Extraction and isolation

This study aimed to quantify the phenolic contents and the antioxidant capacities of leaf extract powders from three Myrtaceae plants, namely Cleistocalyx operculatus (Vietnamese name: Vối), Psidium guajava (Ổi), and Rhodomyrtus tomentosa (Sim), investigate their inhibitive activities on the growth of bacteria isolated from spoiled shrimps, and evaluate their values as preservative agents in the cold storage of Pacific whiteleg shrimps (Penaeus vannamei).

15p vibecca 01-10-2024 2 1   Download

Seven known compounds, including two neolignans, four lignans, and one flavane were isolated from the methanol extract of Pandanus tonkinenis fruits. Their structures were determined to be ficusal, vladinol F, medioresinol, syringaresinol, lariciresinol, secoisolariciresinol, and luteoliflavan by analysis of MS and NMR data as well as by comparison of their spectral data with those reported in the literature.

7p dianmotminh02 03-05-2024 4 2   Download

This study aimed to isolate and identify marine fungi from Bai Tu Long Bay and assess their antimicrobial potential. We successfully isolated twenty strains of marine-derived fungi. The crude extracts from these fungi were tested against pathogenic microorganisms. All twenty strains exhibit some degree of growth inhibition against the tested microorganisms.

9p dianmotminh02 03-05-2024 5 2   Download

The methanol extracts as well as some compounds from this plant exhibited anti-inflammatory, antimicrobial activity, antioxidant, hepatoprotective and anti-cancer effect, and antiosteoporotic. On going to search for bioactive components from the Vietnamese plant, this paper reported the isolation of seven phenolic compounds including one new from the aerial parts of A. ilicifolius. The cytotoxic activity of the isolates against two cancer cell lines (HepG2 and SK-LU1) were also screened and reported herein.

5p dianmotminh02 03-05-2024 8 2   Download

From CHCl3-soluble extract of the leaves of Taxus wallichiana (Taxaceae), collected in Lam Dong Province, five compounds were isolated and identified as sciadopitysin, ginkgetin, (S)-(+)-rhododenol, (+)-erythro-N-benzoyl3-phenylisoserine methyl ester, and (−)-α-conidendrin (5). Their chemical structures were determined by 1D and 2D NMR spectra and comparison with published data. Except for (−)-α-conidendrin, these remaining compounds were first reported of Taxus wallichiana.

6p dianmotminh02 03-05-2024 9 4   Download

The present study investigated the phytochemical and biological properties of the rhizomes C. aromatica. From the CHCl3 extract of C. aromatic rhizomes, six known compounds, including (-)-hannokinol, (3R,5R)-3,5-diacetoxy-1,7-bis(4- hydroxyphenyl)heptane, naringenin, 2-(4- (hydroxymethyl)phenyl)propan-2-ol, 5-hydroxymethylfurfural, and bisacurone, were isolated. All compounds were tested on the biological inhibitory activities against tyrosinase, αglucosidase, and urease. It was the first time all compounds were isolated from rhizomes of C. aromatica Salisb.

6p dianmotminh02 03-05-2024 4 3   Download

The optimum subcritical water extraction condition was obtained at 120 ºC in 45 min. Better functional properties were observed in subcritical water extraction products that indicated this method can be applied as a novel alternative technique to modify the properties of rice proteins isolate for the functional purposes in future.

5p mudbound 10-12-2021 15 1   Download

Green synthesis method is being increasingly used in the development of safe, stable, and eco-friendly nanostructures with biological resources. In this study, extracellular and intracellular synthesis of gold nanoparticles (AuNPs) was carried out using green algae Chlorella sorokiniana Shihira & R.W. Fresh algae were isolated and identified from Musaözü Pond located in the province of Eskişehir and then extraction process were performed.

18p thiencuuchu 27-11-2021 10 2   Download

Objectives of the study: Survey of biological activity of alkaloid isolated from hairy roots of E.longifolia to find new activities. Determining optimal culture conditions for E.longifolia hairy roots to grow and develop. Determining the concentration of three elicitors (Salicylic acid, Jasmonic acid and Yeat extract) on the production and accumulation of alkaloids isolated from hairy roots of E.longifolia in vitro.

26p extraenglish 24-05-2021 30 5   Download

The research objectives of the thesis: Research to isolate, determine chemical structure and probe the biological activity of chemical components in apple and Docynia indica fruits; Research to optimize the extraction technology process to create products from Docynia indica fruits

27p extraenglish 24-05-2021 27 4   Download

Research to isolate, determine chemical structure and probe the biological activity of chemical components in apple and Docynia indica fruits; Research to optimize the extraction technology process to create products from Docynia indica fruits.

27p capheviahe27 23-02-2021 42 4   Download

Develop the process of producing crude extracts, fractions and pure chemical compounds isolated from E. fortunei; tudy of inhibitory effect of the crude ethanol extracts from E. fortunei on the growth of M.aeruginosa and evaluating their ecological safety to non-target aquatic organisms.

28p larachdumlanat129 20-01-2021 28 3   Download

The maceration was applied to the seeds of the plant to afford the crude extract which was then fractionated by liquid-liquid extraction to obtain the ethyl acetate extract. The extract was carried out by using normal phase silica gel column chromatography and thin-layer chromatography. Analysis of spectroscopic data including HR-ESI-MS, 1D and 2D-NMR and a comparison of the NMR data with that in the literature led to the structural elucidation of isolated compounds.

4p larachdumlanat127 02-01-2021 11 1   Download

From the methanol extract of dried powders of Hedyotis diffusa Willd. (Rubiaceae) plant growing in Tuyen Quang Province, three compounds were isolated and identified: B-sitosterol, daucosterol and ursolic acid. Their structures were confirmed by various spectral methods (IR, NMR, MS, 1H-NMR, 13C-NMR, etc.) and by comparison with those of references.

5p larachdumlanat127 20-12-2020 29 3   Download

Smilax glabra Roxb. is a medicinal plant of Vietnam to treat several diseases such as: Piercing pain in the bones, detoxicating, scabies, nephritis, cystitis, syphilis,... From ethanol extracts of Smilax glabra Roxb. cultivating in Thai Nguyen, 5 compounds were isolated and structurally elucidated in the first time by various spectral methods, such as IR, MS, 1H-NMR, 13C-NMR, DEPT, HSQC, HMBC.

9p larachdumlanat127 20-12-2020 19 3   Download

Four compounds as B-sitosterol, 1,8-dihydroxy-3-methoxy- 6-methylanthraquinone (physcion), ursolic acid and 2α,3α,19- trihydroxyurs-12-ene-28-oic acid (euscaphic acid) were isolated from the ethanolic extract of the Rubus alceaefolius leaves growing in Vietnam. Their chemical structures were identified by IR, ESI-MS, 1D and 2D NMR spectral.

7p larachdumlanat127 20-12-2020 19 2   Download

From the ethanol extract of dried powders of Andrographis paniculata Nees leaves growing in Hung Yen Province, five compounds were isolated and identified: Andrographolide, dodecahexanoic acid, B-sitosterol, a mixture of 14-deoxy-11,12-didehydroandrographolide and 14-deoxyandrographolide (in ratio of 11:5).

7p tamynhan5 10-12-2020 8 2   Download

Study on the chemical constituents of methanol extract from leaves of Moringa oleifera Lam. (Moringaceae) has resulted in the isolation of four compounds: Vitexin, isoquercitrin, tricosanol and tetradecanoic acid. Their structures were determined by spectroscopic methods.

5p tamynhan9 02-12-2020 27 3   Download

Recently, we collected fruit bodies of Ganoderma neo-japonicum in Lamdong Province and found that the EtOAc crude extract obtained, having an IC50 value of 19.14 µg/mL, shows strong cytotoxicity against the KB cell line. This paper describes the isolation and cytotoxicity of four compounds from this mushroom.

5p tamynhan8 04-11-2020 19 1   Download

Investigation on the chemical constituents of ethyl acetate extract from leaves of Taxus wallichiana Zucc. (Taxaceae), collected in Ha Giang province, has resulted in the isolation of three metabolites for the first time: sciadopitysin (1), β-sitosterol (2), and isoquercitrin (3). Their structures were determined by spectroscopic methods.

6p koxih_kothogmih5 04-09-2020 25 2   Download