Degree Of Pectin Esterification Research Articles

The mitigation of citric acid on cadmium toxicity in Iris tectorum and its effects on the composition of cell walls

Cadmium (Cd), a widely distributed and highly toxic heavy metal, poses a severe threat to soil fertility and plant growth. Citric acid (CA), a small organic acid molecule, plays a crucial role in alleviating heavy metal toxicity in plants. However, the specific mechanism underlying how CA organizes and mitigates the damage caused by heavy metals to plant cells remains unclear. Therefore, we studied the impact of exogenous CA on Cd-induced stress in Iris tectorum. The results showed that the addition of exogenous CA significantly increased the activity of antioxidant enzymes and altered the content of mineral elements including Fe, Zn, Ca, and Mn. Notably, compared to the Cd-only treatment, the proportion of Cd in the root cell walls increased by 14% in the presence of CA, and this increase was due to the ability of CA to regulate the amount of polysaccharide components in the root cell walls. CA affected the activity of pectinesterase (PME), changed the degree of pectinesterification (PMD), and enhanced the root cell walls’ ability to bind Cd, thereby reducing the Cd content in the above-ground tissues and alleviating heavy metal toxicity in plants. In summary, this study provides robust evidence that supports the use of CA to improve the efficiency of urban soil remediation.

Effect of pre-treatment on the change of frozen pineapple texture

Extending pineapple shelf-life and controlling freezing is a trade concern. This study investigated the effect of 5 degrees of ripeness (DR) and 4 pre-treatment methods on the texture of frozen pineapple. Freezing time, freezing rate, degree of pectin esterification (DE), relative hardness (RH) and core temperature change mechanism (TCM) during freezing were evaluated. Kinetic models were developed to describe the RH change. Pineapples (25 % greenish yellow), the shortest freezing time was observed. The TCM was divided into 3 stages. The DE remained stable after freezing but decreased with increasing DR. A blanching method, followed by soaking in CaCl2, and a blanching method using a CaCl2 solution were effective in preserving the texture of frozen pineapple. A fractional conversion model was proposed to describe the mechanism of texture changes in pineapple during freezing. This study serves as a basis for enhancing the texture and promoting the international trade of pineapple.

Effects of Pectin on Intestinal Microbiota and Human Health

Gut microbes are important players in human metabolism and their genomes are abundant in genes that regulate the metabolism of SFCAs, methane, amino acids, and carbohydrates. Pectin is a water-soluble dietary fiber, an abundant heteropolysaccharide in the main and intermediate cellular lamellae of plant cell walls. Pectin is degraded by a varied group of microorganisms residing in the human gut, which depolymerize pectin by secreting both cell-bound and extracellular enzymes to produce monosaccharides. The pectin fermentation degradation pathway is the main mechanism for the degradation of carbohydrates that cannot be digested in human GIT, and the end products include SCFAs, ethanol, CO2 and H2. The makeup of intestinal microbiota is impacted by these products. Additionally, the effect of pectin on intestinal microbial fractions is related to the structure of pectin, the intestinal environment and the degree of pectin esterification. Moreover, pectin itself and pectin degradation products contribute to human health by influencing intestinal microorganisms. Pectin is effective in modifying allergies to sensitization, reducing body composition and has a preventive effect on type I diabetes.

Extraction of Pectin and Cellulose from Grapefruit Peels and Production of Carboxymethyl Cellulose

The peels of grapefruit are a rich source of Pectin and Cellulose. This study focuses on the extraction of Pectin and Cellulose from grapefruit peels, and the production of carboxymethyl Cellulose (CMC) from extracted products. Firstly, the extraction conditions of Pectin from grapefruit peels were optimized to obtain a high yield of Pectins such as extraction time and citric acid concentration. The weight, purity, and esterification degree of Pectin were also determined. The highest yield of Pectin is 32.12% in the extraction conditions with pH 1.25 for 60 minutes at 80 oC. The Pectin product is of 84.02% purity at 29,427 g/mol of weight with 86.40% esterification degree. For extraction of Cellulose from grapefruit peels, the highest yield of Cellulose is 45.08% in the conditions with a pH of nitric acid 0.75 for 70 minutes at 90 oC. After that, the extracted Cellulose was converted to Carboxymethyl Cellulose by Monochloroacetic acid etherification. The characterization of Pectin, Cellulose, and CMC is determined through Scanning Electron Microscopy (SEM) and Infrared spectrums. The experimental results also showed that Pectin and Cellulose were successfully extracted from grapefruit peels and Carboxymethyl Cellulose was successfully produced from the extracted Cellulose.

Fine physicochemical, structural, rheological and gelling properties of tomato pectin under infrared peeling technique

To protect the pulp quality, the effect of infrared peeling on the physicochemical, structural, rheological, and gelling properties of tomato pectin was investigated using newly developed catalytic infrared peeling equipment and compared with manual, hot-water and lye peeling. Compared to manually peeled pectin, the results showed that hot-water peeling reduced the pectin yield by 13.19% but significantly increased the pectin's Z-average radius of gyration (Rg) and hydrodynamic radius (RH). And the pectin gel had excessive hardness. Lye peeling reduced the pectin yield by 30.43%, the degree of esterification (DE) by 25.97%, RH by 7.8 nm and Rg by 2.9 nm. And the pectin gel had the worst water-holding capacity and texture. The yield and DE of pectin (IPP) after infrared peeling only decreased by 3.88% and 0.9%. IPP exhibited moderate physicochemical, structural, rheological, and gelling properties, which was the closest to manually peeled pectin. IPP gel showed steady viscoelasticity and high water-holding capacity (96.71%). Conclusively, the infrared peeling technique can provide better pulp quality and is sustainable.

Effect of acid type and concentration on the yield, purity, and esterification degree of pectin extracted from durian rinds

This current research aimed to investigate the effect of acid type and concentration on the yield, anhydrouronic acid content (AUA), and esterification degree (DE) of durian rind pectin by using three types of mineral acids (hydrochloric, sulphuric, and nitric acids) and three types of organic acids (citric, tartaric, and acetic acids) at five different concentration (0.0001, 0.001, 0.01, 0.1, and 1.0 M). The pectin yield (0.93–10.23%), AUA (41.64–80.58%), and DE (0.43–25.69%) were pronouncedly affected by the acid type and concentration during extraction. The results were affected by the strong-weak and protic nature of the acids. The pectin yield and DE decreased at higher acid concentrations (0.1, 1.0 M), with mineral acids giving a more significant effect. Additionally, mineral acids were more effective in extracting pectin with greater purity (AUA > 65%). In contrast, organic acids-extracted pectins had AUA < 65%, indicating poor purity. All pectins extracted were low-methoxyl pectin (LMP) with DE < 50%. Based on the results, mineral acids appeared to be more suitable for durian rind pectin extraction than organic acids due to their good yield and purity of LMP. The FTIR spectra showed that durian rind pectins were rich in homogalacturonan content. 0.001 M H2SO4 could be a promising extractant for commercial LMP production (DE = 20.11%) from durian rind, considering its satisfying yield (9.13%) and purity (AUA = 66.72%), in which the LMP could be a potential thickener and stabilizer for low-calorie foods and beverages.

Characterize the physicochemical properties and microstructure of pectin from high-pressure and thermal processed cloudy hawthorn (Crataegus pinnatifida) juice based on acid heating extraction

Physicochemical properties and morphological features of pectin in high-pressure-processing (JHPP) and thermal-processing (JTP) treated cloudy hawthorn juice were investigated based on acid heating extraction. Pectin from hawthorn juice was identified as low methoxy pectin (41.77%), which was significantly reduced to 34.56%-39.51% from JHPP, while pectin esterification degree (DE) from JTP increased to 45.58%, which can also be confirmed by Fourier transform infrared spectroscopy. In comparison to control, pectin linearity of JHPP and JTP significantly decreased with more highly branched-chains. However, no significate difference was observed in thermostability, crystallinity and main functional groups. Interestingly, a large number of aggregations was observed in JHPP pectin, and the intermodular distance of JTP pectin was enhanced, which was consistent with the results of viscosity, molecular weight and DE. These findings provided insights into utilization of hawthorn pectin and application of high-pressure processing (HPP) for improving quality property of fruit products by pectin modification.

Research Progress of Pectin Methylesterase and its Inhibitors.

As an important pectin enzyme, pectin methylesterase (PME) can hydrolyze methyl esters, release methanol and reduce esterification. It is essential in regulating pollen tube development, root extension, and fruit ripening. Pectin methylesterase inhibitors (PMEI) can specifically bind PME and inhibit its activity, which jointly determines the esterification degree of pectin. PMEI has important application prospects in plant pest control, fruits and vegetable processing fields. In this paper, the gene families, crystal structures, molecular recognition, and applications in plants and industry are reviewed for the PME and PMEI systems. Finally, the semi-rational design of PMEI is discussed and discussed prospected.

Pengaruh Waktu Ekstraksi pada Pektin Ampas dan Kulit Buah Melon (Cucumis Melo L. var. Sky Rocket)

The purpose of this study was to determine the effect of extraction time on yield, methoxyl content and degree of esterification. In this study, the raw materials used are melon pulp and peel. The process of obtaining pectin from raw materials is reflux extraction with the extraction time of 60, 90, and 120 minutes using citric acid pH 2.5 as a solvent. The result shows pectin yield for each extraction time of 60, 90, and 120 minutes to be 4.16%, 11.91%, and 5.49% for melon pulp and 2.29%, 6.86%, and 3.57% for melon peel, respectively. Methoxyl content of pectin increases with increasing extraction time to be 2.05%, 3.41%, and 3.78% for melon pulp and 2.17%, 2.73%, and 3.72% for melon peel, respectively. Pectin esterification degree decreases with increasing extraction time to be 48.53%, 44%, and 33.52% for melon pulp and 46.67%, 39.29%, and 30.93% for melon peel, respectively. Methoxyl content value of &lt;7% and esterification degree of &lt;50% shows pectin obtained from this study is the low-methoxyl pectin.

Effect of Structurally Different Pectin on Dough Rheology, Structure, Pasting and Water Distribution Properties of Partially Meat-Based Sugar Snap Cookies.

Pectin has been widely used as a hydrocolloid in foods, but its effectiveness based on hydrodynamics radius (Rh), average side chain length (ACL) and degree of esterification (DE) has been less studied. This study investigated the effect of 4 types of pectin (with different molecular weight and structures) at a level of 1.5% w/w of wheat flour on functional, structural and water binding properties of sugar snap cookies partially substituted with fish meat. The results showed that pectin (CU-201 and CU-601) with higher ACL and Rh controlled excessive expansion, while the improved rheology of dough in terms of behavior as viscous matrix compared to control and other pectin. Texture was found to be highly dependent on Rh and ACL compared to DE of pectin. The pasting properties, especially peak viscosity and final viscosity, were significantly (p < 0.05) increased with increasing DE, as well as ACL, by entangling and increasing the interaction between starch and pectin. The scanning electron microscopy (SEM) analysis exhibited that control sample showed wide voids and more intercellular spaces, while samples prepared with CU-601, CU-201, and CUL displayed compact structure, which was also evidenced by controlled expansion and improved hardness of the cookies. Low field nuclear magnetic resonance (LF-NMR) analysis showed that T21 relaxation time and amplitude were found to be shorter for CU-601 and CU-201 treatments, signifying the high amount of tightly bound water compared to control. The findings endorse the feasibility of adding CU-601, and CU-201 as an efficient hydrocolloid for the improved structural and functional properties of cookies.

Optimization the conditions of process of production of pectin extracted from the waste of potato peel

The objective of this study is to investigate the effect of three variables including temperature (35, 65 and 95°C), time (40, 120 and 200) and pH (1, 2 and 3) on the yield, galacturonic acid percentage and degree of pectin esterification extracted from the potato peels and optimization of the condition of extraction. Response surface method is used to optimize the conditions of extraction. Physicochemical properties of extracted pectin under optimum conditions were compared with commercial citrus and apple pectins by pectin flow behavior tests at different concentrations, FT-IR spectrum and pectin molecular weight. The results showed that the highest extraction yield was 14.87% at 95°C, 120 min time and pH 1. The highest percentage of extracted galacturonic acid pectin in potato peel was 36.37% at 95°C in 120 min and pH 1. The highest degree of esterification of extracted pectin from potato peel was 41.820% at 65°C in 40 min time and pH 3.00. Simultaneous optimization of extracting pectin with the aim of achieving maximum yield was galacturonic acid with 100% desirability at 95°C, 200 min time and pH 1 that in this condition, the yield was 15.23% and galacturonic acid was 38.0712%. The highest stability of extracted pectin emulsion from potato peel was observed at 4°C on the first day. Also, the FT-IR results showed that the strong absorption between 3200-3500 cm-1 in the extracted pectin sample was related to the intracellular and extracellular vibration of the hydrogen bond in the galacturonic acid polymer. The molecular weight of extracted pectin from potato peel under optimum conditions was 53.46 kDa after 30 days of storage at 4 and 23°C with emulsion stability 85.1 and 63.1, respectively. The results of this research showed that extracted pectin from potato peel can be introduced as a source of pectin to the market.

Characterization of apple cultivar susceptibility to Neofusicoccum parvum Brazilian strains

Due to climate change, Neofusicoccum parvum is currently emerging as a new pathogen of Rosaceae plant species. This increases the need of gaining knowledge on the pathogenicity of this fungus, particularly on apple cultivars of considerable economic importance. In this study, the virulence and temperature dependence of N. parvum isolates was assayed on ‘Gala’ and ‘Fuji’ apple fruit and wood. At 25 °C and 30 °C, ‘Gala’ fruits showed a higher susceptibility to all fungal strains than ‘Fuji’, whereas low infection severity was shown at 15 °C and 20 °C on both cultivars. Infrared spectroscopy revealed that ‘Fuji’ fruit tissues displayed a higher content of phenolic compounds and pectin esterification degree, as factors possibly correlated with fruit susceptibility. When strain virulence was assayed on wood, no significant difference in susceptibility was detected, as also shown by SEM analysis. The virulence of N. parvum was also tested by assaying the activity of lytic enzymes such as cellulase, polygalacturonase, polymethylgalacturonase, and xylanase.

Effect of high hydrostatic pressure processing on textural properties and microstructural characterization of fresh‐cut pumpkin (Cucurbita pepo)

AbstractHigh hydrostatic pressure (HHP) processing is a burgeoning nonthermal sterilization technology has been industrialized in foreign countries. The purpose of this research was to investigate HHP (100–600 MPa/2 min)‐induced texture and cell microstructural changes of fresh‐cut pumpkins compared with untreated and heated samples. Treatment efficacy was evaluated by texture profile analysis and combinational microscopy techniques, including transmission electron microscope (TEM) and confocal imaging. The results showed that the texture of pumpkin was jointly influenced by HHP‐triggered alterations in pectin characteristics, membrane completeness, and morphology of tissue. Samples subjected to HHP treatment could better maintain original histology properties than heated ones based on color parameter, hardness, relative electrical conductance, and degree of pectin esterification, among which moderate pressure (300–400 MPa) exerted more positive effects. Our findings provide theoretical guidance for the correlative application of HHP and promote further investigation on food varieties.Practical ApplicationsHHP processing is a commercially implemented technology being used in vegetable‐based products. As an important factor highly correlated with freshness, texture alterations induced by processing are an industrial issue of great concern. This work provides new evidence on the softening mechanism comprehensively with respect to pectin, membrane, and morphology of tissue. The application of our current findings could be applied in other temperature‐sensitive food substrates and make it possible to produce products of high quality in mild temperature.

Comparative Studies of Combined Influence of Variables on the Esterification Degree of Pectin Extracted by Sulfuric Acid and Citric Acid

The influence of extraction variables on degree of esterification (DE) of pectin was studied due to the significant effects of DE on the properties of the pectin-based functional biomaterials. The extracting agents (sulfuric acid and citric acid), pH value of extraction solution, extraction time, and temperature were selected to study the hydrolysis reaction of carboxylic acid ester by response surface methodology (RSM). The hydrolysis reaction occurred more violently in the weak organic acid solution than that in the strong inorganic acid solution. The DE was significantly influenced by pH of extraction solution, extraction time, and temperature through the analysis of variance. In addition, the values of DE reduced with the increasing of extraction temperature, lapse of time, and decreasing of pH value. What is more, the effects of extraction conditions on the yield, monosaccharide composition, content of protein, and ferulic acid were also studied. It is evident that the lower pH value contributed to higher extraction yield. The content of Total CH and GalA of pectin extracted by sulfuric acid were higher than that of pectin extracted by citric acid, and the content of monosaccharide showed an opposite trend.

Increased firmness and modified cell wall composition by ethylene were reversed by the ethylene inhibitor 1-methylcyclopropene (1-MCP) in the non-climacteric olives harvested at dark green stage – Possible implementation of ethylene for olive quality

This study aimed to investigate the firmness retention by ethylene treatment in olive fruit, as observed earlier. Ethylene concentrations up to 1000 μL L−1 were applied to dark green ‘Konservolia’ olives harvested shortly before the green maturation and exposed to 20 °C for up to 9 d. Surprisingly, the results indicated a tendency to fruit firmness increases in concentration-dependent manner in a non-climacteric fruit. The highest concentration increased the firmness within 12 h by approximately 1.35-fold, but transiently for approximately up to 5 d; all ethylene inhibitors tested, either of synthesis (ethoxyvinyl glycine or AVG), or perception (1 -methyl-cyclopropene or 1-MCP, and silver nitrate) prevented the firmness increase. Texture was evaluated by firmness and changes in lignin, cellulose (CL), total pectins (TPC), water soluble pectins (WSP) and total non-cellulosic sugars (total sugars) concentrations, and in pectin esterification degree (DE) in the alcohol insoluble residue (AIR) of ‘Konservolia’ fruit pericarp during 1.5-d, 5-d and 10-d treatments with 1000 μL L-1 ethylene at 20 °C. Pectins in AIR were also extracted sequentially with cyclohexane-trans-1,2-diaminetetra-acetate (CDTA), Na2CO3, 1 M and 4 M KOH. The results showed that on day 1.5, the increased firmness was consistent with increased CL (crystalline formation, as observed by microscopy), total sugars and DE levels, but reduced WSP, whereas softening reversed the changes and lowered TPC and CDTA-soluble pectins in all fruit on day 10. However, on day 5 ethylene-treated olives exhibited a transitional phase during softening, characterized by retention of high TPC concentration and energy demand, as indicated by elevated respiration rates. The inhibitor 1-MCP, applied before ethylene, did inhibit the responses to ethylene treatment. Ethylene firming effect and the respective cell wall changes in olives are demonstrated for first time. The experiments could be used for research on perception and transcription responses to ethylene in olive, a non-climacteric fruit. In practice, high ethylene concentrations could also be beneficial for firmness increase and/or short storage of dark green olives.

Gelatin and pectin complex coacervates as carriers for cinnamaldehyde: Effect of pectin esterification degree on coacervate formation, and enhanced thermal stability

This study developed the multinuclear microcapsules by the complex coacervation between gelatin (G) and high methyl pectin (HMP), low methyl pectin (LMP) as a delivery system for cinnamaldehyde. The parameters affecting the formation of such carriers were investigated by dynamic light scattering and microscopic techniques. Fluorescence analysis and Fourier-transform infrared (FTIR) were used to study protein conformation change during coacervate formation between gelatin and pectin. The results showed that high yield of coacervates with good size and morphology occurred at pH 4.23 and 4.37 for G/HMP with a ratio of 3:1 and G/LMP with a ratio of 6:1 respectively. Fluorescence and FTIR analysis further confirmed their electrostatic interaction and gelatin molecules exhibited a conformational change following the complexation. Thermal gravimetric analysis revealed that microencapsulation of cinnamaldehyde by complex coacervation using gelatin and pectin significantly increased the degradation temperature from 180-220 °C to 350–400 °C. Moreover, high methyl pectin revealed a higher encapsulation efficiency (89.2%) and controlled release of cinnamaldehyde in hot water (33% for 120 min at 80 °C). It could be suggested conformation of pectin types and gelatin might significantly contribute to the overall complexation and cinnamaldehyde microcapsule properties. These findings could be useful for design an ideal carrier to deliver flavors like cinnamaldehyde by complex coacervation using protein and different pectin types.

Optimization of pectin extraction from pistachio green hull as a new source

In this paper, the influence of pH (0.5–2.5), temperature (50–90°C), extraction time (30–150min) and liquid/solid ratio (10–50v/w) on the acidic extraction yield and degree of esterification (DE) of pistachio green hull pectin were studied by using central composite design. The results indicated that the yield and DE of pectin ranged from 7.31 to 19.02% and 26.00 to 53.01%, respectively. The optimization of pectin extraction condition showed that the optimal condition was pH of 0.5, temperature of 90°C, time of 30min and liquid/solid ratio of 50 v/w. In this condition, the experimental yield (22.1±0.5%) was fine accord among predicted yield (23.42%). Also, under the optimal extraction condition, the galacturonic acid content of pectin was about 65%. The FTIR spectrum showed that the pectin extracted under optimal condition is rich from polygalacturonic acid.

Pectin Esterification Degree in the Bioavailability of Non-heme Iron in Women.

Pectins are a type of soluble fiber present in natural and processed foods. Evidence regarding the effect of esterification degree of pectins on iron absorption in humans is scarce. In the present study, the effect of pectins with different degrees of esterification on non-heme iron absorption in women was evaluated. A controlled experimental study was conducted with block design, involving 13 apparently healthy, adult women. Each subject received 5mg Fe (FeSO4) without pectin (control) or accompanied by 5g citrus pectin, two with a low degree of esterification (27 and 36%), and one with a high degree of esterification (67 to 73%), each on different days. Each day, the 5mg Fe doses were marked with radioactive 59Fe or 55Fe. Radioactivity incorporated into erythrocytes was determined in blood samples 14days after the marked Fe doses were consumed. On days 18 and 36 of study, 30 and 20mL blood samples were obtained, respectively, and blood sample radioactivity incorporated into erythrocytes was determined. Body iron status was determined from blood taken on day 18. Whole body blood volume was estimated for calculate iron bioavailability; it was assumed that 80% of absorbed radioactivity was incorporated into the Hb. All women participants signed an informed consent of participation at baseline. Iron bioavailability (mean geometric ±1 SD) alone (control) was 18.2% (12.3-27.1%), iron + pectin27 was 17.2% (10.2-29.2%), iron + pectin36 was 15.3% (9.5-24.6%), and iron + pectin67 was 19.5% (10.0-38.0%). No statistically significant differences between iron bioavailability (repeated measures ANOVA, p=0.22) were observed. Pectin esterification degree does not influence the bioavailability of non-heme iron in women.

Effect of high pressure homogenization and high power ultrasound on some physical properties of tomato juices with different concentration levels

The effect of high pressure homogenization (HPH) and ultrasound (US) on rheological properties, color, precipitate weight ratio, pectin esterification degree and cell integrity of tomato juices with different soluble solids content (5.0, 7.5, 10.0 °Brix) was studied. Samples were subjected to HPH up to 150 MPa or US up to 30 min. The energy efficiency associated to the processes was also evaluated. Results showed that stress type and product concentration influenced the changes of tomato juice physical properties. In particular, HPH and US treatments were responsible for higher G′ and consistency of processed tomato juices than untreated samples. Increases in sample rheological properties were comparable for the 5.0 and 7.5 °Brix treated HPH and US samples, whereas HPH was more effective than US in the case of 10.0 °Brix sample. These changes were in agreement with other indexes, i.e. precipitate weight ratio increase and cell integrity decrease, and were attributed to stronger of inter-particle interactions. The process energy efficiency showed that lower energy was involved in HPH in comparison to US.

Nisin-loaded pectin and nisin-loaded pectin-inulin particles: Comparison of their proteolytic stability with free nisin

Proteolytic stability of nisin-loaded pectin and nisin-loaded pectin-inulin particles, previously developed for food preservation, was investigated and compared with free nisin. The acid protease from Aspergillus saitoi and trypsin were used. The hydrolysis of free nisin by the mentioned proteases resulted in four and three peaks of degradation products, respectively, in the analysis by capillary zone electrophoresis method. The complexation of nisin with biopolymers increased its proteolytic stability. The areas of detected peaks significantly decreased. The stability of particles was dependent on the degree of pectin esterification. The particles prepared using pectic acid or the pectin with low degree of esterification exhibited the highest proteolytic stability. Overall, nisin-loaded pectin-inulin particles were more stable than nisin-loaded pectin particles.