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

Exploiting the robust network structure of zein/low-acyl gellan gum nanocomplexes to create Pickering emulsion gels with favorable properties

Zein/low-acyl gellan gum (GG) composite particles (ZGPs) were fabricated to stabilize Pickering emulsions (termed "ZGPEs"). The wettability of ZGPs was manipulated simply by adjusting the concentration of GG. The effects of GG concentration, oil fraction and pH on ZGPEs were systematically evaluated by confocal laser scanning microscopy (CLSM), cryo-scanning electron microscopy (cryo-SEM), dynamic light scattering technique, stimulated emission depletion (STED) nanoscopy and rheology. The results showed that ZGPEs exhibited robust colloidal properties and distinct advantage over other previously reported zein-polysaccharide-based Pickering emulsions. CLSM, STED and cryo-SEM analyses revealed that the network structures formed by GG and ZGPs at the continuous phase and oil-water interface were the main contributors to the emulsion's characteristics. This study provides insights into the fabrication of food-grade Pickering emulsions with distinct characteristics that impart favorable properties to various foods and bioactive delivery systems.

Textural characteristics and sensory evaluation of yogurt fortified with pectin extracted from steeped hawthorn wine pomace

To comparatively investigate the applications potential of pectin from steeped hawthorn wine pomace (SHP), pectin-enriched yogurt was produced at set/stirred form using apple-sourced commercial pectin (CP) as control. The focus was mainly on the effect of pectins on the texture and stability of yogurt, as well as the analysis of appearance and taste, which were mainly characterized by texture analysis and sensory evaluation. Texture analysis indicated that the performance of SHP was better than that of CP, which could increase the gel rupture strength and rupture distance of set yogurt. SHP could also improve the firmness, denseness and viscosity of stirred yogurt. In other respects, SHP could also significantly increase the water holding capacity and sensory acceptance of both types of yogurt. The utilization of SHP for improving the quality of yogurt demonstrated its great potential in developing the sustainable applications of the by-product from steeped hawthorn wine.

Physicochemical properties and antioxidant activity of pectin from hawthorn wine pomace: A comparison of different extraction methods

In the paper, to enhance the value and utilization rate of hawthorn wine pomace waste, four kinds of pectin were gained from hawthorn wine pomace by hydrochloric acid method (HA-HP), citric acid method (CA-HP), cellulase method (E-HP) and microwave-assisted chelating agent method (MH-HP). The physical and chemical properties of extracted hawthorn pectin were analyzed, however, different extraction methods lead to different characteristics of extracted pectin samples. We found that the extracted hawthorn pectin was all low-methoxy pectin, and the highest extraction yield of 72.89% with high ash (9.20%) was obtained by the MH-HP method, while the galacturonic acid (Gal A) content was up to 72.24% after dealing with the CA-HP method which was the highest among the four samples, besides, the quality of gel formed by E-HP method was the best. What's more, the four extracted samples all reveled degrees of antioxidant activity with dose-dependent in vitro antioxidant, and it was CA-HP method had the best antioxidant activity, making this the first comprehensive research describing the extracting pectin from hawthorn wine pomace. This research also provides a base for industrial production of high-value products from low-cost raw materials.

Purification, Identification, and Characterization of an Endo-1,4-β-Xylanase from Wheat Malt

In this study, an endo-1,4-β-xylanase was purified from wheat malt following the procedures of ammonium sulfate precipitation, cation-exchange chromatography, and two-step anion-exchange chromatography. The purified endo-1,4-β-xylanase had a specific activity of 3.94 u/mg, demonstrating a weight average molecular weight (Mw) of approximately 58,000 Da. After LC-MS/MS (Liquid chromatography-tandem mass spectrometry) identification, the purified enzyme had the highest matching degree with a GH10 (Glycoside Hydrolase 10) domain-containing protein from wheat, there were 23 match peptides with a score above the threshold and the prot-cover was 45.5%. The resulting purified enzyme was used to investigate its degradation ability on high viscosity wheat-derived water-extractable arabinoxylan (WEAX). Degradation experiments confirmed that the purified enzyme was a true endo-acting enzyme, which could degrade large WEAX into smaller WEAX. The average degree of polymerization (avDP) and the viscosity of WEAX decreased with the increasing reaction time. The enzyme could degrade a small amount of WEAX into arabinoxylan-oligosaccharides (AXOS) with a degree of polymerization of 2-6, but no monosaccharide was produced. The degradation occurred rapidly in the first 3.5 h and decreased with the further prolongation of reaction time.

Effect of Dose and Timing of Burdock (Arctium lappa) Root Intake on Intestinal Microbiota of Mice

Water-soluble dietary fiber such as inulin improves the beta diversity of the intestinal microbiota of mice fed with a high-fat diet (HFD). The circadian clock is the system that regulates the internal daily rhythm, and it affects the pattern of beta diversity in mouse intestinal microbiota. Burdock (Arctium lappa) root contains a high concentration of inulin/fructan (approximately 50%) and is a very popular vegetable in Japan. Arctium lappa also contains functional substances that may affect intestinal microbiota, such as polyphenols. We compared the effects of inulin and A. lappa powder on the diversity of the intestinal microbiota of HFD-fed mice. 16S rDNA from the intestinal microbiota obtained from feces was analyzed by 16S Metagenomic Sequencing Library Preparation. It was found to have a stronger effect on microbiota than inulin alone, suggesting that inulin has an additive and/or synergic action with other molecules in A. lappa root. We examined the effects of intake timing (breakfast or dinner) of A. lappa on intestinal microbiota. The intake of A. lappa root in the evening had a stronger effect on microbiota diversity in comparison to morning intake. Therefore, it is suggested that habitual consumption of A. lappa root in the evening may aid the maintenance of healthy intestinal microbiota.

Pectic polysaccharides from purple passion fruit peel: A comprehensive study in macromolecular and conformational characterizations

A polysaccharide (PFPP) from purple passion fruit peel was optimally extracted, with the highest yield (10.05%, w/w) obtained under 35 °C extraction temperature, 240 W ultrasonic power, 65:1 mL/g liquid-to-solid ratio, 0.6% (w/v) ammonium oxalate, 30 min extraction time and pH 2.0. According to composition analyses, pectic PFPP and its fractions (PFPP-10, -15 and -20) were revealed as linear homogalacturonans interrupted by rhamnogalacturonan I in different lengths and extensities, where low esterification degrees (35.35-39.66%) were indicated via FT-IR. Furthermore, based on macromolecular models, comprehensive analyses on macromolecular and conformational characterizations of PFPP fractions were conducted quantitatively through, e.g., shape factor (1.42-1.79), Mark-Houwink-Sakurada exponent (0.55-0.74), conformational power-law exponent (0.52-0.58), fractal dimension (1.72-1.94) and persistence length (6.73-13.47 nm). Therefore, different semi-flexible coil conformations were proposed schematically, where lower molecular-weight PFPP fractions were less flexible. This could provide a molecular basis for precise re-utilizations of PFPP in food and pharmaceutical industries.

Ultrasound-Assisted Extraction of Pectin from Malus domestica ‘Fălticeni’ Apple Pomace

The use of an ultrasonic treatment for the extraction of pectin from Malus domestica ‘Fălticeni’ apple pomace, its effects on extraction yield and galacturonic acid content, and degree of esterification of the extracted pectin were investigated. The optimization of the extraction process showed that the highest yield of 9.183% pectin, with a 98.127 g/100 g galacturonic acid content and 83.202% degree of esterification, was obtained at 100% amplitude, pH of 1.8, SLR of 1:10 g/mL, and 30 min. The pectin obtained in optimal extraction conditions was compared to commercial citrus and apple pectin in terms of chemical composition (determined by FT-IR), thermal behaviour (analyzed by differential scanning calorimetry), rheological properties, and morphological structure (analyzed by scanning electron microscopy). By comparison to commercial citrus and apple pectin samples, the FT-IR analysis of pectin extracted by ultrasound treatment confirmed the high degree of esterification and showed similarity to that of apple pectin (88.526%). It was found that the thermal behaviour of the pectin obtained by ultrasound-assisted extraction was influenced by the narrower distribution of molecular weights and the orderly molecular arrangement, while the rheological properties (high viscosity, G0, and G1) of this sample were influenced by the morphological structure and the galacturonic acid content. The correlation coefficient showed a strong positive relationship between viscosity and galacturonic acid content (r = 0.992**).

Effects of pectin polydispersity on zein/pectin composite nanoparticles (ZAPs) as high internal-phase Pickering emulsion stabilizers

In the present study, the properties of two apple sourced-pectin (AP-1 and AP-2) were comparative studied, and their influence on the formation of high internal-phase Pickering emulsions (HIPPEs) was investigated. Results showed that AP-2 has lower polydispersity index (PDI = 2.51) than AP-1. Zein/AP-2 complex nanoparticles (ZAPs-2) was able to stabilize 80% oil-phase to form HIPPEs, while ZAPs-1 failed to remain stable at same oil fraction. After correlating GPC (Gel Permeation Chromatography) results of pectins with their emulsion behavior, pectin PDI was found to play an important role in HIPPEs formation. Storage experiments and rheological properties analysis showed that HIPPEs exerted excellent stability and plasticity. Besides, super-resolution microscopy (including cryo-SEM and STED nanoscopy) depicted an intuitive interface structure of HIPPEs. These findings may contribute some basis to manipulating emulsion performance by adjusting pectin properties, as well as to further understanding the behavior of ZAPs at O/W interface.

Structural characterization and rheological properties of a pectin with anti-constipation activity from the roots of Arctium lappa L

A new pectin (ALP-2) was extracted from the roots of Arctium lappa L. with the molecular weight of 1.84 × 10⁶ Da. ALP-2 was composed of rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose and arabinose. Results of NMR revealed that the dominant linkage types of ALP-2 were →4-α-GalpA-6-OMe-(1→, →2-α-Rha-(1→, →5-α-Araf-(1→ and →3,6-β-Galp-(1→. The ELISA results indicated ALP-2 was a typical pectin with HG chain and RG-I chain. The rheological experiments showed that ALP-2 fluid exhibited shear thinning behavior. The viscosity of ALP-2 was mainly affected by concentration, temperature, and pH. The ALP-2 fluid with elastic properties at high frequencies could be used as a thickener in the food industry. Moreover, ALP-2 with the dosages of 200 mg/kg and 400 mg/kg exhibited strong anti-constipation activity in vivo. ALP-2 treated groups could improve small intestinal movement rate and increase the weight of feces significantly in constipation mice. Therefore, ALP-2 could be considered as the active component for functional food or therapeutic agent in constipation therapy.