Properties of pectin extracted from fermented and steeped hawthorn wine pomace: A comparison

The influence of pH and calcium ions on the gelation of low methoxy pectin from potato

In this study, pectin was extracted from potato with the hydrolysis of cellulose, as well as its acid-induced and Ca2+-induced gelation behavior was investigated, too. The gelation process of unhydrolyzed pectin might be used as a model for studying the gelation behavior and characteristic of pectin within the cell wall. The results showed that potato pectin solution (3%) could form a gel state at a minimal concentration of 0.25% CaCl2 or a maximum pH value of 4.60. Furthermore, acetic acid-induced and CaCl2-induced gels were both concentration-independent. Specifically, the gel strength increased with decreasing levels of pH and increasing concentrations of CaCl2. Moreover, CaCl2-induced gels exhibited superior gelation characteristics with a higher storage modulus (7.2 Pa), larger fractal dimension (2.58), smaller porosity (12.11%), shorter relaxation time T2, and a denser gel network structure. This disparity stemmed from different mechanism: acetic acid provided H+ to combine with free carboxyl groups on the pectin chains, reducing the repulsion between pectin molecules, narrowing chain spacing, and fostering hydrogen bond formation; whereas CaCl2 promoted gelation primarily via the information of the "egg box" structure involving non-covalent bonded calcium bridges. This research could provide a theoretical basis for acid-induced and Ca2+-induced gelation of unhydrolyzed pectin extracted from the cell wall.

Antianemic Activity, Inhibition of Oxidative Stress, and Iron Supplementation in Mice with Iron-Deficiency Anemia through HG-Hawthorn Pectin-Iron(III) Complexes

In this study, we initially assessed the antioxidant activities of various HG-type hawthorn pectin-iron(III) complexes, which were synthesized in our previous research, utilizing methods such as reducing assay, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and scavenging, and hydroxyl radical scavenging. The results showed that the antioxidant capacity of the hawthorn pectin iron(III) complexes exhibited a positive correlation with increasing concentrations, ranging from 0.2 to 1.0 mg/mL. Notably, the pectin complex chelated with iron via ultrasonic extraction and de-esterification for 20 min (designated as DU20-Fe) showed the most significant antioxidant activity. Subsequently, DU20-Fe was chosen for in vivo activity assessment in a mouse model of iron-deficiency anemia (IDA). The findings indicated that DU20-Fe significantly enhanced levels of red blood cells (RBC), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) content in the mice with IDA. Furthermore, histological analysis of the liver demonstrated that DU20-Fe effectively alleviated liver damage in the IDA mice. These results validate the potential of hawthorn pectin-iron complexes in exhibiting anti-iron-deficiency anemia activity, suggesting that the hawthorn pectin-iron(III) complex may be developed into a bio-polysaccharide-based iron supplement with multiple health benefits.

Physicochemical Properties and Biological Activities of Polysaccharides from Panax Notoginseng Separated by Fractional Precipitation

The dried root of Panax notoginseng is a medicinal and food ingredient. P. notoginseng polysaccharides (PNPs) have physicochemical properties, which have not been fully elucidated. This study aimed to identify a method to separate the PNP fractions and investigate their activities. PNPs were prepared from roots by hot water extraction, deproteinization, and decolorization. PNP20, PNP40, and PNP60 fractions were isolated through stepwise ethanol precipitation at 20 %, 40 %, and 60 % concentrations, respectively. The three polysaccharide fractions were characterized using chromatography, spectroscopy, and thermogravimetric analysis, and their moisture retention, antioxidant, and tyrosinase-inhibition properties were evaluated. Monosaccharide composition analysis showed that the three PNPs contained mannose (Man), galacturonic acid (GalA), glucose (Glc), galactose (Gal), and arabinose (Ara) in different molar ratios. HPGPC analysis demonstrated that the polysaccharides precipitated with higher ethanol concentrations had lower molecular weights (Mw). Furthermore, all PNPs had distinct moisturizing and hygroscopic properties and antioxidant activities, with PNP60 showing better antioxidant properties and a competitive mixture of hygroscopic properties and tyrosinase inhibition. The chemical composition and structural characteristics of PNPs could affect their functional attributes. PNP60 has the potential to be a moisturizer and antioxidant and could be used in the development of cosmetic ingredients.

Review of the recent advances in polysaccharides from Ficus carica: Extraction, purification, structural characteristics, bioactivities and potential applications

Ficus carica (F. carica), commonly referred to as the fig tree, has received considerable attention due to its delectable and nutritious fruits. F. carica polysaccharides (FPs) are one of the key bioactive constituents of F. carica, demonstrating various biological activities such as antioxidative, immunomodulatory, anti-inflammatory, and antitumor effects, among others. Nevertheless, the extraction and purification techniques for FPs still require innovations to address their structural characteristics in order to elucidate the intricate mechanisms affecting their biological activities. Given this, the current review systematically summarizes the recent advancements in FPs, covering extraction, purification, structural characteristics, bioactivities, structure-activity relationships (SARs), current applications, challenges and future prospects. The composition of FPs predominantly includes Glu, Gal, and Rha, with a broad molecular weight distribution (ranging from 21.9 kDa to 6890 kDa). The SARs analysis suggests that the bioactivities of FPs are closely linked to their monosaccharide composition, molecular weight, uronic acid content, and configuration characteristics, underscoring the significant role of FPs in driving the development of novel bioactive compounds in the health, food, and medical sectors. In conclusion, this review would contribute the valuable research insights and provide the updated information to foster the advancement of FPs for diverse therapeutic and industrial applications.

Sequential extraction of hawthorn pectin: An attempt to reveal their original mode of being in plants and functional properties

Hawthorn is rich in pectin, which is much higher than most cultivated fruits, but conventional extraction methods do not meet the requirements of low energy consumption and green production. Pectin in hawthorn is divided into soluble and insoluble parts, and with the ripening of hawthorn, the original pectin is converted into soluble pectin and pectic acid under the action of enzymes. Therefore, based on the characteristics of hawthorn pectin, this study sequentially extracted hawthorn pectin using water-soluble pectin (WSP) and hot acid-soluble pectin (HAP) method, verifying the feasibility of extracting hawthorn pectin with pure water at room temperature, and systematically analyzing and comparing the physicochemical properties and functional characteristics of the two methods. The combination of texture analysis and gel rheology revealed that WSP formed a more uniform and dense network structure during the gelation process. Additionally, microscopic observations and emulsification index results indicated that the emulsion prepared with WSP (WSE) had a smaller particle size and better stability. This indicates that hawthorn pectin is suitable for extraction with pure water at room temperature, which can maintain its good physical properties while reducing energy consumption, providing a new approach for the large-scale extraction of pectin in the food industry.

Differential effects of enzymatically modified Ougan (Citrus Suavissima Hort. ex Tanaka) peel pectins extracted with different methods on inhibiting the proliferation of Hela cells

Previous studies have shown that modified citrus pectin (MCP) is an anti-tumor material of food grade. In this study, two enzymatically modified Ougan (Citrus Suavissima Hort. ex Tanaka) peel pectins (EMP1 and EMP2, the ones extracted by alkali and enzymatic methods) were used to investigate their differential effects on viability and physiology of Hela cells. The results showed that EMP1 and EMP2 had 88.00 % and 81.01 % galacturonic acid, 21.31 % and 20.25 % esterification degree, 10,417 g/mol and 6416 g/mol molecular weight (Mw), 82.86 % and 50.62 % RG-I, and 8.91 % and 15.70 % HG, respectively. EMP2 had higher intensities of absorption peaks than EMP1. They were irregularly shaped, with more holes on EMP1 but more wrinkles on EMP2. Both could inhibit the growth, proliferation, migration, and invasion of HeLa cells in a concentration-dependent manner, with better efficiency in EMP2. Meanwhile, EMP2 was more efficient than EMP1 in blocking the cell cycle in S phase, resulting in apoptosis. In conclusion, the variations caused by extraction resulted in differences in anti-tumor activity of MCP and EMP2 with lower Mw and higher HG exhibited better anti-tumor effects. This study would provide an experimental basis and reference for the research and development of anti-tumor supplements from citrus pectin.

A Comprehensive Review on the Isolation, Bioactivities, and Structure-Activity Relationship of Hawthorn Pectin and Its Derived Oligosaccharides

Hawthorn (Crataegus pinnatifida Bunge) has been highlighted as an excellent source of a variety of bioactive polymers, which has attracted increasing research interest. Pectin, as a kind of soluble dietary fiber in hawthorn, is mainly extracted by hot water extraction and ultrasonic or enzymatic hydrolysis and is then extensively used in food, pharmaceutical, and nutraceutical industries. Numerous studies have shown that hawthorn pectin and its derived oligosaccharides exhibit a wide range of biological activities, such as antioxidant activity, hypolipidemic and cholesterol-reducing effects, antimicrobial activity, and intestinal function modulatory activity. As discovered, the bioactivities of hawthorn pectin and its derived oligosaccharides were mainly contributed by structural features and chemical compositions and were highly associated with the extraction methods. Additionally, hawthorn pectin is a potential resource for the development of emulsifiers and gelling agents, food packaging films, novel foods, and traditional medicines. This review provides a comprehensive summary of current research for readers on the extraction techniques, functional characteristics, structure-activity relationship, and applications in order to provide ideas and references for the investigation and utilization of hawthorn pectin and its derived oligosaccharides. Further research and development efforts are imperative to fully explore and harness the potential of hawthorn pectin-derived oligosaccharides in the food and medicine fields.

Physicochemical properties of pectin-Fe(III) gained by HG-type hawthorn with different esterification degree

In this study, the complexation ability of HG-type hawthorn pectin with trivalent iron ions after de-esterification was investigated. The moderate esterification reaction could significantly increase the iron content in HG-type hawthorn pectin. Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) experiments proved that -OH and -COOH in the pectin acted as a bridge connecting Fe3+ leading to the formation of β-FeOOH structure, and the trivalent iron ions were successfully complexed into the HG-type hawthorn pectin. In addition, infrared and ultraviolet spectroscopic scans, particle size, and potentiometric measurements were carried out to demonstrate the complexation coordination mechanism of hawthorn pectin with Fe3+, and there were differences in the complexation effect of HG-type hawthorn pectin with different degrees of esterification. The gelling properties of HG-type hawthorn pectin were subsequently verified by in vitro gastrointestinal tract simulation experiments to aid the smooth passage of ferric ions through the gastric juices and reduce irritation. The success of the experiments demonstrated that HG-type hawthorn pectin is an excellent raw material for metal complexation, and the degree of esterification is one of the important factors affecting its complexation effect, which proves its potential application value as an iron supplement.

Studies on the degradation pattern of wheat malt endo-1,4-β-xylanase on wheat-derived arabinoxylans

BACKGROUND

Wheat malt endo-1,4-β-xylanase is a key enzyme for arabinoxylan degradation, but its wheat-derived arabinoxylan degradation pattern is unclear.

RESULTS

Water-extractable arabinoxylan (WEAX) of 300-750 kDa and 30-100 kDa were the two components with the highest degradation efficiency of wheat malt endo-1,4-β-xylanase, followed by > 1000 kDa WEAX, but 100-300 kDa WEAX showed the lowest degradation efficiency. The main enzymatic products were the 5-30 kDa WEAX, which accounted for 57.57%, 68.15%, and 52.28% of WAXH, WAXM, and WAXL products, respectively. The enzymatic efficiency of wheat malt endo-1,4-β-xylanase was relatively high, and the continuity of enzymatic efficiency was good, especially since the enzymatic reaction was the most intense in 1-3 h. WEAX of > 300 kDa was highly significant and positively correlated with viscosity. In comparison, WEAX of < 30 kDa was highly significant and negatively correlated with viscosity. As the enzymatic degradation proceeded, there were fewer and fewer macromolecular components but more and more small molecule components, and the system viscosity became smaller and smaller.

CONCLUSION

In this study, it was found that wheat malt endo-1,4-β-xylanase degraded preferentially 300-750 kDa and 30-100 kDa WEAX, not in the order of substrate size in a sequential enzymatic degradation. Wheat malt endo-1,4-β-xylanase was most efficient within 3 h, primarily generating < 30 kDa WEAX ultimately. The main products were highly significantly negatively correlated with the system viscosity, so that the system viscosity gradually decreased as the enzymatic hydrolysis proceeded. © 2024 Society of Chemical Industry.

Hot-air drying vs. lyophilization of sugar beet flakes for efficient pectin recovery and influence of extraction conditions on pectin physicochemical properties

This study assessed the influence of drying pretreatment and extraction conditions (type of acid and particle size of plant material) on the yield and physicochemical properties of pectin from sugar beet flakes resulted as by-product of sugar beet processing in the sugar industry. The results indicated that the drying conditions (hot-air drying and lyophilization) affected the extraction yield, the chemical composition of pectin, its color, degree of methylation and acetylation, molecular weight, and its rheological and emulsifying properties. The best results for pectin yield (16.20%), galacturonic acid content (91.19 g/100 g), degree of methylation and acetylation (66.93 and 23.87%), and molecular weight (3.89 × 105 g/mol) were obtained when sugar beet flakes were pretreated by hot-air drying, and the extraction was made with citric acid using plant material with particle sizes of 125-200 μm. This pectin also had high emulsion activity (51.42%) and emulsion stability (88.03%). The FT-IR spectra were similar, while pectin thermal behavior was affected by the drying pretreatment and extraction conditions. The results of this study showed that from this by-product of the sugar industry it can be extracted high quality pectin with rheological and emulsifying properties that are superior to commercial citrus and apple pectin.

Chemical characterization-function relationship of pectins from persimmon fruit within different ripeness

This study investigated the structural and functional characteristics of two different molecular weight persimmon pectin extracted from unripe persimmon (PP-1) and ripe persimmon (PP-2). The molecular weight was determined as 117.8 kDa and 61.3 kDa for PP-1 and PP-2, which consisting of glucose, rhamnose, mannose, galactose, and xylose. AFM results indicated PP-1 with many linear chains, and short chains in while short chains, branching points, and heterogeneous clumps were found in PP-2.Emulsion characterization and storage stability experiments revealed that PP-1 with more stable emulsifying properties than PP-2 and commercial citrus pectin. In vitro fermentation of PP-1 and PP-2 by gut microbiota indicated that PP-1 and PP-2 groups were higher than inulin group in total SCFAs production after 48 h of fermentation. This study provided useful information for high value utilization of persimmon pectin.

Effect of Lactiplantibacillus plantarum fermentation on the physicochemical, antioxidant activity and immunomodulatory ability of polysaccharides from Lvjian okra

Okra polysaccharides exhibits a range of biological activities. To date, its processing using microbial fermentation has not been explored. This study investigated the fermentation of okra juice with various lactic acid bacteria, followed by the extraction and characterization of crude polysaccharides (termed OPS-F), in contrast to their non-fermented counterpart (OPS). Changes in physicochemical properties, antioxidant activity and immunomodulatory ability were noted. The results demonstrated that OPS-F had a 7.42-12.53 % increase in total polysaccharides content compared to OPS. However, high-performance size-exclusion chromatography indicated a reduction in the molecular weight of OPS-F (7.9-9.5 × 105 Da) relative to OPS (1.66 × 106 Da). Compared to OPS, OPS-F had reduced levels of mannose, glucose, glucuronic acid and arabinose, but increased rhamnose, galacturonic acid and galactose, exhibiting enhanced solubility and lower apparent viscosity. Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis showed minimal changes in polysaccharide structure post-fermentation. Moreover, despite a decrease in antioxidant activity post-fermentation, OPS-F exhibited superior immunomodulatory potential. In conclusion, fermenting okra juice with lactic acid bacteria alters the physicochemical properties of crude polysaccharides and enhances their immunomodulatory activity, offering a promising approach for developing new functional food resources.

Effects of Lactobacillus plantarum FM 17 fermentation on jackfruit polysaccharides: Physicochemical, structural, and bioactive properties

Fermentation is a novel technology for modifying polysaccharides in fruits and improving their bioactivities. In this work, we introduced Lactobacillus plantarum FM 17 to ferment jackfruit pulp and subsequently purified polysaccharides from unfermented (JP) and fermented jackfruit pulp (JP-F). Furthermore, the physicochemical, structural, and bioactive properties of JP and JP-F were investigated. Results showed fermentation dropped the glucuronic acid, molecular weight, and particle size of JP-F by 15.62 %, 23.92 %, and 39.43 %, respectively, compared with those of JP. JP-F showed higher solubility than JP but lower apparent viscosity and thermal stability. Additionally, FT-IR spectra and X-ray diffraction analysis showed that fermentation did not alter the different types of glycosidic bonds and the fundamental polysaccharide structure. Moreover, JP-F exhibited stronger DPPH and ABTS free radical scavenging properties than JP and stronger stimulation on macrophage secretion of NO and IL-6 in RAW 264.7 cells. Therefore, using L. plantarum FM 17 for fermentation can alter physical and chemical properties of jackfruit pulp polysaccharides, enhancing their bioactivities.

Comparative study on thermo-mechanical, structural and functional properties of pectin extracted from immature wasted apples and commercial pectin

Pectin yield of 22.22 ± 0.98 % (dry basis) was achieved from prematurely dropped Golden Delicious apples, having a light orange hue (hue value: 78.08 ± 0.04) and an overall color difference (ΔE) of 9.92 ± 0.01 compared to commercial pectin (CP). Extracted AP exhibited a lower equivalent weight (725.24 ± 29.73) and higher methoxy content (8.36 ± 0.28 %) in contrast to CP. However, a similar degree of esterification of 71.57 ± 0.79 and 70.55 ± 0.59 %, was observed in AP and CP respectively. Apple pectin demonstrated slight lower galacturonic acid (GalA) content of 68.10 ± 3.94 % in comparison to 72.31 ± 4.62 % of CP, which was further corroborated by reduced intensity in FTIR fingerprint region (912-1025 cm-1). Morphology revealed a sheet-like cloudy appearance indicating a significant presence of associated sugars whereas X-ray diffraction highlighted the highly amorphous nature of AP. AP and CP solutions (3-9 %) displayed a shear-thinning flow and viscoelastic behavior where the loss (G') moduli dominated over the storage moduli (G"). Owing to high degree of esterification, galacturonic acid content (>65 %) that aligns with commercial standards and viscoelastic behavior, the extracted AP holds promise for potential utilization in commercial applications. This study underscores the potential for sustainable utilization of prematurely dropped apples through pectin extraction, contributing to valorization of the wasted bioresource.

Optimization and characterization of pectin extracted from hawthorn by deep eutectic solvent

In this study, hawthorn pectin was extracted from dried hawthorn with deep eutectic solvent(DES) and compared with the traditional extraction methods such as acid extraction (AE) and ultrasonic-assisted extraction (UAE). Under optimal conditions, with a molar ratio of choline chloride to urea at 1:3, a water content of 30 %, a liquid-to-solid ratio of 30:1 (mL/g), an extraction temperature of 80 °C, an extraction time of 60 min, and a pH of 1, the yield of hawthorn pectin was 4.33 % ± 0.02 %. The measured results were consistent with the prediction. In addition, compared with AE and UAE, the experimental results showed that DES had a higher yield, a lower degree of esterification, and a slightly different monosaccharide composition from other extraction methods. The results of infrared spectroscopy and scanning electron microscopy showed that DES had a fine microstructure and coarser surface, and the main chemical structure of DES didn't change. The rheological analysis showed that DES had lower apparent viscosity than AE and UAE. These results represent a green source for pectin extraction with high pectin yield and good performance. In conclusion, the deep eutectic solvent has good application prospects in extracting hawthorn pectin.

Preparation, structural characterization, bioactivities, and applications of Crataegus spp. polysaccharides: A review

Crataegus, is a genus within the Rosaceae family. It is recognized as a valuable plant with both medicinal and edible qualities, earning it the epithet of the "nutritious fruit" owing to its abundant bioactive compounds. Polysaccharides are carbohydrate polymers linked by glycosidic bonds, one of the crucial bioactive ingredients of Crataegus spp. Recently, Crataegus spp. polysaccharides (CPs) have garnered considerable attention due to their diverse range of bioactivities, including prebiotic, hypolipidemic, anticancer, antibacterial, antioxidant, and immunobiological properties. Herein, we provide a comprehensive overview of recent research on CPs. The analysis revealed that CPs exhibited a broad molecular weight distribution, ranging from 5.70 Da to 4.76 × 108 Da, and are composed of various monosaccharide constituents such as mannose, rhamnose, and arabinose. Structure-activity relationships demonstrated that the biological function of CPs is closely associated with their molecular weight, galacturonic acid content, and chemical modifications. Additionally, CPs have excellent bioavailability, biocompatibility, and biodegradability, which make them promising candidates for applications in the food, medicine, and cosmetic industries. The article also scrutinized the potential development and future research directions of CPs. Overall, this article provides comprehensive knowledge and underpinnings of CPs for future research and development as therapeutic agents and multifunctional food additives.

Pectin-rich dragon fruit peel extracts: An environmentally friendly emulsifier of natural origin

Pectin extraction is generally an energy-intensive industrial process, while on the other hand their extraction methods vary from different sources. Starting with that perspective, pectin (WSP) containing ultra-low degree of methylation (31.08 ± 1.27%) from dragon fruit peel (DFP) was extracted by using pure water at room temperature. WSP, dominant in DFP (17.13 ± 1.01%), showed both a high molecular weight and a wide molecular weight distribution, while the yield of the rest acid-soluble pectin (HAP) from DFP residue was only 5.22 ± 0.76%. Furthermore, WSP can stabilize emulsions over a wide range of concentrations and oil phases, especially HIPE. Therefore, the hypothesis was verified that the pectin-rich extract from dragon fruit peel with excellent emulsifying properties could be simply extracted by pure water. This environmentally-friendly and energy-saving extraction method provides a new insight to increase the additional value of dragon fruit peel produced in food processing.

Recent advances in polysaccharide biomodification by microbial fermentation: production, properties, bioactivities, and mechanisms

Polysaccharides are natural chemical compounds that are extensively employed in the food and pharmaceutical industries. They exhibit a wide range of physical and biological properties. These properties are commonly improved by using chemical and physical methods. However, with the advancement of biotechnology and increased demand for green, clean, and safe products, polysaccharide modification via microbial fermentation has gained importance in improving their physicochemical and biological activities. The physicochemical and structural characteristics, biological activity, and modification mechanisms of microbially fermented polysaccharides were reviewed and summarized in this study. Polysaccharide modifications were categorized and discussed in terms of strains and fermentation techniques. The effects of microbial fermentation on the physicochemical characteristics of polysaccharides were highlighted. The impact of modification of polysaccharides on their antioxidant, immune, hypoglycemic, and other activities, as well as probiotic digestive enhancement, were also discussed. Finally, we investigated a potential enzyme-based process for polysaccharide modification via microbial fermentation. Modification of polysaccharides via microbial fermentation has significant value and application potential.

Physicochemical properties and Pb2+ adsorption capacity of freeze-dried hawthorn pectin fractions by gradient ethanol precipitation

Three fractions of FHP20, FHP40 and FHP60 were obtained from freeze-dried hawthorn pectin by gradient ethanol precipitation (20-60 %), and their physicochemical properties and adsorption performance on Pb²⁺ were investigated. It was found that the content of galacturonic acid (GalA) and esterification of FHP fractions gradually reduced with the increase of ethanol concentration. FHP60 had the lowest molecular weight (60.69 × 10³ Da), and the composition and proportion of monosaccharides were significantly different. The experimental results of Pb²⁺ adsorption showed that the adsorption process fitted well with the Langmuir monolayer adsorption and the pseudo-second-order models. Our findings suggested that pectin fractions with good homogeneity of molecular weight and chemical construction can be obtained by gradient ethanol precipitation, and hawthorn pectin could be developed as a potential adsorbent for Pb²⁺ removal.

Antioxidant activity and semi-solid emulsification of a polysaccharide from coffee cherry peel

In order to further improve the economic benefits of the coffee industry chain, we carried out the following systematic research on processing by-products. In this research, the obtained coffee cherry peel polysaccharide (CCP) which was removed from the coffee cherry peel by hot acid method had a galacturonic acid content of 20.50 % and a molecular weight of 3.05 kg/mol. According to the results of monosaccharide analysis, Fourier transform infrared spectroscopy, molecular weight distribution, and thermal analysis, CCP was a typical high methoxy polysaccharide. In vitro antioxidant results showed that CCP had better antioxidant capacity than commercial citrus polysaccharide (APC). When it came to emulsification performance, the water-oil bonding ability and disturbance resistance to the fluid of CCP were also significantly higher than that of APC. Specially, we found that 0.50 % (wt%) CCP could form a solid-liquid gel with very high plasticity at low oil phase fraction. In conclusion, the coffee cherry peel could be used as a natural source of a novel emulsifier, providing a promising alternative for polysaccharide in the food industry.

Characterization of hawthorn pectin gained via different ethanol concentrations

Pectin is identified as an effective delivery material due to its excellent gel-forming ability, low immunogenic properties, biocompatibility, and biodegradability. These excellent properties depend on the preparation method of pectin. In the study, four pectin fractions (named: CAHP30, CAHP40, CAHP50, and CAHP60, respectively) were obtained by different ethanol precipitations (30%, 40%, 50%, and 60%). Physicochemical properties, antioxidant activity, and emulsifying ability of HP were investigated and analyzed. Results showed that the surface structure of pectin was changed by ethanol fractional precipitation, and four fractions were low methoxy pectin. They had different monosaccharide compositions, but all rich in GalA. The Mw/Mn of CAHP30, CAHP40, CAHP50, and CAHP60 were 3.29, 2.57, 2.66, and 2.77, respectively. CAHP30 and CAHP60 had excellent emulsifying ability; moreover, CAHP60 was endowed with additional lipid antioxidant capacity and had the best thermal stability. E-CAHP40 exhibited a property between the entangled network structure. Overall, pectin with specific properties could be obtained by different ethanol concentrations.

Characterize the physicochemical properties and microstructure of pectin from high-pressure and thermal processed cloudy hawthorn (Crataegus pinnatifida) juice based on acid heating extraction

Physicochemical properties and morphological features of pectin in high-pressure-processing (JHPP) and thermal-processing (JTP) treated cloudy hawthorn juice were investigated based on acid heating extraction. Pectin from hawthorn juice was identified as low methoxy pectin (41.77%), which was significantly reduced to 34.56%-39.51% from JHPP, while pectin esterification degree (DE) from JTP increased to 45.58%, which can also be confirmed by Fourier transform infrared spectroscopy. In comparison to control, pectin linearity of JHPP and JTP significantly decreased with more highly branched-chains. However, no significate difference was observed in thermostability, crystallinity and main functional groups. Interestingly, a large number of aggregations was observed in JHPP pectin, and the intermodular distance of JTP pectin was enhanced, which was consistent with the results of viscosity, molecular weight and DE. These findings provided insights into utilization of hawthorn pectin and application of high-pressure processing (HPP) for improving quality property of fruit products by pectin modification.

Inulin-type fructans obtained from Atractylodis Macrocephalae by water/alkali extraction and immunoregulatory evaluation

Two homogenous polysaccharides extracted from Atractylodes macrocephala Koidz. were investigated by water extraction (AMP-F_W) and alkali solution extraction (AMP-F_A) after purification by anion exchange column and size exclusion chromatography. The molecular weight of AMP-F_W and AMP-F_A were 2874 Da and 3438 Da, respectively, estimated by high performance gel permeation chromatography (HPGPC). The monosaccharide compositions of AMP-F_W and AMP-F_A were glucose and fructose at a molar ratio of 0.11:0.89 determined by high performance anion exchange chromatography (HPAEC). The functional groups, glycosidic linkages and the chemical structure were characterized by FT-IR, GC-MS and NMR, which comprehensively indicated a similar inulin-type fructan structure of the two polysaccharides from A. macrocephala. However, the scanning electron microscopy (SEM) results showed different microstructures that irregular lamellar shape for the AMP-F_W and spheroid shape for the AMP-F_A. The further studies on immunomodulation showed that AMP-F_W at 50 μg/mL could significantly (P < 0.05) stimulate RAW 264.7 cells by enhancing the mRNA expression of TNF-α and IL-1β, which had a relative high immunomodulatory potential when compared to AMP-F_A. Their activation on different toll-like receptors (TLR) also indicated their different roles in the immunoregulation. Overall, these findings reported here will serve as the basis for further structure-activity relationship studies.

Pectin extracted from dragon fruit Peel: An exploration as a natural emulsifier

As a potential source of pectin, the peel of dragon fruit is a by-product of fruit processing and will bring considerable economic benefits. In this study, pectin (DFP) was extracted from dragon fruit peel by using a hot-acid method, and two commercial pectins were used as controls to correlate structural differences with physical and chemical properties through systematic evaluation. The galacturonic acid (GalA) content, degree of esterification (DM) and molecular weight (Mw) of DFP were 87.02 ± 0.89 %, 37.26 ± 1.37 % and 1181.75 ± 11.21 kDa, respectively. The FTIR and XRD analysis also confirmed that DFP is ultra-low methoxylated pectin and also contains characteristic functional groups naturally present in pectin. Compared to APA140 and LMP, DFP showed excellent emulsification at low concentrations. In particular, the extraordinary antioxidant activity of DFP may be attributed to polyphenols in free or bound form. Overall, DFP can be considered as a promising emulsifier and the results of the study provide an alternative to natural sources of emulsifiers in the food industry.

Evaluation of pectin extractions and their application in the alkaline Maillard reaction

A 2³ factorial design was used to evaluate the influence of temperature, catalyst and time and esterification degree (DE) of pectin obtained from mango, orange and tangerine peels as well as tamarind seeds by using the acid hydrolysis method. The study showed that a high temperature positively influenced the percentage of pectin yield for the four second generation biomasses. Nevertheless, the temperature showed a greater influence in the solubility and diffusion of the acid solvent in the tamarind seed matrix, resulting a pectin recovery 32.9%. Concerning the %DE, the most statistically significant value observed was dependent on the type of biomass studied. The %DE and the nature of the pectin are determining factors in the pectin's final use, in the present work the pectin extracted was used to produce furfural, a precursor of high value chemicals. The furfural production was achieved through alkaline hydrolysis and enhanced using the Maillard reaction, reaching a maximum concentration of 71.8 g/L which represents a 42.1% increase from the alkaline hydrolysis.

Extraction optimization and characterization of persimmon peel pectin extracted by subcritical water

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Persimmon peel pectin (PPP) was extracted by subcritical water.

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PPP had low M_w of 21.79 kDa and its degree of esterification was 40.61 %.

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PPP attributed to a degradation temperature of 228.05 ℃.

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The IC₅₀ of PPP to ABTS•+ was 9.8-times that of commercial citrus pectin in vitro.

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PPP altered microbial intestinal communities in mice.

Persimmon peel pectin (PPP) was extracted by subcritical water via the response surface methodology. The optimal crude PPP extraction yield of 7.62 ± 0.7 % was found at 138 °C, 2.84 min, and liquid–solid ratio of 1:10.02. After treatment of deproteinization and decolorization with papain and hydrogen peroxide, 83.19 % of protein and 78.56 % of the colour in crude PPP were removed, respectively. PPP owned the M_w of 21.79 kDa and its uronic acids content was 64.03 %. PPP was further affirmed by fourier transform infrared, X-ray diffractometer and ¹H NMR analysis. Moreover, the degradation temperature (228.05 ℃) of PPP was verified via differential scanning calorimetry. Then, the IC₅₀ of PPP to ABTS•+ was 9.8 times that of commercial citrus pectin. Moreover, PPP could change microbial communities and selectively enrich Bacteroides, Cetobacterium, Erysipelatoclostridium, Parabacteroides and Phocaeicola sartorii. This study demonstrated that subcritical water was practicable for extraction of persimmon peel pectin.

Encapsulation and sustained release of curcumin by hawthorn pectin and Tenebrio Molitor protein composite hydrogel

In this study, the effects of pH value, mixing ratio and the Ca²⁺ concentration on the complex gelation of hawthorn pectin (HP) and Tenebrio Molitor protein (TMP) were investigated. The turbidity results showed that the composite gel had the maximum polymer concentration when the mixing ratio was 2:1 and the pH value was 3.35. The rheological measurement results showed that TMP/HP (15 mmol/L) hydrogel (THIH) had the highest storage modulus and loss modulus, indicating that the properties of the hydrogel at this Ca²⁺ concentration had been significantly improved. The results of scanning electron microscope and pore size also proved that the network structure prepared under this condition was compact and uniform, the pore size was small, which was beneficial to the entrapment of active components. Subsequently, in order to explore the storage stability and antioxidant activity of THIH-loaded curcumin in simulated gastrointestinal environment, in vitro simulated digestion experiment was carried out and satisfactory results were obtained. To sum up, THIH was a promising delivery system with broad application prospects, which was expected to provide a novel idea for the entrapment and delivery of active components.

Hawthorn Juice Simulation System for Pectin and Polyphenol Adsorption Behavior: Kinetic Modeling Properties and Identification of the Interaction Mechanism

The interaction between polyphenols and polysaccharides plays an important role in increasing the turbidity stability of fruit juice and improving unpleasant sensory experiences. The binding adsorption behavior between hawthorn pectin (HP) and polyphenols (epicatechin and chlorogenic acid) accorded with the monolayer adsorption behavior driven by chemical action and were better fitted by pseudo-second order dynamic equation and Langmuir model. The HP binding sites (Qm) and adsorption capacity (Qe) to epicatechin were estimated at 75.188 and 293.627 μg/mg HP, respectively, which was about nine and twelve times higher than that of chlorogenic acid. The interaction between HP and polyphenols exhibited higher turbidity characteristics, particle size and lower zeta potential than epicatechin and chlorogenic acid alone. Meanwhile, according to Fourier Transform Infrared Spectroscopy (FT-IR) analysis, it could be speculated that the interaction between HP and polyphenols resulted in chemical combination. Moreover, ΔH < 0 and TΔS < 0, which indicated that the interaction between HP and polyphenols was mainly driven by hydrogen bonds and van der Waals forces.

Variation in characterization and probiotic activities of polysaccharides from litchi pulp fermented for different times

This study investigated the chemical structures and probiotic potential of different polysaccharides (LPs) extracted from the litchi pulp that fermented with Lactobacillus fermentum for different times (i.e., 0–72 h corresponding to LP-0 through LP-72, respectively). Fermentation times affected the yields, total sugar contents, uronic acid contents, molecular weights, and monosaccharide compositions of LPs. The LPs yields and uronic acid contents exhibited irregular trends in association with fermentation time, while total sugar contents decreased, and the molecular weights increased. Particularly, LP-6 contained the highest extraction yields (2.67%), lowest uronic acid contents, and smallest average Mw (104 kDa) (p < 0.05). Moreover, analysis of the monosaccharide composition in the fermented LPs indicated that the proportions of glucose decreased, while arabinose and galacturonic acid proportions increased relative to unfermented LP-0. Further, LP-6 demonstrated the highest growth for Bifidobacterium compared to LP-0, while the other fermentation time led to comparable or worse probiotic promoting activities. These results suggest that lactic acid bacteria fermentation alters the physicochemical properties of litchi polysaccharides, such that suitable fermentation time can enhance their probiotic activities.

Synthesis, physicochemical characterization, antibacterial activity, and biocompatibility of quaternized hawthorn pectin

Quaternized polysaccharides are considered as potential antimicrobial materials due to their antimicrobial activity, biodegradability, biocompatibility, and water solubility. In this work, hawthorn pectin (HP) was obtained by ultrasound‑sodium citrate assisted extraction, quaternized hawthorn pectin (QHP) derivatives (namely: QHP-1, QHP-2, QHP-3, and QHP-4) with different degree of substitution were produced using (3-Chloro-2-hydroxypropyl) trimethylammonium chloride under alkaline conditions. The structure, properties, and morphology of HP and QHP were characterized by FTIR, XRD, ¹H NMR, high-performance gel permeation chromatography (HPGPC), thermal analysis, and SEM. The results of FTIR and ¹H NMR demonstrated that the quaternary ammonium modification was successful, and the degree of substitution (DS) of derivatives was calculated through elemental analysis. The determination of the minimum inhibitory concentrations and biofilm inhibition assay exhibited that QHP has a certain inhibitory effect on Escherichia coli and Staphylococcus aureus. Acceptable values of QHP were obtained in cytotoxicity assay on human keratinocytes.

Effect of an endo-1,4-β-xylanase from wheat malt on water-unextractable arabinoxylan derived from wheat

BACKGROUND

Non-starch polysaccharides in wheat are dominated by arabinoxylan (AX). Endo-1,4-β-xylanase (EC 3.2.1.8) is the most important enzyme for degrading AX. This paper investigated the ability of endo-1,4-β-xylanase extracted from wheat malt to degrade non-water-extractable wheat-derived arabinoxylan (WUAX).

RESULTS

The enzyme was observed to break down wheat-derived WUAX effectively, substantially increasing the concentration of water-extractable arabinoxylan (WEAX) in the system for up to 6 h. A considerable quantity of arabinose xylooligosaccharide (AXOS) was also produced, suggesting that the enzyme could produce oligosaccharides too. The molecular weight of the product WEAX was between 23 and 27 kDa and the content of oligosaccharides changed with degradation time. This suggests that endo-1,4-β-xylanase can not only degrade WUAX into WEAX and xylooligosaccharides but can also degrade the xylooligosaccharides with larger molecular weights into xylobiose and xylotriose. The viscosity of the degradation product increased significantly in the first 2 h, then decreased with longer degradation times. The concentration of WEAX in the reaction system increased throughout the reaction but at gradually lower rates, indicating that the endo-1,4-β-xylanase degraded WEAX better than it degraded WUAX. Rheological tests showed that solutions prepared from the WEAX that was produced had properties of a pseudoplastic fluid.

CONCLUSION

The results showed that the wheat malt endo-1,4-β-xylanase, which we had previously tested on WEAX, was also effective in degrading wheat-derived WUAX. This study can therefore provide a theoretical basis for the subsequent role of the enzyme in other sources of xylan, and provide guidance for the quality control of beer in the brewing process. © 2021 Society of Chemical Industry.

Spray-Drying Microencapsulation of Pink Guava (Psidium guajava) Carotenoids Using Mucilage from Opuntia ficus-indica Cladodes and Aloe Vera Leaves as Encapsulating Materials

In this work, the capacity of the mucilage extracted from the cladodes of Opuntia ficus-indica (OFI) and aloe vera (AV) leaves as wall material in the microencapsulation of pink guava carotenoids using spray-drying was studied. The stability of the encapsulated carotenoids was quantified using UV-vis and HPLC/MS techniques. Likewise, the antioxidant activity (TEAC), color (CIELab), structural (FTIR) and microstructural (SEM and particle size) properties, as well as the total dietary content, of both types of mucilage microcapsules were determined. Our results show that the use of AV mucilage, compared to OFI mucilage, increased both the retention of β-carotene and the antioxidant capacity of the carotenoid microcapsules by around 14%, as well as the total carotenoid content (TCC) by around 26%, and also favors the formation of spherical-type particles (Ø ≅ 26 µm) without the apparent damage of a more uniform size and with an attractive red-yellow hue. This type of microcapsules is proposed as a convenient alternative means to incorporate guava carotenoids, a natural colorant with a high antioxidant capacity, and dietary fiber content in the manufacture of functional products, which is a topic of interest for the food, pharmaceutical, and cosmetic industries.

Effects of Lactobacillus plantarum Fermentation on the Chemical Structure and Antioxidant Activity of Polysaccharides from Bulbs of Lanzhou Lily

Recently, Lanzhou lily has attracted more attention because of its bioactive components specifically polysaccharides. We studied in vitro the effects of Lactobacillus plantarum fermentation on the physicochemical properties, chemical structure, and antioxidant activity of the Lanzhou lily polysaccharide. The results showed that compared with the unfermented Lanzhou lily polysaccharide (LP-W), the molecular weight (M _w) of the fermented Lanzhou lily polysaccharide (LPF-W) decreased from 4334 to 1684 kDa, the particle size decreased from 300.8 ± 6.38 to 141.9 ± 4.96 nm, and the solubility increased from 72.33 ± 3.58 to 104.27 ± 2.91 mg/mL. In addition, after fermentation, the monosaccharide composition of LPF-W changed, and the alternation of mannose residues and glucose residues disappeared. The results of the analysis of the antioxidant activity in vitro showed that compared with LP-W, the fermented LPF-W had higher DPPH radical ability, superoxide anion radical scavenging ability, and reducing efficiency, but the hydroxyl radical scavenging ability decreased. These findings provide a reference for the potential application of the lily polysaccharide as a plant-derived antioxidant in functional foods.

Characterization of Cationic Modified Short Linear Glucan and Fabrication of Complex Nanoparticles with Low and High Methoxy Pectin

In this study, we chemically modified the short linear glucan (SLG) using the 3-chloro-2-hydroxypropyl trimethylammonium chloride to introduce a positive surface charge via cationization (CSLG). We then prepared CSLG-based binary nanocomplex particles through electrostatic interactions with low and high methoxyl pectin. The two new types of binary nanocomplex were comprehensively characterized. It was found that the nanocomplex particles showed a spherical shape with the particle size of <700 nm, smooth surface, homogeneous distribution, and negative surface charge. Fourier transform infrared spectroscopy (FTIR) revealed that the driving forces to form nanocomplex were primarily electrostatic interactions and hydrogen bonding. In addition, increasing the CSLG concentration in the nanocomplex significantly enhanced both thermal stability and digestive stability. By comparing the two complex nanoparticles, the HMP-CSLG has a larger particle size and better stability under the GI condition due to the high content of the methoxy group. Additionally, the HMP-CSLG nanoparticle has a higher encapsulation efficiency and slower release rate under simulated gastrointestinal fluid for tangeretin compared with the LMP-CSLG. These results provide new insights into designing the CSLG-based nanocomplex as a potential oral delivery system for nutraceuticals or active ingredients.

Hawthorn pectin: Extraction, function and utilization

Pectin has been widely used as emulsifiers, gelling agents, glazing agents, stabilizers, and thickeners in food products. Hawthorn pectin has a higher viscosity than other foods-derived pectin such as lemon and apple pectin. It is also reported as a multifunctional fruit substance, which reduces the risk of hyperlipidemia and dyslipidemia. Therefore, hawthorn pectin is a potential resource for the development of new drugs, functional foods, and health-care products. This review symmetrically summarized the extraction methods, physiological characteristics, functional properties, and processing technologies of hawthorn pectin. It laid a foundation for the further research of hawthorn pectin and promoted the diversified utilization of hawthorn.

Extraction and Physicochemical Characterization of Dried Powder Mucilage from Opuntia ficus-indica Cladodes and Aloe Vera Leaves: A Comparative Study

Cactaceae and Asphodelaceae are native desert plants known for their high mucilage content, which is a polysaccharide of growing interest in the food, cosmetic, and pharmaceutical industries. In this study, powdered mucilage was obtained from cladodes of Opuntia ficus-indica (OFI) and aloe vera (AV) leaves, and their molecular, morphological, and thermal properties were investigated and compared. Additionally, their dietary fiber content was determined. Three-dimensional molecular models were calculated for both mucilages using ab initio methods. Vibrational spectra (FTIR and Raman) revealed intramolecular interactions and functional groups that were specified with the help of theoretical ab initio and semi-empirical calculations. SEM micrographs measured at magnifications of 500× and 2000× demonstrated significantly different superficial and internal morphologies between these two mucilages. Thermal analysis using DSC/TGA demonstrated superior thermal stability for the OFI mucilage. The dietary fiber content in OFI mucilage was more than double that of AV mucilage. Our results show that both dehydrated mucilages present adequate thermal and nutritional properties to be used as functional ingredients in industrial formulations; however, OFI mucilage exhibited better physicochemical and functional characteristics than AV mucilage as a raw material.

Relationship between the index of protein modification (Kolbach index) and degradation of macromolecules in wheat malt

Kolbach index (KI) is an important index to evaluate the qualities of malt, which will affect protein molecular composition, enzyme activity, and other macromolecules degradation during wheat malting. In this paper, the relationship between wheat (Triticum aestivum L.) malts KI and the (i) characterization of albumins, globulins, gliadins, and glutenins and their hydrolysis and (ii) the enzymatic breakdown of starch and arabinoxylans during malting were studied. As malt KI values increased, all fractions of glutenins and gliadins were extensively hydrolyzed. The higher Mw globulins (36.6 to 70.8 kDa) were also increasingly degraded at higher KI values, but the concentration of smaller globulin fractions (14.9 to 35.0 kDa) had increased significantly. As for albumins, although their overall concentration had increased as KI increased, changes in the concentration of individual albumin fractions was more complex. While there were significant increases in the concentration of some new albumin proteins (43.8 and 84.4 kDa), the concentration of some albumins decreased (21.1 to 64.3 kDa), and some fractions had completely disappeared (28.8 and 64.3 kDa). Following mashing, the hydrophobicity of the worts had decreased significantly at higher KI values. At malt KI values between 39.5% and 42.7%, the enzymatic activity was at its highest, the degradation of starch was adequate and stable, and the concentration of water-soluble arabinoxylans was optimal. A KI value of about 39.5% to 42.7% was therefore considered optimal for the production of wheat malts with superior quality attributes. PRACTICAL APPLICATION: The findings from this study will be valuable to beer companies; a more precise control of the malting and brewing parameters, fundamental for the production of high-quality wheat malts and wheat beer, can be achieved.