Soluble Polysaccharides Research Articles

Effects of sulfite and freezing co-pretreatment on the volatile fatty acids production of waste activated sludge in anaerobic fermentation

Volatile fatty acids (VFAs) produced during the anaerobic fermentation of waste activated sludge (WAS) are renewable energy sources. However, the biodegradability of untreated WAS is significantly low, thereby imposing a substantial constraint on the generation of VFAs during anaerobic fermentation of WAS. In this study, the experimental results showed that freezing and sulfite co-pretreatment had a synergism on the disintegration of WAS and the production of VFAs. The optimal freezing temperature for VFAs production were −20 °C, 8 h and sulfite dosage of 1400 mg/L resulted in the VFAs reaching a highest concentration of 627.58 mg/L, which was 17.41 times higher than that of the blank group. In addition, the disintegration effect of WAS has been improved, the concentration of soluble chemical oxygen demand (SCOD), proteins and polysaccharides were 7.21, 5.56 and 2.58 times than the blank group, respectively. The microbial community analysis revealed an increase of the OUT of co-pretreatment. Also showed that co-pretreatment could increase the abundance of Levilinea, Unclassified_Anaerolineaceae and Blvii28_wastewater_sludge_group, which might increase VFAs production. Furthermore, compared to sulfite pretreatment or freezing pretreatment, the co-pretreatment significantly enhanced the disintegration efficiency of WAS; shortened the hydrolysis required time for WAS; provided the higher concentration of substrates for VFAs production; and improved the overall efficiency of sludge anaerobic fermentation.

Preparation and characterization of an antioxidant edible film with soluble soybean polysaccharide and pomelo peel extract and its application in lipid packaging

An antioxidant packaging film was prepared by incorporating soluble soybean polysaccharide (SSPS) and pomelo peel extract (PPE), which possessed antioxidant and enhanced mechanical properties for lipids preservation. The effects of PPE dosage on structural, physical, and antioxygenic performance of the SSPS-xPPE films were investigated. Further, the preservation effect of SSPS-5PPE film on lard was also studied. Scanning electron microscopy results indicated that the film stratified with excess PPE (≥0.07 g/g SSPS) remained intact and compact. Hydrogen bonding between SSPS and PPE was shown in the Fourier transform infrared spectra. The incorporating of PPE greatly lessened the light transmittance but enhanced the UV resistance to further optimize the barrier and mechanical properties by reducing the water vapor permeability from 2.79 × 10−14 to 1.37 × 10−14 g⋅mm−2⋅s−1⋅Pa−1, lowering the oxygen permeability from 2.69 × 10−15 to 1.87 × 10−15 cm2⋅s−1⋅Pa−1, and improving the tensile strength from 0.38 to 2.39 MPa. The SSPS-xPPE film possessed good antioxidant ability, with the scavenging activity of SSPS-7PPE film for DPPH and ABTS•+ were 80.34% and 91.68%, respectively. Packaging experiments suggested SSPS-5PPE film could extend the shelf life of lard by approximately 25 d at 20 °C. In brief, the PPE-incorporated SSPS film can be used in packaging to extend the shelf life of lipids.

Structural characterization and adjuvant activity of a water soluble polysaccharide from Poria cocos

Adjuvants, as the essential component of vaccines, are crucial in enhancing the magnitude, breadth and durability of immune responses. Unfortunately, commonly used Alum adjuvants predominantly provoke humoral immune response, but fail to evoke cellular immune response, which is crucial for the prevention of various chronic infectious diseases and cancers. Thus, it is necessary to develop effective adjuvants to simultaneously induce humoral and cellular immune response. In this work, we obtained a water soluble polysaccharide isolated and purified from Poria cocos, named as PCP, and explored the possibility of PCP as a vaccine adjuvant. The PCP, with Mw of 20.112 kDa, primarily consisted of →6)-α-D-Galp-(1→, with a small amount of →3)-β-D-Glcp-(1 → and →4)-β-D-Glcp-(1→. Our results demonstrated that the PCP promoted the activation of dendritic cells (DCs) and macrophages in vitro. As the adjuvant to ovalbumin, the PCP facilitated the activation of DCs in lymph nodes, and evoked strong antibody response with a combination of Th1 and Th2 immune responses. Moreover, compared to Alum adjuvant, the PCP markedly induced a potent cellular response, especially the cytotoxic T lymphocytes response. Therefore, we confirmed that the PCP has great potential to be an available adjuvant for simultaneously inducing humoral and cellular immune responses.

Physical properties, palatability, and mastication of breads with different compositions of soy protein isolate and soybean soluble polysaccharide

Breads with different compositions of wheat flour (WF), soy protein isolate (SPI), and soybean soluble polysaccharide (SSPS) were prepared, and the relationships between their physical and nutritional properties, mastication, palatability were investigated and tests on elderly and young human subjects were conducted. Bread mixed with only SPI (SP1) showed a reduced specific volume and was hard, possibly making it difficult for elderly individuals to swallow. When 10 g of SPSS was added to the mixture (SP2), the bread improved in specific volume, became soft and moderately hard, and was as palatable as regular bread (control; without SPI and SPSS) for younger and older people. However, when 20 g of SSPS was added (SP3), the adhesiveness increased and palatability was impaired. In addition, SP2 bread required increased number of chews and chewing time compared to that required for control bread in older people but the difficulty of swallowing was similar for both in the sensory evaluation. SP2 bread can increase the intake of protein and dietary fiber and increase the number of chews without affecting palatability, and SPI and SSPS mixed bread was considered useful for maintaining the chewing ability and nutritional status of older people.

The physicochemical stability and in vivo gastrointestinal fates of flaxseed oil bodies with the introduction of soluble flaxseed gum polysaccharides

The natural oil bodies (OBs) were considered minimally processed entities for delivering bioactive lipids and minor lipid concomitants, such as α-linolenic acid (ALA), tocopherols, etc. when incorporated into food systems. The current study investigated the physicochemical stability and in vivo gastrointestinal digestion of flaxseed OBs with the introduction of soluble flaxseed gum polysaccharides (SFG), which always consistently coexisted in flaxseed milk. The results showed that the particle sizes of flaxseed OB emulsions consistently decreased by 37.46% (p < 0.05), while the zeta potential values gradually increased by 60.91% (p < 0.05) as the SFG concentrations raised from 0.1% to 0.5% (wt %). SFG improved the physical stability of flaxseed OB emulsions by preventing bridging flocculation among adjacent OBs, and achieving the movement restriction of single OBs via the direct interface anchoring and network structure formation in bulk aqueous phase. SFG apparently suppressed the gastrointestinal lipolysis rate of flaxseed OBs due to the complex coacervation with intrinsic interfacial proteins, subsequent deep encapsulation and gastric emptying delaying of OB remnants. Then, the slower micellar absorption and chylomicron transport within rat enterocytes were occurred, contributing to the suppressed ALA accumulation and subsequent conversion into n-3 long chain fatty acids in rat upper jejunum. Collectively, the introduction of SFG in flaxseed OBs at high concentration allows lower intestinal ALA bioaccessibility.

Electrochemistry promotion of Fe(Ⅲ)/Fe(Ⅱ) cycle for continuous activation of PAA for sludge disintegration: Performance and mechanism

In this study, electrochemistry was used to enhance the advanced oxidation of Fe(Ⅱ)/PAA (EC/Fe(Ⅱ)/PAA) to disintegrate waste activated sludge, and its performance and mechanism was compared with those of EC, PAA, EC/PAA and Fe(Ⅱ)/PAA. Results showed that the EC/Fe(Ⅱ)/PAA process effectively improved sludge disintegration and the concentrations of soluble chemical oxygen demand, polysaccharides and nucleic acids increased by 62.85%, 41.15% and 12.21%, respectively, compared to the Fe(Ⅱ)/PAA process. Mechanism analysis showed that the main active species produced in the EC/Fe(Ⅱ)/PAA process were •OH, R–O• and FeIVO2+. During the reaction process, sludge flocs were disrupted and particle size was reduced by the combined effects of active species oxidation, electrochemical oxidation and PAA oxidation. Furthermore, extracellular polymeric substances (EPS) was degraded, the conversion of TB-EPS to LB-EPS and S-EPS was promoted and the total protein and polysaccharide contents of EPS were increased. After sludge cells were disrupted, intracellular substances were released, causing an increase in nucleic acids, humic acids and fulvic acids in the supernatant, and resulting in sludge reduction. EC effectively accelerated the conversion of Fe(Ⅲ) to Fe(Ⅱ), which was conducive to the activation of PAA, while also enhancing the disintegration of EPS and sludge cells. This study provided an effective approach for the release of organic matter, offering significant benefits in sludge resource utilization.

Encapsulation of luteolin by self-assembled Rha/SSPS/SPI nano complexes: Characterization, stability, and gastrointestinal digestion in vitro

Luteolin has anti-inflammatory, antioxidant, and anti-tumor functions, but its poor water solubility and stability limit its applications in foods as a functional component. In this study, the nanocomposites loading luteolin (Lut) with soybean protein isolate (SPI), soluble soybean polysaccharide (SSPS) and/or rhamnolipid (Rha) were prepared by layer-by-layer shelf assembly method, and their properties were also evaluated. The results showed that Rha/SPI/Lut had the smallest particle size (206.24 nm) and highest loading ratio (8.03 μg/mg) while Rha/SSPS/SPI/Lut had the highest encapsulation efficiency (82.45 %). Rha interacted with SPI through hydrophobic interactions as the main driving force, while SSPS attached to SPI with only hydrogen bonding. Furthermore, the synergistic effect between Rha and SSPS was observed in Rha/SSPS/SPI/Lut complex, in consequence, it had the best thermal and storage stability, and the slowest release in gastrointestinal digestion. Thus, this approach provided an alternative way for the application of luteolin in functional foods.

A Comparative Study of Composition and Soluble Polysaccharide Content between Brewer's Spent Yeast and Cultured Yeast Cells.

Yeast, crucial in beer production, holds great potential owing to its ability to transform into a valuable by-product resource, known as brewer's spent yeast (BSY), with potentially beneficial physiological effects. This study aimed to compare the composition and soluble polysaccharide content of Brewer's spent yeast with those of cultured yeast strains, namely Saccharomyces cerevisiae (SC) and S. boulardii (SB), to facilitate the utilization of BSY as an alternative source of functional polysaccharides. BSY exhibited significantly higher carbohydrate content and lower crude protein content than SC and SB cells. The residues recovered through autolysis were 53.11%, 43.83%, and 44.99% for BSY, SC, and SB, respectively. Notably, the polysaccharide content of the BSY residue (641.90 μg/mg) was higher than that of SC (553.52 μg/mg) and SB (591.56 μg/mg). The yields of alkali-extracted water-soluble polysaccharides were 33.62%, 40.76%, and 42.97% for BSY, SC, and SB, respectively, with BSY comprising a comparable proportion of water-soluble saccharides made with SC and SB, including 49.31% mannan and 20.18% β-glucan. Furthermore, BSY demonstrated antioxidant activities, including superoxide dismutase (SOD), ABTS, and DPPH scavenging potential, suggesting its ability to mitigate oxidative stress. BSY also exhibited a significantly higher total phenolic compound content, indicating its potential to act as an effective functional food material.

Gel-confined fabrication of fully bio-based filtration membrane for green capture and rapid detection of airborne microbes

Air filtration has become a desirable route for collecting airborne microbes. However, the potential biotoxicity and sterilization of current air filtration membranes often lead to undesired inactivation of captured microbes, which greatly limits microbial non-traumatic transfer and recovery. Herein, we report a gel-confined phase separation strategy to rationally fabricate a fully bio-based filtration membrane (SGFM) using soluble soybean polysaccharide and gelatin. The versatile SGFM features fascinating honeycomb micro-nano architecture and hierarchical interconnected porous structures for microbial capture, and achieves a lower pressure drop, higher interception efficiency (99.3%), and superior microbial survivability than commercial gelatin filtration membranes. Particularly, the water-dissolvable SGFM can greatly simplify the elution and extraction process after bioaerosol sampling, thereby bringing about maximum sample transfer and vigorous recovery of collected microbes. Meanwhile, green capture coupled with ATP bioluminescence endows the SGFM with rapid and quantitative detection capability for airborne microbes. This work may pave the way for designing green protocols for the detection of bioaerosols.

Degradation of organic compounds by a novel Bacillus cereus BX16 in starch waste

Starch wastes are organic pollutants that have a negative impact on the environment. Bacillus cereus BX16, a newly isolated strain with the capacity to exclusively digest starch, was separated and purified using food waste (FW). The efficiency of starch breakdown by Bacillus cereus BX16 was greatly influenced by operational parameters, such as organic load rates (OLRs), pH and temperature. According to the findings, Bacillus cereus BX16 degraded more effectively at the starting starch concentration of 20 g/L. Further optimization resulted in approximately 90% and 99% removal of soluble chemical oxygen demand (SCOD) and polysaccharides, over a wide range of settings (pH 5.0–9.0, 25 °C to 37 °C). In addition, when starch was effectively degraded, 90% of the residual SCOD (<5000 mg/L) consisted mainly of proteins and volatile fatty acids (VFAs). In contrast, in the absence of active Bacillus cereus BX16, the residual polysaccharide and glucose concentration jumped to 20,000 mg/L. Ultimately, the unique biological method of treating starch waste with Bacillus cereus BX16 also proves the effectiveness of microbial treatment.

Extraction of Heracleum dissectum soluble dietary fiber by different methods: Structure and antioxidant properties.

Heracleum dissectum is rich in nutrients, but there is little research on its soluble dietary fiber (SDF). In this study, SDF from H. dissectum was extracted by enzyme extraction (E-SDF), enzyme chemical extraction (EC-SDF), and fermentation extraction (F-SDF). The composition, molecular weight (Mw), structural characterization, and antioxidant activity of SDF extracted by the three methods were compared. This study showed that different extraction methods lead to differences in their structure. The Mw results showed that F-SDF had the largest Mw, the structure of SDF could be destroyed by enzymatic hydrolysis, and large molecules could be converted into small molecules. The monosaccharide composition analysis showed that the main sugars of E-SDF, EC-SDF, and F-SDF were galacturonic acid and galactose, and the main components of the three SDF samples were hemicellulose hydrolyzed pectin and soluble polysaccharide. Notably, E-SDF had the greatest antioxidant effect at the same concentration. In summary, different extraction methods can affect the structure and antioxidant capacity of H. dissectum SDF, among which E-SDF has potential as a functional food ingredient.

Flexibility, dissolvability, heat-sealability, and applicability improvement of pullulan-based composite edible films by blending with soluble soybean polysaccharide

This study aimed to prepare a heat-sealable, water-soluble, edible film based on pullulan (PUL)/soluble soybean polysaccharide (SSPS) for the portable packaging of convenience foods. The effects of the PUL/SSPS ratios on the microstructure, physicochemical properties, barrier properties, and mechanical properties of the PUL/SSPS films were explored. Fourier-transform infrared spectroscopy and X-ray diffraction showed an apparent hydrogen bonding interaction between SSPS and PUL in the PUL/SSPS films. As the SSPS proportion in the PUL/SSPS films increased, the water contact angle, moisture content, water vapor permeability, solubility, oxygen permeability, flexibility, and antioxidant activity increased, whereas light transmittance decreased. The heat-seal strength of the P9S1 film (PUL/SSPS ratio of 9:1) is slightly lower than that of the PUL film (p > 0.05). Furthermore, the application potential of the PUL/SSPS films for packaging peptide powder was evaluated. The P9S1 film exhibited a satisfactory packaging effect and was completely dissolved in water with low turbidity. Therefore, the P9S1 film is a promising packaging material for convenient powdered foods.

Advancing soy protein isolate-ulvan film physicochemical properties and antioxidant activities through strategic high-pressure homogenization technique

Soy protein-based films often exhibit poor properties, including limited mechanical strength, stability, and bioactivity, which hinder their extensive application in the food industry, particularly in edible packaging. To enhance the properties of soy protein-based films, we employed high-pressure homogenization (HPH) to modify the soybean protein isolate (SPI) molecules and sought to cross-link SPI with ulvan polysaccharide, which possesses distinctive bioactivities. The results confirmed that soluble ulvan polysaccharides were incorporated into the cross-linking system through hydrogen bonding. Results indicated that HPH treatment enhanced SPI's solubility and surface hydrophobicity (H0), promoting hydrogen bonding and hydrophobic interactions between SPI and ulvan, as evidenced by ζ-potential and turbidity measurements. Structural and microstructural analyses of both individual SPI and composite films, using FT-IR, XRD, CD and SEM, demonstrated a high compatibility between HPH-treated SPI and ulvan. The incorporation of ulvan reduced the films' tensile strength (TS), but higher pressure significantly improved it (p < 0.05). Post-HPH modification, the films exhibited increased contact angle and swelling capacity (p < 0.05), indicating enhanced hydrophobicity. Higher pressure treatments resulted in more opaque and yellowish films, thereby diminishing ultraviolet light transmission. Thermal stability analyses, via TGA-DSC, showed that U-HSPI films had improved thermal stability compared to pure SPI films. Moreover, ulvan inclusion boosted the antioxidant capacity of SPI films, especially after HPH treatment. Overall, this study confirms that HPH modification substantially influences the properties and activities of SPI-based films, and the complex films based on SPI and ulvan with improved physicochemical and antioxidant properties exhibit a great potential in the food packaging field.

Plasticizers inhibit food waste anaerobic digestion performance by affecting microbial succession and metabolism

The widely existed plastic additives plasticizers in organic wastes possibly pose negative influences on anaerobic digestion (AD) performance, the direct evidence about the effects of plasticizers on AD performance is still lacking. This study evaluated the influencing mechanism of two typical plasticizers bisphenol A (BPA) and dioctyl phthalate on the whole AD process. Results indicated that plasticizers addition inhibited methane production, and the inhibiting effects were reinforced with the increase of concentration. By contrast, 50 mg/L BPA exhibited the strongest inhibition on methane production. Physicochemical analysis showed plasticizers inhibited the metabolism efficiency of soluble polysaccharide and volatile fatty acids. Microbial communities analyses suggested that plasticizers inhibited the direct interspecies electron transfer participators of methanogenic archaea (especially Methanosarcina) and syntrophic bacteria. Furthermore, plasticizers inhibited the methane metabolisms, key coenzymes (CoB, CoM, CoF420 and methanofuran) biosynthesis and the metabolisms of major organic matters. This study shed light on the effects of plasticizers on AD performance and provided new insights for assessing the influences of plasticizers or plastic additives on the disposal of organic wastes.

Investigation of the nutritional and functional roles of a combinational use of xylanase and β-glucanase on intestinal health and growth of nursery pigs

BackgroundXylanase and β-glucanase combination (XG) hydrolyzes soluble non-starch polysaccharides that are anti-nutritional compounds. This study aimed to evaluate the effects of increasing levels of XG on intestinal health and growth performance of nursery pigs.MethodsForty pigs (6.5 ± 0.4 kg) were assigned to 5 dietary treatments and fed for 35 d in 3 phases (11, 9, and 15 d, respectively). Basal diets mainly included corn, soybean meal, and corn distiller’s dried grains with solubles, contained phytase (750 FTU/kg), and were supplemented with 5 levels of XG at (1) 0, (2) 280 TXU/kg xylanase and 125 TGU/kg β-glucanase, (3) 560 and 250, (4) 840 and 375, or (5) 1,120 and 500, respectively. Growth performance was measured. On d 35, all pigs were euthanized and jejunal mucosa, jejunal digesta, jejunal tissues, and ileal digesta were collected to determine the effects of increasing XG levels and XG intake on intestinal health.ResultsIncreasing XG intake tended to quadratically decrease (P = 0.059) viscosity of jejunal digesta (min: 1.74 mPa·s at 751/335 (TXU/TGU)/kg). Increasing levels of XG quadratically decreased (P < 0.05) Prevotellaceae (min: 0.6% at 630/281 (TXU/TGU)/kg) in the jejunal mucosa. Increasing XG intake quadratically increased (P < 0.05) Lactobacillaceae (max: 40.3% at 608/271 (TXU/TGU)/kg) in the jejunal mucosa. Increasing XG intake quadratically decreased (P < 0.05) Helicobacteraceae (min: 1.6% at 560/250 (TXU/TGU)/kg) in the jejunal mucosa. Increasing levels of XG tended to linearly decrease (P = 0.073) jejunal IgG and tended to quadratically increase (P = 0.085) jejunal villus height to crypt depth ratio (max: 2.62 at 560/250 (TXU/TGU)/kg). Increasing XG intake tended to linearly increase the apparent ileal digestibility of dry matter (P = 0.087) and ether extract (P = 0.065). Increasing XG intake linearly increased (P < 0.05) average daily gain.ConclusionsA combinational use of xylanase and β-glucanase would hydrolyze the non-starch polysaccharides fractions, positively modulating the jejunal mucosa-associated microbiota. Increased intake of these enzyme combination possibly reduced digesta viscosity and humoral immune response in the jejunum resulting in improved intestinal structure, and ileal digestibility of nutrients, and finally improving growth of nursery pigs. The beneficial effects were maximized at a combination of 550 to 800 TXU/kg xylanase and 250 to 360 TGU/kg β-glucanase.

Wine fermentation process evaluation through NMR analysis: Polysaccharides, ethanol quantification and biological activity

Winemaking production is old knowledge of the combination of saccharification and fermentation processes. During the fermentation process, ethanol concentration is one of the main key parameters that provides the quality of wine and is linked to the consumption of carbohydrates present in wine. In this work was determined the better fermentation time, where the wine retains its highest concentration of ethanol and a higher concentration of the polysaccharides of Bordo wine of Vitis labrusca by 1D and 2D NMR measurements. The study provides information on the polysaccharide content for improving features and quality control of winemaking. Moreover, following previous studies by our group (de Lacerda Bezerra et al., 2018, de Lacerda Bezerra, Caillot, de Oliveira, Santana-Filho, & Sassaki, 2019; Stipp et al., 2023) showed that the soluble polysaccharides also inhibited the production of inflammatory cytokines (TNF-α and IL-1β) and mediator (NO) in macrophage cells stimulated with LPS, bringing some important health benefits of wine.

Pea protein isolate-soluble soybean polysaccharides electrostatic assembly: effect of pH, biopolymer mass ratio and heat treatment.

In past years, thousands of protein-polysaccharide complexes have been investigated to modify protein characteristics and functionality in food systems. However, the interaction between pea protein isolate (PPI) and soluble soybean polysaccharide (SSPS) has not been thoroughly characterized yet. In the present study, the phase behavior of PPI and SSPS mixtures was analyzed as a function of PPI:SSPS mixing ratio (1:1 to 1:0.10) and pH (7.0 to 2.0), showing that these biopolymers could be electrostatically assembled at 1:1 to 1:0.25 mixing ratios and 4.0 to 3.0 pH values. Then, the characteristics of the PPI-SSPS complexes were studied before and after heating (90 °C and 30 min) by ζ-potential, surface hydrophobicity, protein solubility, particle size distribution and physical stability for 56 days. By lowering the pH and PPI:SSPS mixing ratio, the complexes showed increased solubility, changed 𝜁-potential and higher physical stability. By heating, the complexes presented increased hydrophobicity and physical stability. Overall, PPI-SSPS complexes increased the protein solubility, reduced the particle size, and changed both the ζ-potential and the surface hydrophobicity with respect to PPI control, allowing stabilization of the colloidal system and broadening the possible applications of these high-quality proteins in acidic food systems. © 2024 Society of Chemical Industry.

Structural characterization of the polysaccharide from the black crystal region of Inonotus obliquus and its effect on AsPC-1 and SW1990 pancreatic cancer cell apoptosis

In this study, one water soluble polysaccharide (IOP1–1) with a weight average molecular weight of 6886 Da was obtained from the black crystal region of Inonotus obliquus by hot water extraction, DEAE-52 cellulose extraction and Sephadex-100 column chromatography purification. Structural analysis indicated that IOP1–1 was a glucan with a main chain composed of α-Glcp-(1 → 4)-α-Glcp-(1 → 4)-β-Glcp-(1 → 4)-β-Glcp-(1 → 4)-α-Glcp-(1 → 6)-β-Glcp-(1 → 4)-α-Glcp-(1 → 3)-β-Glcp-(1→. The CCK-8 assay results showed that IOP1–1 inhibited AsPC-1 and SW1990 pancreatic cancer cell proliferation in a concentration-dependent manner. Flow cytometric analysis revealed that IOP1–1 induced cell cycle arrest in AsPC-1 and SW1990 cells. Hoechst 33342 staining and Annexin V-FITC/PI double staining analysis showed that IOP1–1 could induce apoptosis in AsPC-1 and SW1990 cells. Furthermore, western blot analysis confirmed that IOP1–1 could induce apoptosis in AsPC-1 and SW1990 pancreatic cancer cells through three pathways: the mitochondrial pathway, the death receptor pathway, and endoplasmic reticulum stress. According to these research data, IOP1–1 may be utilized as an adjuvant treatment to anticancer medications, opening up new application prospects and opportunities.

Identification of Indicator Genes for Agar Accumulation in Gracilariopsis lemaneiformis (Rhodophyta).

Agar, as a seaweed polysaccharide mainly extracted from Gracilariopsis lemaneiformis, has been commercially applied in multiple fields. To investigate factors indicating the agar accumulation in G. lemaneiformis, the agar content, soluble polysaccharides content, and expression level of 11 genes involved in the agar biosynthesis were analysed under 4 treatments, namely salinity, temperature, and nitrogen and phosphorus concentrations. The salinity exerted the greatest impact on the agar content. Both high (40‱) and low (10‱, 20‱) salinity promoted agar accumulation in G. lemaneiformis by 4.06%, 2.59%, and 3.00%, respectively. The content of agar as a colloidal polysaccharide was more stable than the soluble polysaccharide content under the treatments. No significant correlation was noted between the two polysaccharides, and between the change in the agar content and the relative growth rate of the algae. The expression of all 11 genes was affected by the 4 treatments. Furthermore, in the cultivar 981 with high agar content (21.30 ± 0.95%) compared to that (16.23 ± 1.59%) of the wild diploid, the transcriptional level of 9 genes related to agar biosynthesis was upregulated. Comprehensive analysis of the correlation between agar accumulation and transcriptional level of genes related to agar biosynthesis in different cultivation conditions and different species of G. lemaneiformis, the change in the relative expression level of glucose-6-phosphate isomerase II (gpiII), mannose-6-phosphate isomerase (mpi), mannose-1-phosphate guanylyltransferase (mpg), and galactosyltransferase II (gatII) genes was highly correlated with the relative agar accumulation. This study lays a basis for selecting high-yield agar strains, as well as for targeted breeding, by using gene editing tools in the future.

Influence of Grape Flesh on the Retention and Composition of Polyphenols from Skins and Seeds.

This study examined the impact of grape flesh polysaccharide, protein, and amino acid contents on polyphenol retention from skins and seeds in Pinot noir (Vitis vinifera) and cold-hardy interspecific cultivars Marquette and Frontenac (Vitis spp.). After isolating grape tissues (skin, seed, and flesh), they were soaked either individually or combined with other tissues in a wine-like solution for up to 7 days. Findings revealed that flesh significantly reduces the concentration of condensed tannin, and mono- and diglucoside forms of anthocyanins in the supernatants, due to its rich content in polysaccharides and proteins. Frontenac skin and flesh tissues were the main sources of soluble proteins, amino acids, and soluble polysaccharides. Surprisingly, Marquette exhibited a higher retention of skin tannin than Pinot noir, likely due to its smaller tannin molecular mass, and a potential competitive effect with anthocyanins for the binding sites of flesh.