Transcriptome analysis reveals how cadmium promotes root development and accumulates in Apocynum venetum, a promising plant for greening cadmium-contaminated soil.

Cadmium (Cd) contamination poses a substantial threat the environment, necessitating effective remediation strategies. Phytoremediation emerges as a cost-efficient and eco-friendly approach for reducing Cd levels in the soil. In this study, the suitability of A. venetum for ameliorating Cd-contaminated soils was evaluated. Mild Cd stress promoted seedling and root growth, with the root being identified as the primary tissue for Cd accumulation. The Cd content of roots ranged from 0.35 to 0.55 mg/g under treatment with 10-50 µM CdCl2·2.5 H2O, and the bioaccumulation factor ranged from 28.78 to 84.43. Transcriptome sequencing revealed 20,292 unigenes, and 7507 nonredundant differentially expressed genes (DEGs) were identified across five comparison groups. DEGs belonging to the "MAPK signaling pathway-plant," "monoterpenoid biosynthesis," and "flavonoid biosynthesis pathway" exhibited higher expression levels in roots compared to stems and leaves. In addition, cytokinin-related DEGs, ROS scavenger genes, such as P450, glutathione-S-transferase (GST), and superoxide dismutase (SOD), and the cell wall biosynthesis-related genes, CSLG and D-GRL, were also upregulated in the root tissue, suggesting that Cd promotes root development. Conversely, certain ABC transporter genes, (e.g, NRAMP5), and some vacuolar iron transporters, predominantly expressed in the roots, displayed a strong correlation with Cd content, revealing the mechanism underlying the compartmentalized storage of Cd in the roots. KEGG enrichment analysis of DEGs showed that the pathways associated with the biosynthesis of flavonoids, lignin, and some terpenoids were significantly enriched in the roots under Cd stress, underscoring the pivotal role of these pathways in Cd detoxification. Our study suggests A. venetum as a potential Cd-contaminated phytoremediation plant and provides insights into the molecular-level mechanisms of root development promotion and accumulation mechanism in response to Cd stress.

Co-application of chitooligosaccharides and arbuscular mycorrhiza fungi reduced greenhouse gas fluxes in saline soil by improving the rhizosphere microecology of soybean.

Soil salinization can affect the ecological environment of soil and alter greenhouse gas (GHG) emissions. Chitooligosaccharides and Arbuscular mycorrhizal fungi (AMF) reduced the GHG fluxes of salinized soil, and this reduction was attributed to an alteration in the rhizosphere microecology, including changes in the activities of ß-glucosidase, acid phosphatase, N-acetyl-ß-D-glucosidase, and Leucine aminopeptidase. Additionally, certain bacteria species such as paracoccus, ensifer, microvirga, and paracyclodium were highly correlated with GHG emissions. Another interesting finding is that foliar spraying of chitooligosaccharides could transport to the soybean root system, and improve soybean tolerance to salt stress. This is achieved by enhancing the activities of antioxidant enzymes, and the changes in amino acid metabolism, lipid metabolism, and membrane transport. Importantly, the Co-application of chitooligosaccharides and Arbuscular mycorrhiza fungi was found to have a greater effect compared to their application alone.

In vitro and in vivo activities of eugenol against tobacco black shank caused by Phytophthora nicotianae.

Phytophthora nicotianae causes serious black shank disease in tobacco. Syringa oblata essential oil and its main components were evaluated to develop an effective and environmentally friendly biocontrol agent. Eugenol, which exhibited the strongest activity, was intensively investigated in vitro and in vivo. The mycelial growth of P. nicotianae was inhibited by eugenol at a minimum inhibitory concentration of 200µgmL-1, and inhibition occurred in a dose-dependent manner. Extracellular pH and extracellular conductivity results indicated that eugenol increased membrane permeability. Flow cytometry and fluorescent staining results further showed that eugenol disrupted mycelial membranes but did not affect spore membrane integrity. The in vivo results confirmed that treatment of tobacco with various concentrations of eugenol formulations reduced disease incidence and better controlled against the disease. Our results suggested that the ability of eugenol to control tobacco black shank depended on its ability to damage mycelial membranes and that eugenol formulations have potential as an eco-friendly antifungal agent for controlling tobacco blank shank.

Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method.

Ultrasonic-assisted extraction (UAE) was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM), based on a four-factor, five-level central composite design (CCD), was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined by using 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) methods. The results showed good fit with the proposed models for the total flavonoid extraction (R² = 0.9849), for the antioxidant extraction assayed by ABTS method (R² = 0.9764), and by DPPH method (R² = 0.9806). Optimized extraction conditions for total flavonoids was a ratio of liquid to solid of 57.16 mL/g, 62.33 °C, 57.08 min, and 52.14% ethanol. The optimal extraction parameters of extracts for the highest antioxidant activity by DPPH method was a ratio of liquid to solid 60.3 mL/g, 54.56 °C, 45.59 min, and 46.67% ethanol, and by ABTS assay was a ratio of liquid to solid 47.29 mL/g, 63.73 °C, 51.62 min, and 60% ethanol concentration. Our work offers optimal extraction conditions for total flavonoids and antioxidants from alfalfa.

A glucomannan produced by Bacillus velezensis HY23 and its growth promoting effect on soybeans under salt stress.

The Bacillus genus is widely distributed in nature, has bacteriostatic and growth-promoting activities, and has broad application potential in agriculture. An exopolysaccharide (EPS) was extracted and purified from Bacillus velezensis HY23. Structural characterisation of the EPS was performed by chemical and spectroscopic analyses. Methylation analysis showed that the EPS of HY23 was composed of mannose and glucose at a ratio of 82:18 and was identified as glucomannan. Combined with the nuclear magnetic resonance (NMR) analysis, EPS from HY23 had a backbone of →2)-α-D-Manp-(1 â†’ and →2,6)-α-D-Manp-(1 â†’ branched at C-6 with terminal α-(3-O-Me)-D-Manp-(1 â†’ and →6)-α-D-Manp-(1 â†’ residues as the side chain. A certain amount of ß-D-Glcp residues were also present in backbone. Moreover, EPS significantly improved the nitrogen-fixing activity and salt resistance of soybean seedlings by regulating the antioxidant pool and expression of ion transporters. These findings indicate that EPS from B. velezensis HY23 is a potential biostimulant for enhancing plant resistance to salt stress.

A Smart Pesticide-Controlled Release Platform with Dual Stimuli-Responsive Functions for Enhanced Treatment of Plant Black Shank.

Realizing controllable input of botanical pesticides is conducive to improving pesticide utilization, reducing pesticide residues, and avoiding environmental pollution but is extremely challenging. Herein, we constructed a smart pesticide-controlled release platform (namely, SCRP) for enhanced treatment of tobacco black shank based on encapsulating honokiol (HON) with mesoporous hollow structured silica nanospheres covered with pectin and chitosan oligosaccharide (COS). The SCRP has a loading capacity of 12.64% for HON and could effectively protect HON from photolysis. Owing to the pH- and pectinase-sensitive property of the pectin, the SCRP could smartly release HON in response to a low pH or a rich pectinase environment in the black shank-affected area. Consequently, the SCRP effectively inhibits the infection of P. nicotianae on tobacco with a controlled rate for tobacco black shank of up to 87.50%, which is mainly due to the SCRP's capability in accumulating ROS, changing cell membrane permeability, and affecting energy metabolism. In addition, SCRP is biocompatible, and the COS layer enables SCRP to show a significant growth-promoting effect on tobacco. These results indicate that the development of a stimuli-responsive controlled pesticide release system for plant disease control is of great potential and value for practical agriculture production.

Chitooligosaccharides and Arbuscular Mycorrhizal fungi alleviate the damage by Phytophthora nicotianae to tobacco seedlings by inducing changes in rhizosphere microecology.

Arbuscular mycorrhizal fungi (AMF) and Chitooligosaccharide (COS) can increase the resistance of plants to disease. COS can also promote the symbiosis between AMF and plants. However, the effects of AMF & COS combined application on the rhizosphere soil microbial community of tobacco and the improvement of tobacco's resistance to black shank disease are poorly understood.·We treated tobacco with AMF, COS, and combined application of AMF & COS (AC), respectively. Then studied the incidence, physio-biochemical changes, root exudates, and soil microbial diversity of tobacco seedling that was inoculated with Phytophthora nicotianae. The antioxidant enzyme activity and root vigor of tobacco showed a regular of AC > AMF > COS > CK, while the severity of tobacco disease showed the opposite regular. AMF and COS enhance the resistance to black shank disease by enhancing root vigor, and antioxidant capacity, and inducing changes in the rhizosphere microecology of tobacco. We have identified key root exudates and critical soil microorganisms that can inhibit the growth of P. nicotianae. The presence of caprylic acid in root exudates and Bacillus (WdhR-2) in rhizosphere soil microorganisms is the key factor that inhibits P. nicotianae growth. AC can significantly increase the content of caprylic acid in tobacco root exudates compared to AMF and COS. Both AMF and COS can significantly increase the abundance of Bacillus in tobacco rhizosphere soil, but the abundance of Bacillus in AC is significantly higher than that in AMF and COS. This indicates that the combined application of AMF and COS is more effective than their individual use. These findings suggest that exogenous stimuli can induce changes in plant root exudates, regulate plant rhizosphere microbial community, and then inhibit the growth of pathogens, thereby improving plant resistance to diseases.

Ulva prolifera polysaccharide enhances the root colonisation by Bacillus amyloliquefaciens strain Cas02.

The application of biocontrol agent is important for the sustainable development of agriculture. Unsuccessful or limited colonisation by plant growth-promoting rhizobacteria (PGPR) has become an important constraint factor for their commercial application. Here, we report that Ulva prolifera polysaccharide (UPP) promotes root colonisation by Bacillus amyloliquefaciens strain Cas02. UPP serves as an environmental signal for bacterial biofilm formation and its glucose residue is used as a carbon source for the synthesis of the exopolysaccharides and poly-gamma-glutamate present in biofilm matrix. Greenhouse experiments demonstrated that UPP could effectively enhance the root colonisation by Cas02 in both the bacterial population and survival time under natural semiarid soil conditions. Furthermore, the microbiome analysis also indicated the promoted colonisation by Cas02, as well as the improved bacterial rhizosphere community structure, after combined treatment of UPP and Cas02. This study provides a practical approach to improve the biocontrol agent with seaweed polysaccharides.

Extraction of honokiol from Artemisia argyi and in vitro and in vivo investigation of its antifungal activity.

Extracts from plants used in Chinese medicine can be good sources of fungicides for agricultural applications. In this study, we separated and identified antifungal compounds from four traditional Chinese medicine extracts and evaluated their antifungal activities in vitro and in vivo. In vitro, honokiol extracted from Artemisia argyi showed broad-spectrum antimicrobial and mycelial inhibitory activity with EC50 in the range 3.56 - 33.85 µg/mL against eight plant pathogens. q-PCR indicated that honokiol might induce cell cancerisation and inhibit cellular respiration, which provided significant insights into honokiol function in tobacco resistance to molecular mechanisms of the phytopathogenic fungus Phytophthora nicotianae. In vivo, honokiol significantly decreased the rate of fungal infection in eggplants, potatoes, grapes, cherry tomatoes, and cucumbers, and enhanced disease resistance in tobacco. Overall, our results indicate that honokiol has the potential to control a variety of fungal and oomycete diseases, and A. argyi could be a source of honokiol.

AMF colonization affects allelopathic effects of Zea mays L. root exudates and community structure of rhizosphere bacteria.

Arbuscular mycorrhizal fungi (AMF) widely exist in the soil ecosystem. It has been confirmed that AMF can affect the root exudates of the host, but the chain reaction effect of changes in the root exudates has not been reported much. The change of soil microorganisms and soil enzyme vigor is a direct response to the change in the soil environment. Root exudates are an important carbon source for soil microorganisms. AMF colonization affects root exudates, which is bound to have a certain impact on soil microorganisms. This manuscript measured and analyzed the changes in root exudates and allelopathic effects of root exudates of maize after AMF colonization, as well as the enzymatic vigor and bacterial diversity of maize rhizosphere soil. The results showed that after AMF colonization, the contents of 35 compounds in maize root exudates were significantly different. The root exudates of maize can inhibit the seed germination and seedling growth of recipient plants, and AMF colonization can alleviate this situation. After AMF colonization, the comprehensive allelopathy indexes of maize root exudates on the growth of radish, cucumber, lettuce, pepper, and ryegrass seedlings decreased by 60.99%, 70.19%, 80.83%, 36.26% and 57.15% respectively. The root exudates of maize inhibited the growth of the mycelia of the pathogens of soil-borne diseases, and AMF colonization can strengthen this situation. After AMF colonization, the activities of dehydrogenase, sucrase, cellulase, polyphenol oxidase and neutral protein in maize rhizosphere soil increased significantly, while the bacterial diversity decreased but the bacterial abundance increased. This research can provide a theoretical basis for AMF to improve the stubble of maize and the intercropping mode between maize and other plants, and can also provide a reference for AMF to prevent soil-borne diseases in maize.

Investigation of the growth performance, blood status, gut microbiome and metabolites of rabbit fed with low-nicotine tobacco.

Tobacco contains a large amount of bioactive ingredients which can be used as source of feed. The objective of this study was to evaluate the effects of dietary addition of low-nicotine tobacco (LNT) on the growth performance, blood status, cecum microbiota and metabolite composition of meat rabbits. A total of 80 Kangda meat rabbits of similar weight were assigned randomly as four groups, and three of them were supplemented with 5%, 10%, and 20% LNT, respectively, with the other one fed with basal diet as control group. Each experiment group with 20 rabbits was raised in a single cage. The experiments lasted for 40 days with a predictive period of 7 days. The results revealed that LNT supplementation had no significant effect on the growth performance, but increased the half carcass weight compared with control group. Dietary supplemention of LNT decreased the triglycerides and cholesterol content in rabbit serum, and significantly increased the plasma concentration of lymphocytes (LYM), monocytes, eosinophils, hemoglobin HGB and red blood cells. In addition, LNT supplementation significantly changed the microbial diversity and richness, and metagenomic analysis showed that LNT supplementation significantly increased Eubacterium_siraeum_group, Alistipes, Monoglobus and Marvinbryantia at genus level. Moreover, LC-MS data analysis identified a total of 308 metabolites that markedly differed after LNT addition, with 190 significantly upregulated metabolites and 118 significantly downregulated metabolites. Furthermore, the correlation analysis showed that there was a significant correlation between the microbial difference and the rabbit growth performance. Overall, these findings provide theoretical basis and data support for the application of LNT in rabbits.

Comparison of Phenolic and Flavonoid Compound Profiles and Antioxidant and α-Glucosidase Inhibition Properties of Cultivated Soybean (Glycine max) and Wild Soybean (Glycine soja).

Wild soybean (Glycine soja Sieb.et Zucc; WS) has been used as a traditional food in China for many years and contains significantly higher levels of isoflavones than cultivated soybean (Glycine max; CS), but the secondary metabolites, including flavonoids and the phenolic composition differences between them, remain unclear. The results showed that WS possessed significantly higher total phenolic and flavonoid content and exhibited better antioxidant and α-glucosidase inhibition activities as well as excellent protective effects against H2O2-induced oxidative injury in a human endothelial cell line. Through metabolomic analysis, 642 metabolites were identified, and 238 showed differential expression, with 151 upregulated and 87 downregulated. A total of 79 flavonoid compounds were identified, 42 of which were upregulated in WS. 2'-Hydroxygenistein, garbanzol, protocatechuic aldehyde, ligustilide, and resveratrol were the most discriminated compounds in WS. The metabolic pathway analysis of differential metabolites related to the biosynthesis of flavonoids and phenolic acids were the biosynthesis of phenylpropanoids, flavonoids, isoflavonoids, flavones, and flavonols. This study substantially elucidated differences in the content of flavonoids and biological activities between WS and CS, which is useful information for the effective utilization of these two black soybean species in food processing.

Purification and characterization of a fucoidan from the brown algae Macrocystis pyrifera and the activity of enhancing salt-stress tolerance of wheat seedlings.

A fuciodan (Mw = 11.1 kDa) was obtained and purified from Macrocystis pyrifera (MPF). MPF was an acid heteropolysaccharide including fucose, mannose, xylose, galactose, rhamnose, glucuronic acid, and glucose in a molar ratio of 3.1:1.0:0.86:0.63:0.25:0.33:0.11. Sulfate content in MPF was 28.6%, and the molar ratio of fucose to sulfate (Fuc:SO42-) was 1.0:0.58. The structure of MPF was mainly consist of repeating →3)-ß-L-Fucp (2SO3-)-(1→ and →4)-ß-D-Xylp-(1→3)-ß-L-Fucp(2SO3-)-(1→ and with α-L-Fucp-(1→ and →6)-α-D-Galp-(1→ in branches. Moreover, the effects of different MPF concentrations on plant salt tolerance were investigated. The results indicated that MPF could improve the salt tolerance of wheat seedlings. Among the five concentrations (0.05, 0.1, 0.5, 1, and 2 mg/ml), 0.5 and 1 mg/ml MPF were optimal for effective plant salt-resistance activity. These results suggested that MPF extracted from brown seaweed show potential as plant stimulators that may be used to improve salt resistance of plants.

Nodule and Root Zone Microbiota of Salt-Tolerant Wild Soybean in Coastal Sand and Saline-Alkali Soil.

Soil salinization limits crop growth and yield in agro-ecosystems worldwide by reducing soil health and altering the structure of microbial communities. Salt-tolerant plant growth-promoting rhizobacteria (PGPR) alleviate plant salinity stress. Wild soybean (Glycine soja Sieb. and Zucc.) is unique in agricultural ecosystems owing to its ability to grow in saline-alkali soils and fix atmospheric nitrogen via symbiotic interactions with diverse soil microbes. However, this rhizosphere microbiome and the nodule endosymbionts have not been investigated to identify PGPR. In this study, we investigated the structural and functional rhizosphere microbial communities in saline-alkali soil from the Yellow River Delta and coastal soil in China, as well as wild soybean root nodule endosymbionts. To reveal the composition of the microbial ecosystem, we performed 16S rRNA and nifH gene amplicon sequencing on root nodules and root zones under different environmental conditions. In addition, we used culture-independent methods to examine the root bacterial microbiome of wild soybean. For functional characterization of individual members of the microbiome and their impact on plant growth, we inoculated isolates from the root microbiome with wild soybean and observed nodulation. Sinorhizobium/Ensifer accounted for 97% of the root nodule microbiome, with other enriched members belonging to the phyla Actinobacteria, Bacteroidetes, Chloroflexi, Acidobacteria, and Gemmatimonadetes; the genera Sphingomonas, Microbacterium, Arthrobacter, Nocardioides, Streptomyces, Flavobacterium, Flavisolibacter, and Pseudomonas; and the family Enterobacteriaceae. Compared to saline-alkali soil from the Yellow River Delta, coastal soil was highly enriched for soybean nodules and displayed significant differences in the abundance and diversity of ß-proteobacteria, δ-proteobacteria, Actinobacteria, and Bacteroidetes. Overall, the wild soybean root nodule microbiome was dominated by nutrient-providing Sinorhizobium/Ensifer and was enriched for bacterial genera that may provide salt resistance. Thus, this reductionist experimental approach provides an avenue for future systematic and functional studies of the plant root microbiome.

Variation in Chemical Composition and Biological Activities of Flos Chrysanthemi indici Essential Oil under Different Extraction Methods.

Flos Chrysanthemi indici, an important medicinal and aromatic plant in China, is considered to have many different preservative and pharmacological properties. Considering the capability of essential oils (EOs), the present study is conducted to compare different extraction methods in order to improve yield and biological activities. Hydro-distillation (HD), steam-distillation (SD), solvent-free microwave extraction (SFME), and supercritical fluid extraction (SFE) are employed to prepare EOs from Flos Chrysanthemi indici. A total of 71 compounds are assigned by gas chromatography/mass spectrometry (GC-MS) in comparison with retention indices. These include 32 (HD), 16 (SD), 31 (SFME) and 38 (SFE) compounds. Major constituents of EOs differ according to the extraction methods were heptenol, tricosane, camphor, borneol, and eucalyptol. EOs extracted by SFME exhibit higher antioxidant activity. All EOs show varying degrees of antimicrobial activity, with minimum inhibitory concentration (MIC) ranging from 0.0625 to 0.125 mg/mL and SFME and SFE prove to be efficient extraction methods. EOs alter the hyphal morphology of Alternaria alternata, with visible bumps forming on the mycelium. Overall, these results indicate that the extraction method can significantly influence the composition and biological activity of EOs and SFME and SFE are outstanding methods to extract EOs with high yield and antimicrobial activity.

Microwave assisted hydrothermal extraction of polysaccharides from Ulva prolifera: Functional properties and bioactivities.

Sulfated polysaccharides from green tide algae Ulva prolifera were effectively extracted by microwave assisted hydrothermal extraction technology. The properties and bioactivities of polysaccharides could be controlled by extraction conditions. While rhamnose, galacturonic acid and glucose were major monosaccharides at 90°C with 0.01M HCl, glucose was the major monomer at 150°C with 0.1M HCl. Sulfur content increased with temperature and acid concentration, while molecular weight decreased with temperature and concentration. Functional property analysis showed that polysaccharides extracted from 90°C, 0.05M HCl had the best water-holding capacity (41.32g/g) and oil-holding capacity (15.09g/g), and polysaccharides extracted from 150°C, 0.05M HCl had the best foaming properties (foaming capacity 143% and foaming stability 113%, respectively). In addition, polysaccharides extracted from 150°C, 0.1M HCl exhibited higher antioxidant activity and pancreatic lipase inhibition activity. The relationship between polysaccharide compositions/molecular weight and properties/bioactivities was discussed.

Consumption of Black Legumes Glycine soja and Glycine max Lowers Serum Lipids and Alters the Gut Microbiome Profile in Mice Fed a High-Fat Diet.

This study investigated the potential health benefits of two different species of black legume [ Glycine soja Sieb. et Zucc. and Glycine max (L.) Merr.] on diet-induced obesity. C57BL/6 mice were fed a high-fat diet (HFD) supplemented with 20% (w/w) black legume for 12 weeks, and the effects on weight gain, serum lipid levels, liver histology, gut fermentation, and microbiome profile were examined. Consumption of black legumes improved the blood lipid profile and increased fecal propionate and butyrate contents; this was accompanied by a reduction in hepatic steatosis and adipocyte size. High-throughput pyrosequencing of 16S rRNA revealed that black legumes prevented the loss of fecal microbiota diversity and richness caused by a HFD and decreased the relative abundance of Verrucomicrobia while increasing that of Bacteroidetes. Collectively, dietary supplementation with black legumes was found to have attenuated many of the adverse health consequences associated with a HFD and modulated gut microbiota in a positive way.

Low-Molecular-Weightt Polysaccharides From Pyropia yezoensis Enhance Tolerance of Wheat Seedlings (Triticum aestivum L.) to Salt Stress.

Soil salinity is one of the major issues worldwide that affects plant growth and reduces agricultural productivity. Seaweed polysaccharides have been shown to promote crop growth and improve the resistance of plant to abiotic stresses. Pyropia yezoensis is a commercially important edible red alga in Southeast Asia. However, there is little research on the application of polysaccharides from P. yezoensis in agriculture. The molecular weight (MW) of polysaccharides influences their properties. Therefore, in this study, four representative polysaccharides from P. yezoensis (PP) with different MWs (MW: 3.2, 10.5, 29.0, and 48.8 kDa) were prepared by microwave-assisted acid hydrolysis. The relationship between the degradation of polysaccharides from P. yezoensis (DPP) and their effects on plant salt tolerance was investigated. The results showed that exogenous PP and DPPs increased wheat seedling shoot and root lengths, and fresh and dry weights, alleviated membrane lipid peroxidation, increased the chlorophyll content and enhanced antioxidant activities. The expression level examination analysis of several Na+/K+ transporter genes suggested that DPPs could protect plants from the damage of salt stress by coordinating the efflux and compartmentation of Na+. The results demonstrated that polysaccharides could regulate antioxidant enzyme activities and modulate intracellular ion concentration, thereby to protect plants from salt stress damage. Furthermore, there was a significant correlation between the tolerance of wheat seedlings to salt stress and MW of polysaccharides. The results suggested that the lower-MW samples (DPP1, 3.2 kDa) most effectively protect wheat seedlings against salt stress.

Extraction optimization, preliminary characterization and antioxidant activities of polysaccharides from Glycine soja.

Single-factor experiment and Central Composite Design (CCD) was applied to optimize the ultrasound-assisted extraction (UAE) conditions of polysaccharides from Glycine soja (CGPS), and a preliminary characterization of three polysaccharide fractions (CGPS, GPS-1, and GPS-2) and their antioxidant activities were investigated. Under the optimal conditions: ratio of liquid to solid 42.7mL/g, extraction power 293.7W, extraction temperature 68.9°C, and extraction time 34.7min, the experimental CGPS yield was 6.04mg/g. CGPS was further purified by DEAE-cellulose and Sephadex-100 chromatography to obtain two fractions (GPS-1 and GPS-2), and their monosaccharides compositions were characterized by HPLC. Fourier-transform infrared spectra (FT-IR) indicated the chemical structures of them. Moreover, they exhibited high antioxidant activities in a concentration-dependent manner in vitro. In summary, the present study suggested that UAE was a very effective method to extract polysaccharides from Glycine soja and the polysaccharides could be explored as potential antioxidant agents for medicine and function food.