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排序方式: 共有195条查询结果,搜索用时 15 毫秒
1.
Improved production of butyrate (up to 19 g/l) from whey by Clostridium butyricum was achieved by adding either yeast extract (5 g/l) or biotin (50 g/l). Hydrolysed lactose and proteolysed whey were less effective even with added biotin.The authors are with the Department of Biochemical Technology, Faculty of Chemical Technology, Slovak Technical University, Radlinského 9, Bratislava 812 37, Slovakia  相似文献   
2.
This study was performed to compare the bioavailability of two organic zinc compounds, a zinc glycinate complex and a zinc amino acid chelate with that of zinc sulphate in growing pigs fed a basal diet composed mainly of wheat, barley and soybean meal. The experiment included 96 pigs with an average body weight of 8 kg, allotted to ten groups of nine to ten pigs each. The first group received the basal diet, containing 42 mg of native zinc per kg, without zinc supplementation over a period of five weeks. The other nine groups received the basal diet supplemented with 15, 30 or 50 mg of zinc/kg as zinc sulphate, zinc glycinate or the zinc amino acid chelate. Pigs fed the unsupplemented diet had a lower growth performance (body weight gain, feed conversion ratio) than the other nine groups. Supplementation of 15 mg zinc/kg diet (irrespective of zinc form) was sufficient to yield optimum growth performance. Plasma zinc concentration and activity of alkaline phosphatase were rising with increasing zinc supplementation levels up toa maximum reached at a supplementary level of 30 or 50 mg/kg diet for activity of alkaline phosphatase and plasma zinc concentration, respectively. The response of those parameters to zinc supplementation did, however, not differ between thethree zinc compounds considered. The apparent digestibility of zinc from the diet was also not different for the three zinc compounds. In conclusion, these findings show that the bioavailability of the two organic zinc compounds did not differ from that of zinc sulphate in growing pigs fed a diet with wheat, barley and soybean meal as major components.  相似文献   
3.
ABSTRACT

This study was conducted to assess the effect of feeding high-surface ZnO instead of common ZnO on the performance, rumen fermentation, blood minerals, leukocytes and antioxidant capacity of pre- and post-weaning calves. Thirty male suckling Holstein calves were allotted to one of three experimental groups (10 replicates) in a completely randomised design. Calves received: (1) a low Zn diet without Zn supplementation (control diet), (2) a high Zn diet containing 50 mg supplementary Zn/kg dry matter (DM) as common ZnO or (3) a high Zn diet containing 50 mg supplementary Zn/kg DM as high-surface ZnO (nano-ZnO). The control diet contained a native Zn content of 35.5, 34.7 or 33.7 mg/kg DM for the age periods of 7 to 30, 31 to 70 and 71 to 100 d, respectively. Supplementation of the diet with Zn did not change the dry matter intake (DMI) of calves during d 7 to 30 but increased the ADG in this period (p < 0.05). During age periods of 31 to 70 and 71 to 100 d, DMI and ADG of the Zn supplemented calves were higher (p < 0.05) than the control animals. The nutrient digestibility and the concentration of rumen volatile fatty acids were positively affected (p < 0.05) and the rumen ammonia-N concentration decreased (p < 0.05) by dietary Zn supplementation. Furthermore, the incidence of diarrhoea and pneumonia was lower in calves receiving the Zn supplemented diets. Irrespective of ZnO source, the blood total antioxidant capacity, leukocyte and haematocrit levels significantly increased (p < 0.05) with the ZnO supplemented diets. The post-weaning DMI, nutrient digestibility and blood haematocrit levels were higher in calves receiving high-surface ZnO, compared to those supplemented with common ZnO. With inclusion of the Zn sources in pre- and post-weaning diets, the blood Zn concentration increased (p < 0.05), but the blood Cu, Fe, Ca, P and Mg levels remained unchanged. Regardless of source, dietary supplementation of young calves with ZnO improved the performance and decreased rumen ammonia-N and the incidence of diseases. Moreover, high-surface ZnO had advantages over common ZnO in increasing the post-weaning feed intake, digestibility and blood Zn concentration.  相似文献   
4.
This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).  相似文献   
5.
This review focuses on four new product categories of food supplements: pre-workout, fat burner/thermogenic, brain/cognitive booster, and hormone/testosterone booster. Many food supplements have been shown to be contaminated with unauthorized substances. In some cases, the ingredients in the new categories of dietary supplements were medicinal products or new synthetic compounds added without performing clinical trials. Some of the new ingredients in dietary supplements are plant materials that are registered in the pharmacopoeia as herbal medicines. In other cases, dietary supplements may contain plant materials that have no history of human use and are often used as materials to ‘camouflage’ stimulants. In the European Union, new ingredients of dietary supplements, according to European Food Safety Authority or unauthorized novel food. Furthermore, selected ingredients in dietary supplements may be prohibited in sports and are recognized as doping agents by World Anti-Doping Agency.  相似文献   
6.
The North American Actaea racemosa L. (syn. Cimicifuga racemosa (L.) Nutt., commonly known as black cohosh), considered to be a more “natural” alternative to conventional therapies, is used to relieve menopausal symptoms. The high demand for plant material has led to problems with substitution/adulteration of raw material of wholesale origin. The authenticity of the starting material is crucial for the herbal product’s efficacy and safety, and tests on identity and substitution are integral parts of cGMP guidelines. Consequently, there is a need for economical and easy-applicable test procedures. The aim of this study is to reveal the capability of the well-established UV spectroscopy coupled with a multivariate classification procedure to serve as a tool for the identification of A. racemosa. We built a classification model applying linear discriminant analysis (LDA) to distinguish between A. racemosa and its common substitutes. The model showed a high level of accuracy predicting 100% of the samples correctly. Our results indicate that UV spectroscopy shows potential for the development of possible additional authentication methods for this herbal starting material.  相似文献   
7.
The role of nutrition in mental health is becoming increasingly acknowledged. Along with dietary intake, nutrition can also be obtained from “nutrient supplements”, such as polyunsaturated fatty acids (PUFAs), vitamins, minerals, antioxidants, amino acids and pre/probiotic supplements. Recently, a large number of meta‐analyses have emerged examining nutrient supplements in the treatment of mental disorders. To produce a meta‐review of this top‐tier evidence, we identified, synthesized and appraised all meta‐analyses of randomized controlled trials (RCTs) reporting on the efficacy and safety of nutrient supplements in common and severe mental disorders. Our systematic search identified 33 meta‐analyses of placebo‐controlled RCTs, with primary analyses including outcome data from 10,951 individuals. The strongest evidence was found for PUFAs (particularly as eicosapentaenoic acid) as an adjunctive treatment for depression. More nascent evidence suggested that PUFAs may also be beneficial for attention‐deficit/hyperactivity disorder, whereas there was no evidence for schizophrenia. Folate‐based supplements were widely researched as adjunctive treatments for depression and schizophrenia, with positive effects from RCTs of high‐dose methylfolate in major depressive disorder. There was emergent evidence for N‐acetylcysteine as a useful adjunctive treatment in mood disorders and schizophrenia. All nutrient supplements had good safety profiles, with no evidence of serious adverse effects or contraindications with psychiatric medications. In conclusion, clinicians should be informed of the nutrient supplements with established efficacy for certain conditions (such as eicosapentaenoic acid in depression), but also made aware of those currently lacking evidentiary support. Future research should aim to determine which individuals may benefit most from evidence‐based supplements, to further elucidate the underlying mechanisms.  相似文献   
8.
Propolis is a plant-based sticky substance that is produced by honeybees. It has been used traditionally by ancient civilizations as a folk medicine, and is known to have many pharmaceutical properties including antioxidant, antibacterial, antifungal, anti-inflammatory, antiviral, and antitumour effects. Worldwide, researchers are still studying the complex composition of propolis to unveil its biological potential, and especially its antimicrobial activity against a variety of multidrug-resistant microorganisms. This review explores scientific reports published during the last decade on the characterization of different types of propolis, and evaluates their antimicrobial activities against Staphylococcus aureus and Candida albicans. Propolis can be divided into different types depending on their chemical composition and physical properties associated with geographic origin and plant sources. Flavonoids, phenols, diterpenes, and aliphatic compounds are the main chemicals that characterize the different types of propolis (Poplar, Brazilian, and Mediterranean), and are responsible for their antimicrobial activity. The extracts of most types of propolis showed greater antibacterial activity against Gram-positive bacteria: particularly on S. aureus, as well as on C. albicans, as compared to Gram-negative pathogens. Propolis acts either by directly interacting with the microbial cells or by stimulating the immune system of the host cells. Some studies have suggested that structural damage to the microorganisms is a possible mechanism by which propolis exhibits its antimicrobial activity. However, the mechanism of action of propolis is still unclear, due to the synergistic interaction of the ingredients of propolis, and this natural substance has multi-target activity in the cell. The broad-spectrum biological potentials of propolis present it as an ideal candidate for the development of new, potent, and cost-effective antimicrobial agents.  相似文献   
9.
This work aims to enhance the flavor of functional cucumber juice using herbal extracts of peppermint, basil, lavender, and lemongrass ethanolic extracts and extend its lifetime by controlling the chemical and microbial fluctuations. Cucumber juices were processed as; non-supplemented (J-Con), J-PME, J-BE, J-LE, and J-LEE supplemented with peppermint, basil, lavender, and lemongrass ethanolic extracts, respectively. Peppermint extract was significantly scavenged 88% of DPPH radicals and inhibited the growth of tested gram-positive, gram-negative bacteria and fungi followed by the lemongrass extract. The antioxidant activity of cucumber juices increased due to polyphenols and aroma compounds in the added extracts. However, the antioxidant content was decreased after two months of storage at 4 °C, due to the decrease in polyphenols. The flavor compounds were determined using GC mass, wherein hydrocarbons, acids, alcohols, and carbonyl compounds were the main aroma contents in cucumber juices, and their contents decreased with storage time. Peppermint and lemongrass extracts were significantly (p ≤ 0.05) increased the whiteness of J-PME, and J-LEE, respectively. The highest score of flavor and taste was observed in J-PME that scored 8.3 based on panelists'' reports followed by J-LEE. The PME was significantly maintained 91% of the odor and color of J-PME as compared to other juices.  相似文献   
10.
BACKGROUND: In April of 2003, The Micronutrient Initiative, in collaboration with several other organizations, convened a group of knowledgeable scientists and policy experts to discuss ways to accelerate the global pace at which countries implement effective and sustainable programs to prevent folic acid-preventable birth defects and other folate-deficiency diseases. Programs implemented to date by fewer than 40 countries have prevented only 10% of the estimated 240,000 annual cases of folic acid-preventable spina bifida and anencephaly. METHODS: Participants in this meeting summarized and presented scientific evidence showing that increased consumption of synthetic folic acid prevents a large proportion of spina bifida and anencephaly cases. They also reviewed related guidance and endorsement issued by national professional societies and advisory bodies as well as policies and programs implemented by some countries that have already demonstrated successful results in terms of reduced rates of neural tube defects and improved folate nutrition. CONCLUSIONS: The group formulated and discussed recommendations and strategies for increasing the pace of neural tube defect prevention globally. The recommendations and strategies are published here.  相似文献   
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