[Objectives]To analyze the gene structure of the protein that predicts 6-hydroxymellein synthase of Aspergillus terreus and predict the characteristics and functions of the protein structure encoded by the gene.[Metho...[Objectives]To analyze the gene structure of the protein that predicts 6-hydroxymellein synthase of Aspergillus terreus and predict the characteristics and functions of the protein structure encoded by the gene.[Methods]Various information analysis tools in NCBI,CBS and ExPASy websites were adopted.[Results]The QODIPO gene had a full length of 2954 bp,with 952 amino acids in the coding area,and QODIPO had the highest homology with the hypothetical protein ATETN484_0003008800.The molecular weight of QOD1PO protein was 105040.56,the theoretical isoelectric point(pl)was 5.69 and the grand average of hydropathieity was-0.242.It was speculated that QODIPO was an unstable and non-secretory hydrophilic protein located in cytoplasm without transmembrane domain or signal peptide.It could be predicted that the secondary structure of QODIPO encoding protein consisted mainly of random coil,α-helix and a PKS-DH anhydrase domain.[Conclusions]The results will lay a theoretical foundation for cloning and expression of 6-hydroxymellein synthase and further understanding of its activity and function.展开更多
The effect of ultraviolet(UV)radiation and biocide benzalkonium chloride(BKC)on fungal-induced corrosion of AA7075 induced by Aspergillus terreus(A.terreus)was deeply studied using analysis of biological activity,surf...The effect of ultraviolet(UV)radiation and biocide benzalkonium chloride(BKC)on fungal-induced corrosion of AA7075 induced by Aspergillus terreus(A.terreus)was deeply studied using analysis of biological activity,surface analysis,and electrochemical measurements.Results demonstrated that the planktonic and sessile spore concentrations decline by more than two orders of magnitude when UV radiation and BKC are combinedly used compared with the control.UV radiation can inhibit the biological activity of A.terreus and influence the stability of passive film of AA7075.Except for direct disinfection,the physical adsorption of BKC on the specimen can effectively inhibit the attachment of A.terreus.The combination of UV radiation and BKC can much more effectively inhibit the corrosion of AA,especially pitting corrosion,due to their synergistic effect.The combined application of UV radiation and BKC can be a good method to effectively inhibit fungal-induced corrosion.展开更多
Lovastatin production by Aspergillus terreus ATCC 20542 in solid-state fermentation (SSF) was studied. Various substrates were used to evaluate the ability ofA. terreus to produce lovastatin. The results showed that...Lovastatin production by Aspergillus terreus ATCC 20542 in solid-state fermentation (SSF) was studied. Various substrates were used to evaluate the ability ofA. terreus to produce lovastatin. The results showed that either rice or wheat bran was suitable substrate for lovastatin production in SSF. The maximum yield of lovastatin (2.9 mg/g dry substrate) using rice as substrate was achieved after incubating for 11 d at the following optimized process parameters: 50%-60% initial moisture content, pH 5.5, incubation temperature 28 ℃.展开更多
Cassava (Manihot esculenta, Crantz) is one of the most important food plants in West Africa. Its peels are made up of cellulose, hemicellulose and lignin. This lignocellulolytic biomass can be converted using microbia...Cassava (Manihot esculenta, Crantz) is one of the most important food plants in West Africa. Its peels are made up of cellulose, hemicellulose and lignin. This lignocellulolytic biomass can be converted using microbial enzymes to fermentable sugars which have wide range of biotechnological relevance in many fermentation processes. The aim of this study is to screen filamentous fungi from decaying cassava peels that are good producers of xylanases and cellulases. Decaying parts of cassava peels were obtained and brought to the laboratory for further work. Fungi were isolated, identified and screened for cellulase and xylanase production. Isolate with highest frequency of occurrence and enzyme production was identified using phenotypic and molecular method. Optimisation of growth conditions for enzymes production was monitored using the DNSA method, also saccharification of cassava peel were carried out using the enzymes obtained from the isolate. Aspergillus terreus KJ829487 was the predominant fungus. It produces cellulases and xylanases optimally at 40°C, pH 6 and 8, utilising carboxymethylcellulose (CMC) or xylose and yeast extracts as its carbon and nitrogen sources respectively. Saccharification of the peels yielded 584 mg/L glucose, 78 mg/L xylose and 66 mg/L rhamnose. Aspergillus terreus KJ829487 obtained from cassava peels have the ability to produce high concentration cellulases and xylanases which effectively hydrolysed the lignocelluloses’ biomass to fermentable sugars.展开更多
L-asparaginase is a chemotherapeutic drug used in the treatment of lymphoblastic leukemia. In the present study, the extracellular L-asparaginase produced by strain (PC-1.7A) of Aspergillus terreus was purified, chara...L-asparaginase is a chemotherapeutic drug used in the treatment of lymphoblastic leukemia. In the present study, the extracellular L-asparaginase produced by strain (PC-1.7A) of Aspergillus terreus was purified, characterized, and modified with polyethylene glycol. Moreover, its antiproliferative activity was evaluated. The apparent molecular weight of the enzyme was found to be 136 kDa. The optimal pH and temperature for the enzyme were 9.0℃ and 40℃, respectively. The enzyme retained 100% of the activity at 40℃ for 120 min. Pegylated L-asparaginase was more thermostable and more resistant to trypsin than native enzyme. Native L-asparaginase against human normal cells did not show cytotoxicity. However, in the leukemia cell lines RS4;11 and HL60 the antiproliferative effects of native L-asparaginase were observed after 96 and 72 h of incubation, respectively. For the first time, an L-asparaginase from fungus was evaluated as an antitumor agent in human cells lines and further investigations should be conducted to improve the knowledge about this enzyme.展开更多
Itaconic acid is commercially produced by the cultivation of Aspergillus terreus using starch hydrolysate as carbon source. The degree of hydrolysis had a great influence on itaconic acid production which was suitable...Itaconic acid is commercially produced by the cultivation of Aspergillus terreus using starch hydrolysate as carbon source. The degree of hydrolysis had a great influence on itaconic acid production which was suitable when corn starch was saccharified at 35 DE. The α-amylase was sufficient to drive the starch hydrolysis to the degree. The agar plate assay with LiCl treatment provided a rapid, simple and unequivocal method for screening large numbers of colonies for itaconic acid producing strains. It was learned by experience that the strains on the plates with thick hyphae and light-colored spores often accompanied high itaconic acid production. A strain, designated Ast165, producing itaconic acid with a high yield, was successfully obtained by directional breeding of metabolic end products resistant strains. The itaconic acid concentration produced by Ast165 was 53.8 g/l from 100 g/l of starch hydrolysate in shake flasks. The conversion rate was 61.3%, which was the highest value found in tests.展开更多
RAPD was used to examine the genetic variability among five isolates of Aspergillus terreus spp.. Two random primers were selected for the RAPD assay PG01–5’ CAGGTGTTGC 3’ and PG02–5’ CTGGACAGAC 3’ (Progen Techn...RAPD was used to examine the genetic variability among five isolates of Aspergillus terreus spp.. Two random primers were selected for the RAPD assay PG01–5’ CAGGTGTTGC 3’ and PG02–5’ CTGGACAGAC 3’ (Progen Technologies). The characterization of Aspergillus terreus species have been mostly applied on the basis of morphology, phenotype and physiology. DNA Polymorphisms are based on differences in DNA sequences and have advantages over protein polymorphisms. But morphological characterization besides molecular tools will remain a basic and powerful key in the identification of Aspergillus terreus species. The objective of the present study was to isolate the fungal contaminants from dried grapes and compare the genomic profile of the Aspergillus terreus speices isolated from the dried grapes, through RAPD analysis. In the present study with primer PG 01 four different discriminations was there among the A. terreus isolates. There was a homology of genotype between the isolates 1 & 3. And with primer PG 02 four different discriminations were there and there was a homology between 1 & 3. The predominant type was type I in primer I & II. The other isolates belonged to 2, 3 and 4. No similarity was detected for isolates 3, 4 and 5 indicating great genomic diversity of A. terreus.展开更多
The objective of this study is to improve the production of L-DOPA from fungal source like Aspergillus terreus that can be further used to large-scale commercial production of this important drug from microbial source...The objective of this study is to improve the production of L-DOPA from fungal source like Aspergillus terreus that can be further used to large-scale commercial production of this important drug from microbial sources. L-DOPA, a dopamine precursor that can pass the blood-brain barrier, is presently the drug of choice for Parkinson's disease. Microbial production and isolation of L-DOPA from natural sources is yet to be achieved an economical process. In this study, the mycelial pellets ofAspergillus terreus 104 were entrapped in 2% calcium alginate and were studied for their capacity for L-3, 4-dihydroxyphenylalanine production. Results showed that the immobilized pellets produced L-DOPA to the extent of 0.74 mg·G^-1 biomass while the free pellets produced 0.8 mg·G^-1 biomass. Further, storage of immobilized pellets for 96 h at 4 ℃ resulted in the reduction of the original L-DOPA producing activity of the gel beads only 40% and that of free pellets lost completely. In order to improve the production yield, further experiments were designed. It was found that L-DOPA production could be prolonged with repeated batch wise use of immobilized mycelial pellets in calcium alginate retaining 80% of their L-DOPA producing capacity for a period of 72 h while free pellets lost completely within 24 h. Results of this kind therefore is interesting and promising for commercial scale production of L-DOPA from microbial sources.展开更多
A morphologically structured model is proposed to describe the batch fermentation of lovastatin according to the growth kinetics of filamentous microorganisms. Three kinds of hyphae are considered in the model: active...A morphologically structured model is proposed to describe the batch fermentation of lovastatin according to the growth kinetics of filamentous microorganisms. Three kinds of hyphae are considered in the model: actively growing hyphae, non-growing hyphae and deactivated hyphae. Furthermore, actively growing hyphae consist of three morphological compartments: apical compartment which gives rise to hyphal tip extension; subapical compartment which is related to hyphal branching; and hyphal compartment which is only responsible for secondary metabolite formation. The kinetics of mycelial growth mechanism is summarized and applied in modeling lovastatin fermentation. A Michaelis-Menten kinetic model with substrate inhibition is proposed for product formation. As expected, the model simulations fit well with experimental data obtained either from a laboratory scale 10L fer-menter or from a pilot-plant scale fermenter.展开更多
The title compound, neogeodin hydrate (C17H14C1208, CAS: 94540-50-8), was derived from marine fungus Aspergilhts terreus CRIM301. It was unequivocally characterized by IR, NMR spectroscopies, and single-crystal X-r...The title compound, neogeodin hydrate (C17H14C1208, CAS: 94540-50-8), was derived from marine fungus Aspergilhts terreus CRIM301. It was unequivocally characterized by IR, NMR spectroscopies, and single-crystal X-ray crystallography and tested for various biological activities. Neogeodin hydrate crystallizes in the triclinic space group P1 with a = 8.1159(5) A, b = 8.2472(4) A, c= 14.1278(7) A, a = 81.448(2)°, β = 84.860(2)°, γ= 70.400(2)°, V = 880.13(8) A3; Z = 2. It comprises a diphenyl ether, asterric acid skeleton and dichloro substituents. The methoxyphenoxy rings of the inversely related molecules form a ribbon-like structure that is stabilized by O-H...O hydrogen bonds through the doubly disordered carboxyl groups and by C-H...O interactions, generating the same R22(8) ring motif. The chlorinated methylbenzoate rings, making mostly a right angle, link the parallel upper and lower ribbons via bifurcated O-H...O and C-H...O hydrogen bonds, yielding endless channels. The channels formed are further sustained by C-H...O and π...π interactions Neogeodin hydrate exhibits inhibition against superoxide anion radical formation in the xanthine/xanthine oxidase (XXO) assay, but has no aromatase inhibitory activity.展开更多
Application of the computer image analysis for improving microbial viability assessment by plate count and fluorescence microscopy was investigated. Yeast cells were used as a model microorganism. The application of t...Application of the computer image analysis for improving microbial viability assessment by plate count and fluorescence microscopy was investigated. Yeast cells were used as a model microorganism. The application of the improved methods for the viability assessment of yeast cells after preservation by freezing and freeze-drying was demonstrated.展开更多
This study reports lovastatin production by solid state fermentation using pomegranate seeds as a substrate. Six different fungal strains and several agro-industrial wastes were selected and screened. Various physico-...This study reports lovastatin production by solid state fermentation using pomegranate seeds as a substrate. Six different fungal strains and several agro-industrial wastes were selected and screened. Various physico-chemical parameters were optimized to improve lovastatin. Moreover, chemical mutation was systematically employed to enhance lovastatin yield on selected strains. Productivity of 3 ± 0.06 mg lovastatin/gm dfm was obtained prior to optimization. One factor a time followed by Response Surface Methodology (RSM) gave 4.2 ± 0.10 mg lovastatin/gm dfm yield in an optimized setup with pomegranate seed powder (5 gms), KH2PO4 (0.1% w/v), glucose (5% w/v), moisture (60% w/w), pH 5 in a 15 days fermentation cycle. The production was further increased to 6.5 ± 0.08 mg lovastatin/gm dfm through chemical mutation of the strain. This process is simple and reproducible for the production of lovastatin using pomegranate seed as an agro-industrial waste.展开更多
目的从1株南沙群岛柳珊瑚来源真菌Aspergillus terreus(NS02-09)中分离鉴定海洋天然产物,对所得化合物进行结核分枝杆菌酪氨酸磷酸激酶(mPTPB)抑制活性评价。方法运用多种色谱手段分离纯化化合物,利用NMR、CD等现代波谱分析方法,对化合...目的从1株南沙群岛柳珊瑚来源真菌Aspergillus terreus(NS02-09)中分离鉴定海洋天然产物,对所得化合物进行结核分枝杆菌酪氨酸磷酸激酶(mPTPB)抑制活性评价。方法运用多种色谱手段分离纯化化合物,利用NMR、CD等现代波谱分析方法,对化合物进行结构鉴定,通过衍生物制备获得2个乙酰化衍生物(2a和2b);并对化合物2及其衍生物2a和2b进行mPTPB酶抑制活性测试。结果鉴定了1个土曲霉酮(1)和1个丁烯酸内酯(2)的结构;2具有较强的mPTPB酶抑制活性,而其乙酰化产物(2a和2b)的mPTPB酶抑制活性显著降低。运用Sybyl X 1.3软件,对2与mPTPB酶的模拟对接计算发现,丁烯酸内酯环及环上的羟基是化合物2发挥酶抑制活性的重要作用基团。结论从柳珊瑚来源真菌A.terreus(NS02-09)中发现了具有mPTPB酶抑制活性的丁烯酸内酯类化合物,并对其作用机制进行了计算研究,该类化合物的相关研究对抗结核药物先导化合物发现具有借鉴作用。展开更多
从蓝花黄芩内生真菌土曲霉(Aspergillusterreus)HQ100X-1发酵产物中分离得到2个新化合物[terrustone(1)和asperteretone G (2)], 10个已知化合物(3~12), terrustone (1)为具有4个连续手性中心的三羟基环戊酮类化合物,它们的结构以及绝...从蓝花黄芩内生真菌土曲霉(Aspergillusterreus)HQ100X-1发酵产物中分离得到2个新化合物[terrustone(1)和asperteretone G (2)], 10个已知化合物(3~12), terrustone (1)为具有4个连续手性中心的三羟基环戊酮类化合物,它们的结构以及绝对构型是通过1D/2D NMR结合电子圆二色谱(ECD)计算来确定.抗菌实验表明,化合物rbrolide R (4)对金黄色葡萄球菌有一定的抑菌活性,其最低抑菌浓度(MIC)值为2.5μg/mL.展开更多
The present study was designed to isolate and purify chemical constituents from solid culture of endophyte Aspergillus terreus LQ, using silica gel column chromatography, gel filtration with Sephadex LH-20, and HPLC. ...The present study was designed to isolate and purify chemical constituents from solid culture of endophyte Aspergillus terreus LQ, using silica gel column chromatography, gel filtration with Sephadex LH-20, and HPLC. Fumigaclavine I(1), a new alkaloid, was obtained, along with seven known compounds, including fumigaclavine C(2), rhizoctonic acid(3), monomethylsulochrin(4), chaetominine(5), spirotryprostatin A(6), asperfumoid(7), and lumichrome(8). The structure of compound 1 was elucidated by various spectroscopic analyses(UV, MS, 1D and 2D NMR). The in vitro cytotoxicity of compound 1 was determined by MTT assay in human hepatocarcinoma cell line SMMC-7721, showing weaker cytotoxicity, compared with cisplatin, a clinically used cancer chemotherapeutic agent.展开更多
基金Supported by Non-funded Science and Technology Research Plan of Zhanjiang City(2023B01023)School-level Education and Teaching Reform Project of Lingnan Normal University(LNJW[2022]154).
文摘[Objectives]To analyze the gene structure of the protein that predicts 6-hydroxymellein synthase of Aspergillus terreus and predict the characteristics and functions of the protein structure encoded by the gene.[Methods]Various information analysis tools in NCBI,CBS and ExPASy websites were adopted.[Results]The QODIPO gene had a full length of 2954 bp,with 952 amino acids in the coding area,and QODIPO had the highest homology with the hypothetical protein ATETN484_0003008800.The molecular weight of QOD1PO protein was 105040.56,the theoretical isoelectric point(pl)was 5.69 and the grand average of hydropathieity was-0.242.It was speculated that QODIPO was an unstable and non-secretory hydrophilic protein located in cytoplasm without transmembrane domain or signal peptide.It could be predicted that the secondary structure of QODIPO encoding protein consisted mainly of random coil,α-helix and a PKS-DH anhydrase domain.[Conclusions]The results will lay a theoretical foundation for cloning and expression of 6-hydroxymellein synthase and further understanding of its activity and function.
基金supported by the Guangdong Basic and Applied Basic Research Foundation,China(No.2023A1515012146)the National Natural Science Foundation of China(No.52271083)+1 种基金the Fundamental Research Funds for the Central Universities,China(No.22qntd0801)the Shanghai Engineering Technology Research Centre of Deep Offshore Material,China(No.19DZ2253100)。
文摘The effect of ultraviolet(UV)radiation and biocide benzalkonium chloride(BKC)on fungal-induced corrosion of AA7075 induced by Aspergillus terreus(A.terreus)was deeply studied using analysis of biological activity,surface analysis,and electrochemical measurements.Results demonstrated that the planktonic and sessile spore concentrations decline by more than two orders of magnitude when UV radiation and BKC are combinedly used compared with the control.UV radiation can inhibit the biological activity of A.terreus and influence the stability of passive film of AA7075.Except for direct disinfection,the physical adsorption of BKC on the specimen can effectively inhibit the attachment of A.terreus.The combination of UV radiation and BKC can much more effectively inhibit the corrosion of AA,especially pitting corrosion,due to their synergistic effect.The combined application of UV radiation and BKC can be a good method to effectively inhibit fungal-induced corrosion.
基金Project (No. 20061475) supported by Education Department of Zhejiang Province, China
文摘Lovastatin production by Aspergillus terreus ATCC 20542 in solid-state fermentation (SSF) was studied. Various substrates were used to evaluate the ability ofA. terreus to produce lovastatin. The results showed that either rice or wheat bran was suitable substrate for lovastatin production in SSF. The maximum yield of lovastatin (2.9 mg/g dry substrate) using rice as substrate was achieved after incubating for 11 d at the following optimized process parameters: 50%-60% initial moisture content, pH 5.5, incubation temperature 28 ℃.
文摘Cassava (Manihot esculenta, Crantz) is one of the most important food plants in West Africa. Its peels are made up of cellulose, hemicellulose and lignin. This lignocellulolytic biomass can be converted using microbial enzymes to fermentable sugars which have wide range of biotechnological relevance in many fermentation processes. The aim of this study is to screen filamentous fungi from decaying cassava peels that are good producers of xylanases and cellulases. Decaying parts of cassava peels were obtained and brought to the laboratory for further work. Fungi were isolated, identified and screened for cellulase and xylanase production. Isolate with highest frequency of occurrence and enzyme production was identified using phenotypic and molecular method. Optimisation of growth conditions for enzymes production was monitored using the DNSA method, also saccharification of cassava peel were carried out using the enzymes obtained from the isolate. Aspergillus terreus KJ829487 was the predominant fungus. It produces cellulases and xylanases optimally at 40°C, pH 6 and 8, utilising carboxymethylcellulose (CMC) or xylose and yeast extracts as its carbon and nitrogen sources respectively. Saccharification of the peels yielded 584 mg/L glucose, 78 mg/L xylose and 66 mg/L rhamnose. Aspergillus terreus KJ829487 obtained from cassava peels have the ability to produce high concentration cellulases and xylanases which effectively hydrolysed the lignocelluloses’ biomass to fermentable sugars.
基金CBL received a master fellowship from Coordenacao de Aperfeicoamento de Pessoal de Nível Superior(CAPES).
文摘L-asparaginase is a chemotherapeutic drug used in the treatment of lymphoblastic leukemia. In the present study, the extracellular L-asparaginase produced by strain (PC-1.7A) of Aspergillus terreus was purified, characterized, and modified with polyethylene glycol. Moreover, its antiproliferative activity was evaluated. The apparent molecular weight of the enzyme was found to be 136 kDa. The optimal pH and temperature for the enzyme were 9.0℃ and 40℃, respectively. The enzyme retained 100% of the activity at 40℃ for 120 min. Pegylated L-asparaginase was more thermostable and more resistant to trypsin than native enzyme. Native L-asparaginase against human normal cells did not show cytotoxicity. However, in the leukemia cell lines RS4;11 and HL60 the antiproliferative effects of native L-asparaginase were observed after 96 and 72 h of incubation, respectively. For the first time, an L-asparaginase from fungus was evaluated as an antitumor agent in human cells lines and further investigations should be conducted to improve the knowledge about this enzyme.
文摘Itaconic acid is commercially produced by the cultivation of Aspergillus terreus using starch hydrolysate as carbon source. The degree of hydrolysis had a great influence on itaconic acid production which was suitable when corn starch was saccharified at 35 DE. The α-amylase was sufficient to drive the starch hydrolysis to the degree. The agar plate assay with LiCl treatment provided a rapid, simple and unequivocal method for screening large numbers of colonies for itaconic acid producing strains. It was learned by experience that the strains on the plates with thick hyphae and light-colored spores often accompanied high itaconic acid production. A strain, designated Ast165, producing itaconic acid with a high yield, was successfully obtained by directional breeding of metabolic end products resistant strains. The itaconic acid concentration produced by Ast165 was 53.8 g/l from 100 g/l of starch hydrolysate in shake flasks. The conversion rate was 61.3%, which was the highest value found in tests.
文摘RAPD was used to examine the genetic variability among five isolates of Aspergillus terreus spp.. Two random primers were selected for the RAPD assay PG01–5’ CAGGTGTTGC 3’ and PG02–5’ CTGGACAGAC 3’ (Progen Technologies). The characterization of Aspergillus terreus species have been mostly applied on the basis of morphology, phenotype and physiology. DNA Polymorphisms are based on differences in DNA sequences and have advantages over protein polymorphisms. But morphological characterization besides molecular tools will remain a basic and powerful key in the identification of Aspergillus terreus species. The objective of the present study was to isolate the fungal contaminants from dried grapes and compare the genomic profile of the Aspergillus terreus speices isolated from the dried grapes, through RAPD analysis. In the present study with primer PG 01 four different discriminations was there among the A. terreus isolates. There was a homology of genotype between the isolates 1 & 3. And with primer PG 02 four different discriminations were there and there was a homology between 1 & 3. The predominant type was type I in primer I & II. The other isolates belonged to 2, 3 and 4. No similarity was detected for isolates 3, 4 and 5 indicating great genomic diversity of A. terreus.
文摘The objective of this study is to improve the production of L-DOPA from fungal source like Aspergillus terreus that can be further used to large-scale commercial production of this important drug from microbial sources. L-DOPA, a dopamine precursor that can pass the blood-brain barrier, is presently the drug of choice for Parkinson's disease. Microbial production and isolation of L-DOPA from natural sources is yet to be achieved an economical process. In this study, the mycelial pellets ofAspergillus terreus 104 were entrapped in 2% calcium alginate and were studied for their capacity for L-3, 4-dihydroxyphenylalanine production. Results showed that the immobilized pellets produced L-DOPA to the extent of 0.74 mg·G^-1 biomass while the free pellets produced 0.8 mg·G^-1 biomass. Further, storage of immobilized pellets for 96 h at 4 ℃ resulted in the reduction of the original L-DOPA producing activity of the gel beads only 40% and that of free pellets lost completely. In order to improve the production yield, further experiments were designed. It was found that L-DOPA production could be prolonged with repeated batch wise use of immobilized mycelial pellets in calcium alginate retaining 80% of their L-DOPA producing capacity for a period of 72 h while free pellets lost completely within 24 h. Results of this kind therefore is interesting and promising for commercial scale production of L-DOPA from microbial sources.
文摘A morphologically structured model is proposed to describe the batch fermentation of lovastatin according to the growth kinetics of filamentous microorganisms. Three kinds of hyphae are considered in the model: actively growing hyphae, non-growing hyphae and deactivated hyphae. Furthermore, actively growing hyphae consist of three morphological compartments: apical compartment which gives rise to hyphal tip extension; subapical compartment which is related to hyphal branching; and hyphal compartment which is only responsible for secondary metabolite formation. The kinetics of mycelial growth mechanism is summarized and applied in modeling lovastatin fermentation. A Michaelis-Menten kinetic model with substrate inhibition is proposed for product formation. As expected, the model simulations fit well with experimental data obtained either from a laboratory scale 10L fer-menter or from a pilot-plant scale fermenter.
基金supported by the grant of Rangsit University to SJthe Chulalongkorn University Centenary Academic Development Project(CU56-FW10)+2 种基金National Research University Project(FW657B)to TAthe Thailand Research Fund(No.DBG5180014)the Center for Environmental Health,Toxicology and Management of Chemicals to PK
文摘The title compound, neogeodin hydrate (C17H14C1208, CAS: 94540-50-8), was derived from marine fungus Aspergilhts terreus CRIM301. It was unequivocally characterized by IR, NMR spectroscopies, and single-crystal X-ray crystallography and tested for various biological activities. Neogeodin hydrate crystallizes in the triclinic space group P1 with a = 8.1159(5) A, b = 8.2472(4) A, c= 14.1278(7) A, a = 81.448(2)°, β = 84.860(2)°, γ= 70.400(2)°, V = 880.13(8) A3; Z = 2. It comprises a diphenyl ether, asterric acid skeleton and dichloro substituents. The methoxyphenoxy rings of the inversely related molecules form a ribbon-like structure that is stabilized by O-H...O hydrogen bonds through the doubly disordered carboxyl groups and by C-H...O interactions, generating the same R22(8) ring motif. The chlorinated methylbenzoate rings, making mostly a right angle, link the parallel upper and lower ribbons via bifurcated O-H...O and C-H...O hydrogen bonds, yielding endless channels. The channels formed are further sustained by C-H...O and π...π interactions Neogeodin hydrate exhibits inhibition against superoxide anion radical formation in the xanthine/xanthine oxidase (XXO) assay, but has no aromatase inhibitory activity.
文摘Application of the computer image analysis for improving microbial viability assessment by plate count and fluorescence microscopy was investigated. Yeast cells were used as a model microorganism. The application of the improved methods for the viability assessment of yeast cells after preservation by freezing and freeze-drying was demonstrated.
文摘This study reports lovastatin production by solid state fermentation using pomegranate seeds as a substrate. Six different fungal strains and several agro-industrial wastes were selected and screened. Various physico-chemical parameters were optimized to improve lovastatin. Moreover, chemical mutation was systematically employed to enhance lovastatin yield on selected strains. Productivity of 3 ± 0.06 mg lovastatin/gm dfm was obtained prior to optimization. One factor a time followed by Response Surface Methodology (RSM) gave 4.2 ± 0.10 mg lovastatin/gm dfm yield in an optimized setup with pomegranate seed powder (5 gms), KH2PO4 (0.1% w/v), glucose (5% w/v), moisture (60% w/w), pH 5 in a 15 days fermentation cycle. The production was further increased to 6.5 ± 0.08 mg lovastatin/gm dfm through chemical mutation of the strain. This process is simple and reproducible for the production of lovastatin using pomegranate seed as an agro-industrial waste.
文摘目的从1株南沙群岛柳珊瑚来源真菌Aspergillus terreus(NS02-09)中分离鉴定海洋天然产物,对所得化合物进行结核分枝杆菌酪氨酸磷酸激酶(mPTPB)抑制活性评价。方法运用多种色谱手段分离纯化化合物,利用NMR、CD等现代波谱分析方法,对化合物进行结构鉴定,通过衍生物制备获得2个乙酰化衍生物(2a和2b);并对化合物2及其衍生物2a和2b进行mPTPB酶抑制活性测试。结果鉴定了1个土曲霉酮(1)和1个丁烯酸内酯(2)的结构;2具有较强的mPTPB酶抑制活性,而其乙酰化产物(2a和2b)的mPTPB酶抑制活性显著降低。运用Sybyl X 1.3软件,对2与mPTPB酶的模拟对接计算发现,丁烯酸内酯环及环上的羟基是化合物2发挥酶抑制活性的重要作用基团。结论从柳珊瑚来源真菌A.terreus(NS02-09)中发现了具有mPTPB酶抑制活性的丁烯酸内酯类化合物,并对其作用机制进行了计算研究,该类化合物的相关研究对抗结核药物先导化合物发现具有借鉴作用。
文摘从蓝花黄芩内生真菌土曲霉(Aspergillusterreus)HQ100X-1发酵产物中分离得到2个新化合物[terrustone(1)和asperteretone G (2)], 10个已知化合物(3~12), terrustone (1)为具有4个连续手性中心的三羟基环戊酮类化合物,它们的结构以及绝对构型是通过1D/2D NMR结合电子圆二色谱(ECD)计算来确定.抗菌实验表明,化合物rbrolide R (4)对金黄色葡萄球菌有一定的抑菌活性,其最低抑菌浓度(MIC)值为2.5μg/mL.
基金financially supported by National Natural Science Foundation of China(Nos.21372191 and 31370079)Jiangsu Province Natural Science Foundation(No.BK20130437)
文摘The present study was designed to isolate and purify chemical constituents from solid culture of endophyte Aspergillus terreus LQ, using silica gel column chromatography, gel filtration with Sephadex LH-20, and HPLC. Fumigaclavine I(1), a new alkaloid, was obtained, along with seven known compounds, including fumigaclavine C(2), rhizoctonic acid(3), monomethylsulochrin(4), chaetominine(5), spirotryprostatin A(6), asperfumoid(7), and lumichrome(8). The structure of compound 1 was elucidated by various spectroscopic analyses(UV, MS, 1D and 2D NMR). The in vitro cytotoxicity of compound 1 was determined by MTT assay in human hepatocarcinoma cell line SMMC-7721, showing weaker cytotoxicity, compared with cisplatin, a clinically used cancer chemotherapeutic agent.