Isovaleramide

This study investigated the impact of drying process on the flavor profiles of the economically significant Pyropia haitanensis and Neopyropia yezoensis, aiming to clarify how species differences and drying process influence volatile and non-volatile flavor compounds. Using GC × GC-TOFMS and LC-MS, the volatile metabolites, free amino acids (FAAs), and nucleotides were analyzed. A total of 2774 volatile components, including 76 odor-active compounds (OACs), were identified, with aldehydes, ketones, benzenoids, and pyrazines as dominant contributors. The key volatiles responsible for their unique flavor were 2-nonenal, 2-octenal, heptanal, 2-pentylfuran, and 1-octen-3-one. Fresh P. haitanensis exhibited a superior flavor profile due to higher OACs and umami compounds, while high-temperature drying significantly enhanced the umami and sweet flavor notes in N. yezoensis by increasing aromatic volatiles and umami FAAs. These findings demonstrate that species differences and processing methods significantly influence laver flavor, providing valuable insights for improving product quality.

Plant-associated microbiome plays important role in maintaining overall health of the host plant. Xanthium strumarium displaying resilience to various environmental fluctuations may harbor some bacterial isolates which can help this plant to grow worldwide. The present study aims to isolate endophytic and rhizospheric bacteria from X. strumarium and assess their plant growth-promoting and Ralstonia solanacearum antagonism activity. From a total of 148 isolated bacteria, 7 endophytic and 2 rhizospheric bacterial isolates were found to endow with significant in vitro plant growth promotion activities. The 16S rRNA gene sequence similarity of the 7 endophytic isolates has revealed these bacteria belonging to 5 genera viz. Curtobacterium, Pantoea, Pseudomonas, Microbacterium and Paracoccus whereas, the two rhizospheric isolates were identified as species of Ralstonia pickettii and Priestia megaterium. Maximum growth promotion was observed using the strains Pseudomonas fluorescens XSS6 and Microbacterium hydrothermale XSS20 in the assay conducted on tomato plants. In the in planta inhibition assay of R. solanacearum carried out in tomato seedlings using root bacterization method, Pseudomonas fluorescens XSS6 and Panotea vagans XSS3 showed antagonistic activity with biocontrol efficacy of 94.83% and 83.96%, respectively. GC-MS analysis detected several known antimicrobial compounds in the extract of the culture supernatant of Pseudomonas fluorescens XSS6 and Panotea vagans XSS3 strains, which may contribute to the inhibition of R. solanacearum by these strains. The results of our study indicated that the bacteria associated with X. strumarium exhibit multiple plant-beneficial effects. These bacteria have the potential to be developed as effective biofertilizers and biological control agents, promoting sustainable agriculture practices.