Biosurfactants are becoming an important alternative to chemical surfactants in almost every sector in the modern industry because of their improved properties compared to their chemical counterparts. The aim of this study is to isolate and identify bacterial strain from different environment conditions with the capacity to produce rhamnolipid-biosurfactants when grown on blue agar plate (BAP) selective medium. Five strains were screened out using the combination of modified drop-collapse test, oil spreading and emulsification index (E24) test. A strain with an outstanding performance and demonstrated good activity in all the above screening methods was successfully isolated and had shown comparable results against Triton-X 100, a chemical surfactant. The emulsifying capacity of this strain was evaluated by the emulsification index (E24) and it ranged from 54.7% - 62.1%. Using the morphological and BiologGen III MicroPlate analysis, the strain was identified as Pseudomonas aeruginosa. In this study, an efficient and simple protocol to screen out rhamnolipid-biosurfactants producing bacteria was used and this finding will also help to add novel members to the biosurfactants group as well as expanded its current knowledge regarding the diversity and productive capability biosurfactants from a single specific strain. Therefore, this strain might be useful as an alternative to chemical surfactants for a wide range of potential applications.

The effects of honey-spices marination on simultaneous formation of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs) in gas-grilled beef satay were investigated at different grilling temperatures (150 °C, 250 °C, and 350 °C). Beef satay samples used in this study were prepared using two types of honey-spices marination (Apis mellifera-spices and Trigona sp.-spices). Quantifications of fifteen PAHs using high performance liquid chromatography with fluorescence detection (HPLC-FLD) and nine HCAs using liquid chromatography tandem-mass spectrometry (LC-MS/MS) were performed with gradient programme. Results on PAHs and HCAs in marinated samples were compared with

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The peel and core discarded from the processing of MD2 pineapple have the potential to be valorized. This study evaluated the functional and volatile compounds in the extracts of MD pineapple peel and core (MD2-PPC). The total soluble solids, pH, titratable acidity, sweetness index, and astringency index were 9.34 °Brix, 4.00, 0.74%, 12.84, and 0.08, respectively, for the peel and 12.00 °Brix, 3.96, 0.32%, 37.66, and 0.03, respectively, for the core. The fat and protein contents of the peel and core were found to be significantly different (p < 0.05). The total phenolic (TPC) and flavonoid contents (TFC) were significantly higher in the peel. The peel also showed better antioxidant activity, with a half-maximal inhibitory concentration (IC50) of 0.63 mg/mL for DPPH free radical activity compared with the core. The TPC of different phenolic fractions from peel extract was highest in the glycosylated fraction, followed by the esterified, insoluble-bound, and free phenolic fractions. GC–MS analysis identified 38 compounds in the peel and 23 in the core. The primary volatile compounds were 2-furan carboxaldehyde, 5-(hydroxymethyl), and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP). The identification of phenolics and volatile compounds provides important insights into the valorization of (MD2-PPC) waste.