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Effects of extraction pH, temperature, and time on yield and quality of pectin from sunflower heads (Interstate cultivar) were investigated. The low-methoxyl pectin was extracted, using 0.75% sodium hexametaphosphate at pH 3, 4, and 5 and at 75, 85, and 95°for 20, 40, and 60 min, respectively. Yield, molecular mass, and firmness of jellies of the pectins were determined. Three-way statistical analysis on yield, molecular mass and gel firmness showed strong interactions among pH, temperature and time. Highest yields were obtained at pH 5, 95°for 20 min and pH 4, 85°for 40 min. Pectin extracted for 40 min at pH 3 and 4 and at 85°and 75°C, respectively, had the highest molecular mass. Gel firmness of sunflower pectin prepared at pH 5.4 was higher than that of a commercial citrus pectin. 相似文献
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Ice recrystallization rates in simple aqueous solutions comprising fructose and a hydrocolloid stabilizer were measured. The stabilizers were an enzyme-modified guar and a non-gelling high methoxy pectin. The stabilizer concentration dependence of the recrystallization rates for both materials was similar in that increasing the concentration resulted in decreasing rates until a point is reached where further addition had no additional effect. That recrystallization rates were reduced by both gelling and non-gelling stabilizers was strongly suggestive that gelation was not a requirement for recrystallization inhibition and another more specific mechanism applies, for example a weak interfacial effect such as adsorption or blocking. This behavior was also seen with locust bean gum and guar and provided further empirical evidence to support the hypothesis that stabilizers adsorb to ice crystal surfaces. 相似文献
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Identification and fermentation optimization of protopectinase-overproducing strain Aspergillus niger CD-01 for pectin production 总被引:1,自引:1,他引:0
In order to solve the citrus peel resource waste problem and minimize the drawbacks of chemical extraction of pectin, a protopectinase-overproducing
strain CD-01 for pectin production was isolated from a pit soil dumped with perished orange in Changde City, Hunan Province
of China. The strain CD-01 had the same morphology and 28S rRNA gene sequence (FJ184995) as that of Aspergillus niger (ATCC 64028). It was thus identified and named as Aspergillus niger CD-01. The fermentation condition was optimized based on L9(34) orthogonal experimental design and the variances analyses. The results show that the optimal condition for producing pectin
is as follows: time 36 h, temperature 35 °C, pH 5, and urea as the nitrogen source. Under this condition, the pectin yield
can reach up to 24.5%. This shows a great potential of Aspergillus niger CD-01 in pectin extraction from citrus.
Foundation item: Projects(50621063, 50674101) supported by the National Natural Science Foundation of China 相似文献
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Soojeong Choi Jihoon Jeon Yunsu Bae Yongsoon Hwang Seung-Woo Cho 《Advanced functional materials》2023,33(44):2303043
Oral disease is one of the most common conditions worldwide, negatively affecting general health, reducing the quality of life, and often developing into systemic illness. However, the design of therapeutic agents for oral diseases is challenging due to various unique features of the oral cavity, including its wet and dynamic environment and curved shape. Herein, the development of highly biocompatible mucoadhesive functional hydrogels for oral applications is reported, generated by introducing bio-inspired phenolic moieties into a pectin polymer. Pyrogallol-functionalized pectin (Pec-PG) can be crosslinked in situ via autoxidation without chemical agents and readily fabricated as various formulations. Sprayable Pec-PG hydrogel exhibits strong mucoadhesion and outstanding hydration ability ex vivo and in vivo, thus displaying significant potential as a novel saliva substitute for dry mouth. The authors further show that topical application of mucoadhesive Pec-PG patches pre-loaded with corticosteroid significantly promotes the repair of diabetic oral ulcer tissue via prolonged drug release, free radical scavenging, and physical barrier effects. Moreover, similar applications for oral ulcer treatment using a pectin hydrogel modified with catechol (Pec-CA), another phenolic moiety are demonstrated. Together, these findings suggest that mucoadhesive phenolic pectin derivatives can provide highly biocompatible, convenient, and effective hydrogel platforms for treating oral diseases. 相似文献
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