西沙马尾藻共附生真菌Aspergillus sp.SYPUF41304次级代谢产物的分离与鉴定

目的对西沙马尾藻共附生真菌Aspergillus sp.SYPUF41304的次级代谢产物进行分离与鉴定。方法利用硅胶柱色谱、凝胶柱色谱、中压反相柱色谱及半制备高效液相色谱等分离手段对马尾藻共附生真菌Aspergillus sp.SYPUF41304的液体发酵提取物进行分离纯化,并利用核磁共振、质谱等波谱学方法,结合文献对照,确定化合物结构。结果最终从提取物中分离得到10个化合物,经鉴定为吲哚-3-甲醛(1H-indole-3-carboxaldehyde)(1)、吲哚-3-乙酸甲酯(methyl indole-3-acetate)(2)、环(L-脯氨酸-L-缬氨酸)(cyclo-L-prolyl-L-valine)(3)、brevianamide F(4)、asperterreusine A(5)、talaisocoumarin A(6)、3-甲基-6-羟基-8甲氧基-3,4-二氢异香豆素(3-methyl-6-hydroxy-8-methoxy-3,4-dihydroisocoumarin)(7)、3-甲氧基-6,8-二羟基-3-甲基-3,4-二氢异香豆素(3-methoxy-6,8-dihydroxy-3-methyl-3,4-dihydroisocoumarin)(8)、4-hydroxykigelin(9)和de-O-methyldiaporthin(10)。结论化合物按结构类型可分为生物碱和聚酮类等,化合物4~8均为首次从该属真菌中分离得到。所有化合物在4 mg·mL^(-1)浓度下,均未显示出抗细菌活性。

华泽兰内生真菌Aspergillus puniceus次级代谢产物及其抗三阴性乳腺癌活性和作用机制

从华泽兰根部分离得到一株内生真菌Aspergillus puniceus.采用正相硅胶柱色谱、Sephadex LH-20凝胶柱色谱及半制备高效液相色谱等方法,从该菌株的发酵液中分离得到8个结构类似的口山酮类化合物,通过现代波谱技术分别鉴定为3′,4′-hydrogenated austocystins A(1)、austocystin M(2)、austocystin F(3)、austocystin D(4)、austocystin B(5)、austocystin K(6)、austocystin A(7)、austocystin H(8).MTT结果显示化合物5对三阴性乳腺癌MDA-MB-231细胞具有较好的选择性细胞毒活性(IC_(50)为1.28μmol·L^(-1)).另外,流式细胞术检测化合物5作用于MDA-MB-231细胞后凋亡率的变化,相比于对照组,最高总凋亡率为69.7%.同时,AO/EB双荧光染色也证明化合物5能够诱导MDA-MB-231的细胞凋亡.JC-1线粒体膜电位检测进一步显示化合物5能够通过线粒体途径诱导三阴性乳腺癌MDA-MB-231的细胞凋亡.

Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet

BACKGROUND The gluten-free diet(GFD)has limitations,and there is intense research in the development of adjuvant therapies.AIM To examine the effects of orally administered Aspergillus niger prolyl endopeptidase protease(AN-PEP)on inadvertent gluten exposure and symptom prevention in adult celiac disease(CeD)patients following their usual GFD.METHODS This was an exploratory,double-blind,randomized,placebo-controlled trial that enrolled CeD patients on a long-term GFD.After a 4-wk run-in period,patients were randomized to 4 wk of two AN-PEP capsules(GliadinX;AVI Research,LLC,United States)at each of three meals per day or placebo.Outcome endpoints were:(1)Average weekly stool gluten immunogenic peptides(GIP)between the run-in and end of treatments and between AN-PEP and placebo;(2)celiac symptom index(CSI);(3)CeD-specific serology;and(4)quality of life.Stool samples were collected for GIP testing by ELISA every Tuesday and Friday during run-ins and treatments.RESULTS Forty patients were randomized for the intention-to-treat analysis,and three were excluded from the per-protocol assessment.Overall,628/640(98.1%)stool samples were collected.GIP was undetectable(<0.08μg/g)in 65.6%of samples,and no differences between treatment arms were detected.Only 0.5%of samples had GIP concentrations sufficiently high(>0.32μg/g)to potentially cause mucosal damage.Median GIP concentration in the AN-PEP arm was 44.7%lower than in the run-in period.One-third of patients exhibiting GIP>0.08μg/g during run-in had lower or undetectable GIP after AN-PEP treatment.Compared with the run-in period,the proportion of symptomatic patients(CSI>38)in the AN-PEP arm was significantly lower(P<0.03).AN-PEP did not result in changes in specific serologies.CONCLUSION This exploratory study conducted in a real-life setting revealed high adherence to the GFD.The AN-PEP treatment did not significantly reduce the overall GIP stool concentration.However,given the observation of a significantly lower prevalence of patients with severe symptoms in the AN-PEP arm,further clinical research is warranted.

Polysaccharides of Aspergillus cristatus attenuate obesity by regulating gut microbiota and gut microbiota-related metabolites

Golden-flower fungus,the only dominant microorganism determining the Fu-brick tea quality through fermentation and the important microbe in Liupao tea,is considered a potential probiotic fungus based on its anti-obesity effect.However,the classification of golden-flower fungi is still controversial;the anti-obesity effect of golden-flower fungus polysaccharides remains unknown.In this study,we identify a golden-flower strain as Aspergillus cristatus based on morphological characteristics and multigene phylogeny analysis,which resolves the controversy of classification.Moreover,we find A.cristatus polysaccharides(ACPS)attenuate obesity in rats.ACPS modulate gut bacterial composition.in which Akkermansia,Akkermansia muciniphila,Bacteroides,Romboutsia,Blautia,and Desulfovibrio are considered the core microbes regulated by ACPS.ACPS increase fecal total short-chain fatty acid content and serum,hepatic,and fecal total bile acid content.Furthermore,ACPS-induced gut microbiota alteration plays a causal role in the protection from obesity,according to a fecal transplantation experiment.Thus,ACPS ameliorate obesity by regulating gut microbiota and gut microbiota-related metabolites.

Aspergillus niger prolyl endopeptidase in celiac disease

We comment here on the article by Stefanolo et al entitled“Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet”,published in the World Journal of Gastroenterology.Celiac disease is a well-recognized systemic autoimmune disorder.In genetically susceptible people,the most evident damage is located in the small intestine,and is caused and worsened by the ingestion of gluten.For that reason,celiac patients adopt a gluten-free diet(GFD),but it has some limitations,and it does not prevent re-exposure to gluten.Research aims to develop adjuvant therapies,and one of the most studied alternatives is supplementation with Aspergillus niger prolyl endopeptidase protease(AN-PEP),which is able to degrade gluten in the stomach,reducing its concentration in the small intestine.The study found a high adherence to the GFD,but did not address AN-PEP as a gluten immunogenic peptide reducer,as it was only tested in patients following a GFD and not in gluten-exposing conditions.This study opens up new research perspectives in this area and shows that further study is needed to clarify the points that are still in doubt.

Enzymatic Characterization of Pectinex XXL,a Pectinase Produced by Aspergillus niger,and Its Application in Fruit Juice Production

Pectinex XXL,a commercially prepared pectinase,was investigated for its potential application in the fruit juice industry.Polygalacturonic acid was used as the substrate for determining the enzymatic properties of Pectinex XXL using the DNS method.According to the results,the optimal pH for Pectinex XXL activity was 4.5,and the enzyme was stable in the pH range of 3.0~4.5.The optimal pH and pH stability range are consistent with those of some tropical and subtropical fruits.The optimal temperature for Pectinex XXL activity was 60℃,and the enzyme remained stable after one hour in a water bath set at 40℃.Additionally,the enzymatic activity was not inhibited in the presence of 1 mmol/L of Na^(+),Mg^(2+),Ba^(2+),Co^(2+),Zn^(2+),and Fe^(2+),whereas it was slightly inhibited in the presence of 2 mmol/L of K^(+)and Fe^(2+)and partially inhibited in the presence of 1 and 2 mmol/L of Ca^(2+)and Mn^(2+),demonstrating its good stability in acids and excellent thermal catalytic performance.Based on the above experimental results,depectinization experiments were performed on plantain and cherry tomato juices using different amounts of Pectinex XXL.After one hour reaction with 16 U/mL of the enzyme,the yields of the plantain and cherry tomato juices were substantially increased by 119.03%and 15.97%,respectively,while their light transmittance was remarkably enhanced by 37.65%and 12.35%,respectively.Furthermore,the enzyme reduced the viscosity of the plantain and cherry tomato juices by 88.29%and 29.50%,respectively.The juice production experiments confirmed that this enzyme can significantly improve the yield and light transmittance of plantain juice,while effectively reducing its viscosity.These findings indicate the potential of Pectinex XXL in the industrial production of plantain juice.

Identifying genetic susceptibility to Aspergillus fumigatus infection using collaborative cross mice and RNA-Seq approach

Background:Aspergillus fumigatus(Af)is one of the most ubiquitous fungi and its infection potency is suggested to be strongly controlled by the host genetic back-ground.The aim of this study was to search for candidate genes associated with host susceptibility to Aspergillus fumigatus(Af)using an RNAseq approach in CC lines and hepatic gene expression.Methods:We studied 31 male mice from 25 CC lines at 8 weeks old;the mice were infected with Af.Liver tissues were extracted from these mice 5 days post-infection,and next-generation RNA-sequencing(RNAseq)was performed.The GENE-E analysis platform was used to generate a clustered heat map matrix.Results:Significant variation in body weight changes between CC lines was ob-served.Hepatic gene expression revealed 12 top prioritized candidate genes differ-entially expressed in resistant versus susceptible mice based on body weight changes.Interestingly,three candidate genes are located within genomic intervals of the previ-ously mapped quantitative trait loci(QTL),including Gm16270 and Stox1 on chromo-some 10 and Gm11033 on chromosome 8.Conclusions:Our findings emphasize the CC mouse model's power in fine mapping the genetic components underlying susceptibility towards Af.As a next step,eQTL analysis will be performed for our RNA-Seq data.Suggested candidate genes from our study will be further assessed with a human cohort with aspergillosis.

CD3ε of a pan T cell marker involved in mouse Aspergillus fumigatus keratitis

AIM:To explore whether CD3ε is involved in the adaptive immunity of Aspergillus fumigatus(A.fumigatus)keratitis in mice and the role of innate and adaptive immunity in it.METHODS:Mice models of A.fumigatus keratitis were established by intra-stromal injection and corneal epithelial scratching.Subconjunctival injections of natamycin,wedelolactone,LOX-1 inhibitor(poly I)or Dectin-1 inhibitor(laminarin)were used to treat mice with A.fumigatus keratitis.Mice were pretreated by intraperitoneal injection of anti-mouse CD3ε.We observed the corneal infection of mice under the slit lamp microscope and made a clinical score.The protein expression of CD3ε and interleukin-10(IL-10)was determined by Western blotting.RESULTS:With the disease progresses,the degree of corneal opacity and edema augmented.In the intrastromal injection models,CD3εprotein expression began to increase significantly on the 2^(nd) day.However,in the scraping epithelial method models,CD3ε only began to increase on the 3^(rd) day.After natamycin treatment,the degree of corneal inflammation in mice was significantly attenuated on the 3^(rd) day.After wedelolactone treatment,the severity of keratitis worsened.And the amount of CD3ε protein was also reduced,compared with the control group.By inhibiting LOX-1 and Dectin-1,there was no significant difference in CD3ε production compared with the control group.After inhibiting CD3ε,corneal ulcer area and clinical score increased,and IL-10 expression was downregulated.CONCLUSION:As a pan T cell marker,CD3ε participate in the adaptive immunity of A.fumigatus keratitis in mice.In our mice models,the corneas will enter the adaptive immune stage faster.By regulating IL-10,CD3ε exerts antiinflammatory and repairs effects in the adaptive immune stage.

北部湾海洋真菌Aspergillus fumigatus DL-p0m-g2的化学成分及药理活性研究

为获得具有生物活性的化合物,对一株分离于北部湾钉螺菌株Aspergillus fumigatus DL-p0m-g2的化学成分及药理活性进行研究。综合应用反相ODS(octadecylsilyl)柱色谱、半制备液相等多种色谱学方法进行分离纯化,根据化合物理化性质、质谱和核磁共振波谱学数据进行结构鉴定,并对分离得到的化合物进行细胞毒活性、抑菌活性和胆固醇转运蛋白NPC1L1(NPC1-like intracellular cholesterol transporter 1)蛋白结合等生物活性评价。实验共分离得到21个生物碱类化合物和1个甾体,分别鉴定为6-methoxyspirotryprostatin B(1)、spirotryprostatin A(2)、fumitremorgin C(3)、cyclotryprostatin A(4)、fumitremorgin B(5)、pseurotin A(6)、azaspirofuran A(7)、azaspirofuran B(8)、cephalimysin C(9)、cephalimysin B(10)、fumiquinazoline C(11)、fumiquinazoline B(12)、fumiquinazoline A(13)、fumiquinazoline D(14)、fumiquinazoline F(15)、tryprostatin B(16)、verruculogen(17)、chaetominine(18)、bisdethiobis(methylthio)glitoxin(19)、helvolic acid(20)、7-deacetylpyripyropene A(21)、terezine D(22)。其中化合物6对人肝癌细胞(Hep G2)、人肺癌细胞(A549)、人直肠癌细胞(HCT116)有一定的细胞毒活性;化合物1、3和20对金黄色葡萄球菌表现出抑菌活性;化合物14与NPC1L1蛋白具有较好的结合,显示其在降脂药物开发中的研究潜力。

水母共附生真菌Aspergillus fumigatus SCSIO41214中生物碱类化合物研究

从水母共附生真菌Aspergillus fumigatus SCSIO41214中分离得到8个已知生物碱类化合物。这些化合物主要采用包括正相硅胶、反相硅胶等常规柱层析技术,以及高效液相色谱进行分离纯化。首次通过核磁共振波谱等多种现代波谱技术确定了化合物1的平面结构,通过单晶衍射技术确定了其相对构型,化合物2-8是通过波谱分析并结合文献数据比对确定了化合物的结构。体外抗炎活性研究筛选发现,化合物4在10μmol·L^(-1)浓度下显示弱的抑制RAW264.7细胞中LPS引起的NO的释放。

海洋真菌Aspergillus candidus HM5-4次生代谢产物的研究

目的 对海绵共附生真菌Aspergillus candidus HM5-4的次生代谢产物及其生物活性进行研究。方法 综合运用硅胶柱色谱、凝胶柱色谱以及半制备型高效液相色谱等分离技术对该菌株的大米发酵产物进行分离纯化;通过波谱数据和理化常数分析,并结合文献数据比对,鉴定化合物的结构;分别采用滤纸片法和MTT法对所分离鉴定的化合物进行抗菌和细胞毒活性测试。结果 从A. candidus HM5-4的发酵产物中共分离鉴定10个化合物,其结构分别为:氯黄菌素(1)、4"-deoxyterphenyllin(2)、蓟黄素(3)、asperterphenyllin(4)、prenylcandidusin(5)、2,4-二甲氧基-1,10-二羟基对联三苯(6)、(±)-2-羟基-3-苯基丁酸(7)、candidusin A(8)、candidusin B(9)和aspergivone(10),其中化合物7为新的天然产物。生物活性测试结果显示,化合物1对火龙果溃疡病原菌有很强的抑制作用,当供试浓度为10.0μg/disc时,其抑菌圈直径为(41.67±2.36) mm;化合物8对白血病细胞K562、肝癌细胞BEL-7402、胃癌细胞SGC-7901、肺癌细胞A549和宫颈癌细胞Hela有一定的细胞毒活性,其IC_(50)分别为(17.51±0.11)、(31.45±0.11)、(32.27±0.20)、(77.43±0.26)和(68.88±0.57)μmol/L,化合物2对白血病细胞K562具有细胞毒活性,其IC_(50)为(94.58±1.21)μmol/L。结论 海绵共附生真菌A. candidus HM5-4具有生产抗菌、细胞毒活性先导化合物的潜在研究价值。

海洋真菌Aspergillus jensenii SS5中化学成分研究

利用多种柱色谱分离技术从海洋真菌Aspergillus jensenii SS5的液体发酵产物中分离获得4个已知化合物,并通过NMR、HR-ESI-MS、X单晶衍射等技术鉴定了它们的结构,分别是epigriseofulvin(1)、sterigmatocystin(2)、brevianamide M(3)、meleagrin(4),其中化合物1~3是首次从曲霉属真菌A.jensenii中分离获得。采用SRB法对分离获得的天然产物进行体外细胞毒性测试,结果表明化合物4对人肺癌A549细胞和人肝癌Bel-7402细胞均有较好抑制作用,化合物2对A549人肺癌细胞株有较好抑制作用。本研究作为海洋真菌A.jensenii SS5的化学成分的补充研究,发现了2个具有较好细胞毒活性的化合物,为曲霉属海洋真菌活性天然产物的开发提供了理论依据。

海绵共附生真菌Aspergillus giganteus MA 46-5吲哚喹唑啉类生物碱成分

对1株富产吲哚喹唑啉类生物碱(IQAs)的海绵共附生真菌Aspergillus giganteus MA 46-5的IQAs类成分进行了研究。根据IQAs的结构特征,在TLC、LC-MS和GNPS(global natural products social molecular networking)技术的共同指导下,从大米培养基的乙酸乙酯部位分离得到10个IQAs类生物碱。通过NMR、HR-ESI-MS、OR和CD等方法并结合文献比对鉴定其分别为:tryptoquivaline(1)、nortryptoquivaline(2)、deoxytryptoquivaline(3)、deoxynortryptoquivaline(4)、aspertoryadin C(5)、aspertoryadin G(6)、quinadoline A(7)、fiscalin E (8)、quinadoline B(9)和prelapatin B(10)。8和10为首次从Aspergillus属中得到,2、4~7为首次从Aspergillus giganteus中分离得到。

Evaluation of in vitro digestibility of Aspergillus oryzae fungal biomass grown on organic residue derived‑VFAs as a promising ruminant feed supplement

Background As demand for high quality animal feed continues to raise,it becomes increasingly important to mini-mize the environmental impact of feed production.An appealing sustainable approach to provide feed fractions is to use organic residues from agro-food industry.In this regard,volatile fatty acids(VFAs)such as acetic,propionic and butyric acids,derived from bioconversion of organic residues can be used as precursors for production of micro-bial protein with ruminant feed inclusion potential.This study aims to investigate the in vitro digestibility of the Asper-gillus oryzae edible fungal biomass cultivated on VFAs-derived from anaerobic digestion of residues.The produced fungal protein biomass,along with hay clover silage and rapeseed meal were subjected to various in vitro assays using two-stage Tilley and Terry(TT),gas,and bag methods to evaluate and compare its digestibility for application in ruminant feed.Results The produced fungal biomass contained a higher crude protein(CP)(41%–49%)and rather similar neutral detergent fiber(NDF)(41%–56%)compared to rapeseed meal.The rumen in vitro dry matter digestibility(IVDMD)of the fungal biomass in the TT method ranged from 82%to 88%(statistically similar to that of the gas method(72%to 85%)).The IVDMD of fungal biomass were up to 26%and 40%greater than that of hay clover silage and rapeseed meal,respectively.The type of substrate and bag method had pronounced effect on the fermentation products(ammonium-N(NH4+-N),total gas and VFAs).Fungal biomass digestion resulted in the highest release of NH4+-N(340–540 mg/L)and the ratio of acetate to propionate ratio(3.5)among subjected substrates.Conclusion The results indicate that gas method can be used as a reliable predictor for IVDMD as well as fermenta-tion products.Furthermore,the high IVDMD and fermentation product observed for Aspergillus oryzae fungal biomass digestion,suggest that the supplementation of fungal biomass will contribute to improving the rumen digestion by providing necessary nitrogen and energy to the ruminant and microbiota.

A Pair of New Spirocyclic Alkaloid Enantiomers with TrxR Inhibitory Activities Were Isolated from Marine-Derived Aspergillus ruber TX-M4-1

One new spirocyclic alkaloid,5-isopentenyl-cryptoechinuline D(1),along with 11 known compounds(2–12),were iso-lated from a marine fungus Aspergillus ruber TX-M4-1.The structures of compounds 1–12 were elucidated by spectroscopic evi-dences.Compound 1 was initially isolated as an enantiomer,and further separation of 1 by chiral HPLC afforded a pair of enantio-mers,including(-)-5-isopentenyl-cryptoechinuline D(1a)and(+)-5-isopentenyl-cryptoechinuline D(1b).Their absolute configura-tions were elucidated by ECD spectroscopic data.Compounds 1a,5 and 10 could inhibit thioredoxin reductase(TrxR)activity with IC50 values of 6.2,36.3 and 18.6μmol L^(-1),respectively.Surface plasmon resonance(SPR)study also demonsrated the interactions between compounds 6,8 and Niemann-Pick C1 Like 1(NPC1L1)respectively,which indicate that compounds 6 and 8 are potential NPC1L1 inhibitors.

海洋本草软珊瑚共附生真菌Aspergillus sp.EGF7-0-1中酚酸类化学成分研究(Ⅱ)

为寻找海洋来源结构新颖的次生代谢产物,采用大米培养基对海洋本草软珊瑚(Sinularia sp.)共附生真菌Aspergillus sp.EGF7-0-1进行规模发酵,利用高效液相色谱等多种柱色谱技术对其乙酸乙酯提取物进行分离纯化;采用核磁共振波谱、高分辨质谱、旋光光谱等现代光谱学方法,并结合文献数据比对等对其进行结构鉴定,获得10个简单芳香酚酸化合物,分别为4-hydroxy-3-(3'-methyl-2'-butenyl)phenylacetic acid(1)、asperulosin C(2)、对羟基苯乙酸(3)、对羟基苯乙酸甲酯(4)、4-hydroxy-3-prenyl-benzoic acid(5)、4-hydroxy-3-(3-methylbut-2-enyl)benzaldehyde(6)、对羟基苯甲醛(7)、对羟基苯甲酸甲酯(8)、间羟基苯乙酸(9)和2,2'-oxybis(1,4)-ditert-butylbenzene(10),其中化合物1是新发现的天然产物。抗肿瘤活性研究表明,化合物1~10对人结肠癌细胞、人乳腺癌细胞、人肝癌细胞、小鼠肝癌细胞、小鼠乳腺癌细胞、小鼠黑色素瘤细胞和小鼠皮肤黑色素瘤细胞等肿瘤细胞均无活性。

Aspergillus sp.DLCS-F18胞外嗜热嗜酸β-葡萄糖苷酶的酶学性质研究

β-葡萄糖苷酶作为纤维素彻底降解为葡萄糖的关键酶,被广泛运用于饲料、食品和生物燃料等行业。然而,许多菌株分泌的胞外β-葡萄糖苷酶活性低且热稳定性差,限制了其在纤维素生物质降解中的应用。本研究使用稻草秸秆作为碳源诱导菌株Aspergillus sp.DLCS-F18分泌胞外β-葡萄糖苷酶。结果表明:其最适反应pH和温度分别为4.0和60℃,在55℃和60℃下,孵育120 min后仍能保持95%以上的相对活性。此外,其表现出对金属离子的耐受性,在10 mmol/L的Ni^(2+)、Co^(2+)、Pb^(2+)和Cu^(2+)存在时,仍保持75%以上的相对活性,发酵96 h达到最高活性(2.5±0.1)U/mL。以上结果表明Aspergillus sp.DLCS-F18胞外β-葡萄糖苷酶为嗜热嗜酸β-葡萄糖苷酶,有较强的热稳定性,且产酶周期短。这预示着其在食品、饲料和纤维素乙醇生产方面有重要的潜在运用价值。

涠洲岛海洋沉积物来源真菌Aspergillus sp.GXIMD02003的代谢产物研究

为了探讨海洋沉积物来源真菌Aspergillus sp.GXIMD02003次级代谢产物的多样性,运用多种色谱技术分离该菌株代谢产物,基于质谱、核磁共振波谱和旋光等数据结合文献数据比对鉴定化合物结构。8个化合物从真菌Aspergillus sp.GXIMD02003中分离并被鉴定为(3S,11aS)-3-[(1H-indol-3-yl)methyl]-7,9-dihydroxy-8-methoxy-2,3,11,11a-tetrahydro-6H-pyrazino[1,2-b]isoquinoline-1,4-dione(1)、cyclo(L-Pro-L-Tyr)(2)、cyclo(L-4-Hyp-D-phe)(3)、cyclo(L-4-Hyp-L-Phe)(4)、cyclo(L-4-Hyp-L-leucine)(5)、cyclo(L-4-Hyp-D-leucine)(6)、desmethyldiaportinol(7)、2-(2ʹ-hydroxypropyl)-5-methyl-7-hydroxychromone(8)。化合物1~8在测试浓度下未显示抑制癌细胞增殖、α-葡萄糖酶和抑菌活性。化合物1~8首次从涠洲岛海洋沉积物来源真菌中分离得到。

纳米银胁迫下黄曲霉(Aspergillus flavus)TL-F3的氧化应激响应及其吸附能力

为研究纳米银(AgNPs)胁迫下黄曲霉(Aspergillus flavus TL-F3)的氧化应激变化及其对AgNPs的吸附能力,通过序批式试验,探究不同浓度AgNPs对A.flavus TL-F3生长、细胞形态、胞外聚合物(EPS)分泌、抗氧化系统和吸附能力的影响。研究发现,AgNPs可抑制A.flavus TL-F3生长,且抑制效果与浓度正相关。AgNPs可致A.flavus TL-F3菌丝发育不完全,表面破损。与不加AgNPs的对照组相比,当AgNPs的质量浓度为80 mg·L^(-1)时,胞外聚合物含量升至237.55 mg·g^(-1),丙二醛含量、超氧化物歧化酶活性、还原性谷胱甘肽含量均显著(P<0.05)提高,而Na^(+)K^(+)-ATP酶活性显著(P<0.05)降低了50.37%。A.flavus TL-F3对AgNPs有一定的吸附能力,当AgNPs的质量浓度为1、30、50、80 mg·L^(-1)时,A.flavus TL-F3对AgNPs的吸附率可达68.54%以上。综上所述,A.flavus TL-F3可用于含Ag和AgNPs污染水体的修复。

Geographical distribution of Aspergillus flavus in peanut harvest period in China

In order to grasp the distribution of Aspergillus flavus in the soil of peanut production areas in China,A.flavus biomarkers were tested on 555 soil samples from 37 sampling points in 17 provinces,peanut fields in four agroecological zones(Southern area,Yangtze River Basin,Northern area,Northeast area).The results showed that(1)the cultivation amount of A.flavus per gram of soil in the Yangtze River Basin is 1.30 times that of the southern area,1.56 times that of the northern area,and 6.20 times that of the northeast area,with obvious regional characteristics.(2)In the Yangtze River basin,the change of longitude in the east-west direction has no direct impact on the cultivation amount of A.flavus per gram of soil.(3)In the east coast,the A.flavus cultivated per gram of soil increased first and then decreased with the increase of latitude from south to north.(4)A.flavus can be isolated in the soil samples above 1000 m.Field pollution is an important source of aflatoxin contamination in peanut.The study on the distribution of A.flavus in soil in China could provide theoretical support for the early warning and prevention and control measures of aflatoxin contamination in peanut.