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H. Salehi
Abstract: This investigation was conducted to find the best shoot proliferation and rooting media for 13 virus-free cultivars of carnation (Dianthus caryophyllus L.) recently imported from The Netherlands to Iran. The best shoot proliferation media were Murashige and Skoog (MS) containing 3 mgL-1 (13.95 mM) kinetin and 0.5 mgL-1 (2.69 mM) NAA or 1 mgL-1 (4.44 mM) BA and 1 mgL-1 (5.37 mM) NAA. Average of shoot numbers produced in the establishment media was 2-3, which increased to 30 or higher with some cultivars in subsequent subcultures. For rooting, the in vitro shoots were cultured on the best MS rooting media which is discussed. Transferring to a mixture of sand, leaf-mold and vermiculite (1:1:1, v/v/v) successfully acclimatized the plantlets. It can be concluded that using a general medium for shoot proliferation of used carnation cultivars is possible, but for rooting it is impossible.[...] Read More.
Keywords: culture medium, Dianthus caryophyllus L., in vitro culture, micropropagation.
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concentrations of growth hormone, thyroid hormones and the amount and constituents of milk in the Sanan goat
Abstract: The goal of this study was to determine whether serotonin increase the mean plasma concentrations of thyroxine (T4), triiodothyronine (T3), growth hormone (GH), milk amount and constituents in the Sanan goats. Nine Sanan goats were randomly divided into 3 groups. Each group received daily infusion of 1, 4 or 8 ng serotonin agonist (hydroxytryptophan) (5HT) for 7 days. Blood and milk samples were collected daily on day 1 before infusions until 3 days after the last infusion. Samples were assayed for plasma T3, T4 and GH concentrations by double-antibody RIA. Milk samples were assayed for protein, fat and lactose constituents. The daily amounts of milk were determined throughout the experiment. Infusions of 1 ng 5HT did not change the plasma concentrations of the T3, T4 and GH throughout the experiment period. Infusions of 4 and 8 ng 5HT significantly (p[...] Read More.
Keywords: Serotonin T3, T4, GH, Sanan goats.
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B.H. Guo, G.Y. Kai, H.B. Jin and K.X. Tang, *
Abstract: Being a complex diterpenoid, the potent anticancer drug, Taxol, requires complicated steps for its biosynthesis. In the present article, recent advances on Taxol biosynthesis pathway are reviewed, including many recently reported genes that regulate Taxol biosynthesis. To meet the urgent need of clinic and scientific research, besides Taxus supply, other approaches to obtain Taxol have also been discussed here.[...] Read More.
Keywords: biosynthesis pathway, cell culture, endophytic fungi, Taxol, Taxus.
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文章
E. Olatunde Farombi*
Abstract: Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer mortality in the world and, in certain parts of Asia and Africa, it accounts for about 70% of cancer deaths. Chronic hepatitis B virus (HBV) infection and dietary exposure to aflatoxin B1 (AFB 1) are the two major risk factors in multi factorial aetiology of HCC. Multiple lines of evidence indicate synergistic interaction between these two agents in the development of HCC. Several mechanisms of interaction have been suggested including activation of cytochrome P450s by HBV infection leading to the metabolism of inactive AFB1 to the mutagenic AFB 1-8,9-epoxide as well as the generation of reactive oxygen species by HBV and AFB1 sensitising the cells to AFB1-induced p53 249ser mutations. The poor survival rate achieved by the current surgical procedures and chemotherapy treatment has motivated a number of scientific investigations to elucidating the molecular events involved in HCC thus providing the scientific rationale for prevention strategies, including primary and chemoprevention approaches. Recent findings have implicated intracellular signalling cascades involving nuclear factor kappa B (NF-kB) and nuclear transcription factor erythroid 2p45 (NF-E2)-related factor 2 (Nrf2) as molecular targets of a wide range of chemopreventive agents. The new findings thus raise the intriguing possibility that chemopreventives modulating these molecular targets in the liver might provide a novel therapeutic approach to the development of liver cancer.[...] Read More.
Keywords: Hepatocellular carcinoma, chronic hepatitis B virus, aflatoxin B1, chemoprevention.
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Identification of metallo-b-lactamase from a clinical isolate at Saint Camillle medical Center of Ouagadougou, Burkina Faso
Abstract: A metallo-b-lactamase was identified from a clinical sample. The host bacteria was identified to be Chryseobacterium indologenes. This preliminary characterization of the enzyme is reported here.[...] Read More.
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Studies on the extraction and characterization of thermostable a-amylase from pericarp of Borassus indica
Abstract: Thermostable a-amylase was extracted and characterized from the fruits (pericarp) of Borassus indica. Analysis on the influence of various physico-chemical parameters on the extracted enzyme revealed a Vmax of 0.793 and a Km of 0.022. The optimum temperature was found to be 370C at pH 4.5. The stability studies on enzyme activity envisaged that the enzyme is stable up to 800C and retained its activity over a wide range of pH (4.0 – 8.5). Significant enhancement in the enzyme activity was observed in the presence of metal ions like Manganese and Strontium and an insignificant decrement in the presence of Sodium ions.[...] Read More.
Keywords: a-Amylase, Borassus indica, enzyme activity.
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Mariana CORTEZI, Rubens MONTI and Jonas CONTIERO*
Abstract: Temperature (23 to 31°C) and sucrose concentration (3 and 4%) effects on dextransucrase production by Leuconostoc mesenteroides NRRL B 512 (F) and Leuconostoc mesenteroides FT 045 B were studied. The conditions in all fermentations were: total reaction volume 2 L, 132 rev. min-1, 0.5 vvm and pH 6.0. The optimum temperature for enzyme yield for strain NRRL B 512 (F) was 23°C, where at 8-h fermentation was possible to achieve 49.3 DSU/mL. When FT 045 B strain was utilized, 3.2 DSU/mL was obtained at temperature 23 to 25 °C.[...] Read More.
Keywords: Dextran, dextransucrase, Leuconostoc mesenteroides NRRL B512 (F), Leuconostoc mesenteroides FT045 B, temperature, enzyme activity.
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Roger PONKA*, Elie FOKOU, Rose LEKE, Martin FOTSO, Jacob SOUOPGUI, Mercy ACHU BIH and Félicité MBIAPO TCHOUANGUEP
Abstract: This study deals with the description of the methods of preparation and determination of the nutritional potential of dishes consumed by Cameroonians living in a rural area, which is a malaria endemic zone, called Ngali II. The dishes consumed are prepared from leguminous seeds, seeds of the Cucurbitaceae family (egusi seeds), green leafy vegetables, tubers, cereals unripe bananas and plantains. The contents in moisture, ash, proteins, lipids, crude fibres and carbohydrates were determined by standard AOAC methods. The results obtained are expressed in percentage f.w for moisture and percentage d.w for ash, proteins, lipids, crude fibres and carbohydrates. The moisture content ranges from 57.77-86.17; ash, 0.66-14.74; proteins, 1.49-37.25; lipids, 0.26-54.98; crude fibres, 1.43-17.82 and carbohydrates, 3.51-95.76. This study revealed that a higher consumption of dishes made from leguminous seeds, egusi seeds, green leafy vegetables, and low consumption of tubers, unripe bananas and plantains will lead to a good nutritional balance. Keywords: Dishes, preparation, nutritional potential, malaria.[...] Read More.
Keywords: Dishes, preparation, nutritional potential, malaria.
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Angela Faustino Jozala, Letícia Célia de Lencastre Novaes, Olivia Cholewa, Dante Moraes, Thereza Christina Vessoni Penna*
Abstract: Nisin production related to the growth conditions of Lactococcus lactis subsp. lactis ATCC 11454, the effects of various media components and concomitant release of nisin into the media, were studied through transfers (five times). Nisin production was assayed by agar diffusion using Lactobacillus sake ATCC 15521 as the sensitive test organism. The expression of nisin was strongly influenced by the addition of skimmed milk to both MRS and M17 broth, with the highest production obtained after the second and the fifth transfers, respectively, with maximum expression after 36 h of incubation.[...] Read More.
Keywords: Nisin, Lactococcus lactis, Lactobacillus sake, bacteriocin, milk.
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B. O. Ejechi* and D. E. Akpomedaye
Abstract: A previous report showed that the essential oil and phenolic acid extracts of pepperfruit (Dennetia tripetala) inhibited the growth of tomato-rot fungi. The study was subsequently extended to other food-borne microorganisms (Staphylococcus aureus, Salmonella sp. Pseudomonas aeruginosa., Proteus sp., Escherichia coli., Enterococcus faecalis., Serratia sp., Bacillus sp., Clostridium sp., Penicillium sp., Aspergillus flavus) isolated from food products. All the isolates were susceptible to the extracts with a minimum inhibitory concentration (MIC) range of 1.0-4.0 mg/ml. The essential oil inhibited the food-borne organisms better (MIC: 1.0-2.5) than the phenolic acid (MIC: 1.5-4.0). The challenge organisms in fresh, boiled or roasted beef, treated with the extracts were either not detected, declined significantly in number (p0.05) after 7 days. A role for pepperfruit extracts in natural food protection is further indicated.[...] Read More.
Keywords: Essential oil, pepperfruit, dennetia tripetala, phenolic acid, food-borne microorganisms.
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