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The study was conducted at the Postharvest and plant Biotechnology laboratory, Department of Horticulture, Patuakhali Science and Technology University, Patuakhali, Bangladesh during the period from January to July 2017 to isolate, screening and molecular identification of antagonistic bacteria against anthracnose of mango. All treatments were arranged in a completely randomized design (CRD) with replications and repeated twice. Epiphytic bacteria, isolated from leaf and fruit surfaces of mango, were tested as biocontrol agent against anthracnose disease caused by Colletotrichum gloeosporioides wherein 20 strains were confirmed as antagonistic. Molecular characterization of the three potential strains of bacteria were done by the amplification of 16S rDNA gene following the extraction of genomic DNA, polymerase chain reaction (PCR) amplification, gel electrophoresis and gel documentation. The PCR amplified products and the genomic DNA samples were sent to the Macrogen Company through Sunchon National University, Seoul, South Korea for molecular identification by sequence analysis. Among the 20 antagonistic bacteria screened in vitro by dual and concomitant tests, two isolates, namely GB6 (PSTU-Hort-8), and GB19 (PSTU-Hort-14) were recognized as antagonistics to the test fungus. Using the molecular identification systems, isolated bacterial strains PSTU-Hort-8 was identified as B. subtilis with National Center for Biotechnology Information (NCBI) accession numbers MW659188; on the other hand, strain PSTU-Hort-14 was identified as Stenotrophomonas rhizophila with NCBI accession number MW659190.

The demand for healthy and ready-to-eat products has been growing steadily over the years. However, these products are very susceptible to spoilage and have a short shelf-life. In this research, edible coatings based on edible starch (aloe vera gel) and NaHCO3 were applied on fresh-cut vegetable samples (carrot and potato), and the changes in their bio-chemical properties and microbial changes were monitored during 6 days of storage at 4ºC. Two factor experiments, Factor A; postharvest treatments (different concentration of aloe gel and NaHCO3) and Factor B; two vegetable species (Carrot and Potato) were laid out in a Completely Randomized Design (CRD) with three replications. Different concentration of aloe vera gel and NaHCO3 solutions were prepared as per treatment. The prepared slices of vegetable species were treated with different treatment combinations and stored in 200 g capacity polyethylene bags sealed under air, vacuum or modified active atmosphere and then bio-chemically (Titratable Acidity (TA), Ascorbic Acid (AA) content, Total Soluble Solids (TSS), Reducing Sugar (RS), Non-reducing Sugar (NRS), pH) and microbiologically assessed. Higher rate of edible starch (30%) + NaHCO3 (2%) treated potato (CT12) showed the superior performance on TA (1.290), TSS (5.200% Brix), NRS content (0.340) and pH (4.773% Brix) compare to control and other interaction treatments of the study at 6 days after storage while  untreated potato (T0) showed statistically lower AA (6.575 mg/25 g) TA (0.464) TSS (3.856), pH (3.827) NRS (0.133). Growth of bacterial colonies on NA media had statistically highest (14.00) in untreated potato and lowest (5.00) in T12 treated potato while fungal colonies on PDA media range of 4.00 to 11 at 6 DAS. The study may help small-scale establishments to increase the shelf-life of minimally processed vegetables.