Galacturonic Acid Content Research Articles

Propiedades estructurales, fisicoquímicas y emulsionantes de la pectina obtenida por extracción acuosa de la cascara de la pitaya roja (Hylocereus polyrhizus)

This work aimed to carry out a straightforward aqueous extraction of pectin from red pitaya peels (RPP), in a drive to promote the circular economy of the settlements where the fruit of this endemic species grows. The average pectin yield was 11.59 g/100 g dry basis, the degree of esterification was 60.35±1.35%, the galacturonic acid content was 54.36±1.03%, and the protein content of 5.86 ± 0.25%. The RPP pectin was analyzed in terms of physicochemical, functional, and structural features. The FTIR spectrum confirmed that the unveiled pectin structure was consistent with that reported for commercial pectins from different botanical sources. Pectin aqueous dispersions exhibited power-law shear thinning behaviour. Corn oil (10 mL) in 150 mL aqueous pectin solutions (0.12, 0.15, 0.30, 0.60 and 0.90%, w/v) emulsions exhibited increasing emulsifying activity and emulsifying stability with increased pectin concentration. The small It was concluded that the RPP pectin is an alternative potential new source of pectin for use in the formation and stabilization of oil-in-water food emulsions.

Microwave-assisted extraction of pectin from grape pomace

The utilization of microwave technique for the pectin extraction from grape pomace (Fetească Neagră and Rară Neagră), its influence on yield, galacturonic acid content, degree of esterification and molecular weight of pectin were analyzed. The optimal conditions of the extraction process were microwave power of 560 W, pH of 1.8 for 120 s. The pectin samples extracted by MAE in optimal conditions were analyzed by comparing with commercial apple and citrus pectin based on FT-IR analysis, thermal behavior, rheological characteristics and microstructure. The FT-IR analysis established the presence of different functional groups which are attributed to the finger print region of extracted pectin, while the rheological behavior presented a good viscoelasticity of pectin solutions. The obtained data assumes that grape pomace has a great potential to be a valuable source of pectin which can be extracted by simple and quick techniques, while maintaining analogous quality to conventional sources of pectin.

Comparative Characterization and Immunomodulatory Activities of Polysaccharides Extracted from the Radix of Platycodon grandiflorum with Different Extraction Methods.

Platycodon grandiflorum is an edible and medicinal plant, and polysaccharides are one of its important components. To further improve the utilization rate of P. grandiflorum, we investigated the effects of four different extraction methods, including hot water, ultrasonic-assisted, acid-assisted, and alkali-assisted extractions, on the polysaccharides, which were named PG-H, PG-U, PG-C, and PG-A. The findings indicated that the extraction method had a significant impact on the yield, characteristics, and immunoregulatory activity. We observed that the yields decreased in the following order: PG-H, PG-U, PG-C, and PG-A. Galacturonic acid, glucose, galactose, and arabinose were the most prevalent monosaccharides in the four PGs. However, their proportions varied. In addition, the difference between the content of glucose and galacturonic acid was more significant. PG-U had the highest glucose content, whereas PG-C had the lowest. Galacturonic acid content was highest in PG-A, while the lowest in PG-U. The molecular weight decreased in the order of PG-U, PG-H, PG-C, and PG-A; the particle size was in the order of PG-U, PG-A, PG-H, and PG-C. Moreover, the extraction method had a great impact on immunoregulatory activity. The ability to stimulate the immune function of macrophages was as follows: PG-A > PG-C > PG-U > PG-H. The results indicated that PGs, with lower molecular weights and higher GalA content, exhibited better immune-stimulating activity. And more important the AAE method was a good way to extract polysaccharides from Platycodon grandiflorum for use as a functional product and immunological adjuvant.

Extraction optimization and characterization of pectin from sesame (Sesamum indicum L.) capsule as a new neglected by-product.

With production of over 6 million tonnes a year of sesame, its capsules are considered to be an unutilized waste. In this study, extraction of pectin from this novel source was optimized using a green method, and the functional and physiochemical characteristics of the resultant pectin were compared to commercial pectin. In this study, the sesame capsule pectin (SCP) extraction conditions were optimized to reach maximum yield, and the results showed that the maximum pectin extraction yield (138 g kg-1 ) was obtained under optimal conditions (microwave power 700 W, irradiation time 5 min, pH 1.5, and liquid-to-solid ratio 41.8 (mL g-1 ). The results showed that the pectin was low methoxyl type with a galacturonic acid content of 670 g kg-1 . The extracted pectin had a high molecular weight (341 kDa) and surface charge (34.09 ± 1.88 mV) and exhibited 66% DPPH radical scavenging. The obtained results from 1 H-nuclear magnetic resonance and Fourier transform infrared spectra validated the presence of pectin structure in the extracted sample. Sesame capsule pectin, when compared to commercial pectin, demonstrated better functional properties in terms of emulsifying properties, oil holding capacity, foaming capacity and antioxidant activity. SCP showed similar properties in comparison to its commercial counterpart, which suggests that it could well be considered as a new and suitable source for pectin extraction. © 2022 Society of Chemical Industry.

Pistachio hull as an alternative pectin source: its extraction and use in oil in water emulsion system

In this study, pectin was extracted from the pistachio hull using two methods: conventional extraction and ultrasound-assisted extraction. Water and citric acid solution were tested separately as extraction solvents in both conventional and ultrasound methods. The highest yield (32.3 ± 1.44%) was obtained using a citric acid solution in the conventional extraction method. The pectin extracted with this method had 38.94 g acid per 100 g dry pectin extract. The galacturonic acid and ash contents were 65.81 ± 1.51 and 1.57 ± 0.03%, respectively. The pistachio hull pectin was under the low methoxy pectin group with a 19.29 ± 0.41% degree of esterification. The emulsifying property of the pectin extracted was investigated in an oil-in-water emulsion system at six different pectin concentrations (2, 4, 5, 6, 8, and 10% w/w) and at a fixed oil ratio (20% w/w). Emulsion performance was investigated in terms of emulsion stability, microstructural characteristics, droplet size, and rheological properties. The most stable emulsion was obtained at a 6% pectin concentration. The emulsifying activity index, emulsion stability index, droplet size, consistency index, and flow behavior index were 172.85 ± 0.59 m2/g, 158.28 ± 3.41 min, 6.08 ± 0.04 µm, 0.72 ± 0.001 Pa·s n , and 0.752 ± 0.005 at this concentration, respectively.

Phenolic compounds and polysaccharides in the date fruit (Phoenix dactylifera L.): Comparative study on five widely consumed Arabian varieties

The study analysed polysaccharides and phenolic compounds in widely consumed but little studied date fruits varieties such as Sukkari, Ajwa, Segae, Barrny and Khalas harvested at Tamr stage. The total phenols were in similar amount in the five varieties and ranged from 20 to 50 mg/100 g DW. The decoction and successive centrifugation made it possible to collect two main polysaccharide fractions for all the selected fruits. For each variety the first fraction was more abundant, with a lower swelling capacity and a higher amount of galacturonic acid (28.3% to 40.1%). The second fraction was only soluble in alkaline solution, with an average galacturonic acid content of only 17%. The different structure of the two polysaccharide fractions was also confirmed by the composition in neutral sugars and the degrees of methylation and acetylation. The proposed extraction procedure could be applied for larger scale extraction of the date fruit polysaccharides.

Sequential extraction, preliminary characterization and functional properties of sesame (Sesamum indicum L.) hull polysaccharides

To expand the applications of sesame hull waste produced from industrial processing, five cell wall polysaccharide fractions of sesame hulls were sequentially extracted with water (WSP), chelator (CSP), sodium carbonate (NSP), 1 mol/L potassium hydroxide (KS1), and 4 mol/L potassium hydroxide (KS4). The preliminary structural characteristics of the five polysaccharide fractions were investigated by analytical techniques, such as sugar composition analysis, UV–vis, FT-IR, molecular weight measurement, and HSQC. The results showed that CSP had the main chain of xylogalacturonans and the content of galacturonic acid reached 70.07 g/100 g. Both KS1 and KS4 had xyloglucans backbones. NSP had the lowest molecular weight and the best thermal stability, while KS4 had the highest molecular weight. Rheological measurement indicated KS4 had the highest viscosity. The antioxidant abilities of NSP and KS1 were stronger than the other three fractions. This study provides valuable new information about the structural and functional properties of cell wall polysaccharides from sesame hulls.

Effects of high‐pressure pretreatment on acid extraction of pectin from pomelo peel

SummaryTo explore the effects of high‐pressure processing (HPP) pretreatment on pectin extraction from pomelo albedo, the extraction yield, and characteristics of pectin were compared with those obtained via traditional acid (A‐pectin) extraction. Three different pressures (300, 450, and 600 MPa) and holding times (0, 5, and 10 min) were applied to the fresh albedo, followed by acid extraction. The yield, degree of esterification (DE), galacturonic acid (GalA) content, Fourier transform‐infrared (FT‐IR) spectra, and rheological properties of pectin were investigated. By comparison with A‐pectin, the yield increased by more than two and four times at 300 MPa at holding times of 5 and 10 min, respectively. All extracted pectins were high methoxyl pectins (DE of 76.30–87.83%) with high GalA content (62.3–86.60%); however, there were significant decreases in DE and GalA content when pressure was increased to 600 MPa in comparison with A‐pectin. The pressure level and holding time significantly influenced the viscosity of pectin, and HPP‐pectin 300‐5, 450‐10, and 600‐0 exhibited a much higher viscosity than A‐pectin. Consequently, this study demonstrated that HPP pretreatment of fresh albedo can increase extraction yield and/or alter pectin characteristics for further industrial applications.

New valorization approach of Algerian dates (Phoenix dactylifera L.) by ultrasound pectin extraction: Physicochemical, techno-functional, antioxidant and antidiabetic properties

To exploit the great fortune of date fruits, the current study aimed to valorize an Algerian common variety by extracting pectins. Response surface methodology (RSM) was applied as process optimization tool to achieve the highest yield using ultrasound-assisted extraction (UAE) as compared to conventional acid extraction (CAE). The experimental yield value (6.7%) was well matched with the predicted one (6.6%) at the optimum conditions (60 °C, 90 min, pH 1.5), confirming the validity of the model. The evaluation of the monomeric composition showed higher content of galacturonic acid and lower of neutral sugars in UAE pectin, as compared to CAE pectin. Conventional treatments decreased the molecular weight (Mw) of the extracted pectins (539 kDa) in a higher extent than ultrasound treatment (800 kDa). Fourier-Transform Infrared Spectroscopy (FT-IR) spectral analysis showed that both samples were low-methoxyl pectins. CAE gave rise to pectins with slightly upper technological samples in terms of water and oil holding capacity (5.2 and 3.8 g/g, respectively), and emulsifying activity (38.5 m2/g). Moreover, date pectins obtained by UAE presented enhanced antioxidant activity (24.3 and 61.0 mg/g DW for DPPH and FRAP assays, respectively), and in vitro antidiabetic properties, showing higher glucose adsorption capacity (4 mmol g−1 at 200 min), as well as α-amylase inhibition (73.7%) and potential capacity to decrease glucose diffusion (1.4 mmol mM g−1 at 150 min), which could improve the ability to retard starch digestion (0.1 mmol mM g-1 at 150 min), providing potential health-promoting properties.

A Comparative Assessment on the Recovery of Pectin and Phenolic Fractions from Aqueous and DES Extracts Obtained from Melon Peels

This work evaluates the purification of melon peel extracts obtained by two eco-friendly methods: autohydrolysis and sodium acetate/urea/water extraction (1:3:1.6), an alkaline deep eutectic solvent (DES). For that, sequential ethanol precipitation and resin adsorption/desorption stages were proposed for the separate recovery of the pectic and phenolic fractions. In order to screen the optimal purification conditions, in a first step, the effect of ethanol concentrations (from 70 to 85%) on the precipitation of pectic oligosaccharides was assayed. Subsequently, the influence of the selected resin (Amberlite XAD4, XAD16HP and XAD7HP), liquid/resin ratios, and desorption sequences (varying ethanol concentrations and pH) on the phenolic compounds was also studied. The highest pectin yields were achieved with 85% ethanol: 16.11 and 18.05 g pectin/100 g water-insoluble solids (WIS) for autohydrolysis and DES extracts, respectively. All pectins presented a galacturonic acid content of about 45%, while autohydrolysis pectin presented a higher amount of neutral sugar side chains. The presence of low methoxyl GalA and both linear and branched OGalA with DP from 2 to 20 was also confirmed by FTIR and HPAEC-PAD analysis, respectively. Concerning the phenolic fraction, the resin adsorption and desorption steps at the selected conditions (XAD4 resin, liquid/resin ratio of 2 mL/g, eluted with 50% ethanol thrice) resulted in 79.55 and 4.08 mg GAE/g non-volatile content (NVC) for autohydrolysis and DES extracts, respectively, with improved antioxidant capacity. Moreover, some phenolic acids (protocatechuic and ferulic acids) and flavonoids (orientin, vitexin and naringenin) were quantified in the extracts by HPLC–PDA-MS/MS.

The effect of sonication-synergistic natural deep eutectic solvents on extraction yield, structural and physicochemical properties of pectins extracted from mango peels

In this study, eco-friendly deep eutectic solvents (DESs) were used as extracting agents for the first time in the extraction of pectins from mango peel. Two novel green solvents including betaine-citric acid (Bet-CA) and choline chloride-malic acid (ChCl-MaA) were screened, and the extraction conditions were further optimized by full factor design experimental along with RSM. In addition, ultrasound treatment also had an influence on extraction yield, structural and physicochemical properties of extracted pectins. Two DES-extracted pectins had significantly higher yield, larger molecular weight and particles size than HCl-extracted pectin. High intensity ultrasound power enhanced the yield of low-ester pectins, but decreased the molecular weight and particles size of the pectins extracted. Monosaccharide compositions analysis showed that higher content of galacturonic acid (GalA) and larger HG region were observed in two DESs-extracted pectins. Fourier transform infrared spectra (FT-IR) of all pectins extracted were similar, with slight differences. Two DESs-extracted pectins exhibited higher DE values than HCl-extracted pectin. Thermal analysis and zeta potential results showed that HCl-extracted pectin had better stability than ChCl-MaA-extracted pectin. Additionally, HCl-extracted pectin had higher viscosity properties than two DESs-extracted pectins or commercial pectin (CP). Moreover, it was found that HCl-extracted pectin was in a colloid state, while two DESs-extracted pectins or CP were in a flow state. Ultrasound treatment significantly improved the yields of pectin/low-ester pectin. Additionally, ultrasound treatment remarkably decreased the viscosity and viscoelastic properties of the pectins extracted. The results were conducive to our understanding of the relationship between extraction conditions and physicochemical properties of the pectins extracted, which provides theoretical basis for the functional application of mango peel pectins in the food and pharmaceutical industry.

Structural characterization and hypolipidemic activity of Gracilaria lemaneiformis polysaccharide and its degradation products

This research aimed to analyze structural characterization and hypolipidemic activity in vitro of G. lemaneiformis polysaccharide (GLP) and its degradation products. The results presented that the content of galacturonic acid declined and glucuronic acid level enhanced, average particle size decreased from 99.9μm to 25.7μm, and color brightness of polysaccharide strengthened after degraded by H2O2-Vc. There was no significant change in thermal stability of polysaccharide before and after degradation. It was observed in AFM analysis, polysaccharide changed to smaller, delicacy and dispersion after degradation. As seen in FT-IR, H2O2-Vc degradation never change the structure of polysaccharide. Polysaccharide and its degradation products showed a significant inhibition effect on pancreatic lipase and cholesterol esterase in a dose-dependent manner, which presented the mixed type of competitive and non-competitive for pancreatic lipase, and non-competitive for cholesterol esterase, respectively. The fluorescence quenching type was static on pancreatic lipase and dynamic on cholesterol esterase.

Ultrasound assisted extraction of pectin from banana peel waste as a potential source for pectin production.

Large quantities of banana peels are discarded as waste or used as cattle feed or fertilisers. Moreover, the use of banana peel waste is considered to be a valuable polysaccharide like pectin that is valued by both pharmaceutical and food industries. It is well known that pectin is a high-value functional food ingredient widely used due to its special functional properties. Pectin was extracted from banana peel waste using ultrasound assisted extraction (UAE) and the extraction was optimised by response surface methodology. The independent variables such as extraction temperature, sonication time and pH of a solution were used in the range of 35–45°C, 10–20 min, and 1–3, respectively. The overall optimal conditions of multiple responses were achieved at an extraction temperature of 33.12°C, sonication time of 17.12 min and pH of 3.68. Under these conditions, the predicted value of pectin yield, the degree of esterification and galacturonic acid content, were 2.62%, 88.26% and 87%, respectively. The experimental values were well correlated with the predicted values and revealed a satisfactory validation through real-time experiments, which was accomplished at optimised conditions. The physico-chemical properties of extracted pectin using optimal conditions were comparable to commercial pectin. The results obtained revealed that pectin was effectively extracted from the banana peel waste using UAE, which confirmed that it has potential as a source for the food, beverage and pharmaceutical industries. Further studies should be conducted to improve the quality of pectin and explore the bioactivity potential of pectin such as antimicrobial, prebiotic and antioxidant properties.

The Influence of Extraction Conditions on the Yield and Physico-Chemical Parameters of Pectin from Grape Pomace.

Grape pomace is one of the most abundant by-products generated from the wine industry. This by-product is a complex substrate consisted of polysaccharides, proanthocyanidins, acid pectic substances, structural proteins, lignin, and polyphenols. In an effort to valorize this material, the present study focused on the influence of extraction conditions on the yield and physico-chemical parameters of pectin. The following conditions, such as grape pomace variety (Fetească Neagră and Rară Neagră), acid type (citric, sulfuric, and nitric), particle size intervals (<125 µm, ≥125–<200 µm and ≥200–<300 µm), temperature (70, 80 and 90 °C), pH (1, 2 and 3), and extraction time (1, 2, and 3 h) were established in order to optimize the extraction of pectin. The results showed that acid type, particle size intervals, temperature, time, and pH had a significant influence on the yield and physico-chemical parameters of pectin extracted from grape pomace. According to the obtained results, the highest yield, galacturonic acid content, degree of esterification, methoxyl content, molecular, and equivalent weight of pectin were acquired for the extraction with citric acid at pH 2, particle size interval of ≥125–<200 µm, and temperature of 90 °C for 3 h. FT-IR analysis confirmed the presence of functional groups in the fingerprint region of identification for polysaccharide in the extracted pectin.

Comparison of characterization and antioxidant activity of different citrus peel pectins

Pectins obtained from citrus peel of different cultivars and growth regions were compared based on physicochemical properties and antioxidant activity in vitro. The physicochemical features were elucidated using Fourier transform infrared (FT-IR), molecular weight distribution, monosaccharide composition, thermal behaviors and flow behaviors. Results showed that the different cultivars and growing areas have significant effects on the properties of citrus peel pectins (CPPs). Citrus peel pectins extracted by acetic acid were highly heterogeneous polysaccharides with broad molecular weight distributions and had high proportions of the RG-I domain. Among the 10 kinds of citrus peel pectins, Shatangju (CPP-6) and Xuecheng (CPP-7) own superior antioxidant biological activity and Dahongpao (CPP-3) and Buzhihuo (CPP-9) had excellent functional properties (thermal stability and viscosity). According to the correlation analysis, molecular weight, galacturonic acid content and degree of methyl-esterification were beneficial to increase the thermal stability and viscosity of citrus peel pectins, while the rhamnose content, rhamnogalacturonan I region and lower molecular weight can improve citrus peel pectins antioxidant activity. Our findings suggest that CPP-6 and CPP-7 may be useful as a potential natural antioxidant in pharmaceutical and cosmetic industries. Meanwhile, CPP-3 has great application potential in high temperature food and CPP-9 can be used as a thickener or stabilizer in the food industry.

Inhibition of Liver Cancer HepG2 Cell Proliferation by Enzymatically Prepared Low-molecular Citrus Pectin.

Low-molecular citrus pectin (LCP) is a pectin polysaccharide with low molec-ular weight, low degree of crux, and no branching. It is obtained by degrading natural citrus pectin (CP) through physical, chemical and enzymatic methods. LCP has received considerable attention in recent years due to its potential applications in the medical and biological fields. In our previous study, LCP was prepared from CP by using recombinant Bacillus subtilis pectate lyase B. Monosaccharide comparative analysis revealed that the galacturonic acid content of LCP was higher than that of CP. The cell viability effect of LCP was elucidated by using HepG2 cells and the Cell Counting Kit-8 (CCK-8) assay. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining, Annexin V-FITC/PI staining, and flow cytometer propidium iodide stain-ing were performed to detect the effects of LCP on apoptosis and cell cycle arrest in HepG2 cells. Mi-tochondrial membrane potential (MMP) was observed through 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine assay. The Mw of the prepared LCP was 7.6 kDa, which was significantly lower than that of CP (140 kDa). Cell viability decreased with the increase in the concentration of LCP. The half-inhibitory concentration of 1.46 ± 0.02 mg/mL was determined. Treatment with 1.6 mg/mL LCP in-duced the apoptosis of HepG2 cells with the inhibition rate of 83.10% ± 4.72%, and the cell cycle was arrested in the S phase. Furthermore, the MMP of HepG2 cells decreased with the increase in LCP concentration. The enzymatically prepared LCP could inhibit the proliferation of HepG2 cells. This study provided a partial experimental basis and reference for LCP to become a potential functional food for anti-liver cancer.

Study on textural changes and pectin degradation of tarocco blood Orange during storage

ABSTRACT Pectin degradation in the cell walls and middle lamella greatly affects the texture and the quality of the fruit including the taste and storage time. This directly affects its acceptability, supply to the consumer market, and economic benefits. It is therefore essential to establish the relationship between the chemical changes of pectin and the texture of the fruit to improve its preservation. This study was designed to evaluate the degradation of pectin in the peels of Tarocco blood orange and the textural changes during postharvest storage and further investigate their relationship over the study period. The texture of the fruit was characterized using the texture profile analyzer and the degradation of pectin was investigated by testing the content of the pectin, degree of esterification, and galacturonic acid content. The physicochemical properties, such as weight loss, moisture content, and anthocyanin content were also measured. Furthermore, the structural changes of the pectin were analyzed by molecular weight determination and FTIR test. The results showed that the Mw of pectin decreased from 568.05 kDa to 362.55 kDa, with a 42.1% decline in pectin content for storing for 63 d. The gradual solubilization, depolymerization, and de-esterification of the pectin consequently led to the decline in the textual properties of the fruit during postharvest storage. This can be applied and lead to improvements in quality control and process design in the food industry and the marketplace for the fruit during storage and preservation.

Pectin from Duckweed (Lemnaceae) As Potential Commercial Pectin and Its Gelling Function in Food Production: A Review

Duckweed, a small flowering plant which comes from Lemnaceae family, has been rising in popularity to many researches and applications for its numerous valuable functional properties. One of its special features is fast growing plant and easily adapted to various types of regions which makes it attractive to be manipulated in many applications including in biofuel production, waste water treatment and also for pharmaceutical and medicinal purposes. Pectin is the common component found in plant cell wall and it has been used as food additive for its capability to gel, emulsify and stabilize food products. Several requirements for commercial pectin such as galacturonic acid content (GalA) and degree of amidation have been regulated. Studies have proven that duckweed have significant amount of pectin which make it as a potential source of gelling agent in food industry. However, the structural properties of pectin from duckweed need to be investigated, in order to ensure if they meet the regulated requirements for industrial production. It is also to determine the suitability of duckweed pectin utilization in different type of food products since pectin of different sources have different structural characteristics, thus exhibit different gelling capability. This present review discusses on the potential of pectin from duckweed species to be utilized as food additive with gelling function in food products. Several extraction methods also have been reviewed, which each of them showed different efficiency and affect the extracted pectin characteristics.

Pectin from Duckweed (Lemnaceae) As Potential Commercial Pectin and Its Gelling Function in Food Production: A Review

Duckweed, a small flowering plant which comes from Lemnaceae family, has been rising in popularity to many researches and applications for its numerous valuable functional properties. One of its special features is fast growing plant and easily adapted to various types of regions which makes it attractive to be manipulated in many applications including in biofuel production, waste water treatment and also for pharmaceutical and medicinal purposes. Pectin is the common component found in plant cell wall and it has been used as food additive for its capability to gel, emulsify and stabilize food products. Several requirements for commercial pectin such as galacturonic acid content (GalA) and degree of amidation have been regulated. Studies have proven that duckweed have significant amount of pectin which make it as a potential source of gelling agent in food industry. However, the structural properties of pectin from duckweed need to be investigated, in order to ensure if they meet the regulated requirements for industrial production. It is also to determine the suitability of duckweed pectin utilization in different type of food products since pectin of different sources have different structural characteristics, thus exhibit different gelling capability. This present review discusses on the potential of pectin from duckweed species to be utilized as food additive with gelling function in food products. Several extraction methods also have been reviewed, which each of them showed different efficiency and affect the extracted pectin characteristics.

Effect of Ultrasound-Assisted, Microwave-Assisted and Ultrasound-Microwave-Assisted Extraction on Pectin Extraction from Industrial Tomato Waste

This work aimed to study the effect of ultrasound-assisted (UAE), microwave-assisted (MAE), and ultrasound-microwave-assisted (UMAE) methods for pectin extraction from industrial tomato waste. The overall performance index from the fuzzy analytical method with three criteria, pectin yield, galacturonic acid, and lycopene content, was applied to evaluate the best extraction conditions by using the weight of 75, 20, and 5, respectively. The UAE conditions was performed at a temperature of 80 °C for 20 min with the variations in the extraction pH and the solid liquid (SL) ratio. The best UAE conditions with high pectin yield, and high total carboxyl group, as well as a lycopene content, was the pH of 1.5 and the SL ratio of 1:30. The MAE conditions was performed with variations in the microwave powers and times. The results showed that the best MAE conditions were 300 W for 10 min, which gave high pectin yield with high galacturonic acid and lycopene content. Various conditions of UMAE at the best conditions of MAE and UAE were performed and exhibited that the UAE had more positively affected the pectin yield. However, the FTIR spectra of obtained pectins from different extraction techniques showed a similar pectin structure.