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961.
Oliveira FS Canola JC Oliveira PT Pécora JD Capelli A 《Anatomia, histologia, embryologia》2006,35(5):316-318
Two newborn males, two adult males 9 and 72 months old, one newborn female and two adult females of 30 and 54 months old pacas were used. Animals were radiographed on lateral recumbency, teeth were extracted and the vestibulolingual and mesiodistal lengths were achieved at the occlusal surface, besides the longitudinal length. The lower incisors presented greater length in relation to the other ones and sinuous shape; the upper incisors, relatively smaller, are practically straight. There is no canine tooth, and after a great diastema there is one premolar and three molars in each hemiarcade. In adult pacas, the enamel of incisors presents yellowish colour, mainly in the labial surface; in the premolars and molars, the enamel is present as internal sheets disposed nearly in a parallel way and in vestibulolingual direction, through practically all the dental length, which provides several joined teeth aspect. 相似文献
962.
Amaral JS Casal S Alves MR Seabra RM Oliveira BP 《Journal of agricultural and food chemistry》2006,54(4):1329-1336
Hazelnuts from 19 cultivars collected during 3 consecutive-year crops, in 2 different geographical localities, for a total of 79 samples, were evaluated for their contents in tocopherols and tocotrienols by normal-phase high-performance liquid chromatography coupled to a series arrangement of a diode array and a fluorescence detector. Seven compounds were identified and quantified. All samples presented alpha-, beta-, gamma-, and delta- tocopherols and beta-tocotrienol; alpha- and gamma-tocotrienols were detected in some of the studied samples. alpha-Tocopherol was the major compound in all samples, ranging from 105.9 to 226.8 mg/kg of hazelnut. Considering the generality of the obtained results, an identical qualitative and quantitative pattern was found, which can define a chemical fingerprint that may be helpful in the assessment of identity and quality of hazelnut oils. Statistical analyses were carried out in order to check for differences among cultivars, year crops, and geographical localities. Although some differences were observed when different-year crops and geographical localities were considered, neither of these factors seemed to produce considerable differences in terms of tocopherol and tocotrienol contents. Some minor differences were observed among cultivars. 相似文献
963.
Vellosa JC Khalil NM Formenton VA Ximenes VF Fonseca LM Furlan M Brunetti IL Oliveira OM 《Fitoterapia》2006,77(3):243-244
Maytenus ilicifolia is an important plant with potential on cancer treatment and has been largely used in Brazil and other countries. We have evaluated the crude ethanolic extract of M. ilicifolia as a potential antioxidant source using an assay based on the bleaching of the radical monocation 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(*+)) and by HOCl scavenger capacity. Trolox and uric acid were used as positive controls. The results indicated M. ilicifolia root bark as a great source of antioxidants based on its potential as scavenger of radicals. 相似文献
964.
Viana PA de Rezende ST Marques VM Trevizano LM Passos FM Oliveira MG Bemquerer MP Oliveira JS Guimarães VM 《Journal of agricultural and food chemistry》2006,54(6):2385-2391
Raffinose oligosaccharides (RO) are the factors primarily responsible for flatulence upon ingestion of soybean-derived products. ROs are hydrolyzed by alpha-galactosidases that cleave alpha-1,6-linkages of alpha-galactoside residues. The objectives of this study were the purification and characterization of extracellular alpha-galactosidase from Debaryomyces hansenii UFV-1. The enzyme purified by gel filtration and anion exchange chromatographies presented an Mr value of 60 kDa and the N-terminal amino acid sequence YENGLNLVPQMGWN. The Km values for hydrolysis of pNP alphaGal, melibiose, stachyose, and raffinose were 0.30, 2.01, 9.66, and 16 mM, respectively. The alpha-galactosidase presented absolute specificity for galactose in the alpha-position, hydrolyzing pNPGal, stachyose, raffinose, melibiose, and polymers. The enzyme was noncompetitively inhibited by galactose (Ki = 2.7 mM) and melibiose (Ki = 1.2 mM). Enzyme treatments of soy milk for 4 h at 60 degrees C reduced the amounts of stachyose and raffinose by 100%. 相似文献
965.
Fabi JP Cordenunsi BR de Mattos Barreto GP Mercadante AZ Lajolo FM Oliveira do Nascimento JR 《Journal of agricultural and food chemistry》2007,55(15):6118-6123
Ripening affects the quality and nutritional contents of fleshy fruits, and papayas are climacteric fruits very susceptible to postharvest losses due to the fast softening caused by ethylene. This paper reports the changes in respiration, ethylene production, and pulp color and firmness, along with the contents of soluble sugars and major carotenoids, during ripening of 'Golden' papaya, an important Brazilian cultivar that has been exported to North American and European markets. The results obtained for nontreated and ethylene- or 1-MCP-treated papaya suggest that 1-MCP can decrease the quality of treated fruit and that even the use of ethylene for triggering or inducing homogeneous ripening can result in lower quality when compared to that of fruit allowed to ripe naturally. 相似文献
966.
Drinkine J Lopes P Kennedy JA Teissedre PL Saucier C 《Journal of agricultural and food chemistry》2007,55(4):1109-1116
A method was developed to determine the amount of ethylidene-bridged flavan-3-ols in wine. The method was based upon the analysis of 2,2'-ethylidenediphloroglucinol (EDP), a product formed after acid-catalyzed cleavage of wine flavan-3-ols in the presence of excess phloroglucinol. In the developed analytical method, the wine was purified and concentrated using C18 solid-phase extraction before the phloroglucinolysis reaction was carried out. This procedure was used to quantify ethylidene-bridged flavan-3-ols in wine and the molar ratio between ethylidene-bridged linkages and native interflavan linkages. The method validation showed 9.2% repeatability. The recovery of the ethylidene-bridged flavanols in wine was 90% for concentrations up to 4.5 mg.L-1 of ethylidene-bridged linkages, and it decreases to 83% above and until the concentration reached 7.6 mg.L-1. Initial results showed that the concentration of ethylidene-bridged flavan-3-ols measured in wines was very low (less than 1.3 mg.L-1) and that they represented less than 1.3% of the total interflavonoid linkages on a molar ratio. 相似文献
967.
Oliveira AS Migliolo L Aquino RO Ribeiro JK Macedo LL Andrade LB Bemquerer MP Santos EA Kiyota S Sales MP 《Journal of agricultural and food chemistry》2007,55(18):7342-7349
A trypsin inhibitor, PdKI, was purified from Pithecellobium dumosum seeds by TCA precipitation, trypsin-sepharose chromatography, and reversed-phase-HPLC. PdKI was purified 217.6-fold and recovered 4.7%. SDS-PAGE showed that PdKI is a single polypeptide chain of 18.9 kDa and 19.7 kDa by MALDI-TOF. The inhibition on trypsin was stable in the pH range 2-10 and at a temperature of 50 degrees C. The Ki values were 3.56 x 10(-8)and 7.61 x 10(-7) M with competitive and noncompetitive inhibition mechanisms for trypsin and papain, respectively. The N-terminal sequence identified with members of Kunitz-type inhibitors from the Mimosoideae and Caesalpinoideae subfamilies. PdKI was effective against digestive proteinase from Zabrotes subfasciatus, Ceratitis capitata, Plodia interpunctella, Alabama argillaceae, and Callosobruchus maculatus, with 69, 66, 44, 38, and 29% inhibition, respectively. Results support that PdKI is a member of the Kunitz inhibitor family and its insecticidal properties indicate a potent insect antifeedant. 相似文献
968.
Jacques RA Arruda EJ de Oliveira LC de Oliveira AP Dariva C de Oliveira JV Caramão EB 《Journal of agricultural and food chemistry》2007,55(18):7510-7516
The influence of agronomic variables (light intensity, age of leaves, and fertilization type) on the content of macronutrients and micronutrients (potassium, calcium, sodium, magnesium, manganese, iron, zinc, and copper) of tea leaves was assessed by acid digestion, followed by flame atomic absorption spectrometry (FAAS). The thermal behavior of mate tea leaves (Ilex paraguariensis) was also studied in this work. Samples of mate (Ilex paraguariensis) were collected in an experiment conducted under agronomic control at Erva-Mate Bar?o Commerce and Industry LTD (Brazil). The results showed that the mineral content in mate is affected by the agronomic variables investigated. In general, the content of mineral compounds analyzed is higher for younger leaves and for plants cultivated in shadow. Thermal analysis of samples indicated a similar behavior, with three typical steps of decomposition: loss of water, degradation of low-molecular weight compounds, and degradation of residual materials. 相似文献
969.
Jacques RA Krause LC Freitas Ldos S Dariva C Oliveira JV Caramão EB 《Journal of agricultural and food chemistry》2007,55(25):10081-10085
The main objective of this work is to assess the influence of two drying methods (microwave and vacuum oven) and some agronomic variables (plant fertilization conditions and sunlight intensity) on the characteristics of mate tea (Ilex paraguariensis) leaves extracts obtained from high-pressure carbon dioxide extractions performed in the temperature range from 20 to 40 degrees C and from 100 to 250 bar. Samples of mate were collected in an experiment conducted under agronomic control at Ervateira Bar?o LTDA, Brazil. Chemical distribution of the extracts was evaluated by gas chromatography coupled with a mass spectrometer detector (GC/MS). In addition to extraction variables, results showed that both sample drying methods and agronomic conditions exert a pronounced influence on the extraction yield and on the chemical distribution of the extracts. 相似文献
970.
Rocha Ribeiro SM Queiroz JH Lopes Ribeiro de Queiroz ME Campos FM Pinheiro Sant'ana HM 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):13-17
This work was carried out to investigate the pulp composition of four mango cultivars (Haden, Tommy Atkins and Ubá) at the
ripening stage in relation to three components with antioxidant potential (total phenolics, carotenoids and ascorbic acid).
Total phenolic compound content was estimated by the Folin-Ciocalteu reagent and total carotenoid content by spectrophotometry
at 450 nm. The contents of β-carotene and total vitamin C (ascorbic acid and dehydroascorbic acid) were quantified by high performance liquid chromatography.
Differences were found among the four mango cultivars in all the components analyzed. The content of phenolic compounds ranged
from 48.40 (Haden) to 208.70 mg/100 g (Ubá); total carotenoid from 1.91 (Haden) to 2.63 mg/100 g (Palmer); β-carotene from 661.27 (Palmer) to 2,220 μg/100 g (Ubá) and total ascorbic acid ranged from 9.79 (Tommy Atkins) to 77.71 mg/100 g
(Ubá). These results corroborated previous information that mangoes are a good source of antioxidants in human diet. 相似文献