HS-GC-IMS detection of volatile organic compounds in Acacia honey powders under vacuum belt drying at different temperatures.

Honey is a commodity of great nutritional value, but deep-processed honey products are uncommon. Herein, we used vacuum belt dryer to dry Acacia honey at 60°C, 70°C, and 80°C, prepared it into powder, and analyzed its volatile compound differences. We established HS-GC-IMS method to detect the volatile organic compounds (VOCs) of these three Acacia honey powders (AHPs). In total, 77 peaks were detected, and 23 volatile compounds were identified, including eight aldehydes, six ketones, three furans, one alcohol, one phenol, one lactone, one ester, one acid, and one nitrile. Moreover, principal component analysis (PCA) and fingerprint similarity analysis based on the Euclidean distance distinguished the three heating temperature treatments. Clearly, it was concluded that there are significant differences in volatile substances at different tested temperatures, and when the AHP was incubated at 80°C, more volatile compounds were detected.

[Cloning and functional analysis of the cotton Trihelix transcription factor GhGT29].

Trihelix transcription factors are important proteins involved in response to abiotic stresses in plants. Understanding the molecular mechanisms of Trihelix in cottons will lay the foundation to improve stress tolerance by gene engineering. In this study, a gene encoding Trihelix transcription factor was isolated in upland cottons using reverse transcription PCR according to bioinformatic analysis. The gene was named as GhGT29 (GenBank accession No. JQ013097), which was 1 092 bp, contained a 1 089 bp open reading frame and encoded a protein of 363 amino acids with a predicted molecular weight of 40.9 kDa and a isoelectric point of 5.45. SMART analysis showed GhGT29 contained one typical SANT motif. Phylogenetic analysis showed that GhGT29 belonged to the SH4 subfamily of the Trihelix family and was most closely related to AtSH4-like1 and AtSH4-like2. Quantitative real-time PCR (qRT-PCR) analysis revealed that GhGT29 was induced by high salt, drought, cold and abscisic acid. The expression profile also revealed that GhGT29 was constitutively expressed in all tested tissues, such as roots, stems, leaves, flowers, ovules (0 DPA) and fibers (12 DPA). The expression level of GhGT29 was the highest in flowers and the lowest in stems. Using the Arabidopsis protoplasts assay system, we found that the GhGT29 protein was located in cell nuclei and had trans-activation activity. These results revealed that GhGT29 might be involved in the regulation of stress resistance-related genes in stress signaling pathways in upland cottons.