Pectinase Treatment Research Articles

Treating bast fibres with pectinase improves mechanical characteristics of reinforced thermoplastic composites

The effect of pectinase treatment of hemp ( Cannabis sativa L.) fibres on mechanical properties of fibre reinforced polypropylene was investigated. Incubating technical fibres with pectinase (SIHA-Panzym ® DF) reduced their cross-sectional area (8.72 × 10 −3 vs. 3.67 × 10 −3 mm 2, control vs. pectinase incubation) and decreased tensile strength (455.4 vs. 171.2 MPa). Polypropylene (PP) was reinforced with these fibres using conventional extrusion and injection moulding techniques. Maleic anhydride grafted PP was applied as compatibilizer. The cross-sectional area of fibres in the composite decreased from 2.58 × 10 −4 to 1.21 × 10 −4 mm 2 for control vs. pectinase. Tensile strength (43.7 vs. 47.6 MPa for control vs. pectinase incubation), flexural strength (49.9 vs. 56.6 MPa) and moduli of elasticity (tensile, 2.62 vs. 3.25 GPa and flexural, 2.28 vs. 2.87 GPa, respectively) all increased when using fibres incubated in pectinase. Qualitatively and quantitatively similar effects, albeit on a decreased level, were obtained when reinforcing PP in absence of the compatibilizer. The data indicate the refining of technical fibres in response to pectinase treatment. This effect was accomplished by (1) enzymatic decomposition of the middle lamellae, (2) mechanical stress exerted by compounding and (3) compression of cell lumina. The separation of technical fibres into smaller bundles and single fibre cells, in turn, resulted in improved tensile and flexural characteristics of thermoplastic composites.

Wax removal for accelerated cotton scouring with alkaline pectinase

A rational approach has been applied to design a new environmentally acceptable and industrially viable enzymatic scouring process. Owing to the substrate specificity, the selection of enzymes depends on the structure and composition of the substrate, i.e. cotton fibre. The structure and composition of the outer layers of cotton fibre has been established on the basis of thorough literature study, which identifies wax and pectin removal to be the key steps for successful scouring process. Three main issues are discussed here, i.e. benchmarking of the existing alkaline scouring process, an evaluation of several selected acidic and alkaline pectinases for scouring, and the effect of wax removal treatment on pectinase performance. It has been found that the pectinolytic capability of alkaline pectinases on cotton pectin is nearly 75% higher than that of acidic pectinases. It is concluded that an efficient wax removal prior to pectinase treatment indeed results in improved performance in terms of hydrophilicity and pectin removal. To evaluate the hydrophilicity, the structural contact angle (theta) was measured using an auto-porosimeter.

Degradation kinetics of pectins by an alkaline pectinase in bioscouring of cotton fabrics

Alkaline pectinases have been proven to be effective as bioscouring agents of cotton fabrics. In order to monitor the scouring degree of cotton fabrics quantificationally, a kinetic study of the degradation of pectins in cotton by an alkaline pectinase ‘Bioprep 3000L’ was performed and the influences of initial pectinase concentration and treatment time on bioscouring were evaluated quantitatively. The results showed that although the degradation products increased as pectinase concentration grew higher at same incubation time, the growth multiples of the maximum degradation rate which was used as the starting degradation rate were less than those of initial enzyme concentration. The degradation kinetics of pectins in cotton fibers with a pectinase could be described by modified Ghose–Walseth kinetic empirical equations which had been previously applied to the degradation reaction of cellulose.

ALTERNATIVE PRETREATMENT METHODS TO ENZYMATIC TREATMENT FOR CLARIFICATION OF MOSAMBI JUICE USING ULTRAFILTRATION

ABSTRACT A series of pretreatment methods to mosambi juice were undertaken and results were compared to pectinase treatment for clarification of the treated juice using ultrafiltration. The pretreatment methods attempted were centrifugation, centrifugation followed by addition of gelatin, centrifugation followed by addition of bentonite, centrifugation followed by fining using both bentonite and gelatin and enzymatic treatment, using pectinase as the enzyme. A systematic study was undertaken to select the operating centrifugation speed and time. The permeate flux and quality of the permeate were comparable to the enzyme‐treated juice.

An ultracentrifugation-based approach to the detection of hepatitis A virus in soft fruits

A method was developed for detection of hepatitis A virus (HAV) in soft fruits (raspberries and strawberries). After washing the sample in 1 M sodium bicarbonate with added soya protein, fruits were removed by slow speed centrifugation, then particulate material and residual pectin were removed from the supernatant by flocculation and pectinase treatment during another slow speed centrifugation. Virus particles were then sedimented by ultracentrifugation. RNA was extracted from the virus particles, and nested RTPCR was performed on the nucleic acid extract. Nested RTPCR comprised an RTPCR, followed by PCR to amplify sequences within the amplicon. Internal amplification controls (IACs) were constructed for both the RTPCR and the PCR. The sensitivity of the nested RTPCR was approximately 10 RTPCRU. The overall method was shown to be able to detect 10 4 RTPCRU HAV in 90 g fresh strawberries, and 10 3 RTPCRU HAV in 60 g fresh raspberries. It is estimated that the lowest possible limit of detection of the method should be between 40 and 400 RTPCRU HAV per fruit sample. The method can be performed within one day, in suitably equipped microbiological laboratories, and is suitable for routine screening of food samples, and for analysis of suspected samples, e.g. during outbreak investigations.

Phenolic Extraction from Apple Peel by Cellulases from Thermobifida fusca

With the optimization of the pretreatment conditions for the crude Thermobifida fusca cellulase activity and phenolic release from apple peel, we focused on the activity of individual purified cellulase related to the antioxidant activity. The overall phenolic release was significantly increased in a synergistic manner with combined pretreatment, not with individual pretreatment such as boiling, acid, and pectinase treatment. Approximately 60 mg of reducing sugar equivalent were produced per g of apple peel by treatment with T. fusca crude extract, and up to 3 times more reducing sugars were released when the apple peel was boiled and then treated with acid and pectinase. There was good correlation between the release of phenolics and reducing sugar by cellulase treatment and also between the amount of total phenolics and antioxidant capacity by each enzyme treatment (r2> 0.95). Among the tested enzymes purified from T. fusca cell extract, cellulase activity on apple peel was the highest with cellulase 6A (Cel 6A; 43% digestion), and the highest antioxidant capacity was obtained by incubation with Cel 6B (16 mg vitamin C equiv/g). Synergism in the activity was found from the combined treatment with Cel 6A and 6B in both cellulase activity and antioxidant capacity after 20 h of incubation. Cel 9A (progressive endocellulase) exhibited greater cellulase activity and antioxidant capacity than Cel 9A cd which lacks in cellulose-binding module, indicating that the cellulose-binding domain might play important roles in cellulolysis of apple peel. This study could provide some insights into the action mechanism of various cellulases on the digestion of cellulose-containing byproducts and expand the opportunity for cellulase utilization in the extraction of functional ingredients from the plant-derived byproducts.

Implementation of batchwise bioscouring of cotton knits

The examination of critical factors determining the performance of bioscouring showed that a short treatment of the fabric at greater than 80°C after pectinase treatment at 60°C was essential for removal of waxes from the fabric as demonstrated by diminished intensities of methylene peaks in FT-IR measurements. Batch-wise bioscouring of cotton knits was carried out several times with post-treatment at 80°C using a rapid dyeing machine. The dye-ability of bioscoured knits was as good as the company's alkaline scoured ones with slightly higher K/S values. Water pollution caused by effluents of bioscouring and alkaline processes were estimated, as well as that due to the input of chemicals and enzymes. Higher BOD:CODCr ratios for enzymes indicated their biodegradable character. After calculation of energy consumption using a simulation program, an economic evaluation of the two processes was done on the basis of one ton production by considering the costs of chemicals and enzyme, water usage, energy consumption and waste water treatment charge.

Effects of different enzymatic pre-press maceration treatments on the release of phenols into blackcurrant juice

The effects of different pectinolytic enzyme treatments on the release of phenolic compounds from blackcurrant berry mash into juice in experimental blackcurrant juice production were examined. The influence of enzyme dose (0–0.1% by weight), degree of berry crushing, maceration time, and temperature on the total phenol concentration, the juice yield, and on polysaccharide degradation were evaluated for four commercial, fungal enzyme preparations in statistically designed experimental templates. In optimal experimental conditions, treatments with Macer8 [FJ] and Pectinex Ultra SP-L released ~6500 and 6650 mg gallic acid equivalents/L of total phenols, respectively. These levels correspond to increases of 14–15% compared to the juice extracted without enzymes, and were significantly higher than those achieved with Rapidase BE Super and Grindamyl pectinase treatments. Increased enzyme dosage gave larger juice yields and higher phenol concentrations. There was a positive, linear correlation between degradation of the substrate polysaccharides and the amount of phenols released. The juice samples inhibited the oxidation of human low-density lipoproteins in vitro in a dose-dependent matter. The non-enzyme-treated sample exhibited higher antioxidant activity than the enzyme-treated juices at equimolar test levels of phenols, presumably because of differences in their phenolic profiles.

Emulsifying properties of soybean soluble polysaccharide

Soybean soluble polysaccharide (SSPS) is an ingredient extracted from the by-product of the isolation of soybean protein. The objective of this work was not only to study the emulsifying properties of SSPS, but also to determine if different extraction conditions would affect the behavior of the polysaccharide when adsorbed at oil/water interfaces. For this reason, three types of soy polysaccharide, SSPS-L, SSPS-H, and SSPS-M were investigated. Emulsions prepared at pH 3.5–5.0, containing 20% soybean oil and concentrations of SSPS above 4% were stable to creaming for 30 days, for all the SSPS tested. In spite of the presence of galacturonic acid in SSPS, the emulsions were not affected by changes in pH or by addition of CaCl 2 (5–25 mM) or NaCl (5–25 mM). Among the three SSPS tested, SSPS-L extracted at 120 °C and pH 3 for 2 h showed the best emulsifying properties forming stable emulsions at a concentration of 4% and up to 50% oil. Differences in the thickness of the adsorbed layer were found depending on the type of SSPS. The thickness of SSPS calculated after hemicellulase or pectinase treatment was estimated to be about 17 nm (SSPS-L), 21–24 nm (SSPS-H), and 30–36 nm (SSPS-M), respectively. The enzymatic degradation of SSPS resulted in oil droplet aggregation, indicating that oil droplet stabilization occurred mainly via steric repulsion.

Pectinase처리가 감과실 알콜발효에 미치는 영향

감과실의 효율적 활용을 위하여 알콜발효과정에서 pectinase처리에 따른 성분 변화를 조사하였다. pH 및 총산의 변화는 모든 구간에서 크게 나타나지 않았으며 pectinase 처리에 따른 영향은 없었다. 환원당 함량의 변화는 실험구간 모두 발효시간 12시간 이후 급격히 감소하여 60시간부터는 변화가 없었으며 72시간에서는 pectinase 처리 구간이 약간 높게 나타났다. 알콜 함량의 변화는 무처리구보다 pectinase 처리구들이 높게 나타나는 경향이었으나 농도에 따른 차이는 크게 나타나지 않았다. 알콜발효수율은 200, 500 ppm 처리구가 96%로 가장 높았으며 다음은 300, 400 ppm 및 무처리구 순서로 높게 나타났다. 알콜발효과정에서 주요 알콜성분은 acetaldehyde, methanol, ethanol, n-propylalcohol, iso-butylalcohol 및 isoamylalcohol 5종이 분석되었다. Acetaldehyde 및 methanol 함량은 무처리구가 가장 낮았으며 methanol의 함량은 200 ppm처리구가 가장 높았으나 pectinase 처리 및 농도에 따른 차이는 크게 나타나지 않았다. 이상의 결과 감과실 알콜발효과정에서 pectinase 처리는 알콜수율 증가 등에는 효과적이었으나 methanol 함량은 증가시키는 것으로 나타났다. 감과실의 효율적 활용을 위하여 알콜발효과정에서 pectinase처리에 따른 성분 변화를 조사하였다. pH 및 총산의 변화는 모든 구간에서 크게 나타나지 않았으며 pectinase 처리에 따른 영향은 없었다. 환원당 함량의 변화는 실험구간 모두 발효시간 12시간 이후 급격히 감소하여 60시간부터는 변화가 없었으며 72시간에서는 pectinase 처리 구간이 약간 높게 나타났다. 알콜 함량의 변화는 무처리구보다 pectinase 처리구들이 높게 나타나는 경향이었으나 농도에 따른 차이는 크게 나타나지 않았다. 알콜발효수율은 200, 500 ppm 처리구가 96%로 가장 높았으며 다음은 300, 400 ppm 및 무처리구 순서로 높게 나타났다. 알콜발효과정에서 주요 알콜성분은 acetaldehyde, methanol, ethanol, n-propylalcohol, iso-butylalcohol 및 isoamylalcohol 5종이 분석되었다. Acetaldehyde 및 methanol 함량은 무처리구가 가장 낮았으며 methanol의 함량은 200 ppm처리구가 가장 높았으나 pectinase 처리 및 농도에 따른 차이는 크게 나타나지 않았다. 이상의 결과 감과실 알콜발효과정에서 pectinase 처리는 알콜수율 증가 등에는 효과적이었으나 methanol 함량은 증가시키는 것으로 나타났다.

Effect of macerate enzymes on the yield, quality, volatile compounds and rheological property of prickly pear juice.

Pectinase and cellulase enzymes were used to investigate efficacy for improving juice yield, stability and quality from prickly pear fruit. Pectinase improved the yield, stable color, color-assayed as release of anthocyanins or carotinoids and clarity of the juice. A significant increase in the effectiveness of pectinase was observed as the concentration was increased from 0.05 to 0.50% v/w. However, at concentration > 0.25% v/w they tended to impart a bitter flavor in the juice. Among three concentrations of pectinase and cellulase, pectinase at 0.50% v/w produced higher yield, a sediment-free clear juice and high-quality juice. The results indicated that depectinated clarified prickly pear juice behaves as a Newtonian fluid. It was found that the activation energy (Ea) for viscous flow was in the range of 5.02 x 10(3)-20.06 x 10(3) kJ/mol depending on the concentrations of pectinase and cellulase enzyme treatment of prickly pear juice, in contrast to 22.15 x 10(3) kJ/mol in untreated juice. Volatile compound concentrations of twelve compounds were not affected by pectinase and cellulase treatment. Overall the quality of prickly pear juice was better in pectinase-treated juice compared with untreated and cellulase-treated juice.

Reduction of Patulin during Apple Juice Clarification

Patulin is a mycotoxin produced by a number of molds involved in fruit spoilage. This compound is carcinogenic and teratogenic. Various methods are currently used to reduce the levels of patulin in apple juice, namely, charcoal treatment, chemical preservation (sulfur dioxide), gamma irradiation, fermentation, and trimming of fungus-infected apples. Many of these processes are expensive and time-consuming. Therefore, there is a need to find a convenient and economical process to control patulin levels. This study was undertaken to evaluate the effectiveness of several clarification processes for the reduction of patulin. Clarification was carried out on a laboratory scale. Apple pulp was spiked with patulin, pressed, and clarified using four different processes, namely, fining with bentonite, enzyme (pectinase)treatment, paper filtration, and centrifugation. Patulin was recovered from the clarified juice by liquid-liquid extraction, and solid-phase chromatography was used for sample cleanup prior to analysis by high-performance liquid chromatography (HPLC). The minimum detectable limit using HPLC was 20 μg/liter. Pressing followed by centrifugation resulted in an average toxin reduction of 89%. Total toxin reduction using filtration, enzyme treatment, and fining were 70, 73, and 77%, respectively. Patulin reduction was due to the binding of the toxin to solid substrates that was verified by analyzing the clarified juice as well as the filter cake, pellet, and sediment. The combined concentrations correlated to the spiked concentration. These results reveal that clarification was successful in the reduction of patulin levels in apple juice. However, clarification resulted in high levels of patulin in the pressed pulp after filtration and centrifugation, and this could be harmful if they are used as animal feeds.

Structural elucidation of a new arabinogalactan from the leaves of Nerium indicum

A polysaccharide fraction, NIB-2, was obtained from the 3% aqueous sodium carbonate extract of Nerium indicum leaves using anion-exchange chromatography and gel-permeation chromatography. It was found to be composed of rhamnose, arabinose, galactose, in the ratios of 1.0:10.4:4.4, along with 4% of galacturonic acid. The results of methylation analysis, periodate oxidation, partial acid hydrolysis, pectinase treatment, and 13C and 1H NMR spectroscopy indicate that it is mainly an arabinogalactan having a backbone of 1,6-linked β-Gal p, with branches at O-3, consisting of terminal, 1,5-, and 1,3,5-linked arabinofuranosyl residues, and a small proportion of galactosyl residues at the termini. Rhamnose and galacturonic acid arose from a contaminating rhamnogalacturonan.

Polarization confocal microscopy and congo red fluorescence: a simple and rapid method to determine the mean cellulose fibril orientation in plants.

The mean or net preferential orientation of cellulose fibrils in plant cell walls is detected with polarization confocal laser scanning microscopy using the fluorescence dichroism of Congo Red. Single cells, arrays of cells in a tissue, or the epidermis of whole organs can be assayed in vivo. Aerial parts require an extra pectinase treatment because of the cuticle, which is impermeable to aqueous solutions. Peeling off the epidermis can be an elegant alternative, especially for leaves. With this method the net preferential fibril orientation can be related to the symmetry axis of the cell in quantitative terms. Data issuing from this approach are useful in current research on plant biomechanics.

Prevention of ice propagation by permeability barriers in bud axes of Vitis vinifera

A physical barrier exists in Vitis vinifera L. (wine-quality grapevines) between the canes that freeze at subzero temperatures and the buds that supercool, thereby avoiding ice formation in these delicate organs. Our objective was to characterize the ice nucleation barrier by observing grape buds at different stages of acclimation, by treating them with pectinase, and by comparing them to buds of the more hardy Vitis riparia L. and to non-supercooling buds of Populus nigra L. "Italica." Differential thermal analysis (DTA) indicated that as V. vinifera andV. riparia acclimated in the autumn, the ice nucleation point of the buds declined, then increased as the grapevines de-acclimated in the spring. Laser scanning confocal microscopy was used to detect the penetration of fluorescent rhodamine green dyes from the cane into the bud as a measure of apoplastic permeability. These pore size exclusion tests indicated that the bud axes were impermeable to a 3000 MW dextran-conjugated dye when the ice nucleation temperature was below -20°C, but permeable above -20°C. This lower porosity presumably restricts the penetration of ice into the bud from the cane. In contrast to the two Vitis species, the permeability of Populus buds did not limit ice propagation, and the water in buds froze between -5 and -10°C according to DTA. Pectinase and phosphate treatments of grape buds to remove pectin increased apoplastic permeability, increased the ice nucleation temperature, and prevented supercooling according to DTA. Light microscopy indicated that suberin coated the scales of the grape buds, probably preventing ice nucleation from the environment, but was not present in the bud axis region. We concluded that a permeability barrier, possibly containing pectin, in the axis of grape buds limits the propagation of ice into the buds and enables supercooling to occur.Key words: supercooling, freezing, acclimation, winter hardiness, pectin, confocal microscopy.

Sulphite binding in ciders

Summary The extent of sulphite binding was measured in commercial ciders, and experimentally observed binding curves were compared with theoretically derived curves based on assessment of the levels of individual sulphite binding compounds determined in the ciders. Subsequently, experimental ciders were fermented under various controlled conditions using nine different strains of cider yeasts. The results indicated considerable differences both in the levels of sulphite binding compounds produced, and in the ability of different yeast strains to produce SO2 in the cider. Juice concentration and the presence of cloud in juice had little or no effect on sulphite binding. Other factors which affected sulphite binding included the type and condition of juice (especially the effect of pectinase treatment) and, in some instances, the use of added yeast nutrients. Significant sulphite binding was also attributable to unaccountable components, probably derived from poor quality fruit, which were present in the apple juice prior to fermentation.

QUALITY CHANGES DURING STORAGE IN KOREAN CLEAR PEAR JUICES CONCENTRATED BY THREE METHODS

ABSTRACTPears of Shingo variety were coarsely ground, and subjected to heat treatment by HTST (high temperature short time) and pectinase treatment to produce a cloudy pear juice. The pear juice was then treated with Viscozyme, gelatin and bentonite, and filtered through an ultrafiltration membrane to produce a clear pear juice. The clear pear juice was concentrated to 3 to 5 fold by vacuum evaporation, freeze concentration, and reverse osmosis methods. The concentrates were diluted to 10° Brix and stored at 4C for 15 days. The single strength juice was evaluated for color, turbidity, heat stability, and sensory preference at 5 day intervals during storage.The pear juice concentrated by the three methods showed only small differences in quality. While the clear pear juice with added ascorbic acid had no quality changes at 4C after 15 days' storage, that without the addition of ascorbic acid resulted in some deterioration in browning, turbidity and heat stability after 10 days' storage. There were small, but significant flavor differences among clear pear juices concentrated by evaporation, freeze concentration and reverse osmosis.

Enzymic release of cellobiose from sugar beet pulp, and its use to favour vanillin production in Pycnoporus cinnabarinus from vanillic acid

This study was undertaken in order to optimise the release of cellobiose from sugar beet pulp by enzymic treatment, and to evaluate the effect of this cellobiose in activating the vanillin production by filamentous fungi. Cellulose-rich residues were obtained from sugar beet pulp by a pectinase treatment, and they were then hydrolysed by a commercial cellulase. Various pretreatments (drying, grinding) and storage were applied, in order to modify the physical state of the cellulose-rich residues, such as degree of crystallinity of cellulose. After cellulase treatment, 51–64% of the initial cellulose was degraded into cellobiose and glucose, depending on the pretreatment. Whatever the pretreatment applied, cellobiose was maximally produced after 2–4 h of hydrolysis. Thereafter, cellobiose was degraded by the β-glucosidase present in the commercial cellulase, but this activity could be inhibited by the addition of d-glucono-δ-lactone. Only in some cases, could the extent of degradation of cellulose be related to the physical state of cellulose-rich residues. The best conditions were used to produce large quantities of cellobiose in order to test its influence in the bioconversion of vanillic acid into vanillin by the filamentous fungus, Pycnoporus cinnabarinus. Addition of cellobiose to a 3-day-old culture yielded a 3.3-fold increase in vanillin production when compared to a control culture devoid of cellobiose.

Enhanced bioconversion of vanillic acid into vanillin by the use of ?natural? cellobiose

Cellulose-rich residue was obtained by a pectinase treatment of sugar beet pulp and was enzymatically degraded to produce cellobiose. From sugar beet pulp, the hydrolysis yielded 5.3% of cellobiose and 3.8% of glucose. The cellobiose-rich fraction was added in a culture medium of the filamentous fungus Pycnoporus cinnabarinus to test it as an activator of vanillin production. Adding the sugar beet-derived cellobiose-rich fraction to a 3-day-old culture yielded a 3.3-fold increase in vanillin production when compared to a culture devoid of cellobiose, while commercial cellobiose yielded a 3.1-fold increase.

Changes in Apple Juice Flavor Compounds During Processing

ABSTRACTApple juice flavor fractions were collected at several stages during a commercial process. Replicated experiments were designed to collect samples from untreated pulp, from enzyme treated pulp, after pectinase treatment, after microfiltration (MF), and after pasteurization. Additional juice heating experiments were carried out. Six apple juice flavor compounds were identified based on to retention times and reported studies. The flavor profile changed at the different stages of the production line. Temperatures used (∼57.2°C) for enzyme activation and MF tended to increase flavor compounds in apple juice except iso‐butyl acetate. The higher temperatures used (∼85°C) for pasteurization decreased all flavor compounds except propyl butyrate which increased. Results indicate apple juice may contain heat activated precursors of identified flavor compounds.