The encapsulation of essential oils in edible films is a feasible approach for fruit packaging. However, the precise release of essential oils from the films has not yet been achieved. In this study, an edible composite film with pH-responsive release was prepared by the formation of Schiff-base imine bonds between chitosan (CS) and oxidized fucoidan (CS–FU) and encapsulating cinnamaldehyde (CA). Fourier-transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed the formation of Schiff-base imine bonds between the amino group of CS and the aldehyde group of oxidized FU; therefore, the CA/CS–FU composite film exhibited good pH-responsive release and antibacterial properties under mild acidic environments. Owing to the encapsulation of CA, CA/CS–FU composite films exhibited superior opacity, water vapor barrier, mechanical properties, and antibacterial properties compared to CS and CS–FU films. CA/CS–FU composite films with 0.1 g of CA can maintain the freshness and appearance of litchi at least eight days longer than CS and CS–FU films. Hence, multifunctional composite films are prospective eco-friendly and intelligently responsive controlled-release packaging materials for fruit preservation.
This study investigated the effects of exogenous nitric oxide (NO) on growth, antioxidant enzymes, and key nitrogen metabolism enzymes in pepper seedlings under high-temperature stress. In addition, targeted metabolomics was used to study the differential accumulation of amino acid metabolites, thereby providing theoretical support for the use of exogenous substances to mitigate high-temperature stress damage in plants. The results showed that high-temperature stress increased soluble sugar, soluble protein, amino acids, proline, malondialdehyde (MDA), and hydrogen peroxide (H2O2) content, electrolyte leakage, and superoxide anion (O2·-) production rate while altering the activities of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX)] and key nitrogen metabolism enzymes [nitrate reductase (NR), glutamine synthetase (GS), glutamate dehydrogenase (GDH), and nitric oxide synthase (NOS)]. c-PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide, an NO scavenger) exacerbates oxidative stress and further reduces NO content and enzyme activities. However, exogenous SNP (sodium nitroprusside, an NO donor) effectively alleviated these adverse effects by enhancing antioxidant defense mechanisms, increasing NO content, and normalizing amino acid metabolite levels (kynurenine, N-acetyl-L-tyrosine, L-methionine, urea, and creatine), thereby maintaining normal plant growth. These findings suggest that SNP can enhance stress tolerance in pepper seedlings by improving osmotic regulation, antioxidant capacity, and nitrogen metabolism, effectively mitigating the damage caused by high-temperature stress.
We assessed SLC27A1, a candidate gene for milk production traits in Chinese Holstein cattle. DNA was extracted from the blood of 48 top Chinese Holstein Cattle selected according to phenotypic character and mixed into DNA pool for SNP detection. We tested blood samples of these cattle for SNPs in exon 3 and the 3'-flanking region of the SLC27A1 gene by using polymerase chain reaction-single-stranded conformation polymorphism (PCR-SSCP) and DNA sequencing. We found 2 polymorphic sites: 112T>C, a synonymous mutation, in exon 3 (SNP(1)), and 64G>A in the 3'-UTR (SNP(2)). We also determined the genotypes of 330 Chinese Holstein cattle by using PCR-restriction fragment length polymorphism (RFLP). We found 3 genotypes each at SNP(1) (TT, TC, and CC) and SNP(2) (GG, GA, and AA). The association among the different genotypes at these 2 sites and milk production traits was analyzed using a least-squares procedure. The results showed that cows with genotype CC had higher milk yields than those with genotype TC (0.01 < p < 0.05). No significant difference was detected among the 3 SNP(2) genotypes in terms of milk production traits. Our results provide evidence that the C allele have potential effects on milk yield trait.
The random amplified polymorphic DNA(RAPD) technique was used to analyze the genetic diversity and phylogenetic relationship of 4 varieties of Psidium guajava.7 primers which had good repeat and clear bands were screened from 50 arbitrary 10-mer primers.The total 49 bands were obtained and these bands all displayed polymorphism.49 RAPD bands were recorded and the obtained characters data were used to calculate genetic distances.The cluster analysis was conducted by using PAUP*4.0b10 software with the unweighted pair-group method of arithmetic averages(UPGMA).The results showed there were genetic diversities with genetic distances from 0.154 74 to 0.451 61 among 4 varieties of Psidium guajava and they can be classified into two groups.
Eucalyptus leaf blight, caused by Calonectria spp., significantly impacts the global Eucalyptus industry. Calonectria dianii, as one of the predominant causal agents, poses a serious threat to Eucalyptus plantations in China. To enhance our understanding of its pathogenic mechanisms, we sequenced the genome of C. dianii RIFT 6520 using both Nanopore PromethION and Illumina NovaSeq PE150 platforms. Our analysis revealed a 61.76 Mb genome comprising 30 contigs with an N50 of 4,726,631 bp, a GC content of 49.74 %, and 10,184 predicted coding genes. Additionally, comparative genomic analysis between C. dianii and seven other significant plant-pathogenic Calonectria species was conducted. This analysis provided insights into the evolutionary relationships and adaptive mechanisms of these pathogens. Our study elucidates the genetic basis of C. dianii's pathogenicity and evolution, providing valuable information for future research on its molecular interactions with Eucalyptus and aiding in the development of precise control measures for Eucalyptus leaf blight.
3-Dehydroquinate dehydratase/shikimate dehydrogenase (DQD/SDH) is a key rate-limiting enzyme that catalyzes the synthesis of the shikimate, which is an important metabolic intermediate in plants and animals. However, the function of SlDQD/SDH family genes in tomato (Solanum lycopersicum) fruit metabolites is still unknown. In the present study, we identified a ripening-associated SlDQD/SDH member, SlDQD/SDH2, that plays a key role in shikimate and flavonoid metabolism. Overexpression of this gene resulted in an increased content of shikimate and flavonoids, while knockout of this gene by CRISPR/Cas9 mediated gene editing led to a significantly lower content of shikimate and flavonoids by downregulation of flavonoid biosynthesis-related genes. Moreover, we showed that SlDQD/SDH2 confers resistance against Botrytis cinerea attack in post-harvest tomato fruit. Dual-luciferase reporter and EMSA assays indicated that SlDQD/SDH2 is a direct target of the key ripening regulator SlTAGL1. In general, this study provided a new insight into the biosynthesis of flavonoid and B. cinerea resistance in fruit tomatoes.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)