Pectin Acid Research Articles

Natural deep eutectic solvents pretreatment as an aid for pectin extraction from apple pomace

Three natural deep eutectic solvents (NADES; choline chloride (CC): lactic acid (LA), CC: oxalic acid (OA), CC: urea (U)) in the ratio 1:2 were tested as a pretreatment of apple pomace prior to hot water extraction of pectin. The pretreatment duration and temperature (for 0.5–2h, at 40–80 °C) was adjusted to limit cell wall polysaccharides losses and degradation. Extraction yields and sugar composition were used to evaluate the impact of the pretreatment on pectin extraction and the molecular weight and degree of esterification of pectin were characterized. Results showed that CC:LA and CC:U pretreatments led to close overall recovery yields with the control using water instead of NADES. Instead, CC:OA led to polysaccharides degradation and loss. The cell wall monosaccharides composition was affected after CC:LA and CC:U pretreatments at 60 °C and above, while it was preserved by CC:LA pretreatments at 40 °C for 1h. Moreover, CC:LA pretreatment facilitated hot water extraction of a large amount (33.1%–56.1% of uronic acid recovery) of high Mw HM pectin comparable with pectin obtained through classical method. CC:U pretreatment led to saponification and affected pectin composition by introducing choline. Thus, CC:LA pretreatment of apple pomace followed by water extraction offers a “green” alternative for mineral acid pectin extraction while CC:U allows functionalizing pectin in apple pomace prior to hot water extraction.

Characterization of an acidic pectin methylesterase from Paenibacillus xylanexedens and its application in fruit processing

A pectinase-producing bacterial isolate, identified as Paenibacillus xylanexedens SZ 29, was screened by using the soil dilution plate with citrus pectin and congo red. A pectin methylesterase gene (Pxpme) was cloned and expressed in Escherichia coli. The gene coded for a protein with 334 amino acids and a calculated molecular mass of 36.76 kDa. PxPME showed the highest identity of 32.4% with the characterized carbohydrate esterase family 8 pectin methylesterase from Daucus carota. The recombined PxPME showed a specific activity with 39.38 U/mg against citrus pectin with >65% methylesterification. The optimal pH and temperature for PxPME activity were 5.0 and 45 °C. Its Km and Vmax value were determined to be 1.43 mg/mL and 71.5 μmol/mg·min, respectively. Moreover, PxPME could increase the firmness of pineapple cubes by 114% when combined with CaCl2. The acidic and mesophilic properties make PxPME a potential candidate for application in the fruit processing.

The Role of Brachypodium distachyon Wall-Associated Kinases (WAKs) in Cell Expansion and Stress Responses.

The plant cell wall plays a critical role in signaling responses to environmental and developmental cues, acting as both the sensing interface and regulator of plant cell integrity. Wall-associated kinases (WAKs) are plant receptor-like kinases located at the wall—plasma membrane—cytoplasmic interface and implicated in cell wall integrity sensing. WAKs in Arabidopsis thaliana have been shown to bind pectins in different forms under various conditions, such as oligogalacturonides (OG)s in stress response, and native pectin during cell expansion. The mechanism(s) WAKs use for sensing in grasses, which contain relatively low amounts of pectin, remains unclear. WAK genes from the model monocot plant, Brachypodium distachyon were identified. Expression profiling during early seedling development and in response to sodium salicylate and salt treatment was undertaken to identify WAKs involved in cell expansion and response to external stimuli. The BdWAK2 gene displayed increased expression during cell expansion and stress response, in addition to playing a potential role in the hypersensitive response. In vitro binding assays with various forms of commercial polysaccharides (pectins, xylans, and mixed-linkage glucans) and wall-extracted fractions (pectic/hemicellulosic/cellulosic) from both Arabidopsis and Brachypodium leaf tissues provided new insights into the binding properties of BdWAK2 and other candidate BdWAKs in grasses. The BdWAKs displayed a specificity for the acidic pectins with similar binding characteristics to the AtWAKs.

The D-galacturonic acid catabolic pathway genes differentially regulate virulence and salinity response in Sclerotinia sclerotiorum

Sclerotinia sclerotiorum causes white mold disease on a wide range of economically important crops such as soybean, canola, tomato, pea and sunflower. As one of the most successful plant pathogens, S. sclerotiorum has the unique ability of adapting to various environmental conditions and effectively suppressing or evading plant defense. Notably, S. sclerotiorum secretes an array of plant cell-wall degrading enzymes (CWDEs) to macerate host cell wall and utilizes the liberated monosaccharides and oligosaccharides as nutrients. One of the major plant cell wall constituents is polygalacturonic acid in pectin, with D-galacturonic acid being the most abundant component. In this research, we identified four S. sclerotiorum genes that encode the enzymes for the D-galacturonic acid catabolism, namely Ssgar1, Ssgar2, Sslgd1 and Sslga1. Gene-knockout mutants were created for all four catabolic genes. When cultured on pectin as the alternative carbon source, Sslgd1- and Sslga1-deletion mutants and Ssgar1/Ssgar2 double deletion mutants exhibited significantly reduced growth. The D-galacturonic acid catabolic genes are transcriptionally induced by either polygalacturonic acid in the culture media or during host infection. Virulence tests of the knockout mutants revealed that Ssgar2, Sslgd1 and Sslga1 all facilitated the effective colonization of S. sclerotiorum to the leaves of soybean and pea, but not of tomato which has the lowest D-galacturonic acid contents in its leaves. In addition to their positive roles in virulence, all four enzymes negatively affect S. sclerotiorum tolerance to salt stress. SsGAR2 has an additional function in tolerance to Congo Red, suggesting a potential role in cell wall stability of S. sclerotiorum. This study is the first report revealing the versatile functions of D-galacturonic acid catabolic genes in S. sclerotiorum virulence, salinity response and cell wall integrity.

Sugar beet pectin extracted by ultrasound or conventional heating: a comparison.

The yield and quality of sugar beet pulp pectin obtained by ultrasound-assisted extraction (UAE) were compared to those obtained by conventional heating. Extraction temperature (70-90)°C, extraction time (2-4) h and pH (1-1.5) were considered as the variables for the conventional extraction while ultrasound frequency (20-60) kHz, time (10-30) min and amplitude (60-100%) were considered as the variables for UAE. The optimal conditions for maximum yield of pectin for conventionally and ultrasonically extracted pectin were determined by the central composite design and the Box Behnken design, respectively. The optimum conditions of conventional extraction were the temperature of 90°C, time of 4h and pH of 1. The optimum conditions of UAE were ultrasound frequency of 20kHz, time of 10min, and ultrasound amplitude of 96%. Extraction using the optimized conditions of conventional heating and UAE achieved the best yield of 20.75% and 20.85%, respectively. The degree of methyl esterification, ferulic acid content and molecular weight of UAE pectin were higher than conventionally extracted pectin but the content of galacturonic acid in UAE pectin was lower than that of conventionally extracted pectin. The infrared spectra of both pectins revealed the occurrence of polysaccharide component. The pectin achieved by UAE had higher lightness value than conventionally extracted pectin, confirming its application in different products partially in bright food products. The UAE pectin possessed higher viscosity than conventionally extracted pectin. The addition of UAE pectin increased all of the DSC gelatinization parameters. Overall, UAE could be a promising scalable and economical approach to obtain pectin with unique characteristics.

Formulation and characterization of the quality parameters of jellies and candy pastes of purple pitanga (Eugenia uniflora L.) with reduced sugars

The objective of the present work was to characterize and microbiologically evaluate different formulations of jams and paste candies of purple pitanga with reduced sucrose contents. The formulations made for jams were “jam A” with a 100% proportion and “jam B” with a 50% proportion, all with the addition of pectin (1.5 g) and citric acid (0.45 g). For the paste candies the concentrations were “candy A” with 60% and “candy B” with 40%, all added with citric acid (0.6 g) and water (36 mL). The elaboration process followed all the quality control standards and, in sequence, the physicochemical (humidity; ash content; soluble solids; pH; titratable acidity; sugars; color parameters; anthocyanins; flavonoids) and microbiological (total and thermotolerant coliforms; molds and yeast; coagulase positive Staphylococcus and Salmonella sp.) characterizations were performed. The results of the analyses have been compare only between formulations of the same type of product. All physicochemical data were within the standard parameters for candies and jams. As for the color aspect, the samples showed a characteristic intense red, differing only in the chromaticity and luminosity parameters in sweets and jellies respectively. The pitanga by-products presented varied concentrations of bioactive compounds, with emphasis on greater amounts of anthocyanin. For all microbiological aspects evaluated, the results were in accordance with the standards established by the legislation. Thus, the possibility of the development of purple pitanga jams and candies has been showned, with a reduction in sucrose content, but with interesting nutritional, microbiological and visual characteristics.

Optimization of extraction with salicylic acid, rheological behavior and antiproliferative activity of pectin from Citrus sinensis peels

A Box-Behnken design was used to optimize extraction temperature, extraction time and concentration of the salicylic acid to obtain a maximum polysaccharide yield from Citrus sinensis peels. The optimal settings were: extraction time 3 h, extraction temperature 80 °C and concentration of the salicylic acid 1.5%. Under these conditions, the experimental yield and uronic acid content were 11.74% and 66.9% respectively. Preliminary characterization was performed via FT-IR, SEC/MALS/VD/DRI and GC–MS after hydrolysis. SEC analysis showed that the extracted polysaccharide had a weight average molar mass of 350 kDa and an intrinsic viscosity of 640 mL/g. The GC–MS results revealed that the extracted polysaccharide was composed of arabinose 56.7%, galactose 17.8%, xylose 13.8%, rhamnose 5.1%, mannose 2.5% and glucose 1.5% suggested a rhamnogalacturonan pectin type I with a degree of esterification of 50.9% (IRTF). The flow curve and the dynamic frequency sweep were obtained at 10, 20, 30 and 40 g/L in water and at 30 g/L in presence of CaCl2 or NaCl at 1 mol/L. The solutions showed shear-thinning behavior fitted with Ostwald-De Waele model, except 10 g/L with a Newtonian behavior. The apparent viscosity and, the G’ and G” moduli increase with PACO concentration in agreement with a slow-down of the dynamic chain. In the presence of CaCl2 or NaCl the reduction of electrostatic repulsions between pectin chains decreases the rheological parameters. The effect is less sensitive with CaCl2 due to intermolecular interactions. The antiproliferative activity of the extracted pectin on human Caco-2 and Hep-2 cells was very interesting with an IC50 1.4 and 1.8 μg/mL respectively.

Utilization of the co-product of jaboticaba (Myrciaria jaboticaba Berg.) for pectin extraction

Pectin is a polysaccharide that can be applied to various food industry products to modify the viscosity of food. The objective of this work was to optimize the extraction of pectin of jabuticaba peel by modificating the yield, galacturonic acid content (AUA), esterification content (DE), pectin content (P), and neutral sugars (N). The experiment was performed using the technique of factorial planning of complete experiments and surface response analysis. The extraction can be reported through factorial planning with coefficients of determination (R²) of 0.92, 0.91, 0.89, 0.88 and 0.90 for the yield extraction, AUA, DE, P, and N, respectively. The content of AUA ranged from 22.82 to 65.35%, the DE varied from 26.72 to 77.50%, the percentage of P found in the extraction 25.50 to 66.12%. The best performance was verified utilizing the following parameters: extraction time less than 75 min, temperature of 70°C, and citric acid concentration of 0.75 mol.L-1.

Polymer or microgel particle: Differences in emulsifying properties of pectin as microgel or as individual polymer chains

The differences and similarities in the emulsion stabilising behaviour of pectin as individual polymer chains or as pectin-based microgels (particulate polymer network) were investigated. To compare the emulsifying properties and the adsorption mechanism, oil-in-water emulsions were produced with either pectin as individual polymer chains or as pectin-based microgels. The droplet size distribution of polymer stabilised emulsions varied depending on the used pectin type (apple and citrus pectin or pectinic acid). However, when microgel particles were used, the droplet size distribution remained constant, regardless of the pectin type. Further investigations were conducted with pectinic acid, due to comparable emulsification results when used as individual polymer chains or as microgel particle. Interfacial tension measurements revealed that microgel particles made from pectinic acid do not affect the oil-water interfacial tension, whereas pectinic acid as individual polymer chains decreases its value. This shows that microgels prepared with pectinic acid stabilise emulsions with a completely different mechanism than pectinic acid as individual polymer chains. The effect of the homogenising pressure difference on the droplet size distribution was investigated to gain further insight into the stabilizing mechanism. Emulsions stabilised with pectinic acid as individual polymer chains showed increased coalescence with increasing pressure difference, whilst emulsions stabilised with pectinic acid as microgel particles were not affected by an increase in the pressure difference. The gained knowledge can help to choose suitable process and formulation parameters for applications in which pectin is used as an emulsifier, whether as an individual polymer chain or as a microgel particle. For example, when high homogenisation pressure differences are required, microgel particles are more suitable than pectin as individual polymer chains, due to the low oil droplet coalescence. On the other hand, when high concentrations of emulsifying agent is required, pectin as individual polymer is the more appropriate choice.

Waste to wealth: optimizing novel pectin acid extraction from honeydew (cucumis melo l. var. inodorous) peels as a potential halal food thickener

Pectin is found to be widely used as additives in food, pharmaceutical and cosmetic industries. This study was carried out using a conventional acid extraction method. The influences of different acid reagents used (citric acid and nitric acid), extraction time (30, 45 and 60 min) and temperature (60, 70 and 80°C) towards the extraction yield and its degree of esterification (DE) of pectin from Cucumis melo L. var. inodorous peels being investigated. Citric acid gives the maximum yields of pectin (35.26%) under optimum condition at 80°C and 60 min. Extraction time and temperature were significantly (p>0.05) affected the amount of pectin yields, whereby the optimum condition for both acids was at 80°C and 60 min. The degree of esterification (DE) of the isolated pectin in this study was 50.38 % and 59.88 % respectively for citric acid and nitric acid where this pectin was considered as high methoxyl pectin (HMP). From the color analysis, the value for ‘L’, ‘a’ and ‘b’ for citric and nitric acid were significantly different (p>0.05) between each other. Citric acid has a lighter color of pectin extract which is preferable to be commercialized. Pectin from honeydew waste is a novel food ingredient in Malaysia and could be as an excellent alternative for replacing gelatin in food industry applications and other non-food potential interventions.

Isolation and Characterization of Pectin from Waste of “Raja Nangka” Banana Peels (Musa acuminata (AAA cv))

Raja nangka banana peel contains pectin (10-21%), lignin (6-12%), and galacturonic acid. Pectin is a D -galacturonic acid polymer which connected with the β -1,4-glycosidic bond. Pectin was benefitted a gel form material and thickener making jam and low-calorie food. Pectin was generated with an isolation process. The purpose of this research was isolated and characterized pectin from raja nangka banana peel waste, and then pectin was obtained characterized for know pectin quality. Pectin isolation was done with the reflux extraction method. Pectin extraction uses chloric acid 1 N solvents. Pectin isolation was done at pH 1,5 temperature 90 ° C for 80 minutes. The purpose of testing for the function group was known as groups in pectin isolation. The functional group in pectin was got and then characterized with FTIR to show group vibration OH, CH 3 , C=O, C-H-, and R-O-R, with a wavelength respectively 3.448,366; 2.930,022; 1649,310; 1385,247 and 1146,453. Other than, pectin physical nature was done such as water content (0,061%), ash content (1,994%), equivalent weight (748,29%), methoxyl content (6,90%), galacturonic acid (250,88%) and esterification degree (0,0156%). Pectin characterization was got correct with pectin quality standard based on IPPA (International Pectin Producers Association).

PRPs localized to the middle lamellae are required for cortical tissue integrity in Medicago truncatula roots.

A family of repetitive proline-rich proteins interact with acidic pectins and play distinct roles in legume root cell walls affecting cortical and vascular structure. A proline-rich protein (PRP) family, composed of tandemly repeated Pro-Hyp-Val-X-Lys pentapeptide motifs, is found primarily in the Leguminosae. Four distinct size classes within this family are encoded by seven tightly linked genes: MtPRP1, MtPRP2 and MtPRP3, and four nearly identical MtPRP4 genes. Promoter fusions to β-glucuronidase showed strong expression in the stele of hairy roots for all 4 PRP genes tested, with additional expression in the cortex for PRP1, PRP2 and PRP4. All except MtPRP4 are strongly expressed in non-tumorous roots, and secreted and ionically bound to root cell walls. These PRPs are absent from root epidermal cell walls, and PRP accumulation is highly localized within the walls of root cortical and vascular tissues. Within xylem tissue, PRPs are deposited in secondary thickenings where it is spatially exclusive to lignin. In newly differentiating xylem, PRPs are deposited in the regularly spaced paired-pits and pit membranes that hydraulically connect neighboring xylem elements. Hairpin-RNA knock-down constructs reducing PRP expression in Medicago truncatula hairy root tumors disrupted cortical and vascular patterning. Immunoblots showed that the knockdown tumors had potentially compensating increases in the non-targeted PRPs, all of which cross-react with the anti-PRP antibodies. However, PRP3 knockdown differed from knockdown of PRP1 and PRP2 in that it greatly reduced viability of hairy root tumors. We hypothesize that repetitive PRPs interact with acidic pectins to form block-copolymer gels that can play distinct roles in legume root cell walls.

Aluminum toxicity-induced pollen tube growth inhibition in apple (Malus domestica) is mediated by interrupting calcium dynamics and modification of cell wall components

Aluminum (Al) is known the most abundant metal in the Earth’s crust which is a major problem limiting crop production and yield throughout the world. Al could inhibit pollen tube elongation, however the mechanism is largely unknown. The aim of this study was to investigate the influence of Al toxicity on Malus domestica pollen tube growth and possible cytological mechanism. The results showed that Al inhibited pollen germination and tube growth in a concentration dependent manner. An non-invasive ion-selective electrode technique together with fluorescent labeling indicated that Al toxicity decreased pollen tube apex calcium influx and disrupted [Ca2+]c gradient. Al toxicity also altered actin filament orientation. Results from immuno-localization and fluorescence labeling indicated that Al toxicity affected the accumulation and distribution of callose, acid pectins, esterified pectins and arabinogalactan proteins in pollen tubes, which were supported by Fourier-transform infrared analysis. In a word, Al induced a series of the cellular toxic changes concerning calcium influx, [Ca2+]c gradient, actin and cell wall components. Based on the information provided in this article, it is concluded that Al toxicity inhibits apical growth of pollen tubes by changing calcium influx and [Ca2+]c and cell wall components.

Application of Pectin Extracted from Cocoa Pod in the Production of Edible Film

Cocoa pod is lignocellulosic waste which contain cellulose, hemicellulose, lignin, pectin and other compounds. Pectin is a polymer of D-galactaconic acid linked by an α-1,4 glycoside bond. Some carboxyl groups in pectin compounds undergo esterification with methyl (methylation) to methoxyl groups. This compound is referred to as pectinic acid or pectin. Pectin in cocoa pod can be produced by extraction. The purpose of this research is to know the physical and chemical characteristics of pectin-based edible film from cocoa pod. This research is conducted in two steps. The first stage is the extraction of pectin from cocoa pod, and the second stage is the process of making edible film. Pectin extraction was performed by using 5% citric acid. The extracted pectin will be made into an edible film using glycerol as plastisizer. The glycerol treatments are 0%, 2%, 4%, 6%, 8%. The design used was Completely Randomized Design (CRD) at 5% significant level. The results showed that the addition of glycerol has significant effect on water content, thickness, color and water vapor transmission rate.

Metallic ions distribution in texture and phenolic content contrasted cider apples

Abstract Metallic ions were quantified and mapped at the tissue and the cell scales in two texture and phenolic content contrasted cider apples by atomic absorption spectroscopy, ion chromatography and synchrotron cryo X-ray fluorescence imaging. Metallic ions content and gradient distribution from the cuticle to the inner tissue significantly varied between years of harvest (1–294 % of differences between years). The content of non-esterified uronic acid in the cell wall pectin was also measured (3.1 and 4.9 mol kg−1 of dry weight fruit) and found higher than the total metallic ions in the two varieties (0.22 and 0.27 mol kg−1 of dry weight fruit). Calcium content and cell wall pectin methyl-esterification were not determinants distinguishing firm from soft apples. The results are discussed with regard to the co-location of metallic ions with the phenolic compounds which questions their role in oxidative mechanisms during fruit development and processing, affecting particularly the colour and taste of fruit products.

Development of nanotechnologies for curd dessеrts and fruit and vegetable cryo-additives for their preparation as bas enrichers, structure-forming agents, and colorants

The paper reports the newly devised method and nanotechnology for production of curd desserts for healthy nutrition. They include the mechanical processing of curd grains accompanied by processes of mechanical activation and non-enzymatic catalysis of the casein-calcium-phosphate complex into a nanoscale form, as an innovation. The nanotechnology of cryo-additives made from fruits and vegetables has been devised. We used them as fortifiers with biologically active substances (BAS), natural structure formers and colorants in curd desserts. New curd desserts have the nanoscale form and possess a high content of natural BAS of fruits and vegetables (β-carotene, phenolic compounds, tannins, chlorophylls, L-ascorbic acid and soluble pectin substances). The latter serve as natural fortifiers and structure formers in curd desserts. The above makes it possible to eliminate a need to use food additives and synthetic additives. The low-fat curds were used as a base for production of curd desserts for healthy nutrition. We selected the following raw materials for production of fruit and vegetable cryo-additives: carotene-containing fruits (pumpkin, apricots, and sea buckthorn), citruses (lemons with rind), Jerusalem artichokes, spinach, and apples. We considered homogenization of a product as a technological approach, which leads not only to obtaining of a homogeneous structure of a product, but also to processes of mechanical activation, mechanical destruction and mechanolysis, which is destruction of a protein to its individual components. An increase in the mass fraction of free α-amino acids and simple peptides occurs during the mentioned processes. The study showed that 40...45 % of the bound α-amino acids of protein transform into a free, easily digestible form. The size of α-amino acid molecules is from 0.3 to 1.5 nm. We revealed the mechanism of the process associated with the mechanocracking of protein and its components with mineral substances in the study. The fillers in the form of cryopaste made of fruits and vegetables for curd desserts have been prepared. They are the source of a unique complex of natural biologically active substances, namely, phytocomponents, such as phenolic compounds (1...2.1 %), carotenoids (32.6...45.6 mg per 100 g), L-ascorbic acid (102...260 mg per 100 g), and chlorophylls (800...1,680 mg per 100 g). We showed that fruit and vegetable cryopastes exceed raw materials by 2.5...3.5 times in the content of biologically active substances, due to extraction of hidden forms of BAS from raw materials. In addition, they have a high content of soluble pectic substances due to extraction of hidden inactive forms into a free form from fresh raw materials when preparing paste-like cryofillers. We developed formulations and technology for curd desserts and studied the content of BAS. Curd desserts exceed the known analogues by chemical composition.

Microgel particle formation: Influence of mechanical properties of pectin-based gels on microgel particle size distribution

Microgel particle formation usually requires a dispersing/emulsifiying step of macrogel into pieces, or of direct-gelled droplets. Either liquid or solid-like, yields and fails under given critical conditions. In this work we studied the influence of a gel's mechanical properties on the resulting particle/droplet sizes. As the structure of the polymer influences its mechanical properties, the viscoelastic and mechanical response of pectin gels towards shear, compressive and tensile stress were analysed. Gels were prepared with different pectin types (amidated pectin and citrus pectin) and pectinic acid, at a constant stoichiometric molar ratio R = 2 x [Ca2+]/[COO−] = 1. A dependency of storage modulus G′, Young's modulus E, and critical breakup stresses and strains on the pectin type used for gelation was shown. Values of the storage modulus G′ were influenced by the degree of methyl-esterification (DM), indicating an increase on the cross-linking density of gels. Gels prepared with pectinic acid (DM = 2) showed overall the highest values of G’. Values of the Young's modulus E as well as fracture stresses and strains depended on the type of strain applied to the gel and the pectin type. Concordant with the G′ values, gels become stiffer and brittle with increasing DM, resulting in higher E values, lower fracture strains and higher fracture stresses. In addition, under compressive stress, gels investigated sustained lower stress values before structural failure. The findings of mechanical and rheological analyses were compared with the particle size distribution of microgels produced from the prepared gels at constant process conditions. Gels with high values for G′ and E, and low fracture stresses and strains were shown to be dense cross-linked gels of brittle material characteristics which resulted in smaller particles compared to more elastic gels.

Carbohydrate-Based Fat Mimetics Can Affect the Levels of 3-Monochloropropane-1,2-Diol Esters and Glycidyl Esters in Shortbread Biscuits

Shortbread biscuits have become one of the most desirable snacks in all population groups but due to its high fat content it is searching for new solutions of fat reduction such as the use of carbohydrate-based fat mimetics. However, the thermal processing of food containing lipids in the presence of certain carbohydrates can contribute to the formation of toxic compounds or alter its levels. Therefore, the aim of the study was to evaluate the use of inulin and pectin gels as partial fat replacers (10–40%) in classical shortbread biscuits in a view of the changes of 3-monochloropropane-1,2-diol ester (3-MCPDE) and glycidyl ester (GE) levels after baking, and also after a two-months storage. The experiment showed that the amount of inulin gel higher than 10% promoted the endogenous formation of 3-MCPDE probably due to the higher amount of Maillard products formed in the biscuits, but after two months the levels decreased and were comparable with those transferred from shortening. Pectin did not demonstrate such phenomenon, owing to the presence of bound water in gel. Glycidyl esters were partially decomposed during baking and also during storage, particularly in the samples with the addition of pectin gel, which presumably caused by low stability of GE under acidic conditions resulting from the occurrence of galacturonic acid in pectin.

Utilization of by-products of Hibiscus sabdariffa L. as alternative sources for the extraction of high-quality pectin.

The by-products of Hibiscus sabdariffa L. (HsL), obtained after soaking or decoction of the calyces of Colima and Sudan cultivars, were used for pectin extraction. After soaking, the wastes of both cultivars gave higher yields of pectin than those obtained by decoction. The pectin of the wastes by soaking presented high methoxyl groups, galacturonic acid content, viscosity and gelling capacity. Pectin of this treatment also exhibited bands in the regions of 1750cm-1 and 1630cm-1 that represents the C=O stretching vibrations of methyl ester and the amounts and degree of esterification of the HsL pectin. Interestingly, the pectin retained the typical red color of fresh HsL calyces. The amounts of anthocyanins and ascorbic acid of pectin did not show effects against pathogenic microorganisms. Nonetheless, pectin of the Sudan HsL wastes obtained by soaking, exhibited higher properties than those of the citric pectin, thus, demonstrating its potential for industrial applications.

In vitro study of BSA gel/polyelectrolite complexes core shell microcapsules encapsulating doxorubicin for antitumoral targeted treatment

The aim of this study is to develop core shell microcapsules of bovine serum albumin (BSA) gel with a complex polyelectrolite multilayer shell of natural polysaccharides with opposite charges, pectin (P), chitosan (Chi), and hyaluronic acid (HA) respectively, encapsulating Doxorubicin (Dox) as a carrier for targeted anti-tumoral treatment of hepatic cell carcinoma (HCC). A sacrificial CaCO3 template method was used in order to obtain microcapsules with a BSA gel core and a layer-by-layer (Lbl) deposition technique of polyelectrolite complexes formed between P/Chi in the inner layers and HA/Chi in the outer shell layers. The preformed microcapsules, BSA gel/P/Chi/HA, noted as ms, have been applied for Dox encapsulation (ms-Dox). Dox encapsulation and release in different pH media were studied in order to elucidate the interactions between pH dependently charged species involved in the Dox loading/releasing processes. The structure characterization of ms/ms-Dox was evaluated by FTIR and UV-Vis spectroscopy, X-ray diffraction, thermal analy sis, optical microscopy, confocal laser scanning microscopy, and scanning electron microscopy. The in vitro study for citotoxicity assessment on normal and tumoral cells of both ms and ms-Dox was performed using mesenchymal stem cells (MSCs) and Hep2G HCC cell lines. Results of physical-chemical analyses confirm the successful encapsulation of Dox in ms, and the in vitro biological study recommends ms-Dox as a candidate for future in vivo research as a targeted anti-tumoral treatment modality applications.