Phenotypic Characterization and Identification of Potential L-Asparaginase-Producing Thermohalophilic Bacteria from Wawolesea Hot Spring, North Konawe, Southeast Sulawesi, Indonesia.

<b>Background and Objective:</b> L-asparaginase-producing thermohalophilic bacteria have the potential of producing an enzyme tolerant to high heat and salt levels. This enzyme, L-asparaginase, can be used as a biological agent for the cancer therapy of acute lymphoblastic leukemia and melanosarcoma as it has a specific ability to inhibit the formation of nutrients for cancer cells. This enzyme is also used effectively in food industries operating at high temperatures due to its ability to reduce acrylamide, a trigger of cancer cells. This study sought to figure out the phenotypic characters of and identify potential L-asparaginase-producing thermohalophilic bacteria from Wawolesea Hot Spring, North Konawe, Southeast Sulawesi. <b>Materials and Methods:</b> The characterization conducted on potential L-asparaginase-producing thermohalophilic bacterial isolates consisted of the following: Colony morphological characterization, covering the shapes, edges, internal structures, elevations and colours of the colonies, cell morphological characterization, covering gram staining, endospore formation and motility, biochemical characterization, covering catalase, Methyl Red and Voges Proskauer (MR-VP), gelatin hydrolysis, citrate, indole and carbohydrate fermentation tests and physiological characterization, covering pH effect, salinity, oxygen demand and temperature effect tests. Bacterial isolate identification was carried out in two stages, namely phenetic identification based on the phenotypic characterization data determine through a preliminary identification and numeric-phenetic identification. <b>Results:</b> The characterization results showed that the bacterial isolates AAT 1.4, AAT 3.2 and CAT 3.4 were <i>bacillus</i>-shaped, Gram-positive, motile, catalase-positive and aerobic. Based on the numeric-phenetic analysis results, the isolates AAT 1.4 and CAT 3.4 had a 92.9% similarity to <i>Bacillus subtilis</i>, while isolate AAT 3.2 had a 92.9% similarity to <i>Brevibacillus limnophilus</i>. <b>Conclusion:</b> According to the numeric-phenetic analysis results, the isolates AAT 1.4 and CAT 3.4 belong to the species <i>Bacillus subtilis</i>, while isolate AAT 3.2 belongs to the species <i>Brevibacillus limnophilus</i>.

Properties and Application of Edible Modified Bacterial Cellulose Film Based Sago Liquid Waste as Food Packaging.

Bacterial cellulose (BC) based on sago liquid waste has been developed to be used as food packaging. This study investigated the physicochemical and mechanical properties of modified BC film and its application as food packaging. The modified BC film performed carboxymethyl cellulose (CMC) as a stabilizer and glycerol as a plasticizer. Films were prepared by casting technique using BC as the primary material and composites with various concentrations of CMC and glycerol (0.5%, 1%, and 1.5%, v/v). BC film was applied as the packaging of meat sausage, and the quality of meat sausage was measured based on weight loss, moisture content, pH, protein content, and total microbial count. The addition of CMC and glycerol influences the physical and mechanical properties of BC composites film. The best mechanical properties of edible BC film were collected by adding 1% CMC and 1% glycerol with a tensile strength of 17.47 MPa, elongation at a break of 25.60%, and Young's modulus of 6.54 GPa. FTIR analysis showed the characteristic bands of BC, and the addition of CMC and glycerol slightly changed the FTIR spectrum of the composites. The utilization of modified BC-based sago liquid waste film as the packaging of meat sausage could maintain sausage quality during 6 days of storage at room temperature. Therefore, edible BC film has the potential to be used as food packaging.