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991.
992.
None of the research reports reveals the metabolomics and elemental studies on camel milk. Recent studies showed that camel milk possesses anticancer and anti-inflammatory activity. Metabolomics and elemental studies were carried out in camel milk which showed us the pathways and composition that are responsible for the key biological role of camel milk. Camel milk was dissolved in methanol and chloroform fraction and then vortexed and centrifuged. Both the fractions were derivatized by N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) and TMCS after nitrogen purging and analyzed by GC-MS. Camel milk was also analyzed by ICP-MS after microwave digestion. We found that higher alkanes and fatty acids are present in the chloroform fraction and amino acids, sugars and fatty acid derivatives are present in aqueous fractions. All the heavy metals like As, Pb, Cd, Co, Cu, and Ni were in the safe limits in terms of maximum daily intake of these elements. Na, K, Mg, and Ca were also present in the safe limits in terms of maximum daily intake of these elements. These results suggested that the camel milk drinking is safe and there is no health hazard. The present data of GC-MS and ICP-MS correlate the activities related to camel milk.  相似文献   
993.
Acne vulgaris is a very common skin disorder affecting human beings. There is a paucity of report on the role of heavy metals—lead (Pb) and cadmium (Cd)—globally, and trace metals—zinc (Zn) and copper (Cd)—particularly in Nigeria in the development/severity of acne vulgaris. This study is aimed to determine the blood levels of some heavy metals—cadmium and lead—and trace metals—zinc and copper—in acne vulgaris sufferers in a Nigerian population. Venous blood samples were collected from a total number of 90 non-obese female subjects consisting of 30 mild, 30 moderate and 30 severe acne vulgaris sufferers for blood Cd, Pb, Cu and Zn determination. They were age-matched with 60 females without acne vulgaris who served as the control subjects. Acne sufferers had significantly higher blood Cd and Pb (P = 0.0143 and P = 0.0001 respectively) and non-significantly different blood levels of Cu and Zn (P = 0.910 and P = 0.2140 respectively) compared to controls. There were significant progressive increases in blood levels of Cd and Pb (P = 0.0330 and P = 0.0001 respectively) and non-significant differences in the mean blood level of Cu and Zn (P = 0.1821 and P = 0.2728 respectively) from mild to moderate and severe acne vulgaris sufferers. Increases in blood Cd and Pb may play critical roles in the pathogenesis/severity of acne vulgaris, while Cu and Zn seem to play less significant roles in the development of this disorder in this environment.  相似文献   
994.
995.
996.
This study was performed to determine the chemical composition, antioxidant and cytotoxic effects of essential oils extracted from the aerial parts of fresh (F‐PSEO) and air‐dried (D‐PSEO) Pallenis spinosa. The composition of the oils was analyzed by gas chromatography (GC) and GC/mass spectrometry, the antioxidant activity by free radical scavenging and metal chelating assays, and their cytotoxicity by a flow cytometry analysis. The primary components in both oils were sesquiterpene hydrocarbons and oxygentated sesquiterpenes. F‐PSEO contained 36 different compounds; α‐cadinol (16.48%), germacra‐1(10),5‐diene‐3,4‐diol (14.45%), γ‐cadinene (12.03%), and α‐muurolol (9.89%) were the principal components. D‐PSEO contained 53 molecules; α‐cadinol (19.26%), δ‐cadinene (13.93%), α‐muurolol (12.88%), and germacra‐1(10),5‐diene‐3,4‐diol (8.41%) constituted the highest percentages. Although both oils exhibited a weak radical scavenging and chelating activity, compared to α‐tocopherol and ascorbic acid, D‐PSEO showed a 2‐fold greater antioxidant activity than F‐PSEO. Furthermore, low doses of F‐PSEO were able to inhibit the growth of leukemic (HL‐60, K562, and Jurkat) and solid tumor cells (MCF‐7, HepG2, HT‐1080, and Caco‐2) with an IC50 range of 0.25 – 0.66 μg/ml and 0.50 – 2.35 μg/ml, respectively. F‐PSEO showed a ca. 2 – 3‐fold stronger cytotoxicity against the tested cells than D‐PSEO. The potent growth inhibitory effect of the plant essential oil encourages further studies to characterize the molecular mechanisms of its cytotoxicity.  相似文献   
997.
Applied Microbiology and Biotechnology - This study examines the bioremediation potential and cadmium-induced cellular response on a molecular level in Candida tropicalis 3Aer. Spectroscopic...  相似文献   
998.
999.
Recent Advances in the Regulation of Citric Acid Metabolism in Citrus Fruit   总被引:2,自引:0,他引:2  
The regulation of citric acid metabolism during fruit ripening has a major impact on the production of high-quality fruit. The impact of citric acid on organoleptic fruit quality attributes, fruit storage performance and the synthesis of several secondary metabolites has led to an exponential increase in research efforts during the last two decades. Recent research has focused on the relationship among citric acid biosynthesis, transportation, storage, and utilization. Among citrate metabolic processes, activities of a proton pump, especially the plasma membrane H+-ATPase on tonoplast and citrate catabolism in cytosol play important roles in the regulation of citrate accumulation in cell vacuoles. Moreover, we highlight recent advances and provide an overview of citrate metabolism, postharvest physiology of citrate metabolism, and the influence of agro-climatic factors on citrus fruits. It is the first review that provides a comprehensive model for citrate metabolism in citrus fruit juice sacs. We anticipate that this model for the regulation of citrate metabolism will facilitate the study of fruit acidity in citrus and other nonclimacteric fruits.  相似文献   
1000.
The goal of this study is to identify and characterize the cellulose degrading microorganisms in the larval gut of the white grub beetle, Lepidiota mansueta. Thirty bacterial strains were isolated and tested for cellulolytic activity using soluble carboxymethyl cellulose (CMC) degrading assays. Of these strains, five (FGB1, FB2, MB1, MB2, and HB1) degrade cellulose. Cellulolytic activity was determined based on formation of clear zone and cellulolytic index on CMC plate media. The highest cellulolytic index (2.14) was found in FGB1. Partial 16S rDNA sequencing, morphological, and biochemical tests were used to identify and characterize the five isolates, all Citrobacter sp. (Enterobacteriaceae). This study identifies new cellulose degrading microorganisms from the larval gut of L. mansueta. The significance of identifying these strains lies in possible application in cellulose degradation.  相似文献   
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