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1.
Ellagic acid, vitamin C, and total phenolic contents and radical scavenging capacity affected by freezing and frozen storage in raspberry fruit 总被引:9,自引:0,他引:9
The ellagic acid, total phenolic, and vitamin C contents in four raspberry cultivars (Heritage, Autumn Bliss, Rubi, and Zeva) grown in Spain were detected and quantified by HPLC in fresh, just frozen, and stored fruits at -20 degrees C for a one year period. Ellagic acid [207-244 mg kg(-)(1) of fresh weight (fw)], total phenolic (137-1776 mg kg(-)(1) of fw), and vitamin C (221-312 mg kg(-)(1) of fw) contents in raw material were higher in the late cultivars Zeva and Rubi than in the early cultivars Autumn Bliss and Heritage. The freezing process slightly affected the values of extracted ellagic acid, total phenolic, and vitamin C content. At the end of long-term frozen storage (12 months), no significant change of total phenolic content extracted was observed, but significant decreases of 14-21% in ellagic acid and of 33-55% in vitamin C were quantified. Free radical scavenging capacity measured as antiradical efficiency (AE) depends on the seasonal period of harvest. Late cultivars, Rubi (6.1 x 10(-)(4)) and Zeva (10.17 x 10(-)(4)), showed higher AE than early cultivars, Heritage (4.02 x 10(-)(4)) and Autumn Bliss (4.36 x 10(-)(4)). The freezing process produced a decrease of AE values in the four cultivars ranging between 4 and 26%. During the frozen storage, the AE values reached after the freezing process remained unchanged. 相似文献
2.
A partial characterization of polyphenol oxidase (PPO) activity in raspberry fruits is described. Two early cultivars harvested in May/June (Heritage and Autumm Bliss) and two late cultivars harvested in October-November (Ceva and Rubi) were analyzed for PPO activity. Stable and highly active PPO extracts were obtained using insoluble poly(vinylpyrrolidone) (PVP) and Triton X-100 in sodium phosphate, pH 7.0 buffer. Polyacrylamide gel electrophoresis of raspberry extracts under nondenaturing conditions resolved in one band (R(f)()(1) = 0.25). Raspberry PPO activity has pH optima of 8.0 and 5.5, both with catechol (0.1 M). Maximum activity was with D-catechin (catecholase activity), followed by p-coumaric acid (cresolase activity). Heritage raspberry also showed PPO activity toward 4-methylcatechol. Ceva and Autumm Bliss raspberries showed the higher PPO activity using catechol as substrate. 相似文献
3.
Ortiz J Ruiz de Ybañez MR Abaigar T Goyena M Espeso G Cano M Alonso F 《The Veterinary record》2001,149(1):12-15
Seven different methods of administering ivermectin to gazelles were compared: subcutaneous injection, direct oral administration, administration in individual feeds, administration in a herd feed, direct oral administration of a second ivermectin formulation, administration in individual water supplies, and administration in the herd's water supply. The first five treatments were effective, as monitored by faecal egg count reduction tests, and administration in individual feeds or in a herd feed avoided the need to capture the animals, with the attendant risk of mortality. Of the factors associated with the recipients (species, sex, age and inbreeding coefficient) age was the only significant factor for the efficacy of the treatment. Oral or subcutaneous, individual or collective, and direct or indirect administrations were equally satisfactory for the treatment of all the parasite groups studied. Only when parasitic problems were due to Nematodirus species did direct administration to individual animals appear to be preferable. 相似文献
4.
Nine heifers were intravaginally challenged with 9.3x10(6) Tritrichomonas suis reference strains. Vaginal mucus and serum samples were collected weekly 4 weeks post-inoculation. Vaginal mucus was cultured for T. suis and sera was tested by ELISA against whole cell antigens for T. suis and Tritrichomonas foetus. All vaginal mucus cultures were T. suis-negative during the experiment. ELISA values for both antigens were similar and differences were not significant (P>0.05). Positive control serum samples from one heifer vaccinated against T. foetus showed anti-T. suis ELISA values. We concluded that T. suis intravaginal inoculation induced a low level of serum immune response in heifers measured by ELISA and both protozoa probably share a common antigen. However, under the experimental conditions of this trial, colonization of the heifers' genital tract was not possible in any of the nine animals. 相似文献
5.
A method to determine imazalil (allyl 1 -(2, 4-dichlorophenyl)-2-imidazol- 1-ylethyl ether) on apples using high performance liquid chromatography is described. After harvest, fruits were immersed in an aqueous suspension (1 g litre-1) and cold stored (0-2°C) at 85-90% r.h. Samples were taken monthly and imazalil was determined in the peel, outer pulp, inner pulp and on whole fruit. Residues were 3.8-4.9 mg imazalil kg-1 and decreased during storage. Most imazalil was found on the peel and amounts in the pulp decreased toward the core. 相似文献
6.
Retracted: Effect of Post‐Thaw Storage Time on Motility and Fertility of Cryopreserved Beluga Sturgeon (Huso huso) Sperm
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The aim of this study was to test the influence of post ‐ thaw storage time on the duration of sperm motility, percentage of motile sperm, and fertilization and hatching rates of fresh sperm and sperm stored for 0, 30 and 60 min at 4°C post‐thawing. After being frozen in liquid nitrogen and then thawed, the percentage of motile sperm and duration of motility were not affected by 30 min of storage at 4°C, whereas a significant decline in these parameters was observed after 60 min of storage. Similarly, fertilization and hatching rates were significantly affected within 60 min of storage at 4°C, and the fertility of frozen‐thawed sperm was significantly lower than that of fresh sperm. We conclude that cryopreserved sperm of beluga sturgeon could be stored for 30 min without the loss of sperm quality. This described procedure for beluga sturgeon cryopreservation is reliable and efficient and therefore can be recommended for hatchery practice after scaling up this technique. 相似文献
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Two cases of Rhodococcus equl infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equl until proven otherwise. 相似文献
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