Pectic Extracts Research Articles

Baked mango slices coated with Lactiplantibacillus plantarum immobilized in pectic extracts

The incorporation of probiotic bacteria into plant-based products for the development of functional foods is a challenge because microorganisms must overcome adverse conditions throughout processing, storage and digestive conditions. In this work, baked mango (Mangifera indica L) snacks coated with Lactiplantibacillus plantarum CIDCA 83114 were prepared by immobilizing microorganisms into protective matrices composed of pectins and calcium.To achieve this goal, mango slices were firstly cooked at 90 °C for 60 min. Then, they were coated with suspensions containing pectins extracted from mango peels, microorganisms and calcium and submitted to a moderate time/temperature treatment (50 °C/30 min). The final product, containing 9.38±0.51 log CFU/g snack, was stored at 25 °C for up to 45 days at different relative humidities (RH) (22, 33, 44, 85%) and exposed to simulated digestive conditions. During in vitro digestion assays, probiotic counts were > 7 log CFU/g snack in saliva, gastric, and intestinal stages. Bacterial counts along storage were >6 log CFU/g snack in all the conditions assayed and snacks retained their crispness at RH lower than 33%. The addition of probiotics, pectins and calcium did not cause noticeable changes of color, and snacks were sensorily accepted by consumers. These results support the incorporation of L. plantarum CIDCA 83114 in the formulation of snacks submitted to thermal treatments, retaining an overall acceptability in terms of crispness, and sensory attributes.

Increasing RG-I content and lipase inhibitory activity of pectic polysaccharides extracted from goji berry and raspberry by high-pressure processing

The impact of high-pressure processing (HPP) extraction on the structural, rheological, and functional properties of goji berry and raspberry pectic polysaccharides were investigated under acidic and alkaline conditions. These properties were compared with those of pectic polysaccharides extracted by conventional hot-acid and cold-alkali methods. Extraction yield, molecular weight, rheological behavior, and antioxidant activity of pectic extracts depended on the source materials of extraction. The solvent pH was the driving factor for the degree of esterification, as revealed by NMR and FTIR analysis. Monosaccharide composition was the primary variable between the extracts. The hot-acid extraction led to the highest galacturonic acid (GalA) contents, 46.9% for goji berry and 65.2% for raspberry, indicating the prevalence of homogalacturonans (HG) regions. HPP-assisted acidic/alkaline extractions gave rise to higher rhamnogalacturonan-I (RG-I) regions, pointing to the prevalence of hairy regions. The antioxidant activity of raspberry extracts was significantly (P ≤ 0.05) higher than goji berry extracts. The higher amount of RG-I may determine the higher antioxidant activity of raspberry pectic polysaccharides. The correlation between structural parameters and the lipase inhibitory activity also revealed that the higher lipase inhibitory activity of pectic polysaccharides is mostly correlated with the higher content of RG-I (r = 0.9259, P = 0.00033). Thus, HPP-assisted extraction may intensify the lipase inhibitory activity of pectic polysaccharides by increasing their RG-I content.

Use of a Mexican lime (Citrus aurantifolia Swingle) edible coating to preserve minimally processed mango (Mangifera indica L)

This work aimed to develop an edible coating based on Mexican lime (Citrus aurantifolia Swingle) pectic extract and essential oil on Haden mango (Mangifera indica L.) to extend its shelf life. Mango cubes were coated by immersion in a lime pectic extract (1% pectin w/v), lime essential oil (0.05% v/v), and glycerol (0.7% v/v) solution for 2, 5, and 10 min. Subsequently, coated and uncoated (control) test samples were stored for 21 days, and physical–chemical and microbiological analyses were performed every 3 days. The results showed no significant differences for total soluble solids, pH, and firmness. On the sixth day, bacterial growth was significantly lower in coated mangos than in the control (log 6.08 ± 0.49 and 7.63 ± 0.20 UFC g−1, respectively). The application of the edible coating extended the shelf life of minimally processed mangos by 3 days, delaying physical and chemical changes as well as bacterial growth.

Surfactant-Induced Competitive Displacement of Potato Pectin-Protein Conjugate from the Air-Water Interface.

Potato pectin contains some proteinaceous components and exhibits emulsifying and emulsion stabilizing abilities. The objective of this study was to elucidate the effect of the pectin moiety of the pectin-protein conjugate present in pectic extracts from potato tubers on their interfacial properties. Potato pectin was extracted from highly purified cell wall materials to avoid the contamination of unconjugated proteins. The abilities of the potato pectin to adsorb to graphite surfaces and to resist surfactant-induced competitive displacement from the air-water interface were investigated using atomic force microscopy. The pectin moiety of the potato pectin was capable of adsorbing to graphite surfaces even after alkali treatment. Furthermore, the potato pectin exhibited enhanced resistance to surfactant-induced competitive displacement from the interface as a result of the formation of network structures of self-assembled pectin moieties at the interface. The present results suggest the importance of the pectin moiety with regard to the interfacial properties of potato pectin.

CONCENTRATION AND PURIFICATION OF THE PECTIN EXTRACTS BY ULTRAFILTRATION METHOD

The work is devoted to the study of pectin extracts ultrafiltration using different types of membranes. Pectic extracts are the solutions of high molecular weight polysaccharides (MM from 15 to 50 kDa), which are destroyed in the process of heat treatment in the vacuum evaporating apparature, that leads to a significant deterioration in the quality of pectin. The impurity components in the pectin extract of a low molecular weight, which makes it possible to use ultrafiltration for both concentration and purification from ballast substances, that is very important. The objects of research were pectin extracts obtained from citrus raw materials; the membranes of the type UAM-100 and 200A were used as filter membranes. The results of the study have been shown, that the use of UAM-100 membranes in a stationary cell allows to remove up to 20% of the solution within 20 minutes, and with - stirring up to 27%. The use of membranes with large openings (up to 200 A) makes it possible to activate the process of the separation and concentration of pectin extracts: the degree of concentration reaches up 45%, the content of solids in the concentrate increases up to 7.6%, and the content of pectin to up 6.4%, that is in 1,7 times. However, the loss of low molecular weight pectin in the filtrate is about 4%. A comparative analysis of the results of research has shown a high productivity with the use of the capron membrane 200A, as well as on the qualitative parameters of the pectins, released from the concentrates, the higher parameters for the uroconid component, molecular weight, pectin jelly strength and complexing ability were noted for pectins isolated using the UAM- 100 membrane.

Physico-chemical characterization of water-soluble pectic extracts from Rosa damascena, Calendula officinalis and Matricaria chamomilla wastes

Water soluble pectic extracts were obtained from industrial wastes of three essential oil plants–Rosa damascena (rose), Calendula officinalis (marigold) and Matricaria chamomilla (camomile) as novel approach for valorization of these residues. The higher yield was observed for pectic extract isolated from waste rose petals–11%. Their chemical composition was investigated and was found that rose and marigold polysaccharides were medium methoxylated (DM around 50%) and camomile was low-methoxyl pectic extracts. The three pectic extracts had galacturonic acid content more than 50%. The lowest surface tension value showed pectic extract isolated from camomile wastes and it was comparable with beet and butternut pectins, guar and locust bean gums. The emulsifying properties (50% oil in water emulsions) of the isolated extracts were investigated. It was found that camomile pectic extract emulsions had the highest mechanical stability and marigold pectic extract derived emulsions were the least influenced by the storage temperatures. The data from differential thermal analysis (DTA) showed that the polysaccharide extracts were thermally stable until 220 °C. To our knowledge this is the first attempt for utilization of camomile and marigold wastes as source of pectic extracts and characterization of physico-chemical properties of water-soluble pectic extracts obtained from Rosa damascena, Calendula officinalis and Matricaria chamomilla residues.

Antibacterial activity of pectic-based edible films incorporated with Mexican lime essential oil

Edible films have been used as carriers of foods additives such as antioxidant or antimicrobial agents. Lime essential oil has demonstrated to act as an antimicrobial agent on food systems which can be incorporated into a film matrix. In this research edible films were prepared with two different raw matters, lime bagasse pectic extract and lime pomace pectic extract at 0.70, 0.85 and 1.00% pectin equivalents. Mexican lime essential oil was incorporated to a film-forming solution at 0, 500 and 1000 mg L−1 and 0.70% glycerol was added as plasticizer. Edible films antibacterial activity against food-borne pathogenic bacteria (Escherichia coli O157:H7, Salmonella Typhimurium, Bacillus cereus, Staphylococcus aureus and Listeria monocytogenes) was investigated by the disc diffusion method, with zones of inhibition measured after 24 h of incubation. The higher inhibition zone was against E. coli (20.6 ± 1.17 mm). Edible films prepared with pectic extracts (Mexican Lime bagasse and pomace) presented higher inhibition against Gram negative bacteria, but those prepared with bagasse pectic extract were more effective against all five bacteria studied. Pectic extracts edible films incorporated with Mexican lime essential oil inhibited the growth of foodborne pathogenic bacteria and can be useful in the preservation of food to increase shelf life.

Assessment of antiproliferative activity of pectic substances obtained by different extraction methods from rapeseed cake on cancer cell lines.

In this work the antiproliferative activity of pectic substances obtained by different extraction methods from defatted rapeseed cake was assessed on cancer cell lines. The process consisted of sequential treatment with alkalized water (pH∼8), EDTA (0.01 M), alkaline protease (Alkalase 2.4L) and a commercial pectinase preparation (Viscozyme L or Pectinex Ultra SP-L). Pectic extracts identification was performed using spectroscopy and chromatography techniques. FT-IR and HPLC-IR results suggest that the neutral pectic extracts produced would be arabinogalactans and β-galactans. All the pectic substances extracted (acid and neutral) from RSC exhibited antiproliferative activity, being more effective on MCF-7 cells than Caco-2. The most effective pectic extract was obtained by Alkalase 2.4 L which killed over 80% of MCF-7 cells and 60% of Caco-2 cells. At less than 10 mg/mL pectic extracts enriched in neutral sugars also exhibited antiproliferative activity (50 and 40%, respectively), which was superior to the modified citric pectins activity at the same concentration for the breast cancer cell line (61.6% for MCF-7 and 49.9% for Caco-2 cells). These results show that the antiproliferative activity depends on both the type of pectin (acid or neutral) and the extraction procedure.

Screening of antioxidant activities of polysaccharides extracts from endemic plants in Gabon

The usage of plants as food, cosmetics or medicinal products is common throughout the world, particularly in the traditional medicines of Africa, Asia, and South America. Despite this long-standing use, many properties of plant constituents, including their capacity to inactivate reactive oxygen species, remain unknown today. In this context, polysaccharides were isolated from barks, leaves or stems of endemic plants of Gabon by sequential extractions of crude cell walls with oxalate and KOH. Analysis of fractions indicated that pectic extracts are mainly composed of HG and RG-I in various proportions whereas hemicellulose fractions are composed of both XXXG-type xyloglucans and (1,4)-xylans substituted by 4-O-Me GlcUA residues. Antioxidant activities of these plant extracts were evaluated by monitoring their free radical scavenging activity of 2-2-diphenyl, 1-picrylhydrazyl, iron reducing capacity and metal chelating activity. Pectin from four extracts presented antioxidant activity in the DPPH assay compared to ascorbic acid (AA). These extracts also exhibited high ferric iron reducing powers compared to AA but low ferrous ion-chelating properties compared to EDTA. These activities were concentration-dependent. In contrast, commercially available pectins, xyloglucan and arabinoxylan were found to be inactive in both assays. The free scavenging activity of these molecules disappeared after enzymatic digestion and saponification, whereas the iron reducing power partially remains after these two treatments. The fact that all pectins and hemicelluloses from the three plants reacted differently suggests that specific structural motifs are involved for generation of antioxidant activity

Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer cell line

In the last years, sugar beet pectins have been the subject of several investigations involving extraction methodologies, chemical composition and functional properties. The structure of pectins, which depends on the extraction method, is decisive in their capacity to induce apoptosis on several cancer cell lines like colon, prostate and breast. In this work, sugar beet pectin extraction was performed in the following steps: lipid extraction with hexane, removal of soluble complex carbohydrates and proteins, and enzymatic treatment with amyloglucosidase, protease, and pectinase. The enzymatic treatment was carried out with Rohapect DA6L under the following conditions: 50°C, pH 4.0, 2% enzyme/substrate (E/S) ratio, 15 h, and a solid to liquid ratio of 1 : 10. The pectic extract showed a degree of polymerization (DP) profile of 55.8% with DP ⩾ 7; 4.9% with DP6; 5.8% between DP2 and DP6 ; 4.7% with DP2; and 28.8% with DP1. The pectic extract was examined for its antiproliferative activity on the MCF-7 breast cancer cell line. At a concentration range of 12.5–25 mg/mL the pectic extract killed 80.6% of the cells, exhibiting a higher antiproliferative activity than 4-hydroxytamoxifen (4-OHT), a classical anticancer drug, which killed 56.5% of the cells.

COMPARATIVE EXTRACTION OF PECTIC AND POLYPHENOLS FROM MEXICAN LIME POMACE AND BAGASSE

Mexican lime bagasse and pomace are rich in pectin and they also represent an important source of value-added compounds such as polyphenols. Two different options for the combined recovery of pectin and phenolic compounds from Mexican lime bagasse and pomace, two byproducts of industrial lime processing, were developed. Conventional and microwave-assisted extraction methods were used. All pectic extracts presented a degree of esterification in the range of 70%. Pomace extracts had the higher pectin yield and the lower polyphenol content. Among the bioactive compounds identified by HPLC were two flavonones, naringin and hesperidin, all compounds were present in low concentration in the pectic extracts. Microwave pectic extracts presented depolymerization, as observed by molecular weight determination (12 KDa) and compared against conventional pectic extracts which presented a molecular weight of 670 KDa. The film forming capacity of pectic extracts was also evaluated. Antioxidant activity of pectic extracts was also assessed by three different methods; all extracts showed a better activity in Fe2+ chelating assay (62.85-73.32%) and lipid oxidation inhibition (63.07-72.28%) than in DPPH radical inhibition (5.32-6.65%). These findings indicate a correlation between the amount of phenolic compounds and the antioxidative capacity. Conventional pectic extracts from Mexican lime bagasse and pomace presented bioactive compounds with potential application for edible films and coatings in food industry.

Alterations in cell wall polysaccharides during ripening in distinct anatomical tissue regions of the fig (Ficus carica L.) fruit

Abstract During the last stage of fig ( Ficus carica L.) fruit development, profound cell wall modification processes occur as indicated by increase in fruit size and tissue softening. In this study, we characterized the changes in cell wall polysaccharides taking place within the distinct and separate tissues of the receptacle and the pulpy drupelets during sequential ripening in fig fruit. The pectic extracts had high uronic acid contents in addition to high amounts of Ara, Gal and Rha. The gel filtration profile of the water-soluble polymers at the ripening onset in drupelets were different when compared to those of the receptacle, even though in both tissues, these polymers underwent increased solubilization and depolymerization during ripening. The molecular downshift of the CDTA-soluble polymers and the decrease in the amounts of both the uronic acid and total sugars were more pronounced in the drupelets than in the receptacle. Major difference in the neutral sugar composition between the two tissues was only observed in the Na 2 CO 3 -soluble fraction. The xyloglucan polymers in 4% KOH fraction exhibited a molecular size downshift accompanied by a decline in Xyl and increase in Glc. In the 24% KOH fractions of both tissues, the total sugar and xyloglucan components decreased in amount and also exhibited a molecular size downshift during ripening. These data suggest that even though quantitative and qualitative changes in cell wall polysaccharides occurred during ripening in both tissues, qualitative variations between tissues occurred only in the pectic polymers but not in the hemicellulosic polymers.

Calcium-mediated gelation of an olive pomace pectic extract

Pectic raw material was extracted from the alcohol insoluble residue of olive pomace. After purification, the olive pectic extract (OPE) contained 48% of galacturonic acid (GalA) and 31% of arabinose, in a total sugar content of 72%, and a degree of methylesterification (DM) of 43%. Phase diagrams were established to define the physical state of the OPE/calcium systems, at pH 3 and 7, as a function of GalA and calcium concentration. The rheological properties of the OPE/calcium systems were investigated by small-amplitude oscillatory tests. Kinetics of gel ageing and the viscoelastic properties of the cured gels were evaluated as a function of GalA and calcium concentration at pH 3 and 7. Compared with the observed behaviour of a citrus pectin, taken as representative of a commercial low-methoxyl pectin, the OPE showed higher critical GalA and calcium concentrations for gelation to occur, a larger region corresponding to homogeneous gel, and gels characterised by lower viscoelastic moduli, at similar GalA and calcium concentrations.

Analysis of retted and non retted flax fibres by chemical and enzymatic means

Flax fibres ( Linum usitatissimum L.) were subjected to chemical and enzymatic analysis in order to determine the compositional changes brought about by the retting process and also to determine the accessibility of the fibre polymers to enzymatic treatment. Chemical analysis involved subjecting both retted and non retted fibres to a series of sequential chemical extractions with 1% ammonium oxalate, 0.05 M KOH, 1 M KOH and 4 M KOH. Retting was shown to cause minimal weight loss from the fibres but caused significant changes to the pectic polymers present. Retted fibres were shown to have significantly lower amounts of rhamnogalacturonan as well as arabinan and xylan. In addition the average molecular mass of the pectic extracts was considerably lowered. Enzyme treatment of the 1 M KOH extracts with two different enzymes demonstrated that the non retted extract contained a relatively high molecular weight xylan not found in the retted extract. Treatment of the 1 M KOH extracts and the fibres with Endoglucanase V from Trichoderma viride demonstrated that while this enzyme solubilised cellulose as well as xylan and xyloglucan oligomers from the extract, it had limited access to these polymers on the fibre. MALDI-TOF MS analysis of the material solubilised from the extract suggested that the xylan was randomly substituted with 4-O-methyl glucuronic acid moieties. The xyloglucan was shown to be of the XXXG type and was substituted with galactose and fucose units. The enzyme treatments of the fibres demonstrated that the xylan and xyloglucan polymers in the fibres were not accessible to the enzyme but that material which was entrapped by the cellulose could be released by the hydrolysis of this cellulose.

Extraction and Colorimetric Quantification of Uronic Acids of the Pectic Fraction in Fruit and Vegetables

The total pectic content of a selection of fruits and vegetables was studied using a spectrophotometric method developed for the determination of uronic acids in biological fluids. This method was used on pectic extracts obtained from food samples after most of the components that produce interference was removed. The preliminary extraction process varied with the food analyzed. The pectic fraction was quantified using a phenolic reagent (m-hydroxydiphenyl) specific for uronic acid which did not interact with the sugars present in the sample. The validation study showed a recovery rate of 82 ± 3.8 to 95 ± 2.5%, which was considered acceptable for such a complex extractive process. Mean sensitivity was 2.89 mg/ml. Analysis of a standard range of galacturonic acid concentrations (0.0125–0.1 mg/ml) yielded linear results. The intraassay and interassay coefficients of variation were 3.9 to 6.2 and 2.4 to 3.0%, respectively. Use of the method on a variety of fruit and vegetable samples confirmed its effectiveness.

Fixed-bed purification of ferulic acid from sugar-beet pulp using activated carbon: Optimization studies

Selective binding on a wood-based, chemically-activated carbon was considered following extensive enzymic hydrolysis of a sugar-beet pulp pectic extract. Adsorption and ethanolic elution were investigated, aiming at quantitative extraction and recovery of the released ferulic acid, at minimal cost and according to a given production rate. The effects of key operating parameters on the required amounts of adsorbent and eluent were assessed, and the prerequisites for optimal management of successive cycles were identified. Competition effects were analyzed, with special attention to residual feruloylated oligosaccharides. Complete saturation before regeneration was shown to yield the highest adsorption selectivity, desorption efficiency and purity of ferulic acid (∼50%). Crystallization from the eluate was achieved, allowing further purification of this phenolic compound for applications as a bioactive antioxidant or as a flavour precursor.

The effect of various citrus waste fractions on xanthan fermentation

Four different media of citrus waste origin were compared as substrates for xanthan fermentation: whole citrus waste, pectic, hemicellulosic and cellulosic extracts. It was found that Xanthomonas campestris utilized in parallel both simple and complex carbon compounds originating from citrus wastes. The substrate utilization rate in the medium based on pectic extract was similar to that in the medium based on whole citrus waste. In addition, pectic extract of citrus waste yielded the same amount of xanthan as whole citrus waste. This indicates that water soluble substances in citrus waste such as pectins, organic acids and simple carbohydrates are readily converted into xanthan and that their contribution to xanthan production is higher than that of the other constituents of citrus waste. The biodegradability of the hemicellulose and cellulose extracts of citrus waste was found to be much lower than that of the pectic extract. Substrate utilization and its conversion to xanthan in the hemicellulosic extract was 36% lower, and in the cellulosic extract 60% lower, than those in the whole citrus waste.

Xanthan fermentation of citrus waste

Four different fractions of citrus waste were compared as substrates for xanthan fermentation: whole citrus waste, pectic, hemicellulosic and cellulosic extracts. The whole waste was found to be a good substitute for glucose media for xanthan production. Xanthomonas campestris utilized both simple and complex carbon compounds originating from citrus wastes. Substrate utilization in the medium based on pectin extract was similar to that in the medium based on a whole citrus waste and the pectic extract yielded the same amount of xanthan as the whole waste. This indicated that watersoluble substances in citrus waste such as pectins, organic acids and simple carbohydrates were readily converted into xanthan and that they were the main contributor to xanthan production from the whole waste. The biodegradabilities of the hemicellulose and cellulose extracts were found to be much lower than that of the pectic extract.

The use of a new, rapid micro-method for analysing changes in the carbohydrate fractions of potato tuber tissue after invasion by phytophthora infestans

The development of a rapid micromethod for separation and estimation of carbohydrate fractions of potato tuber tissue allowed a re-examination of certain changes following the invasion of thin tissue discs by Phytophthora infestans. Invasion is followed by a considerable depletion in 80% ethanol-soluble carbohydrate, and a lesser depletion of starch levels. A “pectic extract” isolated by treatment with alkali followed by a P. infestans glycosidase preparation, showed decreases by comparison with uninoculated tissue, but the decreases were more marked when the proportion of this fraction hydrolysed by the fungal glycosidases was examined. As expected the final residue of the extraction sequence showed greater increases in infected discs. The relation of these changes in the pathogenic interaction is discussed.