The suitability of a given protein for use in food products depends heavily on characteristics such as foaming capacity, emulsifiability, and solubility, all of which are affected by the protein structure. Notably, protein structure, and thus characteristics related to food applications, can be altered by treatment with high-power ultrasound (HUS). Almonds are a promising source of high-quality vegetable protein for food products, but their physicochemical and functional properties remain largely unexplored, limiting their current applications in foods. Here, we tested the use of HUS on almond protein isolate (API) to determine the effects of this treatment on API functional properties. Aqueous almond protein suspensions were sonicated at varying power levels (200, 400, or 600 W) for two durations (15 or 30 min). The molecular structure, protein microstructure, solubility, and emulsifying and foaming properties of the resulting samples were then measured. The results showed that HUS treatment did not break API covalent bonds, but there were notable changes in the secondary protein structure composition, with the treated proteins showing a decrease in α-helices and β-turns, and an increase in random coil structures as the result of protein unfolding. HUS treatment also increased the number of surface free sulfhydryl groups and decreased the intrinsic fluorescence intensity, indicating that the treatment also led to alterations in the tertiary protein structures. The particle size in aqueous suspensions was decreased in treated samples, indicating that HUS caused the dissociation of API aggregates. Finally, treated samples showed increased water solubility, emulsifying activity, emulsifying stability, foaming capacity, and foaming stability. This study demonstrated that HUS altered key physicochemical characteristics of API, improving critical functional properties including solubility and foaming and emulsifying capacities. This study also validated HUS as a safe and environmentally responsible tool for enhancing desirable functional characteristics of almond proteins, promoting their use in the food industry as a high-quality plant-based protein.

Biochar fertilization improves soil fertility and carbon sequestration, implying agricultural and environmental advantages. The effect of different sized previously applied biochar and biofertilizer agents on succeeding crops remains poorly known for legume–cereal cropping cycles. This study compared different particle-sized biochar and biofertilizer strains applied to lentils for their residual impact on subsequent maize growth, nutrition, and soil fertility without further polluting the environment. Three particle sizes (<2, 2–5, 5–10 mm) of Babul tree (Acacia arabica) wood biochar was obtained through grinding and sieving and applied prior to the lentil (first) crop at a rate of 500 g m⁻². The commercial Rhizobium leguminosarum products Biozote-N and Rhizogold were inoculated to lentil seeds before sowing. The effect of biochar and biofertilizer agents on the succeeding maize (second) crops was evaluated for soil and crop performance. Findings revealed that particle sizes of <2 mm biochar and Biozote-N inoculation enhanced plant height, leaf area and leaf area index, biological yield, and thousand grain weight of the subsequent maize crop. Maize grain yield was enhanced by 2.5%, tissue N uptake by 15%, nitrogen uptake efficiency by 17%, grain protein content by 15%, extractable P by 17%, and soil bulk density by 3% with a residual biochar particle size of <2 mm and Biozote-N inoculation. It was concluded that the finely grounded (<2 mm) biochar particle combined with inoculation of Biozote-N was superior to larger particle sizes for enhancing crop growth and improving soil fertility status at the residual level, benefiting the subsequent crop in a legume–cereal rotation system.

Salicylic acid (SA) plays a crucial role in alleviating drought stress in plants. However, little is known about the molecular mechanisms underlying exogenous SA on the drought tolerance of kenaf. In this study, the kenaf seedlings were subjected to physiological and transcriptomic analysis under control (CK), moderate drought stress (D), and moderate drought stress with 1 mM SA (D_SA). Under drought conditions, SA significantly improved the plant biomass, leaf area, antioxidant enzyme activities (SOD, POD, and CAT), soluble sugars, starch and proline contents, and photosynthesis, while the contents of MDA, H₂O₂, and O₂⁻ were significantly decreased. A total of 3430 (1118 up-regulated and 2312 down-regulated) genes were differentially expressed in group D, compared with group CK. At the same time, 92 (56 up-regulated and 36 down-regulated) genes were differentially expressed in group D_SA compared with group D. GO and KEGG analysis showed that the differentially expressed genes (DEGs) were enriched in various metabolic pathways, such as carbohydrate metabolism, lipid metabolism, and the metabolism of terpenoids and polyketides. Results showed that the genes related to the antioxidant system, sucrose and starch synthesis, osmoregulation, ABA signal regulation, and differentially expressed transcription factors, such as AP2/ERF4 and NF-Y1, were involved in the increased drought tolerance of kenaf under exogenous SA. Virus-induced gene silencing (VIGS)-mediated silencing of salicylate binding protein 2 gene (HcSABP2) decreased the drought resistance of kenaf seedlings. Thus, the present study provides valuable insights into the regulatory mechanism of exogenous SA in alleviating drought stress in kenaf.

Agave hybrid cultivar 11,648 has been planted for sisal fiber production in China since the 1960s. However, little is known about the population structure and genetic diversity of agave germplasms in China. Therefore, we developed a group of core SNP markers to evaluate the population structure and genetic diversity of 125 agave germplasms in China, including 20 cultivars, 14 breeding lines, and 89 transplanted resources from different areas. Cost-effective amplicon sequencing technology was used to identify genetic variants. The results grouped most cultivars and breeding lines together, which indicated that local agave breeding programs aimed to improve fiber and disease-resistance traits. These breeding programs have reduced genetic diversity, even with the gene flows from other Agave species. The neighbor-joining phylogenetic tree revealed the relationships between A. H11648 and its parents. The phylogenetic relationship between A. sisalana and A. amanuensis is doubtful, even if they are considered heterotypic synonyms. The 11 agave germplasms introduced from Mexico suggest the abundant diversity of agave germplasms in Mexico, which is also the source of agave germplasms in China. This study provides a sketch map for agave germplasms in China, which will benefit future studies related to population genetics and breeding works of agave.

Returning agricultural waste/by-products to the field is an effective management measure to improve soil fertility and maintain crop productivity in agroecosystems. However, we still have limited understanding of the complex response of sisal (Agave sisalana Perrine) growth, soil nutrients and microbial communities to the long-term sisal residue return to the ecological system. This study aimed to investigate the comprehensive effects of returning sisal residue to the field on sisal yield, soil nutrient, and microbial community. Based on a four-year field experiment, the results showed that returning sisal residue to the field increased the annual yield of sisal by 30.77–33.36%. Compared with control group, sisal residue inputs significantly improved soil total nitrogen, available phosphorus, and available potassium by 46.59, 3.02, and 1.21%, respectively. Under sisal residue input condition, the activities of soil catalase, urease, acid phosphatase, and sucrase also significantly increased by 2.01, 17.20, 17.40 and 16.60%, respectively. A higher ratio of bacteria/fungi was observed in the soil amended with sisal residue. The microbial diversity analysis showed that the α-diversity of the bacterial community increased, while the α-diversity of the fungal community decreased with the sisal residue treatment. However, sisal residue return had a higher impact on the α-diversity of fungi. This study provides evidence that returning sisal residue to the field affects sisal productivity by regulating nutrient cycling and soil microbial community. Moreover, the study suggests that microbial α-diversity has significant influence on sisal yield.