Extraction and partial characterization of Solanum lycocarpum pectin

Differences in physicochemical properties of pectin extracted from pomelo peel with different extraction techniques

In order to obtain high yield pomelo peel pectin with better physicochemical properties, four pectin extraction methods, including hot acid extraction (HAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction, and enzymatic assisted extraction (EAE) were compared. MAE led to the highest pectin yield (20.43%), and the lowest pectin recovery was found for EAE (11.94%). The physicochemical properties of pomelo peel pectin obtained by different methods were also significantly different. Pectin samples obtained by MAE had the highest methoxyl content (8.35%), galacturonic acid content (71.36%), and showed a higher apparent viscosity, thermal and emulsion stability. The pectin extracted by EAE showed the highest total phenolic content (12.86%) and lowest particle size (843.69 nm), showing higher DPPH and ABTS scavenging activities than other extract methods. The pectin extracted by HAE had the highest particle size (966.12 nm) and degree of esterification (55.67%). However, Fourier-transform infrared spectroscopy showed that no significant difference occurred among the different methods in the chemical structure of the extracted pectin. This study provides a theoretical basis for the industrial production of pomelo peel pectin.

Comprehensive evaluation of the chemical profile and antioxidant potential of buritirana (Mauritiella armata) an underexplored fruit from Brazilian Cerrado

Buritirana (Mauritella armata) is a fruit from a native Brazilian palm tree whose economic and industrial potential is still little explored. The nutritional composition and carbohydrates; organic acids; fatty acids; triacylglycerol; and phenolics profile of buritirana pulp, shells, and seeds were performed in this study. In addition, pH, color, ant total carotenoid, phenolic, flavonoids, flavonols, tannins, and antioxidant potential (ABTS, DPPH, ILP, FRAP, CUPRAC, and TRC) were determined in these parts of the fruit. The results indicated high lipid content and energy value for pulp (30.53 g 100 g-1, and 351.21 kcal 100 g-1, respectively) and shells (18.41 g 100 g-1, and 276.73 kcal 100 g-1, respectively). On the other hand, high fiber (63.09 g 100 g-1), starch (2.66 g 100 g-1), and carbohydrates (28.60 g 100 g-1) contents were observed for the seeds. Glucose was the main carbohydrate found in pulp and seed, while sucrose was the main sugar in shells. Tartaric acid was the predominant organic acid in pulp and shells (16.60 and 10.96 mg 100 g-1, respectively), while malic acid was the main organic acid in seeds (58.78 mg 100 g-1). Oleic and palmitic acid were the main fatty acids detected in buritirana pulp, shells, and seeds. Buritirana pulp and shells showed a high content of total phenolic and total flavonoid (918.58 and 940.63 mg GAE 100 g-1; and 679.31 and 444.94 mg CE 100 g-1, respectively). Moreover, a high antioxidant potential (DPPH•, CUPRAC, and ILP) was observed in the extracts obtained from pulp and shells. The pulp showed a significant content of carotenoids (270.23 μg g-1). Among the 28 phenolic compounds determined in buritirana pulp and seeds, and 27 in shells, 22 (pulp and seeds), and 21 (shells) were reported by first time in the literature. Ferulic acid in pulp and shells (99.39 and 111.69 μg g-1) and pinocembrin in seeds (19.21 μg g-1) were the main phenolic compounds identified in buritirana. Multivariate analysis showed high correlation of phenolic compounds on antioxidant potential. The results showed that buritirana is rich in nutrients and bioactive products and can be fully utilized. The products resulting from buritirana processing can be applied in the food, cosmetics, and pharmaceutical industries.

Pectin-like polysaccharide extracted from leaves Crataeva tapia promotes antioxidant, immunomodulatory and emulsifiers applied in therapeutic formulations

The objective of this work was to isolate a polysaccharide similar to pectin from Crataeva tapia leaves, not yet reported in the literature, and to evaluate its antioxidant, cytotoxic and immunomodulatory profile. Pectin was extracted from the leaves in three stages, organic solvent followed by acidified water and ethanol precipitation. With the pectin obtained, the physicochemical characterization of the molecule was carried out using high-performance liquid chromatography, Fourier-transform infrared spectroscopy, nuclear magnetic resonance (13C and 1H) and different thermal and elemental analysis. Furthermore, the antioxidant activities were evaluated in vitro, and using human peripheral blood mononuclear cell culture, cytotoxicity and immunostimulatory actions were investigated. Physical and chemical analyses showed characteristic signs of pectin. Antioxidant activity tests showed that pectin had moderate to low antioxidant activity. Furthermore, pectin did not affect the viability of erythrocytes and PBMC and induced an immunostimulatory state when it promoted the production of cytokines IL-6, IL-10 and TNF-α and increased the activation of CD8 + T lymphocytes. This study showed that pectin from Crataeva tapia is not cytotoxic and promoted a pro-inflammatory profile in peripheral blood mononuclear cell with application as an immunostimulating and emulsifying compound.

Effect of By-Products from Selected Fruits and Vegetables on Gluten-Free Dough Rheology and Bread Properties

The aim of the study was to investigate the effect of using various by-products (orange and apple pomace, tomato peel, pepper peel, prickly pear peel, and prickly pear seed peel) on the dough rheology and properties of gluten-free bread. The by-products were incorporated into a gluten-free bread formulation based on corn and chickpea flours (2/1 w/w). Different levels of each by-product (0, 2.5, 5, and 7.5% in the basic replacement) were tested. Wheat bread and gluten-free bread without the addition of by-products were used as controls. The results indicated that the by-products increased the maximum dough height, the total CO2 production, and CO2 retention coefficient compared to unenriched gluten-free dough. The highest K-value consistency coefficient was observed for the dough enriched with the prickly pear peel. The addition of by-products significantly improved (p < 0.0001) the specific volume of gluten-free bread, with values increasing from 1.48 to 2.50 cm3/g. The hierarchical cluster analysis and the constellation plot showed four groups: the wheat bread group, the second group containing the gluten-free control bread, the group with bread enriched by pomace, and the group with bread enriched with peels, exhibit the same effect on gluten-free bread and the peels exhibit the same effect on gluten-free bread.

A galactose-rich heteropolysaccharide extracted from "jaboticaba" (Plinia cauliflora) peels

The objective of this work was to extract, identify and characterize a galactose-rich heteropolysaccharide (GH) from "jaboticaba" peel. The best conditions to extract the GH according to a 2³ full-factorial experimental design were 90 °C/30 min/pH 1.0, resulting in a 32.32 % yield using lyophilized sample. The chemical structure analyzed by GC/MS and NMR spectra (HSQC/HSQC-TOCSY) showed that the main chain of GH consists of a (1→4) galactoside branched at carbon 3, containing galactose (67.21 %), glucose (15.78 %), arabinose (9.78 %), rhamnose (2.26 %) and traces of esterified and non-esterified uronic acids. Rheological studies revealed that GH suspensions behave as a Newtonian fluid, with calculated molecular mass of 1.48 × 10⁵ Da. The absolute viscosity of 1 % (w/v) aqueous suspension of GH decreased from 25 mPa s to 10 mPa s in NaCl and 7 mPa s in CaCl₂, indicating the polyelectrolyte character of GH.

Optimization of ultrasound-microwave assisted acid extraction of pectin from potato pulp by response surface methodology and its characterization

The ultrasound-microwave assisted HCl extraction of pectin from potato pulp was optimized using the response surface methodology. Effects of extraction temperature, pH, and time on the yield were evaluated, and structural characteristics of pectin extracted under optimal conditions were determined. The yield was 22.86 ± 1.29% under optimal conditions of temperature 93 °C, pH 2.0, and time 50 min. The obtained pectin was rich in branched rhamnogalacturonan I (61.54 mol%). Furthermore, the pectin was a low-methoxyl (degree of methylation, 32.58%) but highly acetylated (degree of acetylation, 17.84%) pectin and the molecular weight was 1.537 × 10⁵ g/mol. Fourier transform infrared spectroscopy and ¹H nuclear magnetic resonance indicated that pectin had a linear region of α-1, 4-linked galacturonic acids which could be methyl and acetyl-esterified, and rhamnose linked with galacturonic acid to form rhamnogalacturonan which was branched with side chains. Scanning electron microscopy showed most of pectin had a lamellae structure.

Physicochemical and functional properties of Cucurbita maxima pumpkin pectin and commercial citrus and apple pectins: A comparative evaluation

The physicochemical characteristics and functional properties of pumpkin (Cucurbita maxima D. var. Cabello de Ángel) pectin obtained by cavitation facilitated extraction from pumpkin pulp have been evaluated and compared with commercial citrus and apple pectins. C. maxima pectin had an Mw value of 90 kDa and a high degree (72%) of esterification. The cytoprotective and antioxidant effects of citrus, apple and pumpkin pectin samples with different concentrations were studied in vitro in cell lines HT-29 (human colon adenocarcinoma) and MDCK1 (canine kidney epithelium). All pectin samples exhibited cytoprotective effect in HT-29 and MDCK1 cells after incubation with toxic concentrations of cadmium and mercury for 4 h. Pumpkin pectin increased the proliferation of cadmium-treated MDCK1 cells by 210%. The studied pectins also inhibited oxidative stress induced by 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) in cell cultures, as determined by measuring the production of intracellular reactive species using dihydrochlorofluorescein diacetate (DCFH-DA). Pectin from pumpkin pomace had the highest (p < 0.05) protective effect against reactive oxygen species generation in MDCK1 cells induced by AAPH. Distinctive features of pumpkin pectin were highly branched RG-I regions, the presence of RG-II regions and the highest galacturonic acid content among the studied samples of pectins. This correlates with a considerable protective effect of C. maxima pectin against oxidative stress and cytotoxicity induced by heavy metal ions. Thus, C. maxima pectin can be considered as a source of new functional foods of agricultural origin.

Pea soluble polysaccharides obtained from two enzyme-assisted extraction methods and their application as acidified milk drinks stabilizers

The objective of this work was characterize and evaluate the protein-stabilizing property of pea soluble polysaccharide (PSPS) extracted from pea by-products using spray-drying and ethanol precipitation oven drying, obtaining PSPS-A and PSPS-B, respectively. The weight average molecular weight (Mw) of PSPS-A and PSPS-B were 625 kDa and 809 kDa, respectively. The results of Fourier transform infrared spectroscopy (FT-IR) analysis indicated that PSPS-A, PSPS-B and soybean soluble polysaccharide (SSPS) contained the same functional groups. The absolute negative charges of PSPS-A or PSPS-B in aqueous solution were slightly higher than that of SSPS at pH 2.0 to 7.0. The apparent diameter of PSPS-B (479.1 nm) was larger than that of PSPS-A (127.7 nm) and SSPS (209.5 nm) were measured by dynamic light scattering. The AFM images revealed that both PSPS-A and PSPS-B possessed star-like structures with more side chains as compared to SSPS. It was found that the addition of 0.15% PSPS-A or 0.1% PSPS-B was adequate to prevent the aggregation of protein and obtain stable dispersion. Furthermore, PSPS has a wider pH range (pH 3.6-4.6) to stabilize milk protein than SSPS (pH 3.6-4.2).

Physicochemical and in vitro antioxidant properties of pectin extracted from hot pepper (Capsicum annuum L. var. acuminatum (Fingerh.)) residues with hydrochloric and sulfuric acids

BACKGROUND

Transformation of hot pepper residues to value-added products with concomitant benefits on environmental pollution would be of great value to capsicum oleoresin manufacturers. Pectin, a soluble dietary fiber with multiple functions, from hot pepper residues was investigated in this study.

RESULTS

The extraction of hot pepper pectin using hydrochloric acid was first optimized using response surface methodology (RSM). The most efficient parameters for maximum hot pepper pectin yield (14.63%, dry basis) were a pH of 1.0, a temperature of 90 °C, an extraction time of 2 h and a liquid-to-solid ratio of 20 L g^-1 . The pectin was mainly composed of uronic acids, and the major neutral sugars were galactose and glucose. The structure of hot pepper pectin was characterized by homogalacturonan and rhamnogalacturonan I elements. The physicochemical properties of hot pepper pectin extracted by sulfuric acid and hydrochloric acid were further investigated. The content of protein and degree of esterification in hot pepper pectin extracted with sulfuric acid solution (SP) were higher (P < 0.05) than those in that extracted with hydrochloric acid solution (HP), while the mean molecular weight of SP was lower than that of HP. Compared with HP, SP exhibited higher viscosity and better emulsifying property.

CONCLUSION

Based on the yield and physicochemical properties of hot pepper pectin, hot pepper residues would be a new source to obtain pectin, and SP would be more preferred than HP. © 2017 Society of Chemical Industry.

Optimized extraction and characterization of pectin from jackfruit (Artocarpus integer) wastes using response surface methodology

The present study was initiated to experimentally optimize the conditions for extraction using Central Composite Design. The optimum temperature and time for the extraction of pectin from Jackfruit wastes using oxalic acid were found to be 90°C and 60min respectively. The yield of pectin under these optimum conditions was 38.42%. Extraction time and temperature showed a significant (p<0.05) effect on the pectin yield. This agreed well with the experimental result of 39.05±0.59g/g of pectin, under similar conditions. Experimental studies on a large scale using 10kg of jackfruit wastes, gave a yield of 38% pectin. Pectin isolated from Jackfruit wastes can be classified as low methoxyl pectin with promising applications in low sugar products.

Structural Characterization and Biological Activities of Polysaccharides from Olive Mill Wastewater

Olive mill wastewater (OMWW), the main waste product of olive oil extraction process, was investigated as a source of polysaccharides. The yield of alcohol insoluble residue (AIR) was 20.5 % based on the dry matter of OMWW. Extraction with water gave water soluble (WSF) and insoluble (WIF) fractions from AIR with yields of 13.3 % (w/w) and 3.7 % (w/w) based on the dry matter, respectively. Chemical composition and monosaccharide analysis indicated that glucose was the main monosaccharide of these extracts in addition to galactose, arabinose, rhamnose, and galacturonic acid. Prebiotic and antioxidant activities of polysaccharidic fractions from OMWW were evaluated. Results gave evidence for their scavenging capacity toward the 2,2'-diphenyl-1-picrylhydrazyle (DPPH) (IC50 value of 89.43 μg/mL) and hydroxyl radicals (IC50 value of 158.70 μg/mL), resistance toward artificial human gastric juice, and ability to be fermented by Lactobacilli strains.

Improvement of starch digestion using α-amylase entrapped in pectin-polyvinyl alcohol blend

Polyvinyl alcohol (PVA) and pectin blends were used to entrap α-amylase (Termamyl) using glutaraldehyde as a cross-linker. The effect of glutaraldehyde concentration (0.25, 0.5, 0.75, 1.0, and 1.25%) on the activity of the immobilized enzyme and rate of enzyme released was tested during a 24 h period. Characteristics of the material, such as scanning electron microscopy (SEM), tensile strength (TS), elongation, and rate of dissolution in water (pH 5.7), ruminal buffering solution (pH 7.0), and reactor containing 0.1 mol L⁻¹ sodium phosphate buffer (pH 6.5), were also analyzed. SEM results showed that the surfaces of the pectin/PVA/amylase films were highly irregular and rough. TS values increased as a function of glutaraldehyde concentration, whereas percentage of elongation (%E) decreased. Pectin/PVA/amylase films presented similar values of solubility in the tested solvents. The material obtained with 0.25% glutaraldehyde performed best with repeated use (active for 24 h), in a phosphate buffer reactor. By contrast, the material obtained with 1.25% glutaraldehyde presented higher performance during in vitro testing using an artificial rumen. The results suggest that pectin/PVA/amylase is a highly promising material for biotechnological applications.

Morphometric and phytochemical characterization of chaura fruits (Gaultheria pumila): a native Chilean berry with commercial potential

BACKGROUND

For the first time, a morphometric characterization of chaura (Gaultheria pumila) fruits has been conducted between natural populations growing in the Villarrica National Park, Araucania Region, Chile. Chaura is a native Ericaceae from Chile that produces aromatic and tasty fruits which could be of agricultural interest.

RESULTS

To influence the decision for a further domestication of G. pumila, both the fruit sizes (indicator of productivity) and the nutritional properties of the fruits have been determined from different subpopulations. Samples were a total of 74 plants and 15 fruits per plant which were randomly harvested following its natural distribution around the Villarrica volcano. Altogether, fresh weight, shape, color, diameter in the pole and the equatorial dimensions were determined as phenotypic traits of the G. pumila fruits. Meanwhile the total soluble solids, anthocyanin and pectin contents were calculated as nutritional traits of the Chaura fruits. Results showed a high phenotypic diversity between the sampled population with three main fruit shapes and three predominant colors. The round shapes were the most abundant, whereas a significant correlation was found among fruit size with weight and color. The highest fresh weight (597.3 mg), pole diameter (7.1 mm) and equatorial diameter (6.5 mm) were estimated in the pink color fruits.

CONCLUSIONS

The total amount of anthocyanin was higher in red fruits, while the maximum pectin content was obtained in the round white fruits. Overall results must pave the way for a further domestication and introduction of the Chaura species in the agro-productive system in Chile.

Aqueous extraction of pectin from sisal waste

In this work, sisal waste was used as a source of pectin. Sisal is known worldwide as a source of hard fibres, and Brazil is the largest producer of sisal, producing more than 246,000 tonnes. However, the process of removing the fibres of the sisal leaf generates 95% waste. This study investigated the effect of the liquid/solid ratio (%), time (min), and temperature (°C) on the yield of the pectin obtained from sisal waste by attractive environmentally friendly process. A statistical Box-Behnken design was applied to determine the important effects and interactions of these independent variables on the yield of pectin, the dependent variable. Significant models were obtained. The yield of the extracted pectin ranged from 4.61 to 19.2%. The conditions that produced the highest yield (19.2%) were a temperature of 85 °C, extraction time of 60 min and a liquid/solid ratio of 2%.