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71.
Deux protocoles expérimentaux sur des rats Wistar mles prépubères, ont été comparés en étudiant l'influence d'une lotion d'extraits végétaux sur la synthèse de la kératine du poil. Par l'utilisation de la cystéine S-35 comme précurseur marqué on démontre un effet stimulant de la préparation essayée sur la synthèse de la kératine par les follicules pileux permettant peut-ětre secondairement une pousse plus active du poil.
Les deux protocoles expérimentaux, avec un ou plusieurs prélèvement de poil chez le měme animal, donnent des résultats comparables et significatifs. L'activité de la lotion est démontrée dès le huitième jour d'application quotidienne, et 24 heures aprés l'ingestion du précurseur marqué avec un maximum en fin de la phase catagène. 相似文献
Les deux protocoles expérimentaux, avec un ou plusieurs prélèvement de poil chez le měme animal, donnent des résultats comparables et significatifs. L'activité de la lotion est démontrée dès le huitième jour d'application quotidienne, et 24 heures aprés l'ingestion du précurseur marqué avec un maximum en fin de la phase catagène. 相似文献
72.
L I Stateva P V Venkov A A Hadjiolov L A Koleva N L Lyudskahov 《Yeast (Chichester, England)》1988,4(3):219-225
A series of prototrophic fragile strains of different ploidy (2n, 3n and 4n) has been genetically constructed on the basis of haploid srb1 containing segregants of the fragile Saccharomyces cerevisiae mutant VY 1160. The strains have been characterized by several criteria. In regard to generation time, biomass yield, and nucleic acids content of the cells, the tetraploid srb1 homozygous hybrid is indistinguishable from an industrial strain of S. cerevisiae. However, it is characterized by a higher protein content. Unlike any other laboratory or industrial strains, the original mutant and these hybrids possess an ability for lysis upon suspension in hypotonic solutions. The dependence of the percentage of lysed cells on the growth phase and concentration of osmotic stabilizer in the medium has been investigated. The quantity of proteins in the soluble and insoluble fractions obtained after lysis of these strains by osmotic shock has been determined. These hybrids can be considered as a potential industrial source of proteins for nutritional purposes. 相似文献
73.
Several experiments were carried out to confirm the allelopathic potential ofAmbrosia cumanensis H.B.K. (Compositae) in a tropical zone of Mexico. The aqueous extracts of leaves and roots inhibited growth of several species used in bioassays. The wash-water of the leaves inhibited some species and stimulated others. The aqueous solutions of soil, in reference to those collected in July, were significant in their general inhibitory action. Decomposition of leaves and roots, in pots where several species were growing, was highly inhibitory to some of the seedlings; microorganisms have a major role in this process. 相似文献
74.
Francisco?Wendel?B.?Aquino Sueli?RodriguesEmail author Ronaldo?F.?Nascimento Ant?nio?Renato?S.?Casimiro 《European Food Research and Technology》2005,221(6):739-745
In response to the increasing demand for aged distilled spirits, wood extracts have been investigated as accelerating agents
in distilled spirits. The aim of this work was to obtain and to evaluate the potential use of Amburana cearensis powder extracts as an accelerating aging agent in sugar cane distilled spirits. Wood powder was submitted to different toasting
treatments using conventional drying oven and microwave oven. Instead of using the traditional reflux extraction method, the
phenolic compounds were extracted by means of ultrasonic treatment using a 50% ethanolic solution with pH adjusted to 4.5.
The concentration of gallic acid, 5-hydroxymethylfurfural, furfural, vanillic acid, syringic acid, vanillin, coniferaldehyde,
sinapaldehyde and coumarin, determined by high performance liquid chromatography (HPLC) were used as quality parameters of
powder toasting treatment and ethanolic extraction. The use of toasted wood powder combined with ultrasonic extraction showed
higher yields when compared to the traditional solvent extraction method when obtaining wood extracts. The extraction method
presented in this work is also less time consuming. 相似文献
75.
The effect of heartwood extracts from Acacia mangium (heartrot-susceptible) and A. auriculiformis (heartrot-resistant) was examined on the growth of wood rotting fungi with in vitro assays. A. auriculiformis heartwood extracts had higher antifungal activity than A. mangium. The compounds 3,4,7,8-tetrahydroxyflavanone and teracacidin (the most abundant flavonoids in both species) showed antifungal activity. A. auriculiformis contained higher levels of these flavonoids (3.5- and 43-fold higher, respectively) than A. mangium. This suggests that higher levels of these compounds may contribute to heartrot resistance. Furthermore, both flavonoids had strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and laccase inhibition. This suggests that the antifungal mechanism of these compounds may involve inhibition of fungal growth by quenching of free radicals produced by the extracellular fungal enzyme laccase. 相似文献
76.
77.
香辛料提取物在肉品保鲜中的作用及应用 总被引:2,自引:1,他引:1
天然香辛料提取物对肉品具有抑菌防腐作用和抗氧化作用,可用于肉品保鲜。本文主要论述了香辛料提取物的提取和使用方法、对肉品的作用以及其作为保鲜剂在冷却肉和肉制品中的应用情况。 相似文献
78.
Višnja Katalinić Sonja Smole Možina Danijela Skroza Ivana Generalić Helena Abramovič Mladen Miloš Ivica Ljubenkov Saša Piskernik Ivan Pezo Petra Terpinc Mladen Boban 《Food chemistry》2010
The aim of the present study was to determine polyphenolic composition, related antioxidative and antimicrobial properties of grape skin extracts from 14 grape varieties (seven white and seven red grape) grown in Dalmatia (Croatia). The content of total phenols, flavonoids, catechins, flavanols and individual polyphenols ((+)-catechin, (−)-epicatechin, epicatechin gallate, procyanidin B1 and procyanidin B2, quercetin glucoside, resveratrol monomers, piceid and astringin) was variety dependent. Antioxidant properties were determined as DPPH radical-scavenging ability (IC50), ferric reducing/antioxidant power (FRAP), Fe2+-chelating activity (IC50), and using β-carotene bleaching assay. The high antioxidant capacity of all extracts, both red and white, has been observed and related to the relative amounts of polyphenolic compounds with good antioxidant properties. The antimicrobial activity was screened by broth microdilution test using Gram-positive (Staphylococcus aureus, Bacillus cereus) and Gram-negative bacteria (Escherichia coli O157:H7, Salmonella Infantis, Campylobacter coli). It was confirmed against all tested organisms. Minimum inhibitory concentrations (MICs), were found in the range 0.014–0.59 mg of gallic acid equivalents (GAE)/ml, with lower MICs of white cultivars, especially against Campylobacter and Salmonella. 相似文献
79.
Amlan Kumar Patra Devki Nandan Kamra Neeta Agarwal 《Journal of the science of food and agriculture》2010,90(3):511-520
BACKGROUND: An experiment was conducted to study the effects of boiling water, methanol and ethanol extracts (0, 0.25 and 0.50 mL) of seeds of Foeniculum vulgare (fennel), flower buds of Syzygium aromaticum (clove), bulbs of Allium sativum (garlic), bulbs of Allium cepa (onion) and roots of Zingiber officinalis (ginger) on rumen methanogenesis, fibrolytic enzyme activities and fermentation characteristics in vitro. RESULTS: Ethanol and methanol extracts of fennel, clove and garlic at 0.50 mL and clove at 0.25 mL inhibited (P < 0.05) methane production. Carboxymethylcellulase activity was reduced (P < 0.05) by ethanol and methanol extracts (0.50 mL) of fennel and clove (0.25 and 0.50 mL). The extracts of clove reduced (0.25 and 0.50 mL) xylanase and acetylesterase activities, and the fennel extract (0.50 mL) reduced (P < 0.05) xylanase activity. However, the extracts of garlic (0.50 mL) increased (P < 0.05) acetylesterase activity. Concentrations of volatile fatty acids were reduced (P < 0.05) by the extracts of garlic and onion. The extracts of garlic caused a decrease (P < 0.05) in acetate:propionate ratio (A:P) at 0.50 mL, whereas A:P was increased (P < 0.05) by the inclusion of 0.50 mL extracts of clove. Methanol and ethanol extracts of clove decreased (P < 0.05) in vitro organic matter degradability. Extracts (0.50 mL) of clove decreased (P < 0.05) the numbers of total protozoa, small entodiniomorphs and holotrichs, whereas extracts of onion, ginger and garlic enhanced (P < 0.05) protozoal numbers (both entodiniomorphs and holotrichs). CONCLUSION: Ethanol and methanol extracts of fennel and garlic have potential to inhibit rumen methanogenesis without adversely affecting rumen fermentation. Copyright © 2009 Society of Chemical Industry 相似文献
80.
Total Phenolic Compounds, Flavonoids, and Radical Scavenging Activity of 21 Selected Tropical Plants
ABSTRACT: Free radical scavenging activity of 21 tropical plant extracts was evaluated using 1,1-diphenyl-2-picrylhydrazyl assay (DPPH). Total phenolic compounds and flavonoids were determined using Folin–Ciocalteu and HPLC, respectively. Results of the study revealed that all the plants tested exhibited excellent antioxidant activity with IC50 in the range of 21.3 to 89.6 μg/mL. The most potent activity was demonstrated by Cosmos caudatus (21.3 μg/mL) and Piper betle (23.0 μg/mL) that are not significantly different than that of -tocopherol or BHA. L. inermis extract was found to consist of the highest concentration of phenolics, catechin, epicatechin, and naringenin. High content of quercetin, myricetin, and kaempferol were identified in Vitex negundo , Centella asiatica , and Sesbania grandiflora extracts, respectively. Luteolin and apigenin, on the other hand, were found in Premna cordifolia and Kaempferia galanga extracts. Strong correlation ( R = 0.8613) between total phenolic compounds and total flavonoids ( R = 0.8430) and that of antioxidant activity of the extracts were observed. The study revealed that phenolic, in particular flavonoids, may be the main contributors to the antioxidant activity exhibited by the plants.
Practical Application: Potent antioxidant from natural sources is of great interest to replace the use of synthetic antioxidants. In addition, some of the plants have great potential to be used in the development of functional ingredients/foods that are currently in demand for the health benefits associated with their use. 相似文献
Practical Application: Potent antioxidant from natural sources is of great interest to replace the use of synthetic antioxidants. In addition, some of the plants have great potential to be used in the development of functional ingredients/foods that are currently in demand for the health benefits associated with their use. 相似文献