Chemical and Biological Technologies in Agriculture最新文献

This study aimed to investigate the effects of fermentation on the physicochemical properties and in vitro antioxidant activities of Glycyrrhiza leaf, compare the structures of unfermented (GLP) and fermented (FGLP) polysaccharides, and assess their growth-promoting and antioxidant activities using zebrafish embryos. The results showed that the polysaccharide content, extract yield, and reduced sugar content of Glycyrrhiza leaf increased significantly after 36 h of fermentation. In parallel, in vitro antioxidant activities assays demonstrated that Glycyrrhiza leaf fermented for 36 h exhibited strong DPPH, hydroxyl radical scavenging, and reducing power. Scanning electron microscope and infrared spectroscopy analyses revealed differences in the surface morphology of unfermented and fermented Glycyrrhiza leaf, with both polysaccharides being acidic and containing pyranose rings and α-glycosidic bonds. The molecular weight of FGLP was lower than that of GLP, and the molar ratios of guluronic acid, amino glucose, glucuronic acid, glucose, xylose, and arabinose were increased. In the zebrafish model, Glycyrrhiza leaf polysaccharides promoted the growth and development of zebrafish embryos, with the most pronounced effect at a concentration of 20 µg/mL after fermentation. FGLP exhibited superior protective effects against lipid peroxidation and cell death induced by 2,2′-azobis (2-methylpropionamidine) dihydrochloride. The findings demonstrated that fermentation could enhance the utilization of Glycyrrhiza leaf polysaccharides and their antioxidant capacity. These findings opened avenues for further research into the bioavailability of FGLP in vivo and offered valuable insights into its potential as a natural and innovative antioxidant.

Highlights

• Variations on physicochemical parameters and antioxidant activity were tracked during fermentation.

• Fermentation should last for 36 h based on the dynamic changes.

• The molecular weight of polysaccharides decreased after fermentation.

• FGLP has growth-promoting and developmental effects on zebrafish.

• FGLP exhibited superior protective effects against lipid peroxidation and cell death induced by AAPH.

Graphical Abstract

Background

Fishpond sediments (FPS) are rich in organic carbon and nutrients, making them valuable as fertilizers and soil conditioners. Stabilizing heavy metals like chromium (Cr), copper (Cu), and zinc (Zn) is essential to reduce their bioavailability and risks. This study evaluates zinc oxide (ZnO) and silicon (Si) nanoparticles synthesized from Azolla pinnata and Equisetum arvense for heavy metal immobilization and nutrient enhancement in FPS from San Jiang (SJ) and Tan Niu (TN), China.

Methods

Nanoparticles were synthesized using Azolla pinnata and Equisetum arvense. Fishpond sediments from San Jiang (SJ) and Tan Niu (TN) were treated with ZnO and Si nanoparticles. Heavy metals and nutrients were analyzed via ICP-OES and soil analysis, while sequential extraction assessed metal distribution in geochemical fractions.

Results

The application of these nanoparticles, especially the green-synthesized zinc oxide nanoparticles (GSZnONPs), was found to significantly reduce the concentrations of chromium (Cr), copper (Cu), and zinc (Zn) in both the overlying and pore water of the FPS. This reduction not only minimizes the leachability of these heavy metals, but also substantially decreases their bioavailability. The study recorded a notable shift in the acid-soluble metal fraction, resulting in an average reduction of Cr concentrations by 31–28%, Cu by 18–21%, and Zn by 32–23% in the sediments from San Jiang (SJ) and Tan Niu (TN). Moreover, the application of these nanoparticles also improved the nutrient profile of the sediments, potentially enhancing their utility as fertilizers.

Conclusion

Zinc oxide and silicon nanoparticles synthesized from Azolla pinnata and Equisetum arvense are effective in immobilizing heavy metals in fishpond sediments, significantly reducing their bioavailability and potential environmental risks. The use of these green-synthesized nanoparticles not only mitigates heavy metal contamination, but also enhances the nutrient content of the sediments, making them more suitable for use as soil conditioners and fertilizers. This dual benefit highlights the potential of these nanoparticles as a sustainable solution for managing contaminated fishpond sediments while contributing to agricultural productivity.

Graphical Abstract

Background

Sucrose phosphate synthase (SPS) is an important enzyme in the sucrose synthesis of plants, governing the accumulation and distribution of photosynthetic assimilates, which is essential for plant growth and stress tolerance.

Results

This study successfully identified eight NtSPS genes within the genome of cultivated tobacco. Phylogenetic analysis revealed that these genes are categorized into three subfamilies, a classification supported by the examination of their gene structures and conserved domains. The promoters of the NtSPSs contained a variety of cis-elements associated with plant development, responses to phytohormones, and stress resistance. Expression profiling demonstrated that NtSPS genes exhibit distinct expression patterns across different tissues and under various stress conditions. Notably, the majority of NtSPS genes, especially NtSPS5 and NtSPS6, showed high expression in leaves and increased expression in both roots and leaves following drought treatment. Furthermore, overexpression of NtSPS5 and NtSPS6 in tobacco plants significantly improved the germination rate under mannitol treatment and enhanced the activity of antioxidant enzymes along with chlorophyll fluorescence parameters under drought stress. These results suggest that NtSPS5 and NtSPS6 have a positive impact on drought stress tolerance in tobacco plants.

Conclusions

Therefore, this study provides the significant target in drought resistance breeding and lays the foundation for further investigation into the function and regulatory mechanisms of SPS genes.

Graphical Abstract

Background

DnaJA proteins, a prominent subfamily of the DnaJ family, function as molecular chaperones that respond to various external stresses. Extensive studies on the DnaJ family have been conducted in plants. However, research on this subfamily in tobacco remains relatively scarce.

Results

In this study, we identified 24 DnaJA genes in tobacco, and classified them into three individual groups. A comprehensive analysis based on gene structure, motif composition, and evolutionary pattern revealed the divergence of tobacco DnaJA genes. For the evolution of the NtDnaJA genes, purification selection was the major factor. In addition, the potential regulatory network unveiled that NtDnaJAs could be regulated by miRNAs and various transcription factors associated with diverse stress responses. Through expression pattern analysis of public RNA-seq datasets and qRT-PCR experiments, it was observed that many NtDnaJAs displayed tissue-specific expression and might play significant roles in different biotic and abiotic stresses. Additionally, the pivotal role of NtDnaJA3 in boosting plant drought resistance was confirmed.

Conclusions

This study provides important perspectives on the evolution of NtDnaJA genes and their involvement in stress responses, laying the groundwork for future research into the roles of DnaJA regulatory genes in tobacco.

Graphical Abstract

The growing concerns over food safety have intensified calls for alternatives to toxic pesticides in agriculture. Despite these concerns, the global agricultural industry remains heavily reliant on chemical pesticides to maintain crop yields. However, the overuse of these chemicals has resulted in significant biodiversity loss and environmental degradation, highlighting the urgent need for safer, non-toxic, and sustainable alternatives. Trichloroisocyanuric acid (TCCA), a cost-effective and relatively safe industrial oxidant commonly used for disinfection, has shown potential for plant disease management. However, its application in this context remains largely unexplored. In this study, we evaluate the efficacy of TCCA in controlling Pseudomonas syringae pv. actinidiae (Psa), the causative agent of bacterial canker in kiwifruit, and explore its underlying mechanisms of action. Our results demonstrate that TCCA effectively inhibits Psa growth in vitro, even at low concentrations, with minimum inhibitory concentrations (MICs) of 20 mg/L (TCCA added directly to the Psa suspension) and 100 mg/L (Psa cells mixed with liquid LB medium before adding TCC). In vivo, TCCA treatment at a concentration of 500 mg/L substantially reduced Psa colonization on both kiwifruit leaves and canes, outperforming conventional bactericides such as copper hydroxide, chlorothalonil, and ethylicin, as well as alternative treatments like pyraclostrobin-dysonline and Xinjunan acetate. Mechanistic investigations revealed that TCCA inhibited bacterial biofilm formation, impaired motility, disrupted cell integrity, and suppressed the expression of virulence-related genes, ultimately leading to bacterial cell death. Additionally, TCCA treatment of both healthy and infected canes induced the activity of key defense-related enzymes, including catalase (CAT), peroxidase (POD), glutathione reductase (GR), and phenylalanine ammonia-lyase (PAL), suggesting that TCCA may activate systemic plant defense responses. These findings position TCCA as a promising, environmentally friendly alternative to traditional toxic bactericides, offering a sustainable and effective solution for plant disease management with reduced ecological risks.

Graphical Abstract

Sparassis latifolia is a rare edible mushroom with many pharmacological activities. Active screening found that the crude polysaccharide from this mushroom (SLP) exhibited noticeable gastroprotective effects. However, it remains unclear regarding the underlying regulatory mechanism of the gastroprotective effects of SLP. A novel polysaccharide SLP-2 was purified from the fruiting bodies of S. latifolia, and characterized using FT-IR, HPAEC, SEM, SEC–MALLS-RI, methylation, and NMR analysis. Structural characterization revealed that the backbone of SLP-2 was mainly composed of → 4)-α-D-Glcp-(1 → , → 3)-α-D-Glcp-(1 → and → 3,4)-α-D-Glcp-(1 → . The branched chain primarily consisted of β-D-Glcp-(1 → linked to the sugar residue → 3, 6)-β-D-Glcp-(1 → at the O-6 position and → 3,4)-β-D-Glcp-(1 → at the O-4 position. Physiological experimental results demonstrated that SLP-2 effectively protected GES-1 cells against ethanol-induced damage by suppressing intracellular ROS levels and cell apoptosis while elevating the activities of SOD and CAT enzymes. Furthermore, transcriptome analysis revealed molecular mechanisms underlying the gastroprotective effect of SLP-2, with KEGG enrichment suggesting associations with ferroptosis, TNF, PI3K–Akt, MAPK and IL-17 signaling pathways. These findings provide a technological foundation for valuable utilization of S. latifolia and emphasize the potential application of SLP-2 in repairing gastric mucosal injuries.

Graphical Abstract

Soil organic carbon (OC) sequestration in farmlands can be improved through fertilizer applications, particularly with the addition of organic amendments. However, our knowledge of the effects of long-term different fertilization on OC chemical stability and carbon management index (CMI), as well as their response to crop productivity remains limited in rice–rice cropping system. The objectives of this study were to investigate the effects of fertilization on various OC sequestration indicators in bulk soil and chemical fractions, and establish their relationships with crop productivity. The treatments selected in the present study were those which had undergone long-term fertilization under double-rice cropping including: (1) no fertilization (CK); (2) combined application of chemical nitrogen, phosphorous, and potassium fertilizers (NPK); (3) the doubled rate of NPK treatment (2NPK); and (4) NPK treatment plus organic fertilizers (NPKM). After 29 years of fertilization, we observed that NPKM resulted in the highest OC stocks (11.47 and 26.15 Mg ha⁻¹, respectively) and distribution ratios (24 and 54%, respectively) in the less-labile fraction and passive pool. Conversely, it showed the lowest OC values in the labile fraction and active pool compared to CK, NPK, and 2NPK treatments. Additionally, NPKM significantly (P < 0.05) increased CMI (by 47 and 33%) over CK and NPK treatments, which suggests that soil receiving NPKM was better managed. Apart from maintaining higher crop yields and increasing OC input, NPKM also tremendously enhanced OC sequestration as indicated by the highest soil OC stock (48.80 Mg ha⁻¹) and OC sequestration rate (CSR, 0.37 Mg ha⁻¹ yr⁻¹). There was an increasing trend of CSR and passive OC pool, but a decreasing trend of carbon sequestration efficiency with increasing OC input, which may be associated with OC saturation behavior of soil. Furthermore, crop yield showed significant positive linear correlations with passive OC pool and CMI. In summary, long-term combined application of chemical and organic fertilizers enhanced OC sequestration and crop productivity by improving passive OC pool and CMI, which contributed to realize agricultural sustainability in double-cropping rice regions.

Graphical Abstract

Background

One of the main concerns for ecological sustainability is finding ways to convert byproducts from medicinal aroma plants into high-value ingredients. The Damask rose (Rosa damascena Mill.) is a valuable species of aromatic rose that is grown in specific floriculture regions of Iran for the extraction of essential oils or preparation of rose water. The rose is widely used in cosmetics, flavor or fragrance formulations, and pharmaceutical products worldwide. The process of water-steam distillation is commonly used to extract rose oil, with an extraction efficiency of ~ 0.03–0.05% for active components. However, a significant amount of waste is generated during this process, with a large portion of the distillate being composed of water. This waste is known as rose oil hydrodistillation wastewater (RODW) and is considered a biocontaminant. It poses major ecological difficulties when disposed of in surface water and public drainage systems, due to the high concentration of complex degradable chemical compounds, such as polyphenols.

Results

This study highlights the potential of using three different types of microorganisms, namely Lactobacillus acidophilus, Pichia pastoris, and Saccharomyces cerevisiae for the conversion of glycosidically conjugated forms of nonvolatile aroma precursors into valuable aroma compounds. Gas chromatography-mass spectrometry (GC–MS) analysis demonstrated that all three microorganisms could affect the concentration of volatile components. However, when the sample was treated with S. cerevisiae for 120 h, the highest levels of recovery were observed for phenyl ethyl alcohol and eucalyptol, which were 2.5 and 80 times greater than those of the untreated sample, respectively. Moreover, the levels of α-pinene and anethole were also increased to ~ 9.7 and 11.7 times after 48 h of treatment, respectively. Additionally, the fermentation process increased in the total phenolic and flavonoid contents.

Conclusion

Using different microbial biocatalysts to recover natural bioactive aroma compounds is an attractive and scalable bioconversion methodology for producing value-added chemical derivatives from the waste of medicinal plants.

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Sea buckthorn leaves (Hippophae rhamnoides L.) (SBL) are considered a promising new source of antioxidants. The process of enzymatic hydrolysis facilitates the breakdown of plant cell walls, promoting the release of polysaccharides. In this study, we optimized the enzymatic hydrolysis process of SBL to enhance the release of polysaccharides, resulting in enzymatically hydrolyzed SBL polysaccharides (ESBLP), and compared the differences in composition and physicochemical properties between SBL polysaccharides (SBLP) and ESBLP. The antioxidant activity of both SBLP and ESBLP was assessed using DPPH and hydroxyl radical assays in vitro. In addition, their protective effects against AAPH-induced oxidative stress were evaluated in zebrafish embryos. The results indicated that using pectinase with an enzyme dosage of 4500 U/g, at a temperature of 50 °C, a material-to-liquid ratio of 1:1, and a reaction time of 48 h, the polysaccharides content after enzymatic hydrolysis increased from 84.51 to 224.93 mg/g, representing a 179.34% increase. Compared to SBLP, ESBLP exhibited enhanced solubility, oil-holding capacity, and higher L (brightness), a* (redness), and b* (yellowness) values. ESBLP also showed a lower molecular weight and higher protein content. Morphologically, the dense sheet-like structure of SBLP transformed into a fragmented porous surface in ESBLP, with notable changes in monosaccharide composition. In vitro experiments demonstrated that ESBLP had a stronger scavenging ability against DPPH and hydroxyl radicals. In an oxidative stress model using zebrafish, ESBLP significantly reduced the production of reactive oxygen species (ROS) and lipid peroxidation levels. In conclusion, the ESBLP we prepared not only showed increased polysaccharides content and improved physicochemical properties but also exhibited superior antioxidant activity. These findings provide valuable insights for the further development and utilization of SBL.

Graphical Abstract