Chemical Profiling and Biological Activities of Stingless Bee Honey and Propolis from the Selected Areas in Sarawak

• Main Author: Easter Sirah, Kelabo
• Format: Thesis
• Language: English; English
• Published: - 2022
• Subjects: QD Chemistry
• Online Access: http://ir.unimas.my/id/eprint/38431/5/Easter%20Sirah%20-%20cutted.pdf; http://ir.unimas.my/id/eprint/38431/9/Easter%20Sirah%20fulltext.pdf; http://ir.unimas.my/id/eprint/38431/

Stingless bees products such as honey and propolis have been widely studied due to their profound therapeutic properties. The increase in commercial values of stingless bee products has made it susceptible to adulteration practices, such as the addition of either natural or scientific sweeteners into stingless bee honey. This study was conducted to analyse stingless bee honey and propolis from Serapi Garden, Siniawan Farm, and PoliKu Farm and their chemical constituents. The chemical composition of stingless bee honey and propolis were then compared with the extracts of predominant flowers from the respective locations. The glucose content, heavy metals-environmental contaminants, and biological activities of stingless bee honey and propolis were also analysed for the authenticity and quality determination of the stingless bee products. Analysis of chemical constituents was conducted using gas chromatography-mass spectrometer (GC-MS). The analysis depicted various chemical components in honey and propolis, which interestingly correlated with the chemical composition of the predominant flowering at the respective locations. Glucose content in honey analysed by using high-performance liquid chromatography (HPLC) showed low glucose content (61.19 – 174.53 g/L), while heavy metals content for environmental contaminants analysis conducted using inductively coupled plasma-optical emission spectroscopy (ICP-OES) showed the predominant elements Zn (0.069 – 1.653 ppm) that is below the permissible limit. The 1H Nuclear Magnetic Resonance (1H-NMR) spectra obtained from the honey samples depicted strong fatty alcohols signals present at 3.5 – 4.5 ppm, which can be used as potential chemical biomarkers. The presence of phenolic, aliphatic acids and fatty alcohols in the honey and propolis has contributed to the excellent antibacterial activities against Escherichia coli (MIC = 144; inhibition zone = 19mm) and Staphylococcus aureus (MIC = 170; inhibition zone = 9mm). The antioxidant activities of honey and propolis showed excellent antioxidant properties with IC50 values of 5.068 and 4.083 ppm, respectively. These results indicated that stingless bee honey and propolis in Sarawak possessed unique chemical composition that can be used as potential biomarkers, antimicrobial and antioxidant agents.