Pectin Structure Research Articles

Contrasting Cd accumulation of Arabidopsis halleri populations: a role for (1→4)-β-galactan in pectin

Cadmium (Cd) accumulation is highly variable among Arabidopsis halleri populations. To identify cell wall (CW) components that contribute to the contrasting Cd accumulation between PL22-H (Cd-hyperaccumulator) and I16-E (Cd-excluder), Cd absorption capacity of CW polysaccharides, CW mono- and poly- saccharides contents and CW glycan profiles were compared between these two populations. PL22-H pectin contained 3-fold higher Cd concentration than I16-E pectin in roots, and (1→4)-β-galactan pectic epitope showed the biggest difference between PL22-H and I16-E. CW-related differentially expressed genes (DEGs) between PL22-H and I16-E were identified and corresponding A. thaliana mutants were phenotyped for Cd tolerance and accumulation. A higher Cd translocation was observed in GALACTAN SYNTHASE1 A. thaliana knockout and overexpressor mutants, which both showed a lengthening of the RG-I sidechains after Cd treatment, contrary to the wild-type. Overall, our results support an indirect role for (1→4)-β-galactan in Cd translocation, possibly by a joint effect of regulating the length of RG-I sidechains, the pectin structure and interactions between polysaccharides in the CW. The characterization of other CW-related DEGs between I16-E and PL22-H selected allowed to identify a possible role in Zn translocation for BIIDXI and LEUNIG-HOMOLOG genes, which are both involved in pectin modification.

Extraction of Pectin from Passion Fruit Peel: Composition, Structural Characterization and Emulsion Stability.

Extraction methods directly affect pectin extraction yield and physicochemical and structural characteristics. The effects of acid extraction (AE), ultrasonic-assisted acid extraction (UA), steam explosion pretreatment combined with acid extraction (SEA) and ultrasonic-assisted SEA (USEA) on the yield, structure, and properties of passion fruit pectin were studied. The pectin yield of UA was 6.5%, equivalent to that of AE at 60 min (5.3%), but the emulsion stability of UA pectin was poor. The pectin obtained by USEA improved emulsion stability. Compared with UA, it had higher protein content (0.62%), rhamnogalacturonan I (18.44%) and lower molecular weight (0.72 × 105 Da). In addition, SEA and USEA had high pectin extraction yields (9.9% and 10.7%) and the pectin obtained from them had lower degrees of esterification (59.3% and 68.5%), but poor thermal stability. The results showed that ultrasonic-assisted steam explosion pretreatment combined with acid extraction is a high-efficiency and high-yield method. This method obtains pectin with good emulsifying stability from passion fruit peel.

Investigation of capacitors and electrical circuit elements performance of magnetic biocomposites prepared by using the hemp biomass

Hemp biomass (HB) was brought into activated hemp biomass (AHB) by chemical technique and all samples were obtained by doping different nanoparticles. Structural, dielectric and magnetic characterizations for all samples were performed by using the XRD, FTIR, SEM, EDX, LCR Meter and PPMS at room temperature. The characteristics of both hemp biomass and nanoparticles in the structures of these samples were examined in detail. In addition to HB and AHB samples, the contribution of lignin and pectin characteristic bands to conductivity was investigated in AHB samples doped with Fe3O4, MgFe2O4 and SrFe2O4 nanoparticles. It has been determined that homogeneously dispersed nanoparticles contribute to surface area, crystallization and conductivity and these samples are technological products. It was determined that the samples could be used as batteries, and two electrical circuits simultaneously connected to the lignin and pectin structures of the activated hemp biomass (AHB) doped with different types of nanoparticles were obtained from the Smith-Chart diagram.

Yeast fermentation of apple and grape pomaces affects subsequent aqueous pectin extraction: Composition, structure, functional and antioxidant properties of pectins

Fruit waste valorisation to generate value-added pectin products is an active research area. In this study, pectin products from unfermented apple/grape pomace (AP/GP) and from fermented apple/grape pomace (FAP/FGP) were prepared via extraction with aqueous citric acid at 60 °C. Fermented apple/grape pomace was produced via yeast fermentation. Compared with GP, AP had a higher pectin yield, GalA and protein contents, amounts of HG and RG-I, Mw, branching degree and size of neutral side chains, but lower degree of methoxylation (DM), linearity of pectin and phenolic/anthocyanin content. AP, FAP and GP had a DM higher than 50%, whilst FGP had a DM lower than 50%. Fermentation decreased pectin's yield, DM and contents of phenolics and anthocyanins, while altering significantly the monosaccharide profiles of the pectins. Fermentation yielded pectins with smoother surfaces and more amorphous structures. Fermentation of apple pomace decreased HG by 58% and caused a 2.39-fold increase in RG-I, whereas, fermentation of grape pomace decreased HG and increased RG-I to a lesser extent. All these fermentation-induced changes caused differences in shear-thinning behavior, thermal stability, viscoelasticity and antioxidant activities between AP/GP and FAP/FGP. FAP and FGP aqueous dispersions (2.0–5.0%) had lower viscosities than AP and GP dispersions. All pectin samples can be used as emulsifiers, gelling agents and rheology modifiers. FAP and FGP were the most and least effective emulsifiers, respectively, at concentrations of 1.0–2.0% w/v. All pectin samples possessed significant antioxidant activities. GP had the highest antioxidant capacity (at 20 or 30 mg/mL exhibiting comparable activity to vitamin C).

Modulation of the Gut Microbiota Structure and Function by Two Structurally Different Lemon Pectins

Pectins are plant polysaccharides consumed as part of a diet containing fruits and vegetables. Inside the gastrointestinal tract, pectin cannot be metabolized by the mammalian cells but is fermented by the gut microbiota in the colon with the subsequent release of end products including short-chain fatty acids (SCFA). The prebiotic effects of pectin have been previously evaluated but reports are inconsistent, most likely due to differences in the pectin chemical structure which can vary by molecular weight (MW) and degree of esterification (DE). Here, the effects of two different MW lemon pectins with varying DEs on the gut microbiota of two donors were evaluated in vitro. The results demonstrated that low MW, high DE lemon pectin (LMW-HDE) altered community structure in a donor-dependent manner, whereas high MW, low DE lemon pectin (HMW-LDE) increased taxa within Lachnospiraceae in both donors. LMW-HDE and HMW-LDE lemon pectins both increased total SCFAs (1.49- and 1.46-fold, respectively) and increased acetic acid by 1.64-fold. Additionally, LMW-HDE lemon pectin led to an average 1.41-fold increase in butanoic acid. Together, these data provide valuable information linking chemical structure of pectin to its effect on the gut microbiota structure and function, which is important to understanding its prebiotic potential.

Production and Characterisation of Pectin from Cocoa Bean Shells

Cocoa bean shells constitute the major waste generated from the industrial processing of cocoa beans. The shells contain about 9% of pectin and extracting it would be of economic and ecological importance. However, limited knowledge on the characteristics of the pectin from cocoa bean shells and the extraction conditions, which would yield pectin of good quality and sufficient quantity, restrict the possible use of the shells as a source of commercial pectin. The objective of this study was to extract and characterise pectin from cocoa bean shells, with focus on finding the optimum extraction conditions. The conventional hot dilute acid extraction method was used. 12 M hydrochloric acid was used to acidify water to pH 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0. Extractions were carried out at temperatures of 60, 70, and 80 °C, for different times of 0.5, 1, and 2 h. The effects of each of the conditions on yield and other properties of pectin were evaluated. Depending on the conditions under which cocoa bean shells were treated, both high methoxyl and low methoxyl pectins were extracted. At the optimum conditions of pH 3.5, extraction time of 2 h and 80 °C extraction temperature, high methoxyl pectin was obtained. The yield was 4.7%, the degree of esterification was 68.9% and the anhydrouronic acid content was 71.2%. While the methoxyl content was 8.6%, the equivalent mass was found to be 805.8 g/eq. Moisture and ash contents were 6.7 and 10.3%, respectively, and the pH of the pectin hydrocolloid was 3.7. Fourier Transform Infrared (FT-IR) spectra confirmed the presence of functional groups found in the pectin structure. The intrinsic viscosity varied between 0.075–0.088 m3/kg and the molecular mass ranged from 23,470 - 42,384 g/mol. The results revealed that the shells are a viable source for commercial pectin, while necessary investigations focusing on the gelling, thickening, emulsifying, texturing, and stabilising potentials of the pectin from cocoa bean shells would inform of the areas of application

The structure-function relationships of pectins separated from three citrus parts: Flavedo, albedo, and pomace

Citrus pectin is the main source of commercial pectin, which is widely used as an emulsifying and gelling agent. However, there is no information on the chemical structure of pectins from different citrus parts, and their functional properties are unclear. In this study, pectins from flavedo, albedo, and pomace were separated by a fractionated processing method, and their chemical structures and emulsifying and gelling properties were investigated to clarify the structure-function relationship. Interestingly, for both pomelo and grapefruit, pectins from different parts showed similar principles; that is, pomace pectin and albedo pectin showed the strongest emulsifying and gelling properties, respectively. Pomace pectin had a high degree of esterification (DE; 86.9%) and medium molecular weight (Mw; 177.7 kDa), and the most compact conformation (i.e., lowest Dmax and Rg values). Thus, it could form a thick layer at the oil-water interface and improve the viscosity of the continuous phase, thereby stabilizing the emulsion. Albedo pectin had the highest DE (89.8%), Mw (258.1 kDa), and proportion of HG region (87.7%); therefore, it gelled rapidly and had the tightest network structure. The findings provide insight into the structure-function relationship of pectin from different citrus parts and will facilitate targeted production of citrus pectin for high-value utilization.

The Use of Pectins As Part of a Cryoprotective Solution For Long-term Storage of Human Platelet Concentrates

BACKGROUND: Pectins have unique properties and great potential to become an indispensable component of cryoprotective environment for platelet freezing. OBJECTIVE: To investigate the possibility of including pectins (apple pectin AU-701, tanacetan) into the composition of a cryoprotective solution for platelets during low-temperature storage. MATERIALS AND METHODS: Samples of platelet concentrates (PC) were frozen under the protection of complex solutions and stored in an electric freezer at -80 °C for 1 and 6 months. RESULT: The study showed that of the basic cryoprotectants, the best effect in the preservation of PC was with dimethylacetamide (DMAC). The use of pectins as an additive to the base solution of DMAC statistically improves the preservation of PC after exposure to low temperatures (-80 ° C) for 30 and 180 days. CONCLUSIONS: We conclude that DMAC is more promising as a basis for the development of a new combined cryoprotectant for PC freezing. Moreover, the chemical structure of pectin determines the level of its cryoprotective action in relation to the preservation of PC.

The Effects of Pectin Structure on Emulsifying, Rheological, and In Vitro Digestion Properties of Emulsion.

Pectin, a complex hydrocolloid, attracts extensive attention and application stemming from its good emulsification. However, the source of emulsification remains a conundrum. In this experiment, the structures of six kinds of commercial pectin, including LM 101 AS (101), LM 104 AS (104), 121 SLOW SET (121), YM 150 H (150), LM 13 CG (13CG), and β-PECTIN (β-P) were determined, and the effects of pectin structure on emulsion emulsification, rheology and in vitro digestibility were studied. The results showed that the β-P pectin contained a higher content of protein, ferulic acid, and acetyl and had a lower interfacial tension; this pectin-stabilized emulsion exhibited a smaller droplet size and superior centrifugal and storage stability. The results showed that β-P pectin had higher contents of protein, ferulic acid, and acetyl and lower interfacial tension than other pectins, and its stabilized emulsion exhibited smaller droplet size and superior centrifugation and storage stability. Furthermore, the emulsion formed by the pectin with high molecular weight and degree of methoxylation (DM) had a higher viscosity, which can inhibit the aggregation of emulsion droplets to some extent. However, the DM of pectin affected the charge and digestion behavior of pectin emulsion to a great extent. The smaller the DM, the more negative charge the emulsion carried, and the higher the release rate of free fatty acids. The results provided a basis for the rational selection and structural design of the pectin emulsifier.

Effect of solution pulsed plasma process on the degradation and physicochemical properties of pectin

Pectin was degraded by solution pulsed plasma (SPP). The impacts of discharge voltage and the distance between the electrodes on pectin degradation and its steady shear flow behavior and characterization were investigated. The results showed that the influence of the discharge voltage was higher than that of the distance between the electrodes. The stronger discharge voltage and the narrower distance between the electrodes presented the lower intrinsic viscosity, the greater shear-thinning capacities, and the stronger viscoelastic behavior. FT-IR and 1H NMR analysis demonstrated that SPP treatment did not damage the main structure of pectin. XRD, SEM and HPSEC-MALL analysis revealed that the crystallinity, Mw and <S2>z1/2 of pectin gradually decreased with the increasing discharge voltage and decreasing the distance between the electrodes. The depolymerized pectin molecules exhibited a hard sphere conformation in the aqueous solution. A higher degradation effect had a greater influence on the conformation of pectin.

Commercial pectin production from dried florida orange peel: Effect of process conditions on pectin structure and function

AbstractTo determine the feasibility of using Florida, USA, oranges for pectin production, we evaluated the effects of time, temperature, and pH on pectin properties extracted from dried Valencia orange peel using a hot acid process. Juice extracted peel was collected weekly, and following pretreatment, the dried peel was pooled and used to extract pectin with time (4, 5, and 6 h), temperature (65 and 75°C), and pH (1.6 and 1.8) as process variables. Pectin properties, including yield, sugar composition, molecular weight, intrinsic viscosity, degree of methylesterification, degree of branching, degree of blockiness, absolute degree of blockiness, and Standard Acid in Glass (SAG), were determined. In addition, we evaluated the response of each variable to the process conditions using response surface methodology. The analysis of variance (anova) models for molecular weight, intrinsic viscosity, and yield were highly significant, with actual values decreasing with increasing temperature. Increasing reaction time also decreased values for molecular weight and intrinsic viscosity.Novelty impact statementThis study indicates that process time and temperature affected pectin quality, functionality, and yield. Increasing temperature had the most detrimental effect on desirability in an optimization analysis.

Preparation of branched RG-I-rich pectin from red dragon fruit peel and the characterization of its probiotic properties

Red dragon fruit peel is a pectin-rich fruit waste that is a potential source of prebiotics and whose different sources and structures will influence its prebiotic function. Thus, we compared the effects of three extraction methods on the structure and prebiotic function of red dragon fruit pectin, the results showed that the citric acid extracted pectin produced a high Rhamnogalacturonan-I (RG-I) region (66.59 mol%) and more side-chains of Rhamnogalacturonan-I ((Ara + Gal)/Rha = 1.25), which can promote bacterial proliferation significantly. The side-chains of Rhamnogalacturonan-I may be an important factor in that pectin can promote the proliferation of B. animalis. Our results provide a theoretical basis for the prebiotic application of red dragon fruit peel.

Pectin extraction from garlic waste under dual acid condition

AbstractA novel approach for the extraction of pectin from garlic waste (peel, stem, and straw) was accomplished under dual acid solution conditions including two organic (citric acid [CA] and acetic acid [AA]), two inorganic (hydrochloric acid [HCl] and sulfuric acid [H2SO4]) and six different mixtures of these acids (CA‐HCl, CA‐H2SO4, CA‐AA, AA‐H2SO4, AA‐HCl, and HCl‐H2SO4) with 1/30 (v/w) solid–liquid ratio at 90°C in 90 min extraction duration. The effects of acid mixture on the yields and physicochemical properties of the extracted pectins from garlic waste were investigated. Applying different acid mixtures during the extraction process allowed to obtain pectin samples with controlled physicochemical properties and higher yields. The maximum pectin yield of 22.4% was observed in the extraction condition carried out HCl‐H2SO4 (1/3 v/v) mixture. Extractions carried out under dual acid mixtures showed higher Gal‐A contents compared with the conditions where organic or inorganic acids were used alone. The extracted pectin samples were generally composed of high methoxyl pectin and their methoxyl contents are observed to be close to that of commercial citrus pectin. FT‐IR spectra results of the extracted samples from garlic waste confirmed the pectin structure compared with the FT‐IR spectrum of commercial citrus pectin. Results indicate that organic–inorganic dual acid mixtures could be used as an efficient extraction media for the controlled physicochemical properties and higher yields of pectin extraction. Considering that about 3.7 million tons of garlic waste is annually produced worldwide, it could be very beneficial to obtain pectin from these wastes as a useful product for the industry.Practical applicationsGarlic waste was converted into a valuable product for the industry and used as an alternative pectin source. Applying organic–inorganic dual acid mixtures during the pectin extraction process from garlic waste allowed to obtain pectin samples with controlled physicochemical properties and higher yields. Extracted pectin samples showed higher Gal‐A contents compared with the conditions where organic or inorganic acids used alone. Obtained pectins were generally composed of high methoxyl pectins and their methoxyl contents are observed to be close to that of the commercial citrus pectin.

The role of current herbal extracts in bone regeneration through dental implants: in vitro/in vivo/clinical studies.

The quality and quantity of bone at the interface of an implant system are determining factors in the implant's stability. Alternative agents have been studied to augment implants and bone defects, including bone-conductive and bone-inducing agents. By modifying implant surface coatings on the nanoscale, one can enhance osseointegration by stimulating bone cell adhesion, bone matrix formation, and mineralization. Because alternative agents stimulate osteoblasts to mineralize and can control pectin structure, plant-derived silicone has been suggested as a potential candidate for surface nanocoatings on orthopedic and dental titanium implants. Inducing the differentiation of cells or accelerating bone regeneration is possible with the plant extract. Coating these extracts on implant devices can improve cell attachment, differentiation, and proliferation. This review article discusses the role of herbal materials in bone regeneration through dental implants.

Enhancive effect of instant controlled pressure drop (DIC) pre-treatment on pectin extractability from peach pomace

This study aimed to investigate if instant controlled pressure drop (DIC) processing can enhance pectin extractability from plant material. Peach pomace was treated by 0-, 1-, or 3-cycle of DIC processing at 90 or 105 °C. Pectin fractions including water soluble pectin and insoluble pectin were isolated from dried peach pomace and characterized by degree of methoxylation, neutral sugar composition, and molecular weight distribution. The results demonstrated that the thermomechanical effect of DIC processing induced a strong solubilization of in situ pectic polysaccharides of peach pomace, especially for water insoluble pectin fractions. This solubilization effect resulted in a more than 10% increasing ratio of extractable pectin yield from peach pomace over the maximum yield without the thermomechanical effect of DIC processing. Meanwhile, DIC processing conducted at 90 °C with 1-cycle affected pectin structure and property insignificantly. • DIC process induced solubilization of in situ pectic polysaccharides of peach pomace. • DIC treatment increased the pectin extractive yield of peach pomace by more than 10%. • 1-cycle DIC treatment at 90 °C affected slightly on pectin structure and properties.

Emulsifying and emulsion stabilization mechanism of pectin from Nicandra physaloides (Linn.) Gaertn seeds: Comparison with apple and citrus pectin

The emulsifying and emulsion stabilization mechanism of three kinds of pectin (Nicandra physaloides (Linn.) Gaertn seeds pectin-NP, apple pectin-AP, and citrus pectin-CP) were compared in terms of emulsions system, interface layer and pectin structure. The results showed the emulsifying properties of NP was superior to AP and CP, which attributed to lower interfacial tension (∼15.57 mN/m) and better long-term stability to prepared emulsion. The long-term stability of NP emulsion ascribed to the higher emulsion viscosity, more uniform droplet size distribution, stronger electrostatic repulsion, and thicker interfacial layer. Structurally, the emulsifying activity of NP was mainly provided by acetyl and methyl groups, and the emulsifying stabilization was provided by the neutral monosaccharide side chains and ionized carboxyl groups. Therefore, the protein in pectin was not essential for the stabilization of oil-water interface, and the carbohydrate components played a crucial role in when especially lack of protein. Consider that the emulsifying properties of NP were independent of protein, it may be a potential natural emulsifier in resisting acid, ions, and heat.

Physicochemical and morphological characteristics of potato pectin with in-situ acid-induced gelation.

Pectin in the potato cell wall plays an important role in strengthening connections of intercellular junctions during thermal processing through in-situ acid-induced gelation (in-situ acid-induced gelation [AIG]). Thus, the variation in the physicochemical and structural characteristics of potato pectin with in-situ AIG was focused in this study. The intra- and intermolecular hydrogen bonding among (d-galacturonic acid) GalA units around 3400cm-1 (absorbance intensity was increased from 50.9 to 70.7) in Fourier transform infrared spectra were enhanced in the pectin with in-situ AIG. The crystallinity of pectin with in-situ AIG increased from 4.02% to 36.63%. Atomic force microscopy revealed that pectin with in-situ AIG was made up of wide linear strands with the length from 0.5 to 4.6µm. Thermogravimetric and rheological analysis showed that the structure of potato pectin was more stable and resistant to heat processing after in-situ AIG. These observations proved that the complex structure of potato pectin with in-situ AIG linked with its thermal stability. PRACTICAL APPLICATION: In-situ gelated pectin in the intercellular space caused a helpful structure modification of vegetable to maintain its hardness with heat process. This study will provide novel insights into the physicochemical properties of in-situ gelated pectin in the potato cell and useful knowledge on the behavior of pectin during the preparation of potato products.

Effects of ultrasonic on structure, chain conformation and morphology of pectin extracted from Premna microphylla Turcz

In this study, ultrasonic effects on structure, chain conformation and morphology of pectin extracted from Premna microphylla Turcz (PEP) and its probable mechanism were investigated. In the process of ultrasonic treatments, the chains of PEP were fractured rapidly within the initial 10 min and then the degradation rate gradually slowed down. The primary structure of PEP nearly remained unchanged after ultrasonic degradation. The rigid semi-flexible chains of PEP were converted into flexible chains, flexible coils, even compact coils. Sonication at low intensity for short time made PEP molecular chains curly collapse and tighten up. Long duration sonication at high intensity generated excessive small rigidness segments that mutually aggregated because of hydrogen bonds and inhibited the self-coiling of PEP chains. Atomic force microscopy (AFM) analysis supported the conformation transition of PEP chains. The results provided a fundamental basis for orientation design and process control of PEP structure.

Propiedades estructurales, fisicoquímicas y emulsionantes de la pectina obtenida por extracción acuosa de la cascara de la pitaya roja (Hylocereus polyrhizus)

This work aimed to carry out a straightforward aqueous extraction of pectin from red pitaya peels (RPP), in a drive to promote the circular economy of the settlements where the fruit of this endemic species grows. The average pectin yield was 11.59 g/100 g dry basis, the degree of esterification was 60.35±1.35%, the galacturonic acid content was 54.36±1.03%, and the protein content of 5.86 ± 0.25%. The RPP pectin was analyzed in terms of physicochemical, functional, and structural features. The FTIR spectrum confirmed that the unveiled pectin structure was consistent with that reported for commercial pectins from different botanical sources. Pectin aqueous dispersions exhibited power-law shear thinning behaviour. Corn oil (10 mL) in 150 mL aqueous pectin solutions (0.12, 0.15, 0.30, 0.60 and 0.90%, w/v) emulsions exhibited increasing emulsifying activity and emulsifying stability with increased pectin concentration. The small It was concluded that the RPP pectin is an alternative potential new source of pectin for use in the formation and stabilization of oil-in-water food emulsions.

Structure of pumpkin pectin and its effect on its technological properties

Abstract The aim of this work is to investigate the structural features, physicochemical, rheological, and emulsifying properties of pectin extracted from pumpkin “Cucurbita maxima” pulp and peel. After the peel and pulp of fresh pumpkin were solubilized in water at high temperature (80°C) and clarification, the obtained filtrate was treated with aluminum sulphate, which precipitates a fibrous coagulum. The results found that the major functional groups of pectin isolates identified by Fourier transform infrared are: –OH, CH2, C═C, –C–O–C–, and CH3. The results obtained using nuclear magnetic resonance methods suggest that these polysaccharides consist of two domains: the first one is homogalacturonan and the second is formed by rhamnogalacturonan. Mineral and metal ions on pectin surface detected using scanning electron microscopy coupled to energy dispersive X-ray analysis were different pulp and peel pectin. Rheological behavior of these biopolymers is suitably represented by the Herschel–Bulkley and power law models. The extracted pectin has a viscosity spectrum expressed by the following properties: G′, G′′, G*, and ∣ η ̇ ∣ ( ω ) | \dot{\eta }| (\omega ) which, respectively, have the following values: 0.28–57.63, 0.15–34.38, 0.39–67.12, and 1.82–831.08 Pa s. These macromolecules have a negative charge on their surface. Rheological properties and emulsifying activity are significantly influenced by the structural composition and physicochemical properties.