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101.
Inés González‐Hidalgo Sancho Bañón José María Ros 《International Journal of Food Science & Technology》2012,47(4):674-681
The main by‐product from the table olive canning industry is the stone with some residual olive flesh. The purpose of this study was to evaluate the composition – phenolic compounds (hydroxytyrosol, tyrosol and oleuropein) and tocopherol – and the antioxidant activity in different fractions (flesh, stone and seed) from the table olive by‐product and the whole by‐product. The highest amounts of phenolic compounds (1710.0 ± 33.8 mg kg?1) as well as the highest antioxidant activity (8226.9 ± 9.9 hydroxytyrosol equivalents mg kg?1) were obtained in the seed. The highest amounts of hydroxytyrosol (854.8 ± 66.0 mg kg?1) and tyrosol (423.6 ± 56.9 mg kg?1) were found in the whole by‐product from the pepper stuffed olives, while the stone without seed had the maximum oleuropein content (750.2 ± 85.3 mg kg?1). α‐Tocopherol values were between 79.8 ± 20.8 mg kg?1 in the seed of the olive stone and 6.2 ± 1.2 mg kg?1 in the whole by‐product from the anchovy‐stuffed olives. In light of the results obtained, it would seem possible to use table olive by‐product as a source of natural antioxidants in foods, cosmetics or pharmaceutical products, thus contributing to diminishing the environmental impact of table olive by‐product and to its revalorisation. 相似文献
102.
Huey-Chun Huang Hsiao-Fen Wang Kuang-Hway Yih Long-Zen Chang Tsong-Min Chang 《International journal of molecular sciences》2012,13(11):14679-14697
The study was aimed at investigating the antimelanogenic and antioxidant properties of essential oil when extracted from the leaves of Artemisia argyi, then analyzing the chemical composition of the essential oil. The inhibitory effect of the essential oil on melanogenesis was evaluated by a mushroom tyrosinase activity assay and B16F10 melanoma cell model. The antioxidant capacity of the essential oil was assayed by spectrophotometric analysis, and the volatile chemical composition of the essential oil was analyzed with gas chromatography-mass spectrometry (GC/MS). The results revealed that the essential oil significantly inhibits mushroom tyrosinase activity (IC50 = 19.16 mg/mL), down-regulates B16F10 intracellular tyrosinase activity and decreases the amount of melanin content in a dose-dependent pattern. Furthermore, the essential oil significantly scavenged 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline- 6-sulphonic acid) ABTS radicals, showed an apparent reduction power as compared with metal-ion chelating activities. The chemicals constituents in the essential oil are ether (23.66%), alcohols (16.72%), sesquiterpenes (15.21%), esters (11.78%), monoterpenes (11.63%), ketones (6.09%), aromatic compounds (5.01%), and account for a 90.10% analysis of its chemical composition. It is predicted that eucalyptol and the other constituents, except for alcohols, in the essential oil may contribute to its antioxidant activities. The results indicated that essential oil extracted from A. argyi leaves decreased melanin production in B16F10 cells and showed potent antioxidant activity. The essential oil can thereby be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products. 相似文献
103.
Benchmarking laboratory‐scale pomegranate vinegar against commercial wine vinegars: antioxidant activity and chemical composition
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104.
Effect of superfine grinding on physicochemical and antioxidant properties of pomegranate peel
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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
105.
Dongmei Liu Xing Chen Jichao Huang Xinghu Zhou Ming Huang Guanghong Zhou 《International Journal of Food Science & Technology》2017,52(12):2513-2521
The stability of antioxidant peptides from aged duck meat during processing and simulated gastrointestinal digestion was investigated. The antioxidant peptides preserved a high stability in the presence of diverse NaCl or upon various time heating. The antioxidant activities were strengthened by the addition of 4–8% glucose or by heating at 100 °C, whereas they were lost under alkaline conditions. During in vitro digestion, the antioxidant activities increased with pepsin treatment but then decreased following trypsin digestion. Pepsin hydrolysed peptides into short fragments and results in the increased exposure of internal hydrophobic amino acids. With further treatment by trypsin, peptides can be hydrolysed completely and more free amino acids were released, leading to the decline in surface hydrophobicity. These variations might be responsible for the change in antioxidant activity during in vitro digestion. The antioxidant peptides from aged duck with high stability can be used as functional food ingredients to improve human health. 相似文献
106.
107.
108.
Jianmei Yu Mohamed Ahmedna Ipek Goktepe 《International Journal of Food Science & Technology》2010,45(7):1337-1344
This study investigated the potential of peanut skin extract (PSE) as inhibitor of lipid oxidation in cooked and raw ground beef (GB) and as antimicrobial agent in raw GB. Results show that addition of PSE to raw GB before cooking significantly inhibited the formation of peroxides and TBARS in cooked GB during the refrigerated storage. PSE at concentration ≥0.06% was as effective as BHA/BHT at 0.02% in inhibiting lipid oxidation. PSE also inhibited the oxidation of meat pigments thereby preserving the fresh redness of treated meat when used at 0.02–0.10%. Microplate assay showed complete inhibition of test bacteria (Bacillus subtilis, Salmonella typhimurium, Staphylococcus aureus, Streptococcus faecalis and Escherichia coli) in the presence of PSE at 0.4% or higher. However, the antimicrobial effect of PSE in GB was less potent. Hence, PSE can primarily serve the dual purposes of preserving the colour of raw GB and preventing lipid oxidation in cooked products. 相似文献
109.
Effect of ultrasonic pretreatment on the antioxidant properties of porcine liver protein hydrolysates
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In this study, the effect of ultrasonic pretreatment on the antioxidant activity of porcine liver protein hydrolysates (PLPHs) was investigated. The results showed that the degree of hydrolysis (DH) and peptide contents of the PLPHs increased as the time of ultrasonication increased. The hydrolysate pretreated with ultrasonication for 60 s exhibited the highest DH and peptide contents. The hydrolysate pretreated with ultrasonication for 45 s exhibited the highest ferrous ion chelating ability and reducing power. The hydrolysate pretreated with ultrasonication for 30 s exhibited the highest 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity and the higher inhibitory activity in the linoleic acid autoxidation system. The molecular weight of peptides in the hydrolysates was less than 6.2 kDa. The results clearly demonstrated that ultrasonic pretreatment enhances the antioxidant activities of the PLPHs in a short period of time (15–30 s). 相似文献
110.
《Food Control》2015
Chinese red pepper (Zanthoxylum bungeanum Maxim.) leaf (ZML) extract contains high amounts of phenolic compounds possessing high total antioxidant capacity and hydroxyl, 1, 1-dipheny-2-picrylhydrazyl (DPPH) free radical scavenging activity. ZML extract was investigated as a natural antioxidant for the lipid stability of salted silver carp (Hypophthalmichthys molitrix) throughout salting and drying. Both dorsal and ventral muscles were examined for differences in moisture content, salt content, total lipid content, and degree of lipid oxidation. The hexanal content, Thiobarbituric acid reactive substances (TBARS) value, and lipoxygenase (LOX) activity in the ventral muscle were significantly higher than those of the dorsal muscle (p < 0.05). In the treatments with ZML extract, the hexanal content, the TBARS value, and the LOX activity were significantly lower (p < 0.05) during processing both in the dorsal and ventral muscles. The sensory qualities of processed salted fish could be improved with the amount of 0.030% extract in the dorsal muscle and 0.045% extract in the ventral muscle. These results showed that ZML extract can be a source of natural antioxidants and used as a food additive. 相似文献