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41.
Phenolic contents,antioxidant activities and potential bioaccessibilities of industrial pomegranate nectar processing wastes 下载免费PDF全文
Ece Surek Dilara Nilufer‐Erdil 《International Journal of Food Science & Technology》2016,51(1):231-239
Antioxidant potential and bioaccessibility of co‐products from industrial pasteurised pomegranate nectar (PN) processing such as peel (PP), press cake (PC) and precipitate after clarification (PAC) in comparison with raw material (arils) and final products (CON and PN) were determined. Total phenolic (TPC), flavonoid (TFC), anthocyanin (TAC), tannin contents (TTC) and antioxidant activity (TAA) were determined besides identifying major phenolics and investigating in vitro bioaccessibility after gastrointestinal (GI) digestion. PP showed the highest values, except for TAC. Phenolics (12.7–43.0%) were found to be more stable than anthocyanins (0.6–2.1%) after in vitro GI digestion. PAC was found to be a better source for anthocyanins than CON and also showed higher phenolic bioaccessibility (28.8%) than PN (19.6%). PC and PAC possessed as much TPC, TFC, TTC and TAA levels as CON, with some exceptions. Therefore, these results indicated that not only PP but also PC and PAC should be valorised as a good source for phenolics and anthocyanins. 相似文献
42.
Effect of superfine grinding on physicochemical and antioxidant properties of pomegranate peel 下载免费PDF全文
Chen Zhong Yuangang Zu Xiuhua Zhao Yong Li Yunlong Ge Weiwei Wu Yin Zhang Yuanyuan Li Dongjie Guo 《International Journal of Food Science & Technology》2016,51(1):212-221
Pomegranate peel powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the pomegranate peel products. Fluidised bed jet milling technology was used to process superfine pomegranate peel powder. The physical–chemical properties of coarse powder A (D50 = 413.4 μm) and B (D50 = 197.1 μm), fine powder C (D50 = 142.6 μm) and D (D50 = 41.2 μm), superfine powder E (D50 = 7.68 μm) and raw material powder (RMP) (D50 = 352.2 μm) were investigated in this study. SEM images revealed the shape and surface morphology of six pomegranate peel powders. The physical determinations showed that the smaller the powder particle size was, the greater the surface area (from 0.214 to 1.597 m2 g?1) and bulk density (from 0.653 to 0.751 g mL?1) were, the smaller the angles of repose (from 51.69° to 38.74°) and slide (from 48.32° to 34.18°) were. The water holding capacity (WHC), water‐solubility index (WSI), polyphenols and flavonoids release were significantly improved as the size of pomegranate peel particle decreased. The results of FTIR and UV indicated that grinding process would not influence chemical composition of pomegranate peel. Vitamin C (VC) and butylated hydroxytoluene (BHT) were used in DPPH scavenging activity determination, and DPPH scavenging activity was A < RMP < BHT < B < C < D < E < VC. 相似文献
43.
Hyejin Yang Young-Chul Lee Kyoung-Sik Han Harjinder Singh Minseok Yoon Ji-Hae Park Chang-Won Cho Suengmok Cho 《Food chemistry》2013
Kiwifruit is one of the most popular fruits worldwide, and it has various biological properties, including antioxidant, anti-allergic, and cardiovascular protective effects. The peel of kiwifruit, which is a by-product of processing, is a good source of flavonoids; however, its bioactivity has not been widely investigated. In this study, we evaluated the hypnotic effects of green (GRPE, Actinidia deliciosa) and gold (GOPE, Actinidia chinensis) kiwifruit peel ethanol extracts and their solvent fractions, and the possible underlying mechanisms. Oral GRPE and GOPE administration (125–1000 mg/kg) produced a dose-dependent decrease in sleep latency and an increase in sleep duration in pentobarbital-treated mice. Among three different solvent fractions of GRPE and GOPE, ethyl acetate (EA) fractions had the greatest effect on sleep duration at 250 mg/kg. The total flavonoid contents of solvent fractions were proportional to sleep duration. Like diazepam (a GABAA–benzodiazepine (BZD) receptor agonist), the hypnotic effects of GRPE, GOPE, and their EA fractions were fully inhibited by flumazenil (a GABAA–BZD receptor antagonist). These results suggest that potentiation effects of GRPE and GOPE on pentobarbital-induced sleep in mice may be modulated by a GABAergic mechanism. 相似文献
44.
45.
The Improvement in Mechanical and Barrier Properties of Poly(Vinyl Alcohol)/Graphene Oxide Packaging Films 下载免费PDF全文
Vorrada Loryuenyong Charinrat Saewong Chaiyud Aranchaiya Achanai Buasri 《Packaging Technology and Science》2015,28(11):939-947
In this study, poly(vinyl alcohol) (PVA)‐graphite oxide and PVA‐graphene oxide (XGO) films were prepared by simple and environmentally friendly method. Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscope revealed the strong hydrogen‐bonding interactions between XGO and PVA matrix and the layered structure of tensile fracture surfaces of exfoliated PVA‐XGO films. These resulted in a remarkable improvement on mechanical and barrier properties of XGO/PVA nanocomposite films. The addition of 0.3 and 2.0 wt.% XGO showed an increase in tensile strength (49%) and failure stain (13–22%), in comparison with the neat PVA films. The dramatic improvement of 144% in elastic modulus was observed in PVA/2.0 wt.% XGO. Both O2 and water vapour permeability coefficients of PVA film decreased by about 76% and 21% at an XGO loading of 2.0 wt.%, respectively. Preliminary test was performed to determine the use of nanocomposite films to extend the shelf life of bananas. It was found that bananas packaged in nanocomposite films were ripened slower than those unpackaged or packaged in PVA films. These results demonstrate that such films could dramatically promote the application of PVA‐based films in the packaging industry. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
46.
比较了活性炭吸附法和改性柚子皮吸附法对废水中铅的去除能力。实验结果表明,活性炭吸附法对废水中铅的去除率为93.3%,耗时40 min;改性柚子皮吸附法对废水中铅的去除率为87.2%,耗时90 min。活性炭吸附法比改性柚子皮吸附法的耗时少,对废水中铅的去除率更高。但活性炭吸附法的处理成本比较高,利用改性后的柚子皮对重金属进行处理,可以变废为宝,具有环保和经济双重效益。 相似文献
47.
Antioxidant ability of potato (Solanum tuberosum) peel extracts to inhibit soybean oil oxidation 下载免费PDF全文
48.
橘皮精油中的主要成分D-柠檬烯具有较强的去污能力、抑菌功效以及天然芳香味。本研究以橘皮精油为有效成分,研制了一种绿色环保型洗衣液。通过单因素试验研究了洗衣液配方中AES、AEO-7的初步配比及质量分数,并采用正交试验优化了洗衣液中各组分的配比:D-柠檬烯15%,AEO-7 14%,AES 8%,乙醇8%,柠檬酸钠2%,KCl 0.25%,余量为蒸馏水。将含D-柠檬烯的洗衣液与市售LB洗衣液进行了去污效果、发泡力、pH值对比测试。结果表明,所制备的洗衣液洗涤效果优于市售LB洗衣液(去污比值大于1)。 相似文献
49.
Mst. Sorifa Akter Maruf Ahmed Jong Bang Eun 《International Journal of Food Science & Technology》2010,45(7):1464-1471
Dietary fibre components, hydration properties and antioxidant activities such as 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging, reducing power, metal chelating and 2,2′‐azino‐bis,3‐ethyl‐benzo‐thiazoline‐6‐sulphonic acid (ABTS) radical scavenging activities of persimmon peel powders using different washing treatments (tap water at 20 °C and hot water) were investigated. Peel powder obtained from hot water‐washed peels (74.95 g per 100 g) had higher dietary fibre content than tap water‐washed (65.50 g per 100 g) and unwashed (60.99 g per 100 g) peels. The higher content of total phenolic and ascorbic acid were found in peel powder obtained from unwashed peels, whereas washed peels had more β‐carotene content. The EC50 values of scavenging DPPH and ABTS radical for peel powders obtained from unwashed, tap water‐washed and hot water‐washed peels were 75.44, 142.18 and 110.17 μg mL?1 respectively and 5.31, 5.34 and 5.39 μg mL?1 respectively. Therefore, hot water washing is recommended to obtain better quality products from persimmon peel for use as a fibre supplement. 相似文献
50.