Project description:The rapid postharvest deterioration of fresh fruits is closely associated with fungal contamination,particularly by Aspergills niger, which severely compromises storage stability and market value.In this study, a fruit endophytic strain, Bacillus velezensis LY G-26, was isolated and shown toproduce volatile organic compounds (VOCs) with strong antifungal activity. VOCs significantlyinhibited 4. niger mycelial growth, spore gemination, and sporulation, and induced severemembrane disruption and mitochondrial damage. HS-SPME-GC-MS/MS identified 2-nonanone,2,S-dimethylpyrazine, and trans-2,3-dimethylacrylic acid as the primary active VOCs, with2-nonanone exhibiting the strongest inhibition. To enable practical application in food systems,LYG-26 was encapsulated into superabsorbent polymer beads, creating a packaging-compatibleslow-release system. When incorporated into sealed storage containers, the beads continuouslyreleased VOCs and significantly reduced A. niger decay in longan, effectively extending theirpostharvest shelf life. These findings provide a safe and environmentally friendly strategy forpostharvest preservation and shelf-life enhancement.
Project description:H. seropedicae is a diazotrophic and endophytic bacterium that associates with economically important grasses promoting plant growth and increasing productivity. To identify genes related to bacterial ability to colonize and promote plant growth wheat seedlings growing hydroponically in Hoaglandâs medium were inoculated with H. seropedicae the bacteria and incubated for 3 days. mRNA from the bacteria present in the root surface and in the plant medium were purified, depleted from rRNA and used for RNA-seq profiling. RT-qPCR analyses were conducted to confirm regulation of selected genes. Comparison of RNA profile of bacteria attached to the root and planktonic revealed an extensive metabolic adaptation to the epiphytic life style.