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121.
Vitus Ikechukwu Obi Juan Jose Barriuso Yolanda Gogorcena 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(3):781-790
This investigation examines the effects of pH and titratable acidity on the growth and developments of a strain of Monilinia laxa (Aderhold & Ruhland) at seven different pH levels in Potato Dextrose Agar media and on peach fruit from formation to commercial maturity. The fungi growth was obtained by daily measurement of mycelia on the pH amended Potato Dextrose Agar. The sporulation performance was determined after 30 days of culture incubation. Fruits were inoculated with M. laxa, from fruit set to maturity, on weekly basis for brown rot susceptibility. The pathogen development, in vitro, was affected, by the pH (2.4–11.52) amended nutrient media. M. laxa exhibited variation in its growth and sporulation capacities on the seven pH amended PDA, preferring relatively moderate acidic conditions for optimum performance. In the in vitro analysis, there was mycelia growth at pH 2.40 to 8.84, while pH 11.52 did not support any mycelia growth. There was a continuous and stable increase in weight of fruit as it developed whereas the fruit size increased, then decreased and finally increased as the fruit develops. The acidity dynamics exhibited a non-sinusoidal waveform through the growth and development of the fruit. In all these characteristic variations, M. laxa did not develop infection or shown any brown rot incidence in the fruit until the period of commercial maturity. 相似文献
122.
123.
Yolanda T. Garcia Madan Mohan Dey Sheryl Ma M. Navarez 《Aquaculture Economics & Management (Blackwell Science)》2013,17(1-2):141-168
ABSTRACT This paper sought to establish the fish consumption pattern of Filipino households and estimate the price and income elasticities of fish demand by species, as well as by income groups, i.e., low, middle, and high income. The study used the countrywide Family Income and Expenditure Survey (FIES) for year 2000 of the National Statistics Office, which includes over 39,000 households. A three-stage budgeting framework was used in the analysis, which estimated food and fish expenditure functions in the first and second stages, respectively. In the third stage, a system of demand equations for fish by species was estimated using a quadratic almost ideal demand system (QUAIDS) model. Parameter estimates of the model were corrected through the Heckman procedure to remove the possible bias brought about by zero consumption of certain fish species resulting from nonpreference or infrequent purchases. Results showed that estimated price and income elasticities of demand varied substantially across fish type and across income groups. All 11 fish types included in the study were found to have positive income elasticity for all income levels. Hence, fish in general can be considered normal goods, including processed fish. However, the high-priced fish types generated elasticity values greater than one, which rendered them as luxury food fish. Own-price elasticity, on the other hand, was found to be elastic in most species with values increasing as consumers climbed up the income ladder. This observation, however, was not true in the case of milkfish and tilapia (two most popular species in the country) where price responsiveness of demand was found to be higher among the lower-income groups. 相似文献
124.
Mario Sanz-Penella J Laparra JM Sanz Y Haros M 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):50-56
The objective of the present study was to evaluate the effect of the bread supplemented with whole amaranth flour (0, 20 and
40%) on iron bioavailability using Caco-2 cells model. The phytate and lower myo-inositol phosphates content in in vitro bread digests were measured by high pressure liquid chromatography. The breads made with amaranth showed significant increase
of soluble phytates levels (up to 1.20 μmol/g in dry matter for the 40% of substitution) in comparison with controls, which have not detectable values. A negative
correlation among phytate and Fe availability was found when increased levels of amaranth. Ferritin concentration was found
2.7- and 2.0-fold higher (P < 0.05) in cultures exposed to 20% and 40% of amaranth formulated bread samples, respectively, compared to control bread.
The soluble phytate/Fe molar ratio explained the whole amaranth flour-mediated inhibitory effect associated to the limitation
of available Fe; however, the use up to 20% of amaranth in bread formulation appears as a promising strategy to improve the
nutritional value of bread, as indicated by the ferritin concentrations quantified in cell cultures. Higher proportion of
amaranth flour increased Fe concentration although there was not detected any increase in Fe uptake. 相似文献
125.
Fernando Alferez Yolanda Lluch Jacqueline K. Burns 《Postharvest Biology and Technology》2008,49(1):69-76
The role of phospholipase A2 (PLA2) activity in development of postharvest peel pitting in mature ‘Fallglo’ tangerines [Bower citrus hybrid (Citrus reticulata Blanco × C. reticulata Blanco × C. paradisi Macf.) × Temple (C. reticulata Blanco × Citrus sinensis L.)] and ‘Navel’ oranges (Citrus sinensis L. Osbeck) was investigated. Changes in RH from 30% to 90% followed by fruit waxing increased electrolyte leakage and PLA2 activity in flavedo, and induced pitting. Treatment with an aqueous dip of aristolochic acid (AT), a specific inhibitor of secretory phospholipase A2 (sPLA2) activity, immediately before transfer from 30% to 90% RH storage, markedly reduced peel pitting symptoms. Five genes encoding various phospholipase As isolated from citrus (three patatin-like and two sPLA2-like sequences) differentially accumulated in healthy areas, areas with developing lesions and necrotic lesions of disordered fruit. Other PLA2, phospholipase C, and phospholipase D inhibitors also reduced peel pitting; however, PLA2 inhibitors were the most effective in preventing the disorder. In addition, phospholipase inhibitors promoted fruit decay, suggesting that innate resistance is impacted by phospholipase action. Together, the results provide evidence for involvement of phospholipase activity in development of postharvest peel pitting symptoms in citrus fruit. 相似文献
126.
Pedrero Z Madrid Y Hartikainen H Cámara C 《Journal of agricultural and food chemistry》2008,56(1):266-271
The protective effect of selenium against the cadmium-induced oxidative effect in broccoli ( Brassica oleracea) plants was studied. Plants grown in hydroponic culture were supplied with selenium [as Se(IV)] and cadmium [as Cd(II)], individually or simultaneously. Cadmium accumulation in roots was noticeably higher than in the aerial parts of the plants, and this effect was even more acute when selenium was simultaneously added. Cadmium phytotoxicity was evidenced by an increase in the malondialdehyde (MDA) concentration in the roots and a decrease of photosynthetic pigment and tocopherol concentration in the aerial parts of the plant. The simultaneous addition of selenium alleviated cadmium-induced stress in the roots after 40 days of exposition. In the leaves, a more remarkable decrease of tocopherol and chlorophyll concentration was observed in the cadmium-enriched plants after 10 days of exposure. The results provided evidence that selenium supplementation helps the plant to minimize the cadmium oxidant effect. Tocopherol concentration in broccoli fruit of cadmium-supplied plants was not affected in comparison to control. However, the proportion of alpha-tocopherol increases with the addition of selenium. This response is important not only for the protective effect against oxidative damage in the plant but also in terms of human nutrition. 相似文献
127.
Pedro J. Ginel Rosario Lucena Yolanda Millán Sonia González‐Medina Silvia Guil José García‐Monterde Antonio Espinosa de los Monteros Juana Martín de las Mulas 《Veterinary dermatology》2010,21(3):297-302
Sebaceous gland oestrogen α (ERα) and progesterone (PR) receptor expression was examined immunohistochemically in 26 and 32 dogs respectively with sebaceous gland hyperplasia/adenomas, epitheliomas and carcinomas, and in the glands of 10 healthy controls. The mean percentage of ERα positive nuclei in control sebaceous glands was 21.31% compared with 11.5% in hyperplasia/adenoma‐type lesions, although these values were not statistically different. In sebaceous gland epitheliomas and carcinomas, positive basal cells represented 7.86% and 3.53% of neoplastic cells respectively and these mean percentages were significantly lower in epitheliomas (P < 0.024) and carcinomas (P < 0.015) than in controls. The mean percentage of PR‐positive nuclei in control sebaceous glands was 23.96%, similar to the 22.07% found in hyperplasia/adenoma‐type lesions. In sebaceous gland epitheliomas and carcinomas, positive cells were scarce and represented 13.5% and 4.06% of neoplastic cells respectively. Differences in the percentage of positive cells between normal and pathological glands reached statistical significance for carcinomas (P < 0.043). In the control group there was greater PR (P < 0.001) and ERα expression (P < 0.014) in sebaceous glands in female dogs. The PR and ERα immunoreactivity in each category of neoplastic lesions could not be analysed because sample size was too small but when all the sebaceous gland tumours were grouped and analysed, no sex difference was found. The results suggest that oestrogen and progesterone receptor expression is reduced in some canine sebaceous gland tumours. These changes may represent a contributing factor for tumour growth or simply be a consequence of tumour progression. 相似文献
128.
Measurement of porcine C-reactive protein (CRP) in serum is an important tool for monitoring health and welfare in pigs. In this study, an immunoturbidimetric method from Olympus System Reagent (OSR 6147) used to measure human CRP in serum that employ a human traceable calibrator has been evaluated in porcine serum samples. Intra- and inter-assay imprecision were lower than that obtained with the porcine-specific commercially available ELISA. The expected difference in serum CRP between healthy and non-healthy pigs was detected. CRP values measured by the immunoturbidimetric method showed a good correlation with those obtained by ELISA, although differences in absolute CRP values were observed. When an in-house porcine standard was used a better agreement was obtained. In conclusion, the immunoturbidimetric method of Olympus can be used with porcine samples. The easier use of this method should facilitate the implementation of CRP serum determination for diagnostic and prognostic purposes in swine medicine. The results emphasize the need to establish species-specific standard and methods to decrease inter-laboratory discrepancies. 相似文献
129.
Yolanda J. Brady Ernesto Lassodela Vega 《Journal of the World Aquaculture Society》1992,23(3):228-231
Seratia marcescens was used as an indicator to determine if different concentrations of bacteria in water relate to concentrations in the hemolymph of Macrobrachium rosenbergii . Prawns were exposed to high (105 to 106 cells/ml), low (103 to 104 cells/ml) and control (no S. marcescens ) treatments with S. marcescens inoculated in aquaria water. S. marcescens ranged from 10 to 9.9 ± 103 cells/ml from the high concentration group; a single isolate and zero S. marcescens were recovered from the low and control groups, respectively. 相似文献
130.
Ibarra F Vera Y Quiroz H Cantó J Castillo R Hernández A Ochoa P 《Veterinary parasitology》2004,120(1-2):65-74
The aim of the present study was to determine the effective dose of an experimental fasciolicide called compound alpha or 5-chloro-2-methylthio-6-(1-napthyloxy)1H-benzimidazole in experimentally and naturally infected cattle. In the first experiment, 24 fluke-free heifers were each infected with 800 metacercariae of Fasciola hepatica and re-infected on day 45 with other 600 cysts per animal. On day 75, when the animals had 4- and 10-week-old flukes respectively, they were divided into four groups (G) of six animals each according to fluke egg counts. Groups 1-3 received compound alpha at 10, 12 and 14 mg/kg/p.o., respectively. G4 remained as an untreated control. Twenty days after treatment, the animals were sacrificed for the recovery of flukes. Efficacy was assessed as a percentage of egg or fluke reduction relative to the untreated control. In the second experiment (naturally infected cattle), 24-year-old steers positive to F. hepatica eggs were blocked into four groups of five animals each. Groups 1-3 received compound alpha at 10, 12 and 14 mg/kg/p.o., respectively. Group 4 served as a non-treated control. All procedures to determine efficacy were carried out as mentioned in the first experiment. The results in the first study showed a percentage on egg reduction of 97.3, 100 and 100 and overall fluke reduction of 94.3, 100 and 100 for Groups 1-3, respectively. In the second study, the percentage of egg reduction was of 87.5, 99.1 and 100 and overall efficacy regarding fluke reduction was of 84.2, 99.6, and 100 for Groups 1-3, respectively. It is concluded that the effective dose selected for compound alpha was of 12 mg/kg/p.o. in cattle having an induced or natural F. hepatica infection. 相似文献