Bernard Owaga

Prof. Bernard Owaga

University of KwaZulu-Natal, Pietermaritzburg. South Africa
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Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2014 in Polyhedron
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Journal Article
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DADivambal Appavoo
Divambal Appavoo
Bernard OwagaBernard Owaga
Bernard Owaga
IGIlia A. Guzei
Ilia A. Guzei
JWJuanita van Wyk
Juanita van Wyk
OZOrpah Zinyemba
Orpah Zinyemba
JDJames Darkwa
James Darkwa

24 February 2021 in Molecules
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Journal Article
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Adesola AdelekeAdesola Adeleke
Adesola Adeleke
SZSizwe Zamisa
Sizwe Zamisa
Shahidul IslamShahidul Islam
Shahidul Islam
KOKolawole Ayodapo Olofinsan
Kolawole Ayodapo Olofinsan
VSVeronica Salau
Veronica Salau
Bernard OwagaBernard Owaga
Bernard Owaga
A series of fifteen silver (I) quinoline complexes Q1–Q15 have been synthesized and studied for their biological activities. Q1–Q15 were synthesized from the reactions of quinolinyl Schiff base derivatives L1–L5 (obtained by condensing 2-quinolinecarboxaldehyde with various aniline derivatives) with AgNO3, AgClO4 and AgCF3SO3. Q1–Q15 were characterized by various spectroscopic techniques and the structures of [Ag(L1)2]NO3Q1, [Ag(L1)2]ClO4Q6, [Ag(L2)2]ClO4Q7, [Ag(L2)2]CF3SO3Q12 and [Ag(L4)2]CF3SO3Q14 were unequivocally determined by single crystal X-ray diffraction analysis. In vitro antimicrobial tests against Gram-positive and Gram-negative bacteria revealed the influence of structure and anion on the complexes′ moderate to excellent antibacterial activity. In vitro antioxidant activities of the complexes showed their good radical scavenging activity in ferric reducing antioxidant power (FRAP). Complexes with the fluorine substituent or the thiophene or benzothiazole moieties are more potent with IC50 between 0.95 and 2.22 mg/mL than the standard used, ascorbic acid (2.68 mg/mL). The compounds showed a strong binding affinity with calf thymus-DNA via an intercalation mode and protein through a static quenching mechanism. Cytotoxicity activity was examined against three carcinoma cell lines (HELA, MDA-MB231, and SHSY5Y). [Ag(L2)2]ClO4Q7 with a benzothiazole moiety and [Ag(L4)2]ClO4Q9 with a methyl substituent had excellent cytotoxicity against HELA cells.

1 May 2016 in Journal of Molecular Catalysis A: Chemical
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Journal Article
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JGJoel Mwangi Gichumbi
Joel Mwangi Gichumbi
HFHolger B. Friedrich
Holger B. Friedrich
Bernard OwagaBernard Owaga
Bernard Owaga

1 February 2014 in Journal of Molecular Catalysis A: Chemical
Verified
Journal Article
Closed access
COCollins Obuah
Collins Obuah
Bernard OwagaBernard Owaga
Bernard Owaga
KNKyoko Nozaki
Kyoko Nozaki
JDJames Darkwa
James Darkwa

2 March 2020 in Applied Organometallic Chemistry
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Journal Article
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SOSegun Daniel Oladipo
Segun Daniel Oladipo
Bernard OwagaBernard Owaga
Bernard Owaga
CMChunderika Mocktar
Chunderika Mocktar