.05).During the cell growth stage,PC serves as the primary site for modifying fatty acids,allowing ARA and its precursors to concentrate at the sn-2 position of TAG.The lipid turnover stage represents a crucial period for the subsequent accumulation of ARA,with a significant increase in ARA content observed during this stage,particularly in TAG(20:4_20:4_20:4),DAG(20:4_20:4),and PC(20:4_20:4)species(p<0.05).The lipase inhibitor orlistat induces the disappearance of the lipid turnover stage,suggesting that the accumulation of ARA may be attributed to the reduced activity of lipase along with enzymes like lysophosphatidic acid acyltransferase.Increasing the activity of these enzymes will help to increase the ARA content and improve TAG structure.Additionally,conversion from 2 ARA-TAG to 3 ARA-TAG may represent a potential bottleneck limiting ARA production.Our findings provide valuable insights into mechanisms governing ARA accumulation in M.alpina.
