Polyhydroxybutyrates (PHBs) are macromolecules synthesized by bacteria. Because of their fast degradability under natural environmental conditions, PHBs were selected as alternatives for the production of biodegradable plastics. Sixteen PHB-accumulating strains were selected and compared for their ability to accumulate PHB granules inside their cells. Isolate AS-02 was isolated from cattle manure and identified as Bacillus wiedmannii AS-02 OK576278 by means of 16S rRNA analysis. It was found to be the best producer. The optimum pH, temperature, and incubation period for the best PHB production by the isolate were 7, 35 °C, and 72 h respectively. PHB production was the best with peptone and glucose as nitrogen and carbon sources at a C/N ratio of (2:1). The strain was able to accumulate 423, 390, 249, 158, and 144 mg/L PHB when pretreated orange, mango, banana, onion peels, and rice straw were used as carbon sources, respectively. The extracted polymer was characterized by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and GC-MS spectroscopy, which confirmed the structure of the polymer as PHB. The isolate B. wiedmannii AS-02 OK576278 can be considered an excellent candidate for industrial production of PHB from agricultural wastes.

Cloudy juices are attractive due to their nutritional and flavor features. However, cloudy juices usually suffer from the loss of important nutrients and from compromised quality and safety during processing and storage. In the current work, the influence of hydrocolloid flavor emulsion on the quality and safety of cloudy mango juice (CMJ) was first investigated. This emulsion was simply prepared by dissolving flavor vanillin (VA) in mango oil (MO) droplets followed by encapsulation with hydrocolloid gum Arabic (GA) and then homogenization using conventional method (GA‐VA/MO) and sonication (GA‐VA/MO‐S). The cloud stability, apparent viscosity, zeta‐potential (ζ), pH, total titratable acidity (TA), degree Brix, and antioxidant capacity tests were measured. The cloud stability of CMJs treated with GA‐VA/MO emulsion containing 3% and 5% (m/v) GA was significantly improved (p < .05) after 4 weeks of storage at 4°C