A preliminary characterization of some pectins from quince fruit (Cydonia oblonga Mill.) and prickly pear (Opuntia ficus indica) peel

Opuntia Ficus-Indica Peel By-Product as a Natural Antioxidant Food Additive and Natural Anticoccidial Drug

The present study was carried out to valorize the Opuntia ficus-indica (OFI) by-products by extracting and identifying their biochemical compounds and evaluating their antioxidant potential by in vitro activities (DPPH radical and FRAP), as well as their capacity to stabilize margarine oxidation (rancimat test). In addition, their in vitro anticoccidial effect on the destruction of Eimeria oocysts isolated from naturally infected chickens was also targeted. Microwaves and response surface methodology tools were used to extract the maximum amount of phenolic compounds (42.05 ± 0.46 GAE mg/g DW of total phenolic compounds in 90 s at 400 watts). Moreover, the effect of extraction factors was also studied. Eight phenolic compounds, including isorhamnetin, dihydrokaempferol, and kaempferol-3-O-rutinoside, were identified. The findings confirmed that OFI peel extract has strong antioxidant activities (DPPH radical, ferric reducing power). The rancimat test shows that OFI peel extract improves margarine stability by 3.2 h. Moreover, it has a notable destruction rate of Eimeria oocysts (30.06 ± 0.51%, LC50: 60.53 ± 0.38 mg/mL). The present investigation offers promise for the reuse of food waste as natural margarine additives, protection of the environment, and substitution of anticoccidial synthetic treatments.

Upcycling Quince Peel into Bioactive Ingredients and Fiber Concentrates through Multicomponent Extraction Processes

This study aimed to promote the total upcycling of quince (Cydonia oblonga Mill.) peel into bioactive extracts (BEs) and fiber concentrates (FCs). The multicomponent extraction processes were optimized using response surface methodology (RSM) coupled with a 20-run experimental design, where the effects of time (1-120 min), temperature (25-95 °C), and EtOH percentage (0-100%) were combined. In addition to the extraction yields, BEs were analyzed for phenolic compounds, organic acids, and other water-soluble constituents, while FCs were characterized for their color and dietary fiber content. Statistically valid theoretical models were obtained by fitting these dependent variables to a quadratic equation and used to predict optimal extraction conditions. Those obtained for phenolic compounds and malic acid were experimentally validated, yielding 9.3 mg/g and 7.6 g/100 g of these bioactive constituents, respectively, and about 51% (w/w) FC. These BEs showed in vitro antioxidant activity and antimicrobial effects against foodborne fungi and bacteria, standing out in some aspects in relation to synthetic food additives, mainly the malic acid-enriched BE. Overall, the developed extraction processes allowed valorizing of quince peel in FCs and BEs that could be used as natural fortifiers or preservatives in the formulation of foods, beverages and dietary supplements.

Chemical Characterization of Different Products from the Tunisian Opuntia ficus-indica (L.) Mill

Various dried (by-)products from the Tunisian O. ficus-indica were elucidated for their proximate composition, fatty acid (FA) composition, inorganic elements, sugars, and polyphenols. Nopal and prickly pear peel and seeds were abundant in fiber (respectively, 28.39, 12.54, and 16.28%). Seeds had also high protein (17.34%) and may be source of an edible oil, due to lipids (9.65%) poor in saturated FAs (14.12%) and rich in linoleic acid (61.11%). Nopal and peel showed the highest levels of Mg (493.57 and 345.19 mg/100 g), K (6949.57 and 1820.83 mg/100 g), Mn (59.73 and 46.86 mg/Kg) and Fe (23.15 and 15.23 mg/Kg), while the fruit pulp predominantly constituted of sugars, glucose and arabinose being predominant (42.57 and 13.56 g/100 g). Total polyphenols widely varied among the Opuntia products (108.36-4785.36 mg GAE/100 g), being mainly represented by hydroxycinnamic and hydroxybenzoic acids, and flavonoids as well. In particular, peel may be revalorized for these valuable bioactives, including 4-hydroxybenzoic acid (484.95 mg/100 g), cinnamic acid (318.95 mg/100 g), rutin (818.94 mg/100 g), quercetin (605.28 mg/100 g), and several isorhamnetin and kaempferol glycosides. Overall, the Tunisian prickly pear cactus could encourage a sustainable production, an effective waste management, and may provide several benefits for human health, in accordance with the model of the Mediterranean diet.

Influence of age on molecular characteristics and rheological behavior of nopal mucilage

Nopal mucilages are of interest due to a variety of potential applications, which include their use as thickeners and rheological modifiers. In this work, changes in molecular characteristics of nopal mucilages with their age and its influence on the rheological behavior of their solutions were analyzed by light scattering, high performance liquid chromatography, a colorimetric method, and linear viscoelastic rheometrical measurements. For this, mucilages obtained from cladodes from Opuntia ficus-indica with different ages, namely 20, 80, and 600 days, respectively, were extracted using water as solvent and then subjected to freeze-drying. The weight-average molecular weight (M w) of the mucilages was found to increase along with the age; meanwhile, the concentration of uronic acids increased and the galactose, rhamnose, and xylose contents decreased. Increasing M w with age resulted in enhanced viscoelastic behavior of solutions, namely, higher viscosity and elasticity at lower mucilage concentrations. Also, along with increasing M w, decrease in neutral sugar contents and increase of pectic compounds (uronic acids) and Ca+ cations in mucilages with age promoted formation of weak gels. Overall, the molecular weights and rheological behaviors reported in this work for nopal mucilages are comparable to those of widely used thickeners such as xanthan and guar gums, which suggest their use in similar applications regarding its age.

Extraction and Characterization of Pectin from Lemon Waste for Commercial Applications

The objective of this paper was preliminary to extract and characterization of purified pectin from lemon wastes. Dry lemon waste was extracted applying citric acid solvent or water at various concentrations under a similar condition (85 ºC for 4 h). It was found that the highest yield of pectin (20.8% dry basis) was achieved using hot water extraction with an esterification degree of 47.8%. It contained 63.2 ± 0.74% galacturonic acid, followed by 17.4 ± 0.76% total sugar. The monosaccharides found in pectin were arabinose (2.7 ± 0.20%), galactose (2.3 ± 0.01%), glucose (1.4 ± 0.09%), mannose (0.4 ± 0.01%), fructose (0.4 ± 0.05%), and xylose (0.1 ± 0.01%). The found pectin had a high atomic weight of 2060 kDa with a wide polydispersity index of 4.41, decided by high-Performance Size Exclusion Chromatography (HPSEC). The extricated lemon waste pectin was grouped into low methoxyl pectin, depends on the methoxyl content and degree of esterification affirmed by Fourier transform infrared spectroscopy (FT-IR) and rheological properties. In conclusion, the discoveries of the study show that lemon waste can be investigated as a promising elective for the commercial manufacturing of pectin.

Optimization of low-fat meat hamburger formulation containing quince seed gum using response surface methodology

In the present study, feasibility of low-fat hamburger production by partial replacement with quince seed gum (QSG) was investigated. The effects of different QSG levels (1.2, 2.4, 3.6, and 4.8 wt%) on cooking loss, water holding capacity, lipid oxidation, antioxidant activity, and hardness of hamburger were investigated during a period of 9 days. The optimization was carried out based on minimum cooking loss, lipid oxidation, and maximum water holding capacity, antioxidant activity, and tissue hardness. Optimum conditions were achieved as 3.26% oil, 4.73% QSG, and 8.25th day of storagability. According to the optimum conditions, values for cooking loss, water holding capacity, lipid oxidation, free radical scavenging, raw hamburger hardness, and fried hamburger hardness were as 13.80%, 55.61%, 0.59 mg MDA/Kg, 48.12%, 2.99 N, and 8.66 N, respectively. Overall acceptability of optimized hamburgers was better and more acceptable than control ones.

Rheological Flow Behavior of Structural Polysaccharides from Edible Tender Cladodes of Wild, Semidomesticated and Cultivated 'Nopal' (Opuntia) of Mexican Highlands

The aim of this study was to quantify the content of polysaccharides of edible tender cladodes (nopalitos) of three species of Opuntia and to evaluate the rheological flow behavior of isolated polysaccharides. A completely randomized experimental design was used to characterize a wild (O. streptacantha), a semidomesticated (O. megacantha) and a domesticated (O. ficus-indica) species. Mucilage content was higher (4.93 to 12.43 g 100 g^-1 dry matter), tightly bound hemicelluloses were lower (3.32 to 1.81 g 100 g^-1 dry matter) and pectins and loosely bound hemicelluloses were not different in wild than in domesticated species. Aqueous solution/suspensions of mucilage, pectins, hemicellulose and cellulose of all species showed non-Newtonian behavior under simple shear flow. The flow behavior of the structural polysaccharides was well described by the Ostwald de-Waele model. Pectins and mucilages exhibited the highest consistency indexes (K values ranged from 0.075 to 0.177 Pasⁿ) with a moderated shear-thinning behavior (n values ranged from 0.53 to 0.67). Cellulose dispersions exhibited the most shear-thinning behavior (n values ranged from 0.17 to 0.41) and hemicelluloses showed a tendency to Newtonian flow (n values ranged from 0.82 to 0.97). The rheological flow properties of these polysaccharides may be useful to improve the textural and sensory qualities of some foods and pharmaceutical materials. Moreover, they can emerge as functional ingredients mainly due to the nutraceutical properties that have been attributed to nopalitos.

Extraction and characterization of three polysaccharides extracted from Opuntia ficus indica cladodes

The chemical extraction and the characterization of polysaccharides from mucilage (MC), pectin (PC) and total pectic mucilage fraction (TFC) of Opuntia ficus indica cladodes as well as the evaluation of their antioxidant activities was investigated. The FTIR spectroscopic analysis revealed the presence of carboxyl and hydroxyl groups corresponding to polysaccharides. Uronic acid and the total sugar contents of PC were higher than those of TFC and MC whereas ash content of MC was considerably more important. In addition, the findings showed that all the samples had little protein content and low average molecular weight compared to the results mentioned in literature. Furthermore, MC reached not only the highest water (WHC) and oil holding (OHC) capacities (7.81g/g and 1.34g/g, respectively) but also the highest antioxidant properties (DPPH and ABTS scavenging activities, β-carotene bleaching inhibition activity and reducing power). However, PC had the strongest emulsifying and foaming properties. As for TFC, it had low WHC, OHC and emulsifying properties whereas it had higher foaming properties than MC and greater antioxidant properties compared to PC. These outcomes can encourage the use of PC as a surfactant and MC and TFC as natural antioxidants in food and pharmaceutical industries.

Extraction, characterization and gelling behavior enhancement of pectins from the cladodes of Opuntia ficus indica

Total Pectins Fraction (TPF) was extracted at room temperature from dried cladodes of Opuntia ficus indica. TPF is constituted of three pectic fractions WSP, CSP and ASP, which are made up of 66.6%, 44.3% and 81.1% (w/w) of galacturonic acid, respectively. The antioxidant ability of TPF increased with the concentration increasing. It scavenged hydroxyl radical by 90% and chelated 90% of ferrous ions at 5 g/L. FTIR study was carried out. Strong characteristic absorption peaks at 1,618 cm(-1) assigned to the vibration of COO(-) group of galacturonic acid. In the fingerprint region, we noticed three well-defined peaks at 1054, 1085, and 1,154 cm(-1) characteristic of pectic polysaccharides. TPF are non-gelling pectins. The co-crosslinking of TPF with carrageenan was carried out and the gelling behavior was successfully improved. Thermo-sensitive hydrogel was obtained with 82% of TPF and 18% of carrageenan (w/w).

Depolymerization of polysaccharides from Opuntia ficus indica: Antioxidant and antiglycated activities

The extraction, purification and degradation of polysaccharides from Opuntia ficus indica cladodes, as well as the evaluation of their antioxidant and antiglycated activities in vitro were investigated. The optimization of the extraction showed that extraction by ultrasound at 40 °C presented the best carbohydrates yield. The degradation of the extracted polysaccharides was achieved by free radical depolymerization with H2O2 in the presence of copper(II) acetate for various reaction times. Sugar contents were determined by colorimetric assays. The macromolecular characteristics of the different isolated and degraded carbohydrates were carried by size exclusion chromatography (SEC/MALS/VD/DRI). These experiments showed that all samples are polysaccharides, which are probably pectins and that molecular weight (Mw) has decreased from 6,800,000 to 14,000 g/mol after 3 h of depolymerization without changing the structure. Preliminary antioxidant and antiglycated tests indicated that degraded polysaccharides for 2 and 3 h showed even better antioxidant and antiglycated activities.

Pectin extraction from quince (Cydonia oblonga) pomace applying alternative methods: effect of process variables and preliminary optimization

The objectives of this study were to introduce alternative methods in the process of pectin extraction from quince pomace, to determine the effect of selected process variables (factors) on the obtained pectin, and to perform a preliminary optimization of the process. A fractional factorial experimental design was applied, where the factors considered were six: quince pomace pretreatment (washing vs blanching), drying method (hot air vs LPSSD), acid extraction conditions (pH, temperature, and time), and pectin extract concentration method (vacuum evaporation vs ultrafiltration). The effects of these factors and their interactions on pectin yield (Y: 0.2-34.2 mg/g), GalA content (44.5-76.2%), and DM (47.5-90.9%), were determined. For these three responses, extraction pH was the main effect, but it was involved in two and three factors interactions. Regarding alternative methods, LPSSD was required for maximum Y and GalA, and ultrafiltration for maximum GalA and DM. Response models were used to predict optimum process conditions (quince blanching, pomace drying by LPSSD, acid extraction at pH 2.20, 80 , 3 h, and concentration under vacuum) to simultaneously maximize Y (25.2 mg/g), GalA (66.3%), and DM (66.4%).

Structural features of pectic polysaccharides from the skin of Opuntia ficus-indica prickly pear fruits

After removal of the mucilage with water at room temperature, pectic polysaccharides were solubilized from Opuntia ficus-indica fruit skin, by sequential extraction with water at 60 degrees C (WSP) and EDTA solution at 60 degrees C (CSP). Polysaccharides with neutral sugar content of 0.48 and 0.36 mol/mol galacturonic acid residue were obtained, respectively, in the WSP and CSP extracts. These pectic polysaccharides were de-esterified and fractionated by anion-exchange chromatography, yielding for each extract five fractions, which were thereafter purified by size-exclusion chromatography. Two of these purified fractions were characterized by sugar analysis combined with methylation and reduction-methylation analysis. The study was then supported by (1)H and (13)C NMR spectroscopy. The results showed that the water-soluble fraction WSP3 and the EDTA soluble fraction CSP3, consisted of a disaccharide repeating unit -->2)-alpha-l-Rhap-(1-->4)-alpha-d-GalpA-(1--> backbone, with side chains attached to O-4 of the rhamnosyl residues. The side chains contained highly branched alpha-(1-->5)-linked arabinan and short linear beta-(1-->4)-linked galactan.