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Sea cucumber-derived fungi have attracted much attention due to their capacity to produce an incredible variety of secondary metabolites. Genome-wide information on Aspergillus micronesiensis H39 obtained using third-generation sequencing technology (PacBio-SMRT) showed that the strain contains nonribosomal peptide synthetase (NRPS)-like gene clusters, which aroused our interest in mining its secondary metabolites. 11 known compounds ( 1 - 11 ), including two γ -aromatic butenolides ( γ -AB) and five cytochalasans, were isolated from A. micronesiensis H39. The structures of the compounds were determined by NMR and ESIMS, and comparison with those reported in the literature. From the perspective of biogenetic origins, the γ -butyrolactone core of compounds 1 and 2 was assembled by NRPS-like enzyme. All of the obtained compounds showed no inhibitory activity against drug-resistant bacteria and fungi, as well as compounds 1 and 2 had no anti-angiogenic activity against zebrafish.

Objective: To investigate the clinical significance of endothelin A receptor (ETAR) expression in high-grade serous ovarian carcinoma (HGSOC). To design ETAR carboxyl terminal (ETAR-C) amino acids derived polypeptide and to study the inhibitory effect on ovarian epithelial carcinoma cells in vitro. Methods: (1) A total of 126 patients who received surgical treatment and were diagnosed with HGSOC by postoperative pathological examination in Central Hospital of Xuzhou from January 1, 2007 to December 31, 2017 were selected. All patients had completed clinicopathological data and follow-up data. Cancer tissue samples were collected and ETAR mRNA expression in HGSOC tissues was detected by reverse transcript-PCR. The clinical significance was analyzed. (2) ETAR-C fusion polypeptide was designed based on the sequence of carboxyl terminal amino acids of ETAR, expressed and purified in vitro. The effects of ETAR-C fusion polypeptide on migration and invasion ability of ovarian cancer SKOV3 and CAOV3 cells were detected by scratch test and invasion test, respectively. The effect of ETAR-C fusion polypeptide on chemosensitivity of cisplatin-resistant ovarian cancer SKOV3/cDDP and CAOV3/cDDP cells was determined by methyl thiazolyl tetrazolium (MTT) colorimetric assay. The effect of ETAR-C fusion polypeptide on β-arrestin-1 expression in ovarian cancer SKOV3 and CAOV3 cells was detected by western blot. Results: (1) The relative expression level of ETAR mRNA in HGSOC tissues was 18.6±5.1. Patients with HGSOC were divided into high ETAR mRNA expression ( n =76) and low ETAR mRNA expression ( n =50) with 61.7% as cut-off value analyzed by X-Tile software. High expression of ETAR mRNA was significantly correlated with abdominal water volume, platinum drug resistance, and cancer antigen 125 (CA 125 ) value in HGSOC patients (all P <0.05), but was not related to the age of patients with HGSOC and the size of postoperative residual lesions (all P >0.05). The 5-year progression free survival rates were 18.4% and 28.0%, and the 5-year overall survival rates were 38.2% and 52.0% in HGSOC patients with high and low ETAR mRNA expression respectively, there were statistically significant differences ( P =0.046, P =0.034). (2) The results of scratch test and invasion test showed that the scratch healing rate and cell invasion rate of SKOV3 or CAOV3 cells treated with endothelin-1 (ET-1) and ET-1+ETAR-C were respectively compared, and the differences were statistically significant (all P <0.05). MTT assay showed that the inhibition rates of ETAR-C fusion polypeptide treated in SKOV3/cDDP and CAOV3/cDDP cells were significantly higher than those of control cells after the addition of 4, 6, 8, 10, 12, and 24 μg/ml cisplatin (all P <0.05). Western blot analysis showed that the relative expression levels of β-arrestin-1 in SKOV3 or CAOV3 cells treated with ET-1 and ET-1+ETAR-C were 1.85±0.09 and 1.13±0.09 (SKOV3 cells), 2.14±0.15 and 1.66±0.12 (CAOV3 cells), respectively. The differences were statistically significant (all P <0.05). Conclusions: The prognosis of HGSOC patients with high expression of ETAR mRNA is significantly worse than those with low expression of ETAR mRNA. ETAR might be a new target for HGSOC treatment. The ETAR-C fusion polypeptide that interferes with the interaction of ETAR and β-arrestin-1 has good inhibitory effect on ovarian cancer cells in vitro, and might have clinical application potential.

To improve the naringinase production of Aspergillus tubingensis UA13, shorten the fermentation period, and verify its industrial application value, naringinase production conditions were optimized, and 5 L scale-up study in stirred tank bioreactor was carried out. Parameters, including carbon, nitrogen sources and inducer, optimal seed age, inoculum amount, temperature and pH, were adjusted and optimized in shaking flask. Keeping pH at the optimal value 6 in bioreactor, dissolved oxygen was monitored during the fermentation and the optimal stirring rate was investigated. In 5 L scale-up study, the highest naringinase activity was 72.62 U/mL, which was 1.75 times higher than that (41.52 U/mL) in shaking flask and the fermentation period was shortened by 24 h.

Naringinase was mainly obtained by microbial fermentation, and mutagenesis was a major way for obtaining excellent mutants. The aim of this study was to screen out a high naringinase yielding mutant to enhance the potential application value of its industrialization and compare the effects of different mutagenic methods on the enzyme activity of the strain. A novel producing naringinase strain, Aspergillus tubingensis MN589840, was isolated from mildewed pomelo peel, later subjected to mutagenesis including UV, ARTP and UV-ARTP. After five rounds iterative mutagenesis, the mutants U1, A6 and UA13 were screened out with 1448·49, 1848·71, 2475·16 U mg -1 enzyme activity, the naringinase productivity raised by 79·08, 123·56 and 206%, respectively. In addition, the naringinase activity of three mutants rose after each round of iterative mutagenesis. These results indicated that the mutagenesis efficiency of UV-ARTP was higher than that of single ARTP, and both are better than UV. In summary, the iterative UV-ARTP mutagenesis is an effective strategy for screening high naringinase-producing strains., (© 2020 The Society for Applied Microbiology.)

This study was performed to describe the clinical features, risk factors, and treatment methods of uterine torsion in pregnancy. The most common symptoms are abdominal pain, fetal heart rate changes, and failure of cervical dilatation and are often accompanied by complete or partial placental abruption. Preoperative diagnosis is challenging even with the use of ultrasound. Uterine torsion in the third trimester is correlated with the presence of multiple uterine fibroids. The causes of gravid uterine torsion vary and the clinical manifestations are nonspecific. Early diagnosis and improved detection approaches are the keys to treatment of patients with uterine torsion. However, the preoperative diagnosis remains difficult and the diagnosis is often made during cesarean section.

Three new lupane-triterpenoids (1-3) along with six known compounds (4-9) were isolated from the ethanolic extract of whole plant of Potentilla discolor Bunge. The structures of Compounds 1-3 were established by extensive 1D and 2D NMR together with other spectrum analysis, indicating that their C-27 positions were highly oxygenated, which were rarely found in nature. Their in vitro anti-proliferative activities against HepG-2, MCF-7 and T-84 cell lines were evaluated by Cell Counting Kit-8 (CCK-8) assay, and the results showed different activities for three cell lines with IC50 values ranging from 17.84 to 40.64 μM. In addition, the results from Hoechst 33258 and AO/EB staining as well as annexinV-FITC assays exhibited Compound 1 caused a markedly increased HepG-2 cellular apoptosis in a dose-dependent manner. The further mechanisms of Compound 1-induced cellular apoptosis were confirmed that 1 induced the production of ROS and the alteration of pro- and anti-apoptotic proteins, which led to the dysfunction of mitochondria and activation of caspase-9 and caspase-3 and finally caused cellular apoptosis. These results would be useful in search for new potential antitumor agents and for developing semisynthetic lupane-triterpenoid derivatives with high antitumor activity.

Objective: To get active secondary metabolites from the fungus Paecilomyces sp.., Methods: The strain Paecilomyces sp. was further grown in solid-substrate fermentation cultures, the metabolites were got by application of different separation techniques, such as silica gel, Sephadex LH-20 column chromatography, and reversed-phase high performance liquid chromatography. Their structures were identified by comprehensive spectroscopic methods., Results: Four compounds were isolated and identified as Cerebroside C (1), Cerebroside D (2), 2-Hydroxybenzyl alcohol (3), 2-(4-Hydroxyphenyl) ethanol., Conclusion: Four compounds are isolated from Paecilomyces sp. for the first time.

Objective: The metabolites of HS-3 associated with holothurians were studied, which was identified by molecular biology as Alternaria sp.., Methods: The holothurians were gathered from the Sea of Zhifu Islet, Shandong Province. HS-3 Alternaria sp. was culternitived in potato medium, and four compound was got by TLC, chromatography and HPLC, and 1-hydroxyl-3-methylanthracene-9,10-dione (1), chrysophanol (2), sterigmatocystin (3) and cerebroside (4) were elucated by modern spectrum., Conclusion: All of this provides scientific data for further study of holothurians, and the four coumpouns are isolated from the microbe associated with holothurians for the first time.

Objective: To get active metabolites from the microbes associated with sea cucumber., Methods: Fungus was isolated from the sea cucumber, and the species was identified by molecular biology, and then was cultivated in GYP medium, and the metabolites were got by chromatography. Their structures were identified by comprehensive spectroscopic methods., Results: Fungus HS-1 Epicocum sp. was isolated from the sea cucumber in Weihai, Yellow Sea. Four compounds were got as 5-methyl-6-hydroxy-8-methyoxy-3-methylisochroman (1), 8-hydroxy-3-methylisochroman-1-one (2), peroxy-ergosterol (3) and succinic acid (4)., Conclusion: Fungus HS-1 Epicocum spp. is first isolated from the sea cucumber sample, this research provides new idea for further development of sea cucumber.

Objective: The secondary metabolites of the fungus ZZF13 isolated from the leaves of the mangrove sample Kandelia candel in Zhanjiang and Guignardia sp. 4382 isolated from bark of Kandelia candel (endophyte) of Mai Po, Hong Kong were studied., Methods: The compounds were isolated by siliga gel, and their structures were identified by IR, MS and NMR., Results: Four compounds were isolated from the culture of this strain. Their structures were identified as Bacillpsporin C (1), 5-carboxymellein (2), 5-methylmellein (3) and 1-(2,6-dihydroxyphenyl) butanone (4)., Conclusion: The compounds 2 - 4 are isolated from the Guignardia sp. of Marine fungi for the first time.

The anticancer activities of secalonic acid D separated from the secondary metabolites of the mangrove endophytic fungus No. ZSU44 were investigated in this study. Secalonic acid D showed potent cytotoxicity to HL60 and K562 cells, and the IC(50) values were 0.38 and 0.43 mumol/L, respectively. Annexin V-FITC/PI assay and western blot indicated that secalonic acid D induced apoptosis in HL60 and K562 cells. In addition, secalonic acid D led to cell cycle arrest of G(1) phase related to downregulation of c-Myc. Moreover, our data indicated that downregulation of c-Myc and cell cycle arrest of G(1) phase were caused not by formation of G-quadruplex structures but by activation of GSK-3beta followed by degradation of beta-catenin.

Two new natural products, tenelate A (1) and B (2), together with the known compound, tenellic acid C (3), were isolated from the mangrove endophytic fungus Talaromyces sp. (SBE-14), from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR techniques.

Aim: To investigate the antioxidant activity of chito-oligosaccharides (COSs) on pancreatic islet cells in diabetic rats induced by streptozotocin., Methods: The antioxidant effect of COSs on pancreatic islet cells was detected under optical microscopy and with colorimetric assay and gel electrophoresis. The activities of glutathione peroxidase and superoxide dismutase, total antioxidant capacity, and content of malondialdehyde in serum and tissue slices of pancreas were examined after 60 d to determine the effect of COSs in streptozotocin-induced diabetes in rats., Results: COSs can prohibit the apoptosis of pancreatic islet cells. All concentrations of COSs can improve the capability of total antioxidant capacity and activity of superoxide dismutase and decrease the content of malondialdehyde drastically. Morphological investigation in the pancreas showed that COSs have resulted in the reduction of islets, loss of pancreatic cells, and nuclear pyknosis of pancreatic cells., Conclusion: COSs possess various biological activities and can be used in the treatment of diabetes mellitus.

One new compound 6-demethylvermistatin (1), together with two known compounds, the penicillide derivatives (2) and (3) were isolated from the mangrove fungus Guignardia sp. No. 4382 obtained from the South China Sea. Their structures were assigned using high-resolution electron ionization mass spectrometry(HREIMS), (1)H and (13)C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. The absolute configuration of 1 was established by comparison of its CD with that of vermistatin., (Copyright (c) 2008 John Wiley & Sons, Ltd.)

We report the unambiguous assignments of the (1)H and (13)C NMR spectra of two new natural products, namely, 1,4,5,6,7,9-hexahydroxy-2-methoxy-7-methyl-5beta,9beta,8abeta, 6alpha,10aalpha-hexahydroanthracen-10 (10aH)-one (1) and 1,4,6-trihydroxy-2-methoxy-7-methylanthracene-9, 10-dione (2), together with three known anthraquinones. These compounds were all isolated from the marine endophytic fungus No. 1403 collected from the South China Sea. Compounds 3 and 4 were isolated from the marine fungus for the first time. The structures were elucidated by the spectroscopic methods 1D and 2D NMR including COSY, HMQC, HMBC and NOE, and HREIMS. In our cytotoxicity assays, compound 5 showed cytotoxicity toward KB and KBv-200 cells with IC(50) of 1.40 and 2.58 microg/ml, respectively. In addition, the plausible biogenic relationship of compounds 1, 2, 3 and 4 is discussed., ((c) 2007 John Wiley & Sons, Ltd.)

A novel nitro-phenyl glucoside (1) was isolated from mangrove endophytic fungus (fungus B60), collected from the Shenzhen mangrove Acanthus ilicifolius linn. Four related nitro-phenyl compounds (2-5) were also obtained, which were isolated for the first time as natural products. Their structures were established on the basis of NMR spectroscopic, mass spectrometric data and some chemical transformations. In the preliminary bioassay, compound 1 had a slight inhibitory effect on alpha-glucosidase with an IC(50) of 160.3 microM.

Anthracenedione derivatives are potent cytotoxic agents to tumor cells. In this study, we investigated the anticancer activities of anthracenedione derivative 1403P-3 separated from the secondary metabolites of the mangrove endophytic fungus No. 1403. Our results demonstrated that 1403P-3 showed potent cytotoxicity not only to human epidermoid carcinoma drug-sensitive parental KB cells but also to multidrug resistant (MDR) KBv200 cells and the IC50 values were 19.66 and 19.27 muM, respectively. Further research indicated that 1403P-3 induced apoptosis in KB cells and KBv200 cells confirmed by Hoechst 33258 staining, detection of DNA fragmentation and cleavage of poly (ADP-ribose) polymerase (PARP). Furthermore, apoptosis triggered by 1403P-3 was characterized by the loss of mitochondrial membrane potential (DeltaPsi(m)), release of cytochrome c, cleavage of Bid, and activation of caspases-2, -3, -7, -8 and -9. Z-IETD-FMK, caspase-8 inhibitor could inhibit the activation of caspase-2 and cleavage of Bid induced by 1403P-3. However, activation of caspase-9 and cleavage of PARP caused by 1403P-3 were not inhibited by Z-IETD-FMK. Additionally, 1403P-3 did not influence the expression level of Bcl-2 and Bax. It is noteworthy that 1403P-3 decreased the generation of reactive oxygen species (ROS) in KB cells and KBv200 cells. DNA binding assay exhibited that apoptosis induced by 1403P-3 was not involved in intercalating to DNA. In summary, 1403P-3 induced apoptosis of KB cells and KBv200 cells through mitochondrial pathway and death receptor pathway. Furthermore, the mitochondrial pathway was independent of reactive oxygen species and activation of caspase-8.

A new chloro-monoterpene (compound 1) and three known compounds, peroxyergosterol, uracil and methylisocoumarin, were isolated from the ethyl acetate extract of the fermentation broth of the mangrove endophytic fungus Tryblidiopycnis sp. (4275) obtained from Kandelia woody tissue from Mai Po, Hong Kong. Its structure was determined spectroscopically and by X-ray crystallographic analysis.