Nam Weng Sit

Dr. Nam Weng Sit

Department of Allied Health Sciences, Universiti Tunku Abdul Rahman, Kampar, Malaysia
orcid

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

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

Representative Publications

View All Publications
1 October 2000 in Clinical Pharmacokinetics
Verified
Journal Article
Closed access
PDF file
VNVisweswaran Navaratnam
Visweswaran Navaratnam
SMSharif Mahsufi Mansor
Sharif Mahsufi Mansor
NSNam Weng Sit
Nam Weng Sit
JGJames Grace
James Grace
QLQigui Li
Qigui Li
POPiero Olliaro
Piero Olliaro

5 December 2020 in Antibiotics
Verified
Journal Article
Open access
PDF file
Wen-Jie NgWen-Jie Ng
Wen-Jie Ng
NSNam Weng Sit
Nam Weng Sit
POPeter Aun-Chuan Ooi
Peter Aun-Chuan Ooi
KEKah Yaw Ee
Kah Yaw Ee
TLTuck-Meng Lim
Tuck-Meng Lim
Scientific studies about the antibacterial effects of honeydew honey produced by the stingless bee are very limited. In this study, the antibacterial activities of 46 blossom and honeydew honeys produced by both honey bees and stingless bees were evaluated and compared. All bacterial isolates showed varying degrees of susceptibility to blossom and honeydew honeys produced by the honey bee (Apis cerana) and stingless bee (Heterotrigona itama and Geniotrigona thoracica) in agar-well diffusion. All stingless bee honeys managed to inhibit all the isolates but only four out of 23 honey bee honeys achieved that. In comparison with Staphylococcus aureus, Escherichia coli was found to be more susceptible to the antibacterial effects of honey. Bactericidal effects of stingless bee honeys on E. coli were determined with the measurement of endotoxins released due to cell lysis. Based on the outcomes, the greatest antibacterial effects were observed in honeydew honey produced by H. itama. Scanning electron microscopic images revealed the morphological alteration and destruction of E. coli due to the action of this honey. The combination of this honey with antibiotics showed synergistic inhibitory effects on E. coli clinical isolates. This study revealed that honeydew honey produced by H. itama stingless bee has promising antibacterial activity against pathogenic bacteria, including antibiotic resistant strains.

1 June 2023 in Insects
Verified
Journal Article
Open access
PDF file
HLHuimei Lim
Huimei Lim
SLSook Yee Lee
Sook Yee Lee
LHLai Yee Alicia Ho
Lai Yee Alicia Ho
NSNam Weng Sit
Nam Weng Sit
Despite ongoing control efforts, the mosquito population and diseases vectored by them continue to thrive worldwide, causing major health concerns. There has been growing interest in the use of botanicals as alternatives to insecticides due to their widespread insecticidal properties, biodegradability, and adaptability to ecological conditions. In this study, we investigated the larvicidal activity and cytotoxicity effects of solvent extracts from three aromatic plants—Curcuma longa (turmeric), Ocimum americanum (hoary basil), and Petroselinum crispum (parsley)—against Aedes albopictus. Subsequently, we examined the phytochemical composition of the extracts through gas chromatography–mass spectrometry (GC–MS) analysis. Results revealed that the hexane extracts of O. americanum and P. crispum exhibited the greatest larvicidal activity with the lowest median lethal concentration (LC50) values (<30 µg/mL) at 24 h post-treatment, with the former found to be significantly less toxic towards African monkey kidney (Vero) cells. The GC–MS analysis of the said extract indicated the presence of different classes of metabolites, including phenylpropanoids, very long-chain alkanes, fatty acids and their derivatives, and terpenes, with the most abundant component being methyl eugenol (55.28%), most of which, have been documented for their larvicidal activities. These findings provide valuable insights into the potential use and development of bioinsecticides, particularly from O. americanum.

16 December 2021 in Molecules
Verified
Journal Article
Open access
PDF file
Wen-Jie NgWen-Jie Ng
Wen-Jie Ng
NSNam Weng Sit
Nam Weng Sit
POPeter Aun-Chuan Ooi
Peter Aun-Chuan Ooi
KEKah Yaw Ee
Kah Yaw Ee
TLTuck-Meng Lim
Tuck-Meng Lim
Stingless bee honey, specifically honeydew honey, is generally valued for its better health benefits than those of most blossom types. However, scientific studies about the differentiation of stingless bee honey based on honeydew and blossom origins are very limited. In this study, 13C NMR spectroscopy was employed to quantify the seven major sugar tautomers in stingless bee honey samples, and the major sugar compositions of both honeydew and blossom types were found not significantly different. However, several physicochemical properties of honeydew honey including moisture content, free acidity, electrical conductivity, ash content, acetic acid, diastase, hydrogen peroxide, and mineral elements levels were significantly higher; while total soluble solid, proline, and hydroxymethylfurfural were significantly lower than blossom honey. Greater antioxidant capacity in honeydew honey was proven with higher total phenolic compounds, ABTS, DPPH, superoxide radical scavenging activities, peroxyl radical inhibition, iron chelation, and ferric reducing power. Using principal component analysis (PCA), two clusters of stingless bee honey from the honeydew and blossom origin were observed. PCA also revealed that the differentiation between honeydew and blossom origin of stingless bee honey is possible with certain physicochemical and antioxidant parameters. The combination of NMR spectroscopy and chemometrics are suggested to be useful to determine the authenticity and botanical origin of stingless bee honey.

8 November 2015 in Tropical Journal of Pharmaceutical Research
Verified
Journal Article
Open access
PDF file
SCSze Mun Chan
Sze Mun Chan
KKKong Soo Khoo
Kong Soo Khoo
NSNam Weng Sit
Nam Weng Sit
Interactions between Plant Extracts and Cell Viability Indicators during Cytotoxicity Testing: Implications for Ethnopharmacological Studies

1 September 2018 in Journal of Medical Mycology
Verified
Journal Article
Closed access
NSNam Weng Sit
Nam Weng Sit
YCY.S. Chan
Y.S. Chan
SLS.C. Lai
S.C. Lai
LLL.N. Lim
L.N. Lim
GLG.T. Looi
G.T. Looi
HOH.C. Ong
H.C. Ong