Natural Products Research Unit

Oyo, Nigeria

Natural Products Research Unit

Oyo, Nigeria
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Sribuhom T.,Natural Products Research Unit | Boueroy P.,Khon Kaen University | Hahnvajanawong C.,Khon Kaen University | Phatchana R.,Khon Kaen University | Yenjai C.,Natural Products Research Unit
Journal of Natural Products | Year: 2017

Seven new benzoyltyramines, atalantums A-G (1-7), and five known compounds were isolated from the peels of Atalantia monophylla. All compounds were examined for cytotoxicity against the cholangiocarcinoma cell lines KKU-M214, KKU-M213, and KKU-M156. Compound 5 exhibited the strongest cytotoxicity against KKU-M156 cells, with an IC50 value of 1.97 ± 0.73 μM, an approximately 4.7-fold higher activity than that of the ellipticine standard. Compound 1 displayed strong cytotoxicity against KKU-M214 cells, with an IC50 value of 3.06 ± 0.51 μM, nearly equal to that of the 5-fluorouracil standard. In the case of the KKU-M213 cell line, compounds 2, 4, and 11 exhibited stronger cytotoxicity than the ellipticine standard, with IC50 values of 2.36 ± 0.20, 5.63 ± 0.22, and 2.71 ± 0.23 μM, respectively. Compounds 1, 5, and 7 displayed cytotoxicity against KKU-M214 cells, with IC50 values of 3.06 ± 0.51, 8.44 ± 0.47, and 7.37 ± 1.29 μM, respectively. © 2017 The American Chemical Society and American Society of Pharmacognosy.

Tangjitjaroenkun J.,Chulalongkorn University | Chavasiri W.,Natural Products Research Unit | Yompakdee C.,Chulalongkorn University
Journal of Essential Oil Research | Year: 2012

Zanthoxylum limonella Alston is commonly used plant in Thailand for flavoring of foods and in traditional medicine. In this study, we investigated the crude essential oil, the distilled fractions thereof and the three pure major compounds of the oil from Z. limonella fruits for antibacterial activities against several bacteria including multi-drug resistant bacteria. The essential oil fractions I and II, and sabinene, the major compound of fractions I (54%) and II (41%), showed antibacterial activity against both Gram-positive and Gram-negative bacteria tested, except Pseudomonas aeruginosa. The crude oil showed higher antibacterial activity than sabinene against all tested bacteria, suggesting the presence of potent minor compound(s) with an additive effect, or less potent compound(s) with a synergistic effect among the components of the crude oil. The essential oil showed a potent killing effect, achieving a complete elimination of Staphylococcus aureus and Escherichia coli within a 9-minute exposure to a two-fold minimal bactericidal concentration level, while the multi-drug resistant bacteria, methicillin-resistant S. aureus and the extendedspectrum β-lactamase-producing E. coli, were completely eradicated within 90 minutes at the same dose. This is the first report on the essential oil from Z. limonella fruits against multi-drug resistant bacteria. The essential oil has potential uses in food preservation and as an antiseptic for medical use. © 2012 Taylor & Francis.

Hemtasin C.,Natural Products Research Unit | Ung A.T.,University of Technology, Sydney | Kanokmedhakul S.,Natural Products Research Unit | Kanokmedhakul K.,Natural Products Research Unit | And 3 more authors.
Monatshefte fur Chemie | Year: 2012

Alkaloid-like compounds containing a benzo[c]azepine core structure were successfully prepared in three steps from 5H-dibenzo[a,d]cyclohepten-5-ol via the bridging Ritter reaction. Biological studies of these compounds revealed that some of them are AChE inhibitors and antimalarial agents. © Springer-Verlag 2012.

Thang T.D.,Vinh University | Dai D.N.,Vietnam Academy of Science and Technology | Hoi T.M.,Vietnam Academy of Science and Technology | Ogunwande I.A.,Natural Products Research Unit
Natural Product Research | Year: 2013

The volatile compounds identified from four species of Annona from Vietnam are being reported. The oils were obtained from aliquots of plant samples by steam distillation and subjected to GC and GC-MS analysis. The main compounds of Annona glabra L., were β-caryophyllene (21.5%) germacrene D (17.7%), α-cadinol (5.4%) and β-elemene (5.2%). Annona squamosa L., comprised mainly of α-pinene (1.0-11.9%), limonene (0.8-11.7%), β-cubebene (0.5-13.0%), β-caryophyllene (11.6-24.5%), spathulenol (0.8-9.0%), caryophyllene oxide (1.0-10.6%) and α-cadinol (3.3-7.8%). The significant constituents of Annona muricata L., were α-pinene (9.4%), β-pinene (20.6%), ρ-mentha-2,4(8)-diene (9.8%), β-elemene (9.1%) and germacrene D (18.1%). However, camphene (0.2-6.6%), α-copaene (2.0-7.3%), β-elemene (5.9-16.6%), β-caryophyllene (8.3-14.9%), β-bisabolene (0.4-10.2%), δ-cadinene (1.7-4.8%) and germacrene D (9.3-22.8%) were the main compounds common to samples of Annona reticulata L. There were significant amounts of sabinene (11.2% and 2.7%; leaf and stem bark) and bicycloelemene (9.6% and 6.1%; stem and bark). © 2013 Taylor and Francis Group, LLC.

Dai D.N.,Vinh University | Thang T.D.,Vinh University | Ogunwande I.A.,Natural Products Research Unit
Natural Product Research | Year: 2014

This article reports the chemical components identified in the essential oil from the leaf and stem barks of Polyalthia harmandii (Pierre) Fin. and Gagnep., Polyalthia jucunda (Pierre) Fin. and Gagnep. and Polyalthia thorelii (Pierre) Fin. and Gagnep. The compounds identified in all the samples were -pinene (0.2-3.2%), myrcene (0.3-4.1%), (E)-β-ocimene (0.2-9.6%), bicycloelemene (0.2-18.0%), β-elemene (0.3-4.9%), β-caryophyllene (0.1-17.8%), germacrene D (4.4-20.1%), bicyclogermacrene (4.2-27.9%) and δ-cadinene (0.2-4.5%). Besides, benzyl benzoate (9.7%) and ishwarane (8.0%), respectively, were the other prominent compounds in the leaf and stem of P. harmandii. In addition, δ-3-carene (8.2%), -amorphene (6.5%), β-phellandrene (5.5%) and β-pinene (5.1%) were identified in P. jucunda leaf, while sabinene (30.9%) and β-phellandrene (10.2%) occurred largely in the stem. Moreover, γ-elemene (22.3% and 12.3%), germacrene D (10.5% and 6.9%) and spathulenol (9.1% and 11.8%) were identified in the leaf and stem of P. thorelii, while -terpinene (7.8%) and β-gurjunene (5.2%) were identified only in the leaf oil. © 2014 Taylor & Francis.

Suthiwong J.,Natural Products Research Unit | Pitchuanchom S.,Lampang Rajabhat University | Wattanawongdon W.,Liver Fluke and Cholangiocarcinoma Research Center | Hahnvajanawong C.,Liver Fluke and Cholangiocarcinoma Research Center | Yenjai C.,Natural Products Research Unit
Asian Journal of Chemistry | Year: 2014

Labdanes 1-4, stigmasterol (5) and vanillin (6) were isolated from the rhizomes of Curcuma petiolata. Compounds 2-4 exhibited strong to moderate cytotoxicity against cholangiocarcinoma cell lines. Compound 3 showed strong cytotoxicity with IC50 values ranging from 5-11 μg/mL. The molecular modeling was studied using the AutoDock 4 program. The docking results reveal that 3 interacted with EGFR through the 2 H-bond at Gln767 and Met769 with binding energy of -6.89 kcal/mol.

Yenjai C.,Natural Products Research Unit | Wanich S.,Natural Products Research Unit
Bioorganic and Medicinal Chemistry Letters | Year: 2010

Flavones 1-4 isolated from Kaempferia parviflora were used for structural modification. Sixteen flavonoid derivatives, including four new derivatives, were synthesized and evaluated for cytotoxicity against KB and NCI-H187 cell lines. Flavanones 2a-4a demonstrated higher cytotoxic activity than the parent compounds. Cytotoxicity against KB cell line of oxime 1c was about 7 times higher than the ellipticine standard. Interestingly, oximes 1c and 2c exhibited highly potent cytotoxicity against NCI-H187 cell line with IC50 values of 0.014 and 0.23 μM, respectively. Oximes 4c and 5c showed strong cytotoxicity against NCI-H187 cell line with IC50 values of 4.04 and 2.32 μM, respectively. © 2010 Elsevier Ltd. All rights reserved.

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