Dough preparation and performance are two critical factors influencing the final quality of wheat products. The influence of high and low methoxyl pectins on empirical and dynamic rheological properties of dough and C...Dough preparation and performance are two critical factors influencing the final quality of wheat products. The influence of high and low methoxyl pectins on empirical and dynamic rheological properties of dough and Chinese steamed bread(CSB)quality were investigated. Different concentrations of high methoxyl apple pectin(HMAP), low methoxyl apple pectin(LMAP),and amidation apple pectin(ALMAP) were tested. Results from dynamic and empirical rheological tests indicated that all concentrations of pectins tested(0.2%, 0.6%, and 1%) negatively affected the gluten network. The low methoxyl pectins, LMAP and ALMAP, which had higher anionic densities, resulted in a pronounced weakening of the dough. Meanwhile, dough fermentation properties improved in the presence of appropriate pectins concentrations, and higher maximum dough height, stability of dough pore space, and gas retention were recorded. HMAP was the pectin most effective in influencing dough fermentation properties at all tested concentrations. Regarding CSB quality, textural properties, specific volume, moisture content, and water-holding capacity were analyzed. Generally, the textural properties of CSB were improved, including improved springiness and decreased hardness and chewiness, when 0.2%–0.6% HMAP or LMAP was used. The specific volume of CSB was increased by adding 0.2%–1% HMAP,0.6%–1% LMAP, or 0.2%–0.6% ALMAP. Moreover, CSB moisture loss was progressively reduced in the presence of different pectins at all tested concentrations during storage. In conclusion, pectins, especially HMAP, are good additives for improving the fermentation properties of dough and overall quality of CSB.展开更多
Plasmodesmata(PD)create symplasmic continuity in plant tissues by connecting the cytoplasm of neighboring cells.Molecular movement through PD is important for many processes,including organ development,pathogen defens...Plasmodesmata(PD)create symplasmic continuity in plant tissues by connecting the cytoplasm of neighboring cells.Molecular movement through PD is important for many processes,including organ development,pathogen defense,environmental acclimation,and nutrient allocation.Elucidating the kinetics of PD transport and its regulation is essential for understanding these processes.展开更多
Pectins are complex cell wall polysaccharides important for many aspects of plant development. Recent studies have discovered extensive physical interactions between pectins and other cell wall components,implicating ...Pectins are complex cell wall polysaccharides important for many aspects of plant development. Recent studies have discovered extensive physical interactions between pectins and other cell wall components,implicating pectins in new molecular functions. Pectins are often localized in spatially-restricted patterns, and some of these non-uniform pectin distributions contribute to multiple aspects of plant development, including the morphogenesis of cells and organs. Furthermore, a growing number of mutants affecting cell wall composi- tion have begun to reveal the distinct contributions of different pectins to plant development. This review discusses the interactions of pectins with other cell wall components, the functions of pectins in controlling cellular morphology, and how non-uniform pectin composition can be an important determinant of developmental processes.展开更多
Abstract: Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP e...Abstract: Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP epitopes); JIM 8 (recognizes a subset of AGP epitopes); and JIM 5 and JIM 7 (epitopes of pectins esterified to various degrees). In the stem apex meristem (SAM) of the cucumber, epitopes of MAC 207, JIM 7, and JIM 5 were localized in the cells from second to third peripheral layers when the sex organ primodium began to differentiate; epitopes of MAC 207 and JIM 5 were also detected in the ragged edge cells. A very dense labeling signal with MAC 207 was observed in the carpel and pistil primodium. The AGP epitopes recognized by JIM 8 were localized in the anther of the male flower and the anther-like portion of the stagnant stamen of the female flower. This suggests that the AGPs and pectins in the SAM of the cucumber are closely associated with the differentiation of the SAM, from meristematic cells to floral primodium. The subset of AGPs recognized by JIM 8 may play an important role in stamen formation.展开更多
The plant cell wall is an extremely complicated natural nanoscale structure composed of cellulose microfibrils embedded in a matrix of noncellulosic polysaccharides,further reinforced by the phenolic compound lignins ...The plant cell wall is an extremely complicated natural nanoscale structure composed of cellulose microfibrils embedded in a matrix of noncellulosic polysaccharides,further reinforced by the phenolic compound lignins in some cell types.Such a network formed by the interactions of multiscale polymers actually reflects functional form of the cell wall to meet the requirements of plant cell functionalization.Therefore,how plants assemble cell wall functional structure is fundamental in plant biology and critical for crop trait formation and domestication as well.Due to the lack of effective analytical techniques to characterize this fundamental but complex network,it remains difficult to establish direct links between cell-wall genes and phenotypes.The roles of plant cell walls are often underestimated as indirect.Over the past decades,many genes involved in cell wall biosynthesis,modification,and remodeling have been identified.The application of a variety of state-of-the-art techniques has made it possible to reveal the fine cell wall networks and polymer interactions.Hence,many exciting advances in cell wall biology have been achieved in recent years.This review provides an updated overview of the mechanistic and conceptual insights in cell wall functionality,and prospects the opportunities and challenges in this field.展开更多
Biomacromolecules derived from plant-based traditional Chinese medicines play a pivotal role in natural drug research.Ginseng,the root of Panax ginseng C.A.Meyer,has attracted significant attention due to its diverse ...Biomacromolecules derived from plant-based traditional Chinese medicines play a pivotal role in natural drug research.Ginseng,the root of Panax ginseng C.A.Meyer,has attracted significant attention due to its diverse pharmacological activities and broad therapeutic applications.This review focuses on specific active macromolecules obtained from ginseng,including pectin,exosomes,proteins,and dietary fibers.These components possess unique structural characteristics and biological activities that offer novel insights into the multifaceted applications of ginseng.To systematically assess this field,we reviewed literature published over the past 60 years and identified 119 relevant studies investigating the structural composition,pharmacological activity,and potential applications of P.ginseng biomacromolecules.By highlighting their crucial role in promoting health and enhancing disease resistance,this review synthesizes the latest research findings on ginseng’s pharmacological effects,providing new perspectives and strong theoretical support for clinical drug development.展开更多
Hexavalent chromium,when present in high concentrations,causes a serious threat to the ecosystem.This can lead to severe ecological damage and persistent environmental issues,making it a significant concern for long-t...Hexavalent chromium,when present in high concentrations,causes a serious threat to the ecosystem.This can lead to severe ecological damage and persistent environmental issues,making it a significant concern for long-term sustainability.Thus,there is a strong need for high-performing adsorbents to remove high concentrations of Cr(VI)from the environment.In the present study,Citrus Limetta peels were utilised to produce pristine biochar,which was treated with iron oxides to generate magnetic biochar and modified with chitosan,sodium alginate,and pectin to produce respective modified biochar.Among all five biochars,Chitosan-modified biochar(CMBC)displayed the highest removal efficiency towards Cr(VI)from water with a maximum adsorption capacity of 152.44 mg/g and a removal capacity of 76.22%.Furthermore,adsorption kinetics indicates that the adsorption process is a pseudo-second order-kinetic model with R^(2)and qe of 0.99 and 99 mg/g,respectively.The Langmuir isotherm best describes the adsorption process.After five regenerative cycles,the removal efficiency was maintained at up to 71.80%.This work highlights the remarkable potential of engineered biochar in wastewater treatment.展开更多
Tropomyosin(TM)is the predominant allergenic protein in shrimp,which has induced IgE-mediated food allergy reactions.In this study,Lit v 1 was purified from Penaeus vannamei muscles,which were glyco sylated by pectic ...Tropomyosin(TM)is the predominant allergenic protein in shrimp,which has induced IgE-mediated food allergy reactions.In this study,Lit v 1 was purified from Penaeus vannamei muscles,which were glyco sylated by pectic oligosaccharides.The results showed that di-galacturonic acid(DGA)and galacturonic acid(GA)induced the unfolding of the primary protein structure of TM,and changedα-helical structure,and IgE binding capacity.In addition,compared with TM-sensitized BALB/c mice,GA-modified TM(GA-TM)and DGA-modified TM(DGA-TM)were insufficient to stimulate sensitization,and significantly reduced the hypersecretion of IgE,IgG1,HIS,and IL-4,up-regulated IgG2a and IFN-y levels to improve imbalanced Th1/Th2,Treg/Th17 immunity,and promoted mRNA expression of tight junction proteins.Together,this study confirmed that glycosylation modification alleviated sensitization by altering TM structure,reducing IgE binding allergic inflammatory response,and regulating cytokine immune balance.Overall,these results indicated that glycosylation modification was a promising method for decreasing the allergenic reactivity of allergic proteins.展开更多
Pectin is a natural polysaccharide with a complex structure consisting of linear and branched regions rich in galacturonic acid.The growing interest in orange peel pectin can be attributed to its abundant supply.Accor...Pectin is a natural polysaccharide with a complex structure consisting of linear and branched regions rich in galacturonic acid.The growing interest in orange peel pectin can be attributed to its abundant supply.According to statistics,about 10 million tons of orange peel waste are produced worldwide each year.Traditionally,the extraction and utilization of pectin have focused on its gelling,thickening,and stabilizing properties in food.However,as more and more research teams have found that pectin has good biocompatibility,biodegradability and easy chemical modification,its potential in drug delivery systems,tissue engineering,and wound healing is gradually being explored.This review focuses on orange peel pectin polysaccharides and discusses its traditional and modern extraction techniques,especially the advanced method of subcritical water extraction.This study also outlines the structural modifications of pectin such as methylation and acetylation,and introduces its antioxidant and anticancer biological activities and their emerging roles in the development of advanced biomaterials such as bone tissue engineering and fibre pad dressings.展开更多
In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase （PPO） and color of banana juice during hot water ex-traction were discussed based on the theory in which heat ...In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase （PPO） and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO.展开更多
The changes of physiological and biochemical indices in jujube fruits during the late development were investigated from 6-year-old jujube trees （Zizyphus jujuba Mill. cv. Lingwuchangzao）. The results showed that th...The changes of physiological and biochemical indices in jujube fruits during the late development were investigated from 6-year-old jujube trees （Zizyphus jujuba Mill. cv. Lingwuchangzao）. The results showed that the flesh firmness decreased slowly from white-green stage to full-red stage, being significantly related with the developmental maturity of jujube fruits negatively, the correlation coefficient reached -0.980 3^＊＊. The contents of ascorbic acid and titratable acid in jujube fruits were significantly related with the developmental process of jujube fruits negatively or positively, the correlation coef- ficients were -0. 973 1^＊＊and ＋ 0. 974 6^ ＊ ＊ , respectively. The contents of soluble solids, total sugar, and sucrose increased with jujube ripening, while the relative sweetness of jujube fruits showed the same variation pattern, the correlation coefficients were 0. 996 6 ^＊ ＊ , 0. 988 0^＊＊ , and 0. 982 8 ^＊ ＊ , respectively. Before white-green stage during fruit development, the accumulation of monosaccharide was predominant in jujube fruits, following a fast accumulation of sucrose, indicating that the main component of sugars is sucrose at the crisp-ripe stage. Furthermore, the starch content of the flesh reached the peak at about thirty percentage of jujube maturity, being 51,54 mg/100 g.FW. The respiratory rates varied between 10 mg/（ kg.h） and CO2 26 mg/（ kg.h） after fruit turning red and before softening, indicating a non-climacteric respiratory type.展开更多
We studied the effect of two independent variables, the pectin/calcium chloride weight ratio and the overall matrix weight in HPMC/pectin/calcium matrix tablet, on the release of indomethacin. A two-factor 5-level cen...We studied the effect of two independent variables, the pectin/calcium chloride weight ratio and the overall matrix weight in HPMC/pectin/calcium matrix tablet, on the release of indomethacin. A two-factor 5-level central composite experimental design was employed. Responses of the Peppas correlation parameters n and K and the 10% release time （T0.1） were optimized by response surface methodology. Significant effect of the independent variables on the biphasic release parameters, n and K, was observed. N, K and T0.1 were well fitted with the second-order quadratic equations rather than linear equations. Moreover, the mathematic fitting and the response surfaces showed significant cross-interaction between the pectin/calcium chloride ratio and the overall matrix weight. The optimal formulation with larger n, longer T0.1 and smaller K consisted of medium pectin/calcium chloride ratio around 1.0 and medium matrix weight around 200 mg. Validation studies on the optimal formulations showed good predictability of the n, K and T0.1 values with biases within the range of-7.33% and 6.26%. Our results support that central composite design can be used to optimize drug release from HPMC/pectin/calcium matrix tablet with high predictability.展开更多
AIM: To discuss the expression of glactin-3 in liver metastasis of colon cancer and its inhibition by modi- fied citrus pectin (MCP) in mice. METHODS: Seventy-five Balb/c mice were randomly di- vided into negative con...AIM: To discuss the expression of glactin-3 in liver metastasis of colon cancer and its inhibition by modi- fied citrus pectin (MCP) in mice. METHODS: Seventy-five Balb/c mice were randomly di- vided into negative control group (n = 15), positive con- trol group (n = 15), low MCP concentration group (n = 15), middle MCP concentration group (n = 15) and high MCP concentration group (n = 15). CT26 colon cancer cells were injected into the subcapsule of mouse spleen in positive control group, low, middle and high MCP concentrations groups, except in negative control, to set up a colon cancer liver metastasis model. The concen- tration of MCP in drinking water was 0.0%, 0.0%, 1.0%, 2.5% and 5.0% (wt/vol), respectively. Liver metastasis of colon cancer was observed after 3 wk. Enzyme-linked immunosorbent assay (ELISA) was used to detect the concentration of galectin-3 in serum. Expression of ga- lectin-3 in liver metastasis was detected by immunohis- tochemistry. RESULTS: Except for the negative group, the percent- age of liver metastasis in the other 4 groups was 100%, 80%, 73.3% and 60%, respectively. The number of liver metastases in high MCP concentration group was significantly less than that in positive control group (P = 0.008). Except for the negative group, the median volume of implanted spleen tumor in the other 4 groups was 1.51 cm3, 0.93 cm3, 0.77 cm3 and 0.70 cm3, respec- tively. The volume of implanted tumor in middle and high MCP concentration groups was significantly smaller than that in positive control group (P = 0.019; P = 0.003). The concentration of serum galectin-3 in positive control and MCP treatment groups was significantly higher than that in the negative control group. However, there was no significant difference between them. Except for the negative control group, the expression of galectin-3 in liver metastases of the other 4 groups showed no sig- nificant difference. CONCLUSION: Expression of galetin-3 increases sig- nificantly in liver metastasis of colon cancer, which can be effectively inhibited by MCP.展开更多
AIM: To compare the effectiveness of standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori (H. pylori ) eradication in a randomized, double-blinded, comparative clinical trial in C...AIM: To compare the effectiveness of standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori (H. pylori ) eradication in a randomized, double-blinded, comparative clinical trial in China. METHODS: A total of 215 H. pylori -positive patients were enrolled in the study and randomly allocated into three groups: group A (n = 72) received a 10-d bismuth pectin quadruple therapy (20 mg rabeprazole bid , 1000 mg amoxicillin bid , 100 mg bismuth pectin qid , and 500 mg levofloxacin qd ); group B (n = 72) received the sequential therapy (20 mg omeprazole bid , 1000 mg amoxicillin bid , in 5 d, followed by 20 mg omeprazole bid , 500 mg tinidazole bid , 500 mg clarithromycin bid , for another 5 d); group C (n = 71) received a standard 1-wk triple therapy (20 mg omeprazole bid , 1000 mg amoxicillin bid , 500 mg clarithromycin bid ). After all these treatments, 20 mg omeprazole bid was administrated for 3 wk. H. pylori status was assessed by histology, 13C-urea breath test and rapid urease test at baseline and 4-6 wk after completion of treatment. Ulcer cicatrization was assessed by gastroscopy. χ 2 test (P < 0.05) was used to compare the eradication rates and ulcer cicatrisation rates among the three groups. RESULTS: The eradication rate was 83.33% (60/72) in group A, 88.89% (64/72) in group B, and 80.56% (58/71) in group C. The ulcer cicatrisation rate was 86.44% (51/59) in group A, 90.16% (55/61) in group B, and 84.91% (45/53) in group C. The sequential therapy yielded a higher eradication rate and ulcer cicatrisation rate than the standard triple and bismuth pectin quadruple therapies. Statistically, the eradication rate of group B was significantly different from groups A and C (P < 0.05), but the difference of ulcer cicatrisation rate and side effects was not statistically significant among the three groups (P > 0.05). The three protocols were generally well tolerated. CONCLUSION: The sequential therapy has achieved a significantly higher eradication rate, and is a more suitable first-line alternative protocol for anti-H. pylori infection compared with the standard triple and bismuth pectin quadruple therapies.展开更多
Modified pectin cross-linked with adipic acid, was synthesized and used for heavy metal removal from wastewater. SEM and FTIR were used to investigate its structure and morphology. The modified pectin had a rough, por...Modified pectin cross-linked with adipic acid, was synthesized and used for heavy metal removal from wastewater. SEM and FTIR were used to investigate its structure and morphology. The modified pectin had a rough, porous phase covered with carboxy groups, resulting a high adsorption capacity. And at the room temperature, the saturated loading capacity for Pb^2＋, Cu^2＋ and Zn^2＋ reached 1.82 retool/g, 1.794 mmol/g and 0.964 retool/g, respectively. The results proved its potential application to remove of the heavy metal.展开更多
The aim of this study was to investigate the effect of high-pressure homogenization on the droplet size and physical stability of different formulations of pectin–zein stabilized rice bran oil emulsions. The obtained...The aim of this study was to investigate the effect of high-pressure homogenization on the droplet size and physical stability of different formulations of pectin–zein stabilized rice bran oil emulsions. The obtained emulsions, both before and after passing through highpressure homogenizer, were subjected to stability test under environmental stress conditions,that is, temperature cycling at 4 °C/40 °C for 6 cycles and centrifugal test at 3000 rpm for 10 min. Applying high-pressure homogenization after mechanical homogenization caused only a small additional decrease in emulsion droplet size. The droplet size of emulsions was influenced by the type of pectin used;emulsions using high methoxy pectin(HMP) were smaller than that using low methoxy pectin(LMP). This is due to a greater emulsifying property of HMP than LMP. The emulsions stabilized by HMP–zein showed good physical stability with lower percent creaming index than those using LMP, both before and after passing through high-pressure homogenizer. The stability of emulsions after passing through high-pressure homogenizer was slightly higher when using higher zein concentration, resulting from stronger pectin–zein complexes that could rearrange and adsorb onto the emulsion droplets.展开更多
AIM： To study isolation and chemical characterization of pectin derived from the common cranberry Vaccin/um oxycoccos L. （oxycoccusan OP） and the testing of its preventive effect on experimental colitis. METHODS： ...AIM： To study isolation and chemical characterization of pectin derived from the common cranberry Vaccin/um oxycoccos L. （oxycoccusan OP） and the testing of its preventive effect on experimental colitis. METHODS： Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid. RESULTS： In the mice treated with OP, colonic macroscopic scores （1.1 ± 0.4 vs 2.7, P 〈 0.01） and the total square area of damage （10 ± 2 vs 21 ± 7, P 〈 0.01） were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons （42 ± 11 vs 112 ± 40, P 〈 0.01） and enhance the amount of mucus of colitis mice （0.9 ± 0.1 vs 0.4 ± 0.1, P 〈 0.01）. The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice （3.6 ± 0.7 vs 5.1 ± 0.8, P 〈 0.01）. OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability （161 ± 34 vs 241 ± 21, P 〈 0.01）. Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP （141 ± 50 vs 235 ± 37, P 〈 0.05）. CONCLUSION： Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.展开更多
The gastrointestinal tract of livestock and poultry is prone to challenge by feedborne antigens,pathogens,and other stress factors in the farm environment.Excessive physiological inflammation and oxidative stress that...The gastrointestinal tract of livestock and poultry is prone to challenge by feedborne antigens,pathogens,and other stress factors in the farm environment.Excessive physiological inflammation and oxidative stress that arises firstly disrupts the intestinal epithelial barrier followed by other components of the gastrointestinal tract.In the present review,the interrelationship between intestinal barrier inflammation and oxidative stress that contributes to the pathogenesis of inflammatory bowel disease was described.Further,the role of naturally existing immunomodulatory nutrients such as the omega-3 polyunsaturated fatty acids,citrus pectin,and milk-derived exosomes in preventing intestinal barrier inflammation was discussed.Based on the existing evidence,the possible molecular mechanism of these bioactive nutrients in the intestinal barrier was outlined for application in animal diets.展开更多
Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this...Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this study,pigs were fed a corn-soybean meal-based diet supplemented with either 5%microcrystalline cellulose(MCC)or 5%pectin for 3 weeks,to investigate the metabolites and anti-inflammatory properties of the jejunum.Result The results showed that dietary pectin supplementation improved intestinal integrity(Claudin-1,Occludin)and inflammatory response[interleukin(IL)-10],and the expression of proinflammatory cytokines(IL-1β,IL-6,IL-8,TNF-α)was down-regulated in the jejunum.Moreover,pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in piglets.Pectin specifically increased the abundance of Lactococcus,Enterococcus,and the microbiota-derived metabolites(skatole(ST),3-indoleacetic acid(IAA),3-indolepropionic acid(IPA),5-hydroxyindole-3-acetic acid(HIAA),and tryptamine(Tpm)),which activated the aryl hydrocarbon receptor(AhR)pathway.AhR activation modulates IL-22 and its downstream pathways.Correlation analysis revealed the potential relationship between metabolites and intestinal morphology,intestinal gene expression,and cytokine levels.Conclusion In conclusion,these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway,which is activated through tryptophan metabolites.展开更多
Cell wall polysaccharides play a vital role in binding with toxic metals such as copper(Cu)ions.However, it is still unclear whether the major binding site of Cu in the cell wall varies with different degrees of Cu st...Cell wall polysaccharides play a vital role in binding with toxic metals such as copper(Cu)ions.However, it is still unclear whether the major binding site of Cu in the cell wall varies with different degrees of Cu stresses.Moreover, the contribution of each cell wall polysaccharide fraction to Cu sequestration with different degrees of Cu stresses also remains to be verified.The distribution of Cu in cell wall polysaccharide fractions of castor(Ricinus communis L.) root was investigated with various Cu concentrations in the hydroponic experiment.The results showed that the hemicellulose1(HC1) fraction fixed 44.9%–67.8% of the total cell wall Cu under Cu stress.In addition, the pectin fraction and hemicelluloses2(HC2) fraction also contributed to the Cu binding in root cell wall,accounting for 11.0%–25.9% and 14.1%–26.6% of the total cell wall Cu under Cu treatments, respectively.When the Cu levels were ≤ 25 μmol/L, pectin and HC2 contributed equally to Cu storage in root cell wall.However, when the Cu level was higher than 25 μmol/L, the ability of the pectin to bind Cu was easy to reach saturation.Much more Cu ions were bound on HC1 and HC2 fractions, and the HC2 played a much more important role in Cu binding than pectin.Combining fourier transform infrared(FT-IR) and twodimensional correlation analysis(2 D-COS) techniques, the hemicellulose components were showed not only to accumulate most of Cu in cell wall, but also respond fastest to Cu stress.展开更多
基金Supported by National Natural Science Foundation of China(31501487)
文摘Dough preparation and performance are two critical factors influencing the final quality of wheat products. The influence of high and low methoxyl pectins on empirical and dynamic rheological properties of dough and Chinese steamed bread(CSB)quality were investigated. Different concentrations of high methoxyl apple pectin(HMAP), low methoxyl apple pectin(LMAP),and amidation apple pectin(ALMAP) were tested. Results from dynamic and empirical rheological tests indicated that all concentrations of pectins tested(0.2%, 0.6%, and 1%) negatively affected the gluten network. The low methoxyl pectins, LMAP and ALMAP, which had higher anionic densities, resulted in a pronounced weakening of the dough. Meanwhile, dough fermentation properties improved in the presence of appropriate pectins concentrations, and higher maximum dough height, stability of dough pore space, and gas retention were recorded. HMAP was the pectin most effective in influencing dough fermentation properties at all tested concentrations. Regarding CSB quality, textural properties, specific volume, moisture content, and water-holding capacity were analyzed. Generally, the textural properties of CSB were improved, including improved springiness and decreased hardness and chewiness, when 0.2%–0.6% HMAP or LMAP was used. The specific volume of CSB was increased by adding 0.2%–1% HMAP,0.6%–1% LMAP, or 0.2%–0.6% ALMAP. Moreover, CSB moisture loss was progressively reduced in the presence of different pectins at all tested concentrations during storage. In conclusion, pectins, especially HMAP, are good additives for improving the fermentation properties of dough and overall quality of CSB.
文摘Plasmodesmata(PD)create symplasmic continuity in plant tissues by connecting the cytoplasm of neighboring cells.Molecular movement through PD is important for many processes,including organ development,pathogen defense,environmental acclimation,and nutrient allocation.Elucidating the kinetics of PD transport and its regulation is essential for understanding these processes.
基金the NSF (MCB-1615387)a Yale University Brown Fellowship for funding
文摘Pectins are complex cell wall polysaccharides important for many aspects of plant development. Recent studies have discovered extensive physical interactions between pectins and other cell wall components,implicating pectins in new molecular functions. Pectins are often localized in spatially-restricted patterns, and some of these non-uniform pectin distributions contribute to multiple aspects of plant development, including the morphogenesis of cells and organs. Furthermore, a growing number of mutants affecting cell wall composi- tion have begun to reveal the distinct contributions of different pectins to plant development. This review discusses the interactions of pectins with other cell wall components, the functions of pectins in controlling cellular morphology, and how non-uniform pectin composition can be an important determinant of developmental processes.
文摘Abstract: Arabinogalactan proteins (AGPs) and pectins were detected in the floral buds of cucumber (Cucumis sativus L.) during its sex determination using the following monoclonal antibodies: MAC 207 (recognizes AGP epitopes); JIM 8 (recognizes a subset of AGP epitopes); and JIM 5 and JIM 7 (epitopes of pectins esterified to various degrees). In the stem apex meristem (SAM) of the cucumber, epitopes of MAC 207, JIM 7, and JIM 5 were localized in the cells from second to third peripheral layers when the sex organ primodium began to differentiate; epitopes of MAC 207 and JIM 5 were also detected in the ragged edge cells. A very dense labeling signal with MAC 207 was observed in the carpel and pistil primodium. The AGP epitopes recognized by JIM 8 were localized in the anther of the male flower and the anther-like portion of the stagnant stamen of the female flower. This suggests that the AGPs and pectins in the SAM of the cucumber are closely associated with the differentiation of the SAM, from meristematic cells to floral primodium. The subset of AGPs recognized by JIM 8 may play an important role in stamen formation.
基金supported by grants from the National Key Research and Development Program of China(2021YFD2200502_3)the National Natural Science Foundation of China(32400247 and 32401906)the CAS Project for Young Scientists in Basic Research(YSBR-119)。
文摘The plant cell wall is an extremely complicated natural nanoscale structure composed of cellulose microfibrils embedded in a matrix of noncellulosic polysaccharides,further reinforced by the phenolic compound lignins in some cell types.Such a network formed by the interactions of multiscale polymers actually reflects functional form of the cell wall to meet the requirements of plant cell functionalization.Therefore,how plants assemble cell wall functional structure is fundamental in plant biology and critical for crop trait formation and domestication as well.Due to the lack of effective analytical techniques to characterize this fundamental but complex network,it remains difficult to establish direct links between cell-wall genes and phenotypes.The roles of plant cell walls are often underestimated as indirect.Over the past decades,many genes involved in cell wall biosynthesis,modification,and remodeling have been identified.The application of a variety of state-of-the-art techniques has made it possible to reveal the fine cell wall networks and polymer interactions.Hence,many exciting advances in cell wall biology have been achieved in recent years.This review provides an updated overview of the mechanistic and conceptual insights in cell wall functionality,and prospects the opportunities and challenges in this field.
基金supported by the grants of the National Natural Science Foundation of China(Grant No.82474070)Jilin Science&Technology Development Plan(Grant No.20230204003YY).
文摘Biomacromolecules derived from plant-based traditional Chinese medicines play a pivotal role in natural drug research.Ginseng,the root of Panax ginseng C.A.Meyer,has attracted significant attention due to its diverse pharmacological activities and broad therapeutic applications.This review focuses on specific active macromolecules obtained from ginseng,including pectin,exosomes,proteins,and dietary fibers.These components possess unique structural characteristics and biological activities that offer novel insights into the multifaceted applications of ginseng.To systematically assess this field,we reviewed literature published over the past 60 years and identified 119 relevant studies investigating the structural composition,pharmacological activity,and potential applications of P.ginseng biomacromolecules.By highlighting their crucial role in promoting health and enhancing disease resistance,this review synthesizes the latest research findings on ginseng’s pharmacological effects,providing new perspectives and strong theoretical support for clinical drug development.
文摘Hexavalent chromium,when present in high concentrations,causes a serious threat to the ecosystem.This can lead to severe ecological damage and persistent environmental issues,making it a significant concern for long-term sustainability.Thus,there is a strong need for high-performing adsorbents to remove high concentrations of Cr(VI)from the environment.In the present study,Citrus Limetta peels were utilised to produce pristine biochar,which was treated with iron oxides to generate magnetic biochar and modified with chitosan,sodium alginate,and pectin to produce respective modified biochar.Among all five biochars,Chitosan-modified biochar(CMBC)displayed the highest removal efficiency towards Cr(VI)from water with a maximum adsorption capacity of 152.44 mg/g and a removal capacity of 76.22%.Furthermore,adsorption kinetics indicates that the adsorption process is a pseudo-second order-kinetic model with R^(2)and qe of 0.99 and 99 mg/g,respectively.The Langmuir isotherm best describes the adsorption process.After five regenerative cycles,the removal efficiency was maintained at up to 71.80%.This work highlights the remarkable potential of engineered biochar in wastewater treatment.
基金supported by the National Natural Science Fund(31601395)Central Guidance on Local Science and Technology Development Fund of Guizhou Province([2023]016)+1 种基金China National Center for Food Safety Risk Assessment(2018K01-20171211)Lueyang Black-Bone Chicken Industry Development Research Institute(WJYJY-2021-9)。
文摘Tropomyosin(TM)is the predominant allergenic protein in shrimp,which has induced IgE-mediated food allergy reactions.In this study,Lit v 1 was purified from Penaeus vannamei muscles,which were glyco sylated by pectic oligosaccharides.The results showed that di-galacturonic acid(DGA)and galacturonic acid(GA)induced the unfolding of the primary protein structure of TM,and changedα-helical structure,and IgE binding capacity.In addition,compared with TM-sensitized BALB/c mice,GA-modified TM(GA-TM)and DGA-modified TM(DGA-TM)were insufficient to stimulate sensitization,and significantly reduced the hypersecretion of IgE,IgG1,HIS,and IL-4,up-regulated IgG2a and IFN-y levels to improve imbalanced Th1/Th2,Treg/Th17 immunity,and promoted mRNA expression of tight junction proteins.Together,this study confirmed that glycosylation modification alleviated sensitization by altering TM structure,reducing IgE binding allergic inflammatory response,and regulating cytokine immune balance.Overall,these results indicated that glycosylation modification was a promising method for decreasing the allergenic reactivity of allergic proteins.
文摘Pectin is a natural polysaccharide with a complex structure consisting of linear and branched regions rich in galacturonic acid.The growing interest in orange peel pectin can be attributed to its abundant supply.According to statistics,about 10 million tons of orange peel waste are produced worldwide each year.Traditionally,the extraction and utilization of pectin have focused on its gelling,thickening,and stabilizing properties in food.However,as more and more research teams have found that pectin has good biocompatibility,biodegradability and easy chemical modification,its potential in drug delivery systems,tissue engineering,and wound healing is gradually being explored.This review focuses on orange peel pectin polysaccharides and discusses its traditional and modern extraction techniques,especially the advanced method of subcritical water extraction.This study also outlines the structural modifications of pectin such as methylation and acetylation,and introduces its antioxidant and anticancer biological activities and their emerging roles in the development of advanced biomaterials such as bone tissue engineering and fibre pad dressings.
基金Supported by the Key Project of the National Twelfth-Five Year Research Program of China(2012BAD31B03)Guangdong Province Science and Technology Project(2011B010100041)~~
文摘In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase （PPO） and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO.
基金Natural Science Foundation of Ningxia Hui Autonomous Region(B1007)~~
文摘The changes of physiological and biochemical indices in jujube fruits during the late development were investigated from 6-year-old jujube trees （Zizyphus jujuba Mill. cv. Lingwuchangzao）. The results showed that the flesh firmness decreased slowly from white-green stage to full-red stage, being significantly related with the developmental maturity of jujube fruits negatively, the correlation coefficient reached -0.980 3^＊＊. The contents of ascorbic acid and titratable acid in jujube fruits were significantly related with the developmental process of jujube fruits negatively or positively, the correlation coef- ficients were -0. 973 1^＊＊and ＋ 0. 974 6^ ＊ ＊ , respectively. The contents of soluble solids, total sugar, and sucrose increased with jujube ripening, while the relative sweetness of jujube fruits showed the same variation pattern, the correlation coefficients were 0. 996 6 ^＊ ＊ , 0. 988 0^＊＊ , and 0. 982 8 ^＊ ＊ , respectively. Before white-green stage during fruit development, the accumulation of monosaccharide was predominant in jujube fruits, following a fast accumulation of sucrose, indicating that the main component of sugars is sucrose at the crisp-ripe stage. Furthermore, the starch content of the flesh reached the peak at about thirty percentage of jujube maturity, being 51,54 mg/100 g.FW. The respiratory rates varied between 10 mg/（ kg.h） and CO2 26 mg/（ kg.h） after fruit turning red and before softening, indicating a non-climacteric respiratory type.
基金Shanghai Municipal Committee of Sciencc and Tcchnology (Grant No.024319114).
文摘We studied the effect of two independent variables, the pectin/calcium chloride weight ratio and the overall matrix weight in HPMC/pectin/calcium matrix tablet, on the release of indomethacin. A two-factor 5-level central composite experimental design was employed. Responses of the Peppas correlation parameters n and K and the 10% release time （T0.1） were optimized by response surface methodology. Significant effect of the independent variables on the biphasic release parameters, n and K, was observed. N, K and T0.1 were well fitted with the second-order quadratic equations rather than linear equations. Moreover, the mathematic fitting and the response surfaces showed significant cross-interaction between the pectin/calcium chloride ratio and the overall matrix weight. The optimal formulation with larger n, longer T0.1 and smaller K consisted of medium pectin/calcium chloride ratio around 1.0 and medium matrix weight around 200 mg. Validation studies on the optimal formulations showed good predictability of the n, K and T0.1 values with biases within the range of-7.33% and 6.26%. Our results support that central composite design can be used to optimize drug release from HPMC/pectin/calcium matrix tablet with high predictability.
文摘AIM: To discuss the expression of glactin-3 in liver metastasis of colon cancer and its inhibition by modi- fied citrus pectin (MCP) in mice. METHODS: Seventy-five Balb/c mice were randomly di- vided into negative control group (n = 15), positive con- trol group (n = 15), low MCP concentration group (n = 15), middle MCP concentration group (n = 15) and high MCP concentration group (n = 15). CT26 colon cancer cells were injected into the subcapsule of mouse spleen in positive control group, low, middle and high MCP concentrations groups, except in negative control, to set up a colon cancer liver metastasis model. The concen- tration of MCP in drinking water was 0.0%, 0.0%, 1.0%, 2.5% and 5.0% (wt/vol), respectively. Liver metastasis of colon cancer was observed after 3 wk. Enzyme-linked immunosorbent assay (ELISA) was used to detect the concentration of galectin-3 in serum. Expression of ga- lectin-3 in liver metastasis was detected by immunohis- tochemistry. RESULTS: Except for the negative group, the percent- age of liver metastasis in the other 4 groups was 100%, 80%, 73.3% and 60%, respectively. The number of liver metastases in high MCP concentration group was significantly less than that in positive control group (P = 0.008). Except for the negative group, the median volume of implanted spleen tumor in the other 4 groups was 1.51 cm3, 0.93 cm3, 0.77 cm3 and 0.70 cm3, respec- tively. The volume of implanted tumor in middle and high MCP concentration groups was significantly smaller than that in positive control group (P = 0.019; P = 0.003). The concentration of serum galectin-3 in positive control and MCP treatment groups was significantly higher than that in the negative control group. However, there was no significant difference between them. Except for the negative control group, the expression of galectin-3 in liver metastases of the other 4 groups showed no sig- nificant difference. CONCLUSION: Expression of galetin-3 increases sig- nificantly in liver metastasis of colon cancer, which can be effectively inhibited by MCP.
文摘AIM: To compare the effectiveness of standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori (H. pylori ) eradication in a randomized, double-blinded, comparative clinical trial in China. METHODS: A total of 215 H. pylori -positive patients were enrolled in the study and randomly allocated into three groups: group A (n = 72) received a 10-d bismuth pectin quadruple therapy (20 mg rabeprazole bid , 1000 mg amoxicillin bid , 100 mg bismuth pectin qid , and 500 mg levofloxacin qd ); group B (n = 72) received the sequential therapy (20 mg omeprazole bid , 1000 mg amoxicillin bid , in 5 d, followed by 20 mg omeprazole bid , 500 mg tinidazole bid , 500 mg clarithromycin bid , for another 5 d); group C (n = 71) received a standard 1-wk triple therapy (20 mg omeprazole bid , 1000 mg amoxicillin bid , 500 mg clarithromycin bid ). After all these treatments, 20 mg omeprazole bid was administrated for 3 wk. H. pylori status was assessed by histology, 13C-urea breath test and rapid urease test at baseline and 4-6 wk after completion of treatment. Ulcer cicatrization was assessed by gastroscopy. χ 2 test (P < 0.05) was used to compare the eradication rates and ulcer cicatrisation rates among the three groups. RESULTS: The eradication rate was 83.33% (60/72) in group A, 88.89% (64/72) in group B, and 80.56% (58/71) in group C. The ulcer cicatrisation rate was 86.44% (51/59) in group A, 90.16% (55/61) in group B, and 84.91% (45/53) in group C. The sequential therapy yielded a higher eradication rate and ulcer cicatrisation rate than the standard triple and bismuth pectin quadruple therapies. Statistically, the eradication rate of group B was significantly different from groups A and C (P < 0.05), but the difference of ulcer cicatrisation rate and side effects was not statistically significant among the three groups (P > 0.05). The three protocols were generally well tolerated. CONCLUSION: The sequential therapy has achieved a significantly higher eradication rate, and is a more suitable first-line alternative protocol for anti-H. pylori infection compared with the standard triple and bismuth pectin quadruple therapies.
文摘Modified pectin cross-linked with adipic acid, was synthesized and used for heavy metal removal from wastewater. SEM and FTIR were used to investigate its structure and morphology. The modified pectin had a rough, porous phase covered with carboxy groups, resulting a high adsorption capacity. And at the room temperature, the saturated loading capacity for Pb^2＋, Cu^2＋ and Zn^2＋ reached 1.82 retool/g, 1.794 mmol/g and 0.964 retool/g, respectively. The results proved its potential application to remove of the heavy metal.
基金financially supported by the Research and Development Institute, Silpakorn University
文摘The aim of this study was to investigate the effect of high-pressure homogenization on the droplet size and physical stability of different formulations of pectin–zein stabilized rice bran oil emulsions. The obtained emulsions, both before and after passing through highpressure homogenizer, were subjected to stability test under environmental stress conditions,that is, temperature cycling at 4 °C/40 °C for 6 cycles and centrifugal test at 3000 rpm for 10 min. Applying high-pressure homogenization after mechanical homogenization caused only a small additional decrease in emulsion droplet size. The droplet size of emulsions was influenced by the type of pectin used;emulsions using high methoxy pectin(HMP) were smaller than that using low methoxy pectin(LMP). This is due to a greater emulsifying property of HMP than LMP. The emulsions stabilized by HMP–zein showed good physical stability with lower percent creaming index than those using LMP, both before and after passing through high-pressure homogenizer. The stability of emulsions after passing through high-pressure homogenizer was slightly higher when using higher zein concentration, resulting from stronger pectin–zein complexes that could rearrange and adsorb onto the emulsion droplets.
基金the Program of Presidium of the Russian Acad.Sci. <>, the Russian Fund forBasic Research, No. 06-04-48079 the Program for LeadingScientific Schools, No. 5796.2006.4
文摘AIM： To study isolation and chemical characterization of pectin derived from the common cranberry Vaccin/um oxycoccos L. （oxycoccusan OP） and the testing of its preventive effect on experimental colitis. METHODS： Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid. RESULTS： In the mice treated with OP, colonic macroscopic scores （1.1 ± 0.4 vs 2.7, P 〈 0.01） and the total square area of damage （10 ± 2 vs 21 ± 7, P 〈 0.01） were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons （42 ± 11 vs 112 ± 40, P 〈 0.01） and enhance the amount of mucus of colitis mice （0.9 ± 0.1 vs 0.4 ± 0.1, P 〈 0.01）. The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice （3.6 ± 0.7 vs 5.1 ± 0.8, P 〈 0.01）. OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability （161 ± 34 vs 241 ± 21, P 〈 0.01）. Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP （141 ± 50 vs 235 ± 37, P 〈 0.05）. CONCLUSION： Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.
基金a European Joint Doctorate Degree programme in Molecular Animal Nutrition(MANNA)between University of Milan(Italy)and University of Veterinary Medicine and Pharmacy in Kosice(Slovakia)funding from the European Union’s Horizon 2020 programme under the Marie Slodowska-Curie Grant agreement No 765423.
文摘The gastrointestinal tract of livestock and poultry is prone to challenge by feedborne antigens,pathogens,and other stress factors in the farm environment.Excessive physiological inflammation and oxidative stress that arises firstly disrupts the intestinal epithelial barrier followed by other components of the gastrointestinal tract.In the present review,the interrelationship between intestinal barrier inflammation and oxidative stress that contributes to the pathogenesis of inflammatory bowel disease was described.Further,the role of naturally existing immunomodulatory nutrients such as the omega-3 polyunsaturated fatty acids,citrus pectin,and milk-derived exosomes in preventing intestinal barrier inflammation was discussed.Based on the existing evidence,the possible molecular mechanism of these bioactive nutrients in the intestinal barrier was outlined for application in animal diets.
基金supported by National Natural Science Foundation of China(NSFC)(31802072)China Scholarship Council(CSC NO.202103250006)+1 种基金the Central Public-interest Scientific Institution Basal Research Fund(No.Y2022GH02&PJ01618301)State Key Laboratory of Animal Nutrition(2004DA125184G2102)。
文摘Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this study,pigs were fed a corn-soybean meal-based diet supplemented with either 5%microcrystalline cellulose(MCC)or 5%pectin for 3 weeks,to investigate the metabolites and anti-inflammatory properties of the jejunum.Result The results showed that dietary pectin supplementation improved intestinal integrity(Claudin-1,Occludin)and inflammatory response[interleukin(IL)-10],and the expression of proinflammatory cytokines(IL-1β,IL-6,IL-8,TNF-α)was down-regulated in the jejunum.Moreover,pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in piglets.Pectin specifically increased the abundance of Lactococcus,Enterococcus,and the microbiota-derived metabolites(skatole(ST),3-indoleacetic acid(IAA),3-indolepropionic acid(IPA),5-hydroxyindole-3-acetic acid(HIAA),and tryptamine(Tpm)),which activated the aryl hydrocarbon receptor(AhR)pathway.AhR activation modulates IL-22 and its downstream pathways.Correlation analysis revealed the potential relationship between metabolites and intestinal morphology,intestinal gene expression,and cytokine levels.Conclusion In conclusion,these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway,which is activated through tryptophan metabolites.
基金supported by the Natural Science Foundation of China (No.41371470)the National Key Technology Support Program (No.2015BAD05B02).
文摘Cell wall polysaccharides play a vital role in binding with toxic metals such as copper(Cu)ions.However, it is still unclear whether the major binding site of Cu in the cell wall varies with different degrees of Cu stresses.Moreover, the contribution of each cell wall polysaccharide fraction to Cu sequestration with different degrees of Cu stresses also remains to be verified.The distribution of Cu in cell wall polysaccharide fractions of castor(Ricinus communis L.) root was investigated with various Cu concentrations in the hydroponic experiment.The results showed that the hemicellulose1(HC1) fraction fixed 44.9%–67.8% of the total cell wall Cu under Cu stress.In addition, the pectin fraction and hemicelluloses2(HC2) fraction also contributed to the Cu binding in root cell wall,accounting for 11.0%–25.9% and 14.1%–26.6% of the total cell wall Cu under Cu treatments, respectively.When the Cu levels were ≤ 25 μmol/L, pectin and HC2 contributed equally to Cu storage in root cell wall.However, when the Cu level was higher than 25 μmol/L, the ability of the pectin to bind Cu was easy to reach saturation.Much more Cu ions were bound on HC1 and HC2 fractions, and the HC2 played a much more important role in Cu binding than pectin.Combining fourier transform infrared(FT-IR) and twodimensional correlation analysis(2 D-COS) techniques, the hemicellulose components were showed not only to accumulate most of Cu in cell wall, but also respond fastest to Cu stress.
