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The marine environmental conditions are particularly different from terrestrial ones; recent studies have showed that marine actinomycetes might produce many novel compounds with good biological activity. The objective of this study is to isolate and screen actinomycetes strains from the marine environment with activity against pathogenic microorganisms. Fifty strains of actinomycetes were isolated from 40 samples including: sediments, sponges, soft corals, echinoderms... collected from Van Phong Bay area of Khanh Hoa province, Vietnam. The strains fermented in A+ medium and fermentation broths were extracted 5 times with ethyl acetate. The extracts were evaporated under reduced pressure to yield crude extracts. Quantitative assay was used to determine MIC (minimum inhibitory concentration) of extract against 7 test strains, including three Gram-negative bacteria (Escherichia coli ATCC25922, Pseudomonas aeruginosa ATCC27853, Salmonella enterica ATCC13076), three Gram-positive bacteria (Enterococcus faecalis ATCC29212, Staphylococcus aureus ATCC25923, Bacillus cereus ATCC 14579), and the yeast Candida albicans ATCC10231. The result of screening showed that: 18/50 strains have shown the antibacterial activities against at least 3 strains of tested microorganisms. In which, strains G650, G654, G657, G666, G675 inhibited three Gram-positive test microorganisms at MIC values from 8 to 64 µg/mL and C. albicans ATCC10231 with MIC values from 2 to 16 µg/mL. In addition, the two strains G657 and G666 had inhibitory effect on P. aeruginosa ATCC27853 và S. enterica ATCC13076 with MIC value 128 µg/mL. Morphological and phylogenetic investigations based on 16S rRNA gene sequences of the selected five strains showed that: strain G650 belonged to species Streptomyces ardesiacus and strain G666 high similarity to the genus Streptomyces; strain G654 showed the highest similarity to the Salinispora arenicola species; strain G657 highest similarity to the Micromonospora aurantiaca; whereas G675 belonged to the Nocardiopsis flavescens species.

Marine ecosystems cover about 70% of the planet surface and are still an underexploitedsource of useful metabolites. Among microbes, filamentous fungi are captivating organisms used for the production of many chemical classes of secondary metabolites used in various fields such as medicine, food ...The present study was focused on the collection, isolation and screening of fungi with antibacterial activity from 25 marine fungi strains isolated by concentration dilution method from 16 samples including marine organisms and sediments collected in Bai Tu Long, Vietnam. The strains were cultured in PDA medium and the culture broths were extracted by ethyl acetate and vacuum rotary evaporation to produce crude extracts. Antimicrobial activity of the extracts was carried out on 7 tested microorganisms, including three Gram-negative bacterial strains (Escherichia coli ATCC25922, Pseudomonas aeruginosa ATCC27853, Salmonella enterica ATCC13076), three Gram-positive strains (Enterococcus faecalis ATCC29212, Stapphylococus aureus ATCC25923, Bacillus cereus ATCC14579), and yeast Candida albicans ATCC10231. The screening results showed thatfour strains with the highest antibacterial activity (M403, M583, M584 and M612) were capable of inhibiting 4 of the 7 tested microorganisms with minimum inhibitory concentration (MIC) from 32 to 256 µg/mL depending on each tested strain. Specifically, all M403, M583, M584 and M612 inhibited C. albicans ATCC10231 with MIC values ​​of 32-32-64-128 µg/mL, respectively. In addition, all four strains showed inhibitory activity against all three Gram-positive strains tested with MICs from 64 to 256 µg/mL. The strains were identified by morphology and 18S rRNA gene sequences. The results showed that 18S rRNA gene sequences of strains hadover 99% similarity with the 18S rRNA gene sequences available on the Genebank database. Strain M403 was most closely related Aspergillus versicolor and M584 was most closely related Aspergillus unguis, whereas M583 was most closely related Talaromyces purpureogenus and M612 identified as a member Penicillium chrysogenum. The sequences of 18S rRNA gene of four strains were registered on GenBank database with accession numbers: M403 (MW479130), M583 (MW479131), M584 (MW015805) và M612 (MW015801). Preliminary results showed that the marine environment has great potential for isolating fungal strains which contain antibacterial and other bioactive substances.

Five undescribed oleanane triterpene glycosides named chryroxosides A–D (1–5), together with five known compounds (6–10) were isolated from the leaves of Chrysophyllum roxburghii G.Don. Their chemical structures were elucidated by extensive spectroscopic data analyses including IR, HR-ESI-MS, 1D and 2D NMR). Compounds 1, 3, and 5 showed cytotoxic effects against KB, HepG2, HL60, P388, HT29, and MCF7 cell lines with the IC50 values ranging from 14.40 to 52.63 μM compared to the positive control compound (ellipticine) with the IC50 values ranging from 1.34 to 1.99 μM.

One new phenylpropanoid glycoside, myxosmoside I (1) and six known compounds, arenarioside (2), verbacoside (3), 3-formylindole (4), 5-hydroxymethyl furfural (5), D-manitol (6), and glycerol monooleate (7) were isolated from the roots of Myxopyrum smilacifolium (Wall.) Blume. Their chemical structures were determined by 1D-, 2D-NMR, and mass spectra, chemical methods, and compared with those reported in the literature. All compounds were evaluated for α-glucosidase inhibitory effect. Among them, phenylpropanoid glycosides 1-3 significantly inhibited α-glucosidase activity with IC50 values of 30.0 ± 0.9, 66.6 ± 2.3, and 36.9 ± 2.0 µM, respectively.

Actinomycetes has been extensively studied due to its ability to produce secondary compounds with high application value. Especially their antibiotic ability, more than 40% of antibiotics are derived from actinomycetes of which genus Streptomyces predominates. Moreover, marine actinomycetes have been being of great interest in recent years due to their ability to produce bioactive substances capable of providing diverse and novel chemical structures. In this study, from 8 samples of marine sediments collected in Vung Ang bay in Ha Tinh provinces, we have isolated 20 strains of actinomycetes. The strains were fermented in A1+ medium, the fermentation fluid was extracted 5 times with ethyl acetate, recovered sediment and determined antibacterial and cytotoxic activity. From the screening results, two strains with the highest antibacterial activity and highest cytotoxicity were selected ie., HT03 and HT06. Both strains had antagonistic activity of Enterococcus faecalis ATCC29212 with MICHT03= 32 μg/mL, MICHT06= 16μg/mL, with Stapphylococus aureus ATCC25923 with MICHT03= 64 μg/mL, MICHT06= 32 μg/mL and with Bacillus cereus ATCC 13245 has the same MIC = 16 μg / mL. In addition, the two strains HT03 and HT06 were able to strongly inhibit the yeast Candida albicans ATCC10231 with MICHT03= 16 μg/mL, MICHT06= 8 μg/mL. Especially, two strains, HT03 and HT06, exhibited very good toxicity on all 5 cancer cell lines (MCF-7 breast cancer cell; MDA-MB-231 breast cancer cell; lung cancer cell). NCI-H1975; HeLa cervical cancer cell; AGS gastric cancer cell) at both test concentrations of 30 µg/mL and 100µg/mL. By the analysis of 16S rRNA sequence, the results showed that the HT03 strain had the highest similarity (99.93%) to that of Streptomyces fradiaes and Streptomyces fradiae ATCC. The HT06 strain was defined to belong to Nocardiopsis synnemataformans with the 16S sequence identity of 99.89% to the Japanese standard Nocardiopsis synnemataformans DSM 44143 strain NBRC-102581.

Four new dihydrostilbene glycosides, assastilbosides A–D (1-4), along with seven known compounds, 5,4′-dihydroxydihydrostilbene 3-O-β- d -glucopyranoside (5), 3,5-dihydroxydihydrostilbene 4′-O-β- d -glucopyranoside (6), 3,5-dihydroxydihydrostilbene 4′-O-[6′′-O-(4′′′-methoxy)galloyl]-β- d -glucopyranoside (7), 3,5-dimethoxydihydrostilbene 4′-O-α- l -rhamnopyranosyl-(1→6)-β- d -glucopyranoside (8), (­)-epicatechin (9), (­)-epicatechin 3-O-gallate (10), and (-)-epigallocatechin 3-O-gallate (11) were isolated from methanol extract of the leaves of Camellia sinensis var. assamica (J.W.Mast.) Kitam. Their structures were elucidated by HR-ESI-MS, 1D- and 2D-NMR spectra and compared with NMR data in the literature. In addition, all isolated compounds were screened by α-glucosidase assay. Compounds 10 and 11 showed significant inhibitory α-glucosidase with IC50 values of 18.3 ± 1.1 and 21.9 ± 0.8 μM, respectively.

Three undescribed dihydrostilbene glycosides, 3,5-dihydroxyldihydrostilbene 4'-O-[6''-O-(4'''-hydroxylbenzoyl)]-β-D-glucopyranoside (1), 3,5-dihydroxyldihydrostilbene 4'-O-(6''-O-galloyl)-β-D-glucopyranoside (2), and 3,5-dihydroxyldihydrostilbene 4'-O-[6''-O-(3''',4'''-dimethoxyl)galloyl]-β-D-glucopyranoside (3), and seven known compounds, kaempferol 3-O-β-D-glucopyranoside (4), isoquercitrin (5), kaempferol 3-O-α-L-rhamnoside (6), quercitrin (7), (6S,9R)-roseoside (8), (-)-epicatechin 3-O-gallate (9), and (-)-epigallocatechin 3-O-gallate (10) have been isolated from the methanol extract of the leaves of Camellia sinensis var. assamica (J.W.Mast.) Kitam. (synnonym of Camellia assamica (Mast.) H.T.Chang) (Theaceae). Their structures were elucidated by spectroscopic methods (1 D-, 2 D-NMR) and mass spectra. All compounds were evaluated for cytotoxic activity against human oral cancer (CAL27) and human breast cancer (MDAMB231) cell lines. Compound 10 showed significant cytotoxic activity against CAL27 and MDAMB231 cell lines with IC50 values of 9.78 ± 0.25 and 3.27 ± 0.18 μM, respectively, compared to those of positive control, capecitabine (IC50 values of 8.20 ± 0.75 and 5.20 ± 0.89 μM).

Để tăng cường đẩy mạnh công tác tuyên truyền, phổ biến kiến thức về mục đích nhânđạo, chữa bệnh, giảng dạy, nghiên cứu khoa học và ý nghĩa của việc hiến, lấy, ghép mô, bộphận cơ thể người đến đội ngũ cán bộ Hội Chữ thập đỏ Việt Nam các cấp và các tầng lớpnhân dân, qua đó góp phần nâng cao nhận thức, thay đổi hành vi tiến tới đăng ký và hiếntặng mô, bộ phận cơ thể người khi còn sống hoặc sau khi chết, chết não; Bộ Y tế và Trungương Hội Chữ thập đỏ Việt Nam triển khai xây dựng Chương trình phối hợp Công tác tuyêntruyền, vận động hiến mô, bộ phận cơ thể người và hiến xác giai đoạn 2015 - 2020 tầm nhìnđến 2030 làm cơ sở cho việc triển khai hoạt động truyền thông vận động hiến tặng mô, bộphận cơ thể người nêu trên trong cả nước

Biến đổi khí hậu là một cụm từ dùng để chỉ sự thay đổi của hệ thống khí hậu gồm khí quyển, thủy quyển, sinh quyển, thạch quyển ở hiện tại và trong tương lai bởi các nguyên nhân khách quan và chủ quan trong một giai đoạn nhất định

Dịch bệnh này gây ra tổn thất lớn về con người và tài sản cho toàn bộ người dân và các chính phủ.Việt Nam cũng là một quốc gia hứng chịu tổn thất nặng lề do đại dịch. Để phòng, chống dịch, Chính phủđã áp dụng nhiều phương pháp và ban hành nhiều chính sách để phòng chống dịch Covid 2. Một trongnhững chính sách giai đoạn đầu của đại dịch là áp dụng giãn cách xã hội theo chỉ thị số 16/CT-TTg3 của thủtướng chính phủ. Để thực hiện chỉ thị số 16 được tốt nhất, văn phòng chính phủ đã ra văn bản số2601/VPCP-KGVX4 hướng dẫn thực hiện chỉ thị số 16 của Thủ Tướng.

Three new furostane saponins, ramofurosides A-C (1-3), and two known saponins, fistulosaponin B (4) and (25R)-26-O-β-D-glucopyranosyl-1β,3β,26-trihydroxyfurosta-5,20(22)-diene-1-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (5) were isolated from the methanol extract of Allium ramosum seeds. Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for reduction of lipid accumulation in HepG2 cell lines. As a result, compounds 1 and 3 showed a significant reduction in total lipid content by 27.93±3.05 and 27.54±1.68 %, respectively, at a concentration of 100 μM.