The physico-chemical and antioxidant activity of the mesocarp and exocarp of Borassus flabellifer were determined to assess the potential of the fruit as a food ingredient. Proximate analysis indicated that both mesocarp and exocarp had a high fibre content of 23.92% and 28.20%, respectively, of which 62.5% and 79.4% were insoluble dietary fibre. The soluble dietary fibre was < 0.50% for both samples. Hemicellulose was the major component in the exocarp followed by cellulose and lignin. Meanwhile for the mesocarp, cellulose was the highest component followed by hemicellulose and lignin. Fructose, galactose, glucose, mannose and sucrose were detected in both samples. Phenol and tannins were present in both mesocarp and exocarp; however, saponin was only detected in the mesocarp. Radical scavenging activity (157.05 mM TE/g) and reducing power (213.05 mM Fe2+) of the exocarp were significantly higher as compared to those of the mesocarp.
Ten solvents were used to extract phytochemicals from the peel of Carica papaya cv.
Sekaki/Hong Kong to determine their antibacterial activities. Moderate to clear inhibition on
Corynebacterium diphtheriae, Streptococcus pneumoniae, Bacillus subtilis and Clostridium
perfringens were obtained from the disk diffusion test out of fourteen pathogens tested.
Petroleum ether extract, the most potent extract, showed moderate inhibition towards C.
diphtheriae and S. pneumoniae at MIC of 5.63 mg/mL and 1.40 mg/mL. Polar solvents
gave higher yield, total phenolic and total flavonoid contents than nonpolar solvents. Extract
yields were 10.9 to 84.1 mg/g in polar solvents and 3.9 to 20.3 mg/g in non-polar solvents.
Twenty eight compounds were identified in petroleum extracts through GC/MS analysis.
Among the compounds identified were fatty acids, esters, alkane, tocopherols and sterols.
9,12,15-octadecatrienoic acid was the most abundant compound.
The effects of flow rate, different pressures and temperatures on cocoa butter extracted from cocoa nib using supercritical carbon dioxide (scCO2) were investigated. The yield was analyzed for total fat content, triacylglycerol (TG) profile, and fatty acid (FA) profile. Extractions were carried out at pressures of 20 and 35 MPa, temperatures of 50 and 60 °C, and CO2 flow rates of 0.5, 1, 2, 4 mL min(-1). The result shows that the yield of cocoa butter extract increased with increasing pressure, temperature, and flow rate and the optimum conditions for the maximum cocoa butter extraction were 35 MPa, 60 °C and 2 mL min(-1), repectively. TGs and FAs were found to be similar in composition to those of cocoa butter obtained by conventional methods. The lower molecular weight TGs and FAs showed higher selectivity compared to higher molecular weight TGs and FAs.
The physicochemical properties of κ-carrageenan films extracted from Eucheuma cottonii (E. cottonii) incorporated with different concentrations and types of plasticizers were studied. Glycerol, sorbitol, and polyethylene glycol-300 (PEG-300) in the range of 10-60% were used as plasticizers. The results showed that the thickness and moisture content (MC) of films increased significantly (p≤0.05) with the increase in plasticizer concentration. Sorbitol-plasticized films had the lowest values. Sorbitol-plasticized films have better mechanical properties and the lowest water vapor permeability (WVP), solubility and water uptake ratio (WUR) compared with glycerol and PEG-plasticized films (p≤0.05). Fourier transform infrared (FTIR) spectra showed the intermolecular reactions between κ-carrageenan and the plasticizers in the films. Scanning electron microscopy (SEM) observations indicated that sorbitol-plasticized films have a compact structure, even at the highest concentration. The melting temperature (Tm) of films decreased (p≤0.05) with an increase in the plasticizer concentration. Here, the glycerol-plasticized films had the lowest values. X-ray diffraction (XRD) showed broad and narrow peaks of the un-plasticized κ-carrageenan film at 2θ=20.0° and 2θ=8.4°, respectively. The intensity of the broad peak increased and the narrow peak disappeared as the concentration of plasticizers increased. In conclusion, films from E. cottonii successfully produced with sorbitol as the plasticizer exhibited good physical properties as packaging films.