Pectin Production Research Articles

Analysis of the Golgi apparatus in Arabidopsis seed coat cells during polarized secretion of pectin-rich mucilage.

Differentiation of the Arabidopsis thaliana seed coat cells includes a secretory phase where large amounts of pectinaceous mucilage are deposited to a specific domain of the cell wall. During this phase, Golgi stacks had cisternae with swollen margins and trans-Golgi networks consisting of interconnected vesicular clusters. The proportion of Golgi stacks producing mucilage was determined by immunogold labeling and transmission electron microscopy using an antimucilage antibody, CCRC-M36. The large percentage of stacks found to contain mucilage supports a model where all Golgi stacks produce mucilage synchronously, rather than having a subset of specialist Golgi producing pectin product. Initiation of mucilage biosynthesis was also correlated with an increase in the number of Golgi stacks per cell. Interestingly, though the morphology of individual Golgi stacks was dependent on the volume of mucilage produced, the number was not, suggesting that proliferation of Golgi stacks is developmentally programmed. Mapping the position of mucilage-producing Golgi stacks within developing seed coat cells and live-cell imaging of cells labeled with a trans-Golgi marker showed that stacks were randomly distributed throughout the cytoplasm rather than clustered at the site of secretion. These data indicate that the destination of cargo has little effect on the location of the Golgi stack within the cell.

Preparation and characterization of amidated pectin based hydrogels for drug delivery system

In the current studies attempts were made to prepare hydrogels by chemical modification of pectin with ethanolamine (EA) in different proportions. Chemically modified pectin products were crosslinked with glutaraldehyde reagent for preparing hydrogels. The hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), organic elemental analysis, X-ray diffraction studies (XRD), swelling studies, biocompatibility and hemocompatibility studies. Mechanical properties of the prepared hydrogels were evaluated by tensile test. The hydrogels were loaded with salicylic acid (used as a model drug) and drug release studies were done in a modified Franz's diffusion cell. FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands. XRD studies indicated increase in crystallinity in the hydrogels as compared to unmodified pectin. The degree of amidation (DA) and molar and mass reaction yields (YM and YN) was calculated based on the results of organic elemental analysis. The hydrogels showed good water holding properties and were found to be compatible with B-16 melanoma cells & human blood.

Mode of De-esterification of Alkaline and Acidic Pectin Methyl Esterases at Different pH Conditions

Highly esterified citrus pectin was de-esterified at pH 4.5 and 8.0 by a fungal pectin methyl esterase (PME) that was shown to have an acidic isoelectric pH (pI) and an acidic pH optimum and by a plant PME that was characterized by an alkaline pI and an alkaline pH optimum. Interchain and intrachain de-esterification patterns were studied by digestion of the pectin products with endo-polygalacturonase and subsequent analysis using size exclusion and anion-exchange chromatography. No effect of pH was observed on the de-esterification mode of either of the two enzymes. Acidic, fungal PME converted pectin according to a multiple-chain mechanism, with a limited degree of multiple attack at the intrachain level, both at pH 4.5 and at pH 8.0. A multiple-attack mechanism, with a high degree of multiple attack, was more appropriate to describe the action mode of alkaline, plant PME, both at pH 4.5 and at pH 8.0.

Production of low methoxyl pectin using immobilized pectinmethylesterase silica from acerola (Malpighia glabra L.)

AbstractThe aim of this work was to develop an efficient reactor for the production of low methoxyl pectin, using pectinmethylesterase (PME, EC 3.1.1.11) from acerola immobilized on silica. The immobilized enzyme was used in up to 50 successive bioconversion runs at 50 °C with an efficiency loss of less than 20%. The fixed‐bed reactor (6.0 × 1.5 cm) was prepared using PME immobilized in glutaraldehyde‐activated silica operated at 50 °C with an optimum flow rate of 10 mL h−1. The bioconversion yield was shown to strongly depend on the nature of the enzymatic preparation. An efficiency of 44% was achieved when concentrated PME was used, compared with only 30% with purified PME, both after an 8‐h run. The process described could provide the basis for the development of a commercial‐scale process. Copyright © 2006 Society of Chemical Industry

Pectin: new insights into an old polymer are starting to gel

Pectin is a high value functional food ingredient widely used as a gelling agent and stabilizer. It is also an abundant, ubiquitous and multifunctional component of the cell walls of all land plants. Food scientists and plant scientists therefore share a common goal to better understand the structure and functionalities of pectic polymers at the molecular level. The basic properties of pectin have been known for nearly 200 years, but recently there has been tremendous progress in our understanding of the very complex fine structure of pectic polymers and pectinolytic enzymes. This has been made possible by synergies between plant and food research and by the application of a range of state-of-the-art techniques including enzymatic fingerprinting, mass spectrometry, NMR, molecular modelling, and monoclonal antibodies. With this increased knowledge comes the prospect of novel applications. Producers are beginning to develop a new generation of sophisticated designer pectins with specific functionalities. Moreover, the ability to manipulate pectin in planta would have a major impact on fruit and vegetable quality and processing, as well as on pectin production.

Utilization of mango peels as a source of pectin and polyphenolics

Two different options for the combined recovery of pectin and phenolic compounds from mango peels, a byproduct of industrial mango processing, were developed. After extraction of dried mango peels with diluted sulfuric acid, the phenolic compounds were adsorbed using a styrene–divinylbenzene copolymerisate resin, and pectin was obtained from the effluent by precipitation with ethanol. Phenolic compounds were recovered from the resin with methanol and the eluate was lyophilized (Process I). Alternatively, the pectin was precipitated by adding the crude extract to ethanol. After removal of the organic solvent, the phenolic compounds were obtained from the aqueous phase of the precipitation bath using the adsorbent resin as described before (Process II). While in total, 129.4 mg/g polyphenols were detected in the lyophilizate obtained from Process I, only 71.0 mg/g dm could be recoverd from Process II. The profiles of the polyphenols were almost identical, revealing that during pectin precipitation preferential adsorption of polyphenolic compounds to the pectin may be excluded. Besides the characterization of the pectins and the phenolic compounds, investigations into the influence of the drying temperature on the polyphenolic content of the peels were carried out, indicating a significant loss of flavonol glycosides depending on heat exposure. On the other hand, some xanthone glycosides were formed during the drying process. Furthermore, antioxidative capacities of the lyophilized eluates were investigated using the DPPH, TEAC and FRAP assays. The antioxidative capacity of the extracts exceeded that of mangiferin and quercetin 3- O-glucoside, respectively, thus demonstrating mango peels to be a suitable source of health-beneficial compounds. The lyophilizates obtained from Process I showed higher antioxidative capacities in all three assays. These findings indicate a correlation between the amount of phenolic compounds and the antioxidative capacity. Industrial relevance Byproducts of mango processing amount to 35–60% of the total fruit weight. Their complete exploitation for further product recovery is a promising measure from both an environmental and economic point of view. In our previous study mango peels were found to be a rich source of pectin, with a high degree of esterification and phenolic compounds, like flavonol O- and xanthone C-glycosides. Therefore, two alternative processes for the combined recovery of pectin and polyphenols, which can easily be integrated in an existing pectin production process, were developed in the present study.

Effect of calcium, phosphate and nitrogen on cell growth and biosynthesis of cell wall polysaccharides by Silene vulgaris cell culture

Medium nutrients such as calcium, phosphorus, nitrogen and nitrate to ammonium ratio have significant influence on the growth, biosynthetic and biochemical characteristics of polysaccharides produced by Silene vulgaris (M.) G. cell culture. Cell growth and production of polysaccharides was limited by an absence of any of these components in the medium. Optimal growth of the callus and production of arabinogalactan were achieved at 1.5–4.5 μM calcium while the optimal production of pectin named silenan was observed at 3.0–4.5 μM. The phosphate contents in the medium in the range of 0.63–3.75 μM were favorable for callus growth. Production of silenan was maximal at 1.25–3.75 μM phosphate. Optimal growth of the callus was achieved at 30–90 μM nitrogen. Maximal production of silenan was observed at 60 μM nitrogen while the optimal production of arabinogalactan was at 90 μM nitrogen (at ratio of NH 4 +:NO 3 − as 1:2). A presence both of nitrate and ammonium is needed for the silenan biosynthesis (the NH 4 +:NO 3 − ratio as 1:1 and 1:2). Yields and volumetric production of arabinogalactan were maximal at deletion of ammonium from the nutrient medium (ratio 0:1). Absence of calcium or nitrogen in the medium leads to a decrease of the galacturonic acid residues in silenan. The galactose residues contents in arabinogalactan were decreased in the absence of nitrogen and calcium in the medium.

Characteristics of beef burger as influenced by various types of lemon albedo

Citrus fruits constitute an underused source of fibre and antioxidants, particularly albedo, and the potential for its use is explored. Lemon albedo was prepared from pith following four different methods either cooking or/and drying and mincing. These ingredients were added at 0%, 2.5%, 5% and 7.5% levels to a beef burger mix and the burgers were evaluated for quality attributes including: compositional analysis, cooking characteristics, fat oxidation, pH, physical tests (included colour and texture profile analysis) and a range of sensory attributes using a ranking test. The type of albedo slightly influenced the lipid oxidation and pH of samples, while the cooking properties were significantly improved by some of the added treatment materials with average increments of 5.5–11% on treatment meat patties when compared with control samples. Instrumental colour testing showed some differences on lightness, yellowness and redness, while hardness, gumminess, springiness and chewiness were in general, consistently higher as albedo concentration increased. The dry ingredient also had a stronger effect. The sensory evaluation highlighted significant differences on redness and hardness. Samples were also ranked distinctly in relation to their overall acceptance where only treatments with raw albedo compared poorly to the rest of samples, which indicates potential to develop this material as a food ingredient. Industrial relevance Citrus fruits are mainly used for juice, oil and pectin production and are underutilized sources for dietary fibre and antioxidants. This work examined the effects of lemon albedo on chemical, physicochemical and sensory properties of beef burgers especially to improve cooking properties. Besides reduced cooking losses citrus fibre seems to have potential as alternative to conventional fillers in meat product.

Pectinolytic Systems of Two Aerobic Sporogenous Bacterial Strains with High Activity on Pectin

Strains Paenibacillus sp. BP-23 and Bacillus sp. BP-7, previously isolated from soil from a rice field, secreted high levels of pectinase activity in media supplemented with pectin. Production of pectinases in strain Paenibacillus sp. BP-23 showed catabolite repression, while in Bacillus sp. BP-7 production of pectin degrading enzymes was not negatively affected by glucose. The two strains showed lyase activities as the predominant pectinases, while hydrolase activity was very low. Analysis of Paenibacillus sp. BP-23 in SDS-polyacrylamide gels and zymograms showed five pectinase activity bands. The strict requirement of Ca(2+) for lyase activity of the strain indicates that correspond to pectate lyases. For Bacillus sp. BP-7, zymograms showed four bands of different size. The strain showed a Ca(2+) requirement for lyase activity on pectate but not on pectin, indicating that the pectinolytic system of Bacillus sp. BP-7 is comprised of pectate lyases and pectin lyases. The results show differences in pectin degrading systems between the two aerobic sporogenous bacterial strains studied.

Use of NIR spectroscopy and chemometrics for on-line process monitoring of ammonia in Low Methoxylated Amidated pectin production

The development of an on-line process monitoring and control system for the automatic dosing of ammonia for production of Low Methoxylated Amidated (LMA) pectin is described. The system is based on on-line optical fibre Near Infra-Red (NIR) transmittance spectroscopy of the amidation liquid, consisting of ammonia, isopropylic alcohol, water and minor impurities. The focus in this paper is on the chemometric calibration development and validation, and the improvement on the ammonia dosing for the production. Feasibility studies revealed that the calibration for ammonia, based on NIR transmittance spectra (spectral region from 5300 to 11 000 cm −1) is highly temperature dependent in the range −9–20 °C, but careful choice of spectral pre-processing and wavelength selection could eliminate the temperature dependency. Using the first derivative of the NIR spectra and the selection of the spectral region 5423–6658 cm −1, the average Partial Least Squares regression prediction error was reduced to 1.75% of the full range of the initial calibration, as determined from an independently validated data set one full year after initial implementation in the factory.

Gelatin-immobilized pectinmethylesterase for production of low methoxyl pectin

The optimum conditions for the production of low methoxyl pectin using pectinmethylesterase (PME) from acerola ( Malpighia glabra L.), immobilized in gelatin, have been established by factorial design and response surface methodology. In the case of the free enzyme, the optimum conditions for activity, within ranges adequate for food processing, are low NaCl concentrations (0.10 M), relatively high temperatures (55 °C) and slightly basic pH values (pH=9). The temperature and pH seem to have strong influence on the observed activity. In the immobilized enzyme, optimum NaCl concentration was 0.15 M, while the optimum pH remained at 9.0.

Optimization of narirutin extraction during washing step of the pectin production from citrus peels

Citrus peels can be a valuable source of pectin and narirutin. Narirutin can be extracted during the washing step of citrus peels in the pectin production process. In this study narirutin extraction conditions were optimized to maximize the narirutin extraction yield while minimized pectin loss. Washing temperature, time, and HCl concentration of the washing solution were chosen as independent variables of the central composite design. The results showed a good fit with the second-order polynomial equation, which was statistically acceptable at P<0.05 level. Pectin loss was directly correlated with the increases in temperature, time, and HCl concentration during washing procedure. Consequently, the higher the temperature and longer the time, the yield of narirutin extracted was greater, although higher HCl concentration had a negative effect on narirutin extraction yield. The present study indicated that the combination of washing temperature (62 °C), time (30 min), and the absence of HCl in the washing solution was found to be optimum conditions, yielding 0.6% of narirutin with a pectin loss of only 1.5% based on the dry citrus peels. The characterization of narirutin extracted from citrus peels was performed using HPLC and NMR.

Concentration and purification of soluble pectin from mandarin peels using crossflow microfiltration system

A crossflow microfiltration process was developed to concentrate and purify soluble pectin extracted from the mature citrus peel. The extracted pectin solution was concentrated with the crossflow microfiltration using a 0.2 μm regenerated cellulose membrane. As a result of crossflow microfiltration, the galacturonic acid content of pectin increased from 68.0 to 72.2% while the recovery yield of pectin decreased from 10.5 to 9.9%. In addition, the volume of ethanol used for the recovery of pectin could be reduced to 25%. To purify pectin further, the concentrated pectin extracts was washed using the fed-batch type diafiltration system. By diafiltration, the galacturonic acid content of pectin increased from 72.2 to 75.6%. The yield of pectin, however, decreased from 9.9 to 9.4% at six volumes of diafiltration. The diafiltration process was also effective to remove flavonoids, polyphenols and carotenoids, which were impurities in pectin products. Therefore, the crossflow microfiltration system could be efficiently used for concentration and purification of pectin.

Isolation of oligomeric proanthocyanidins from flavonoid-producing cell cultures

The extraction, fractionation, and chromatographic separation of a series of proanthocyanidin monomers and oligomers were facilitated using a flavonoid-rich cell culture of Vaccinium pahalae Skottsberg as the donor tissue. The cell cultures, after exposure to light, readily accumulated anthocyanin pigments and other flavonoids in relatively large amounts, with minimal concurrent production of pectins, enzymes, and complex sugars produced in field-grown Vaccinium berries. The absence of these interfering compounds greatly simplified the isolation and purification of proanthocyanidins and other phenolic compounds from cell cultures, primarily using vacuum chromatography. Subsequently, the structures and molecular weights of several individual compounds and the general composition of unresolved fractions were established with 1H- and 13C-NMR and MS. The initial extract of V. pahalae cell cultures was readily fractionated on silica gel to yield a series of fractions containing proanthocyanidin B-2, a series of increasingly polar proanthocyanidin oligomers ranging from dimers to heptamers largely based on (−)-epicatechin structures (some with A-type linkages), a mixture of E- and Z-p-coumaric acid, the corresponding 4-O-glucoside, and other compounds containing E- and Z-p-coumaric acid moieties. Cell culture extracts demonstrated broad antioxidant capacity and significant ability to inhibit tumor promotion in vitro, as indicated in an ornithine decarboxylase assay.

Effect of dietary high-and low-methylated citrus pectin on the activity of the ileal microflora and morphology of the small intestinal wall of broiler chicks

1. A study was conducted with broiler chicks to evaluate the effects of dietary high-methylated citrus pectin (HMC) or low-methylated citrus pectin (LMC) on the performance, nutrient digestibility , morphology of the small intestinal wall and ileal microbial activity. 2. Both pectin products were tested at a dietary content of 30 g/kg using a diet based on maize and soya flour. 3. Inclusion of HMC in the diet depressed weight gain and food utilization significantly. With a dietary addition of LMC there were only small decreases in weight gain and food utilisation. 4. Digestibility of dry matter, organic matter, crude fat, starch and amino acids, nitrogen retention and metabolisable energy value were reduced significantly when HMC was added to the diet. The addition of LMC to the diet reduced fat and ash digestibility and metabolisable energy value significantly. 5. Inclusion of LMC in the diet increased ileal viscosity marginally, whilst HMC had such an effect that the supernatant could not be extracted. Microbial activity in the ileum, particularly that of Enterococci , Bacteroidaceae , Clostridia and E. coli , was increased significantly with dietary addition of HMC. Inclusion of LMC in the diet did not greatly affect microbial activity as only the number of Clostridia was increased. 6. The addition of HMC to the diet markedly affected the morphology of the intestinal wall and significantly increased the number of goblet cells per 100 villus cells and the sucrase isomaltase activity was increased significantly . However, the morphology of the intestinal wall was hardly affected by LMC, whereas the number of goblet cells per 100 villi cells was significantly increased. 7. Results of the present study indicate that the inclusion of water-soluble pectins in diets of chicks changes ileal microbial activity and the morphology of the small intestinal wall. The magnitude of these changes depends on the degree of methylation of the pectins.

Extrusion of Apple Pomace Facilitates Pectin Extraction

ABSTRACTTwin‐screw extruder was employed to disintegrate apple pomace (AP) to facilitate production of apple pectins by hot water extraction. AP was extruded under different conditions of screw speed, 250‐350 rpm; feed rate, 30‐40 kg/h; moisture, 20‐30%. The yield of water soluble polysaccharides (WSP) increased with increasing specific mechanical energy (SME), but intrinsic viscosity decreased with increasing SME. Considering both the WSP yield (g/dL) and intrinsic viscosity (dL/g), a dimensionless term, product yield ∞ intrinsic viscosity (Y[]), was an objective function for optimizing conditions for the solubilization of AP polysaccharides. Y[] of pectins in extruded WSP ranged 0.59‐1.34, while acid extracted WSP had Y[] of 1.12. Extruded WSP with Y[] comparable to acid extraction was obtained in the SME ranges of 110‐170 kWh/h.

EFFECTIVENESS OF SELECTED ADJUNCTS ON PROCESSING AND SENSORY CHARACTERISTICS OF EXTRA LEAN FRANKFURTERS

ABSTRACT The effects of maximum levels of selected additives in extra lean frankfurters (&lt;3% fat) were studied. Seven treatments, with four replications each, were evaluated at three time periods (0, 30 and 60 days) in a randomized complete block design. The treatments consisted of: control; kappa‐carrageenan; hydroxypropyl methylcellulose (HPMC); high methoxy pectin (pectin); an acid modified food starch; sodium lactate; and acid enzyme deheated mustard. All treatment frankfurters had higher (P&lt;0.05) yields than the controls. The pectin product had an unacceptable extremely soft, smooth pasty texture. Pectin and HPMC products had the lowest (P&lt;0.05) purge at 60 days. In general, the addition of some appropriate additive or additives to low‐fat sausage products appears to be appropriate to increase processing yields, reduce cost and help bind free water so long as the additive or additives do not adversely affect other properties of the product.

Nutritional Implications of Pectins in Chicks in Relation to Esterification and Origin of Pectins

An experiment was conducted to examine the effect of feeding high-methylated (HM) and low-methylated (LM) pectin on performance and physiological characteristics in broiler chicks. Two levels each (1.5 and 3%) of HM citrus pectin (HMC), LM citrus pectin (LMC), or HM sugar beet pectin (HMS) were added to a semi-purified basal diet. The experiment was conducted in battery brooders, and chicks received the diets as pellets from 6 to 27 d of age.The inclusion of LMC or HMS in the diet had little or no effect on the performance of chicks; however, when HMC was added to the diet growth and feed utilization were reduced significantly (P < 0.05). Water intake and water:feed ratio were increased (P < 0.05) after inclusion of all three pectin products in the diet. The effect on water consumption was more pronounced in the HMC-containing diets than in the LMC or HMS diets, and was dose-dependent. In vitro viscosity was increased significantly by incorporating HMC or LMC into the diet, whereas HMS had no effect on this parameter. Water-holding capacity of the diets and the excreta were increased significantly by including one (P < 0.05) of the three pectin products in the diet. The concentration of some of volatile fatty acids (VFA) in the cecal chyme was markedly decreased (P < 0.05) by feeding HMC, whereas LMC had no effect (P > 0.05) on the concentration of VFA. In contrast, inclusion of HMS in the diet significantly increased the concentration of VFA in the cecal content (P < 0.05) dose-dependently. Based on the results of the present study, it can be concluded that the effect of dietary pectin on chick performance is dependent on the degree of carboxyl groups that is esterified, the origin of the pectin product, and the amount added to the diet.

Ericoid mycorrhizal fungi: cellular and molecular bases of their interactions with the host plant

A number of soil-borne fungi are able to form typical ericoid mycorrhizae with plants belonging to Ericales. Together with Hymenoscyphus ericae, the first isolate from roots of ericaceous plants, other fungal species belonging to the genus Oidiodendron and many sterile mycelia have been recognized as mycorrhizal by several authors. A high genetic diversity was even found when a population of ericoid mycorrhizal fungi isolated from a single plant of Calluna vulgaris was analysed with morphological and molecular techniques. Ericoid fungi have a relevant saprotrophic potential, as they can degrade several organic polymers present in the soil matrices. Different cell wall degrading enzymes, which are part of this arsenal and are produced in vitro by several ericoid fungi, have been investigated biochemically. Immunocytochemical studies on the production of pectin degrading enzymes during the infection process of host and non-host plants suggest that regulation mechanisms for the production of cell wall degrading enzymes in vivo may be a crucial step for the establishment of successful mycorrhiza with host plants. Key words: ericoid mycorrhizae, cell wall degrading enzymes, polygalacturonase, DNA-RAPD techniques.

Production of low methoxyl pectin using immobilized pectinesterase bioreactors

Soluble pectinesterase (EC 3.1.1.11) from germinating seeds of Vigna sinensis has been immobilized on egg shell as well as in gelatin matrices. The egg shell-immobilized enzyme showed higher specific activity and purification fold than that immobilized in gelatin. There is a shift in the optimum pH without distortion of the profile on immobilization of the enzyme on egg shell and in gelatin as well. The immobilized enzymes showed higher optimum temperature than the soluble enzyme and also a marked increase in thermal stability. Pectinesterase immobilized on egg shell without glutaraldehyde was reusable 32 times at 30°C, compared to 24 times for enzyme immobilized on egg shell with glutaraldehyde treatment and 18 times for that immobilized in gelatin. Three types of reactors: fixed bed, fluidized bed and stirred tank have been prepared using hen egg shell-bound pectinesterase. Fluidized bed reactor (2×10 cm), operated at an optimum flow rate of 5 ml/h and temperature 35°C, showed better results for production of low methoxyl pectin.