海星共附生真菌Penicillium sp．GGF16－1－2中次级代谢产物研究

目的 全球天然产物社会分子网络（GNPS）和单菌株多次级代谢产物（OSMAC）策略从海洋微生物中寻找结构新颖、活性好的次生代谢产物。方法 在GNPS指导下，通过硅胶柱层析及半制备高效液相色谱（HPLC）等方法对海星共附生真菌penicillium sp. GGF16-1-2在不同培养基的次级代谢产物进行分离纯化。通过核磁共振（NMR）、高分辨质谱（HRMS）、旋光（ORD）和圆二色光谱（CD）等现代波谱解析方法以及对比文献确定化合物的结构。结果 在GNPS追踪指导下从penicillium sp. GGF16-1-2中D培养基分离得到9个聚酮类化合物，依次为phenol A（1）、decarboxydihydrocitrinone（2）、stoloniferol B（3）、sclerotinin A（4）、(1S,3R,4S)-1-(4"-hydroxyl-phenyl)-3,4-dihydro-3,4,5-trimethyl-1H-2- benzopyran-6,8-diol（5）、β-diversonolic ester（6）、sydowinin A（7）、ω-hydroxy-emodin（8）和dibutyl phthalate（9）。而在真1培养基中GNPS预测到二聚体类成分存在，并在GNPS指导下初步分离得到桔霉素二聚类化合物：citrinin H1（10）和dicitrinone B（11）。结论 OSMAC策略和GNPS可以预测并获得骨架丰富、结构新颖的化合物。对海星共附生真菌penicillium sp. GGF16-1-2次生代谢产物研究发现真1培养基比D培养基更适合桔霉素二（多）聚体类化合物的产生。     

恒山黄芪内生真菌Aspergillus sp.中环二肽的分离和鉴定

目的:研究黄芪内生真菌AR-15-1的环二肽类次生代谢产物的成分。方法:内生真菌AR-15-1是采用组织学方法分离自恒山黄芪的根部,真菌的鉴定采用形态学法结合分子生物学法,内生真菌大量发酵采用固体培养的方法,环二肽成分的分离使用柱色谱法,HPLC法结合LH-20羟丙基葡聚糖凝胶色谱进行分离纯化,化合物结构鉴定采用波谱表征分析。结果:从黄芪根部分离到的内生真菌AR-15-1被鉴定为曲霉属Aspergillus sp.,从AR-15-1的固体发酵物中分离到8个环二肽化合物,分别为环(脯-甘)二肽(1),环(脯-亮)二肽(2),环(脯-异亮)二肽(3),环(脯-缬)二肽(4),环(苯丙-甘)二肽(5),环(苯丙-丙)二肽(6),环(苯丙-络)二肽(7)和环(苯丙-脯)二肽(8)。结论:环二肽类化合物1~8均为首次从黄芪内生真菌中分离得到,其中大部分环二肽化合物已被发现是具有很好的生物活性。     

质谱导向的肾指海绵Reniochalina sp.中环肽类成分研究

目的 以质谱为导向对肾指海绵Reniochalina sp.中的环肽类成分进行研究。方法 采用质谱引导的程序性分离手段定向追踪并分离纯化海绵中的环肽类成分;通过理化常数测定、波谱数据比对确定化合物结构;利用CCK-8法对化合物进行初步细胞毒活性评价。结果 从肾指海绵Reniochalina sp.中分离获得3个环肽类化合物,分别鉴定为stylopeptide 1 (1)、hymenamide D (2)、axinastatin 2 (3)。化合物1对6种人肿瘤细胞株具有细胞毒性,IC₅₀值范围为6.09 ~ 17.26 μmol/L。结论 化合物1 ~ 3首次分离自Reniochalina属海绵,化合物1是细胞毒性环七肽。     

柳珊瑚共附生真菌Alternaria sp.(WZL003)抑菌化合物的分离及其作用机制初步研究D

目的研究1株柳珊瑚共附生真菌具有抑菌活性次级代谢产物及抑菌作用机制。方法采用活性追踪分离的方法,运用硅胶柱层析、Sephadex LH-20凝胶柱层析和半制备HPLC等手段,对采自中国南海的柳珊瑚Echinogorgia rebekka中分离获得的共附生链格孢霉属真菌Alternaria sp.(WZL003)的发酵产物进行分离和纯化,利用NMR、MS等波谱方法,并与文献对照,确定化合物的结构;以海洋病原菌和污损菌鳗弧菌Vibrio anguillarum为对象研究化合物的抑菌作用机制。结果从该菌发酵液的乙酸乙酯提取物中,分离获得1个对V.anguillarum具有较强抑菌活性的蒽醌类化合物macrosporin。结论初步的抑菌作用机制研究发现,该化合物能破坏鳗弧菌的细胞壁和细胞膜,导致细胞通透性增加,胞内大量内容物外泄,最终导致菌体死亡,从而起到抑菌作用。本研究首次报道了macrosporin对鳗弧菌的抑菌作用及其作用机制。     

Three Peptide Modulators of the Human Voltage-Gated Sodium Channel 1.7, an Important Analgesic Target,from the Venom of an Australian Tarantula

Voltage-gated sodium (Na_V) channels are responsible for propagating action potentials in excitable cells. Na_V1.7 plays a crucial role in the human pain signalling pathway and it is an important therapeutic target for treatment of chronic pain. Numerous spider venom peptides have been shown to modulate the activity of Na_V channels and these peptides represent a rich source of research tools and therapeutic lead molecules. The aim of this study was to determine the diversity of Na_V1.7-active peptides in the venom of an Australian Phlogius sp. tarantula and to characterise their potency and subtype selectivity. We isolated three novel peptides, μ-TRTX-Phlo1a, -Phlo1b and -Phlo2a, that inhibit human Na_V1.7 (hNa_V1.7). Phlo1a and Phlo1b are 35-residue peptides that differ by one amino acid and belong in NaSpTx family 2. The partial sequence of Phlo2a revealed extensive similarity with ProTx-II from NaSpTx family 3. Phlo1a and Phlo1b inhibit hNa_V1.7 with IC₅₀ values of 459 and 360 nM, respectively, with only minor inhibitory activity on rat Na_V1.2 and hNa_V1.5. Although similarly potent at hNa_V1.7 (IC₅₀ 333 nM), Phlo2a was less selective, as it also potently inhibited rNa_V1.2 and hNa_V1.5. All three peptides cause a depolarising shift in the voltage-dependence of hNa_V1.7 activation.     

多节孢属Nodulisporium sp.真菌中一个新的生物碱类化合物

多节孢属真菌代谢产物结构多样。该研究通过正相硅胶色谱、反相制备液相色谱等方法,从一株多节孢属真菌的固体发酵提取物中分离鉴定4个代谢产物,包括1个新化合物;根据理化性质和波谱数据,分别鉴定为2-羟基-1,1-二甲基-1,2,3,9-四氢-4H-咔唑-4-酮(1)、酪醇(2)、羟基酪醇(3)和羟基酪醇乙酸酯(4),其中1为新化合物。     

野生树鼩肠道蠕虫感染调查及分析

目的调查野生树鼩(Tupaia belangeri Chinensis)感染肠道蠕虫的主要种类并进行鉴定,为今后树鼩寄生虫检测提供形态学参考,为实验树鼩寄生虫控制提供依据。方法采集203只野外来源的树鼩新鲜粪便,虫卵采用常规粪便直接涂片以及孵化后显微镜观察;绦虫采用压片、固定染色,以及线虫经透明后体视镜观察,虫卵与成虫相对应鉴定。结果野生树鼩肠道蠕虫的总感染率为75.86%,主要感染种类有3种,经鉴定为长膜壳绦虫、奇口线虫和粪类圆线虫,感染率分别为27.67%,30.06%和51.52%。三种蠕虫的混合感染率为4.55%。两种线虫虫卵在树鼩粪便中多为含胚胎形态。结论野生树鼩肠道蠕虫的感染率较高。对野外引入的新种源必须隔离检疫,进行针对性的药物治疗,才能有效地控制肠道寄生虫病的传播。     

Identification of a functional dddD-Rh for dimethyl sulfide production in the Antarctic Rhodococcus sp. NJ-530

Dimethylsulfoniopropionate (DMSP) is widespread in the oceans, and its biological metabolite, dimethyl sulfide (DMS), plays an important role in the atmosphere. The Antarctic region has become a hotspot in DMS studies due to the high spatial and temporal variability in DMS(P) concentration, but the level of bacterial DMS production remains unclear. In this study, a bacterium isolated from Antarctic floating ice, Rhodococcus sp. NJ-530, was found to metabolize DMSP into DMS, and the rate of DMS production was measured as 3.96 pmol·mg protein⁻¹·h⁻¹. Rhodococcus sp. NJ-530 had a DddD-Rh enzyme containing two CaiB domains, which belonged to the CoA-transferase III superfamily. However, the DddD-Rh had a molecular weight of 73.21 kDa, which was very different from previously characterized DddD enzymes in sequence and evolution. In vitro assays showed that DddD-Rh was functional in the presence of acetyl-CoA. This was the first functional DddD from Gram-positive Actinobacteria. Moreover, a quantitative real-time polymerase chain reaction revealed that high temperature facilitated the expression of dddD-Rh, and changes of salinity had little effect on it. This study adds new evidence to the bacterial DMS production in the Southern Ocean and provides a basis for investigating the metabolic mechanism of DMSP in extreme environments.