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61.
Maya Sarah Isti Madinah Hasibuan Erni Misran Seri Maulina 《Molecules (Basel, Switzerland)》2022,27(19)
Optimization of pectin extraction from cocoa pod husk was carried out to examine independent variables that affect the quality of pectin obtained and determine the best conditions for the extraction process. In this study, three independent variables thought to contribute to microwave-assisted pectin extraction were used, namely, extraction time (20, 25, and 30 min), microwave power (180, 300, and 450 W), and citric acid concentration (2.5%, 5%, and 10%). Response surface methodology was applied using central composite design (CCD) to examine the effect of independent variables on the parameter measured. Among the seven parameters measured, namely, yield, temperature, moisture content, ash content, equivalent weight, methoxyl content, and galacturonic acid content, the statistical analysis test showed that the model equations that were suitable for predicting response values were temperature, moisture content, and ash content. Therefore, the optimization of conditions was only reviewed for these three parameters. Optimization results concluded that the factors that had the most significant effect on temperature, moisture content, and ash content were extraction time and microwave power. Optimal conditions for pectin extraction were at 30 min extraction time, 450 W microwave power, and 10% solvent concentration, resulting in a temperature of 104 °C, moisture content of 6%, and ash content of 8%. Other parameter values measured under these conditions were a yield of 21.10%, equivalent weight of 602.40 mg/mol, methoxyl content of 6.07%, and galacturonic acid content of 72.86%. Pectin extracted from cocoa pod husk using this method has the potential to be further applied, especially in the food and pharmaceutical industries. 相似文献
62.
Talha Bin Emran Fahadul Islam Saikat Mitra Shyamjit Paul Nikhil Nath Zidan Khan Rajib Das Deepak Chandran Rohit Sharma Clara Mariana Gonalves Lima Ahmed Abdullah Al Awadh Ibrahim Abdullah Almazni Abdulaziz Hassan Alhasaniah Raquel P. F. Guin 《Molecules (Basel, Switzerland)》2022,27(21)
Pectin is an acidic heteropolysaccharide found in the cell walls and the primary and middle lamella of land plants. To be authorized as a food additive, industrial pectins must meet strict guidelines set forth by the Food and Agricultural Organization and must contain at least 65% polygalacturonic acid to achieve the E440 level. Fruit pectin derived from oranges or apples is commonly used in the food industry to gel or thicken foods and to stabilize acid-based milk beverages. It is a naturally occurring component and can be ingested by dietary consumption of fruit and vegetables. Preventing long-term chronic diseases like diabetes and heart disease is an important role of dietary carbohydrates. Colon and breast cancer are among the diseases for which data suggest that modified pectin (MP), specifically modified citrus pectin (MCP), has beneficial effects on the development and spread of malignancies, in addition to its benefits as a soluble dietary fiber. Cellular and animal studies and human clinical trials have provided corroborating data. Although pectin has many diverse functional qualities, this review focuses on various modifications used to develop MP and its benefits for cancer prevention, bioavailability, clinical trials, and toxicity studies. This review concludes that pectin has anti-cancer characteristics that have been found to inhibit tumor development and proliferation in a wide variety of cancer cells. Nevertheless, further clinical and basic research is required to confirm the chemopreventive or therapeutic role of specific dietary carbohydrate molecules. 相似文献
63.
Pakkapong Phucharoenrak Chawanphat Muangnoi Dunyaporn Trachootham 《Molecules (Basel, Switzerland)》2022,27(3)
Green extraction is aimed at reducing energy consumption by using renewable plant sources and environmentally friendly bio-solvents. Lime (Citrus aurantifolia) is a rich source of flavonoids (e.g., hesperidin) and limonoids (e.g., limonin). Manufacturing of lime products (e.g., lime juice) yields a considerable amount of lime peel as food waste that should be comprehensively exploited. The aim of this study was to develop a green and simple extraction method to acquire the highest yield of both limonin and hesperidin from the lime peel. The study method included ethanolic-aqueous extraction and variable factors, i.e., ethanol concentrations, pH values of solvent, and extraction temperature. The response surface methodology was used to optimize extraction conditions. The concentrations of limonin and hesperidin were determined by using UHPLC-MS/MS. Results showed that the yields of limonin and hesperidin significantly depended on ethanol concentrations and extraction temperature, while pH value had the least effect. The optimal extraction condition with the highest amounts of limonin and hesperidin was 80% ethanol at pH 7, 50 °C, which yields 2.072 and 3.353 mg/g of limonin and hesperidin, respectively. This study illustrates a green extraction process using food waste, e.g., lime peel, as an energy-saving source and ethanol as a bio-solvent to achieve the highest amount of double bioactive compounds. 相似文献
64.
Gustavo Cabrera-Barjas Aleksandra Nesic Gaston Bravo-Arrepol Saddys Rodríguez-Llamazares Oscar Valds Aparna Banerjee Johanna Castao Cdric Delattre 《Molecules (Basel, Switzerland)》2021,26(24)
This study investigated the biocomposite pectin films enriched with murta (Ugni molinae T.) seed polyphenolic extract and reinforced by chitin nanofiber. The structural, morphological, mechanical, barrier, colorimetric, and antioxidant activity of films were evaluated. The obtained data clearly demonstrated that the addition of murta seed extract and the high load of chitin nanofibers (50%) provided more cohesive and dense morphology of films and improved the mechanical resistance and water vapor barrier in comparison to the control pectin film. The antioxidant activity ranged between 71% and 86%, depending on the film formulation and concentration of chitin nanofibers. The presented results highlight the potential use of chitin nanofibers and murta seed extract in the pectin matrix to be applied in functional food coatings and packaging, as a sustainable solution. 相似文献
65.
Antonino Scurria Marzia Sciortino Alessandro Presentato Claudia Lino Elena Piacenza Lorenzo Albanese Federica Zabini Francesco Meneguzzo Domenico Nuzzo Mario Pagliaro Delia Francesca Chillura Martino Rosa Alduina Giuseppe Avellone Rosaria Ciriminna 《Molecules (Basel, Switzerland)》2021,26(1)
An HS-SPME GC-MS analysis of the volatile compounds adsorbed at the outer surface of lemon and grapefruit pectins obtained via the hydrodynamic cavitation of industrial waste streams of lemon and grapefruit peels in water suggests important new findings en route to understanding the powerful and broad biological activity of these new pectic materials. In agreement with the ultralow degree of esterification of these pectins, the high amount of highly bioactive α-terpineol and terpinen-4-ol points to limonene (and linalool) decomposition catalyzed by residual citric acid in the citrus waste peel residue of the juice industrial production. 相似文献
66.
Summary: A pectin 10mer under constant pulling speed and constant force was studied using the atomistic simulations. Molecular dynamics (MD) with the Amber99 and Amber-Glycam04 forcefields were performed. The main result of the present Amber-based MD simulations is that the two plateaux of the experimental force- extension dependence for pectin can be explained by transitions between three conformational states of pectin monomer ring (first from a chair (4C1) to boat conformation and second from boat to an inverted chair (1C4) conformation). A multi-state dynamical model of single biopolymer extension under external force was elaborated and applied to extension of polymers with three-state monomers relevant to pectin. 相似文献
67.
Oligogalacturonides of different degrees of polymerization (DP) and methyl esterification (DE) were structurally analyzed by nanoESI quadrupole ion-trap mass spectrometry. The fragmentation patterns of the oligogalacturonides were compared using the program 'Virtual Expert Mass Spectrometrist' (VEMS) for structural annotation. In the analyzed oligogalacturonides of lower DP, the generation of C/Y ions, i.e. ions retaining the glycosidic oxygen, was higher than that of B/Z ions. In general, with oligogalacturonides of higher DP, the B/Z ions were generated more abundantly. Oligogalacturonides with free carboxylic acid groups underwent higher water loss compared to fully methyl-esterified oligogalacturonides under the same fragmentation conditions. Cross-ring cleavage, in which fragmentation occurs across the ring system of the galacturonate residue and signified by unique mass losses, was observed to be higher in fully methyl-esterified oligogalacturonides than in non-methyl-esterified ones. This study demonstrates the different fragmentation patterns of oligogalacturonides as influenced by the presence or absence of methyl ester groups. For a detailed analysis of unknown oligogalacturonides, cross-ring fragmentation gives more structural information than glycosidic bond cleavage. One implication of this is that more structural information is obtained when analyzing methyl-esterified oligogalacturonides than non-methyl-esterified ones in an ion-trap instrument. This is of particular importance in pectin chemistry, where mass spectrometry has become the technique of choice for structural determination. Although this study was not designed to explain the mechanisms of oligogalacturonide fragmentation, possible explanations for why non-methyl-esterified oligogalacturonides undergo more water loss than methyl-esterified ones will be postulated. In addition, the VEMS program was extended to automatically interpret and assign the fragment ions peaks generated in this study. 相似文献
68.
Oil-in-water emulsions containing 40% wt sunflower oil were prepared using ultrasound with the frequency of 30 kHz. The effect of sonication time, stabilizer concentration, NaCl, and pH of aqueous phase on the stability and particle size distribution of samples was investigated using Taguchi statistical method. The results showed that increasing sonication time decreased mean diameter of droplets and narrowed droplet size distribution curves. NaCl was found to have a positive effect on the stability of samples. More stable emulsions were prepared when using xanthan and pectin together at pH 4. 相似文献
69.
Khadidja Youce Ettoumi Yamina Zouambia Nadji Moulai-Mostefa 《Journal of Dispersion Science and Technology》2017,38(1):26-32
The present study was conducted to enhance the peel of Citrus sinensis (sweet orange) by using their essential oils (EOs) as a potential source of natural bioactive molecules. EOs were obtained by hydrodistillation and their chemical profile was determined through GC-MS analysis. O/W EO emulsions were prepared using pectin as biopolymer emulsifier at different proportions, including different amounts of ascorbic acid (0, 0.5, and 1% w/w). The effect of pectin and ascorbic acid concentrations on the stability and rheological behavior of emulsions was investigated. It was found that adding ascorbic acid to the appropriate concentration of pectin enhances the interfacial membranes surrounding the oil droplets and decreases the droplet sizes. As a result both the viscoelastic modules and the resulting viscosity of emulsions increase leading to an improvement of their stability. Antioxidant activity of orange EO emulsion in combination with ascorbic acid was found significantly higher than that without ascorbic acid, and higher than that of individual components. Overall, this study would be helpful in developing more effectives systems with promising physical and antioxidant characteristics for the preservation of foods. 相似文献
70.
流动注射-氢化物发生-原子吸收光谱法测定果胶铋 总被引：1，自引：0，他引：1
本文采用流动注射 氢化物发生 原子吸收光谱法测定了果胶铋中铋的含量 ,方法简单、快速、准确 ,考察了实验参数对测定果胶铋中铋的影响。线性范围为 0 0 0～ 4 4 0 0ng·mL- 1 ,工作曲线回归方程为A =0 0 12 +0 0 17c(c:ng·mL- 1 ) ,相关系数r=0 9995 ,检测限为 0 0 95ng·mL- 1 ,回收率在 97 3%～ 10 3 3% ,用于实际样品的分析结果满意。 相似文献