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A petrochemical study of some rock samples has been carried out using different experimental techniques. The rock samples were collected from the Al-Mizil area, Saudi Arabia. Al-Mizil area consists of Precambrian metasediments which belong to the Halaban Formation. The plutonic rocks later intruded into the Halaban Formation. Major oxides and trace elements in these rocks are presented. The study indicates that the rocks are mainly of granitic composition. The petrochemical data suggest a magmatic origin for Al-Mizil granitic rocks.  相似文献   

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Abstract

Oil hydrocarbons represent a great proportion of organic compounds in the atmosphere. Information about these compounds in the atmosphere of the Eastern Province of Saudi Arabia is lacking. In this study, n-alkanes and polynuclear aromatic hydrocarbons in air particulates were determined. The highest median concentration levels of n-alkanes in three urban areas and three areas near oil production centers were 121 ng/m3 and 42.9 ng/m3, respectively. Polynuclear aromatic hydrocarbons were also detected, although they are present in too low concentration for reliable quantitative measurement by GC and GC/MS techniques. A positive correlation was found between the concentration levels of n-alkanes in air particulates and the total suspended particulates measured at most locations. The carbon preference index (CPI) and the presence of the unresolved complex envelope suggested an anthropogenic origin for the n-alkanes.  相似文献   

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Wheat is one of the most grown crops in Saudi Arabia. It is grown in various regions of the country. Accurate knowledge of the elemental concentrations in wheat and its products (bran and flour) is of great importance from a nutritional point of view. Wheat samples were obtained from the Al-Qusim region, 300 km northwest of Riyadh, and analyzed. Up to 50 elements (Al, Sb, As, Ba, Br, Cd, Ca, Cs, Cl, Cr, Co, Cu, Ga, Au, Hf, In, I, Ir, Fe, Mg, Mn, Hg, Mo, Ni, K, Rb, Sc, Se, Ag, Na, Sr, Ta, Te, Th, Sn, Ti, W, U, V, Zn, Zr, Ce, Dy, Eu, La, Lu, Nd, Sm, Tb and Yb) were determined in the wheat products. It was observed that the elemental content of bran was much higher than that of white flour.  相似文献   

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Background: The genus Trichoderma is widely spread in the environment, mainly in soils. Trichoderma are filamentous fungi and are used in a wide range of fields to manage plant patho-genic fungi. They have proven to be effective biocontrol agents due to their high reproducibility, adaptability, efficient nutrient mobilization, ability to colonize the rhizosphere, significant inhibitory effects against phytopathogenic fungi, and efficacy in promoting plant growth. In the present study, the antagonist Trichoderma isolates were characterized from the soil of Abha region, Saudi Arabia. Methodology: Soil samples were collected from six locations of Abha, Saudi Arabia to isolate Trichoderma having the antagonistic potential against plant pathogenic fungi. The soil dilution plate method was used to isolate Trichoderma (Trichoderma Specific Medium (TSM)). Isolated Trichoderma were evaluated for their antagonistic potential against Fusarium oxysporum, Alternaria alternata and Helminthosporium rostratum. The antagonist activity was assessed by dual culture assay, and the effect of volatile metabolites and culture filtrate of Trichoderma. In addition, the effect of different temperature and salt concentrations on the growth of Trichoderma isolates were also evaluated. Results: The most potent Trichoderma species were identified by using ITS4 and ITS 5 primers. Total 48 Trichoderma isolates were isolated on (TSM) from the soil samples out of those six isolates were found to have antagonist potential against the tested plant pathogenic fungi. In general, Trichoderma strains A (1) 2.1 T, A (3) 3.1 T and A (6) 2.2 T were found to be highly effective in reducing the growth of tested plant pathogenic fungi. Trichoderma A (1) 2.1 T was highly effective against F. oxysporum (82%), whereas Trichoderma A (6) 2.2 T prevented the maximal growth of H. rostratum (77%) according to the dual culture data. Furthermore, Trichoderma A (1) 2.1 T volatile metabolites hindered F. oxysporum growth. The volatile metabolite of Trichoderma A (6) 2.2 T, on the other hand, had the strongest activity against A. alternata (45%). The Trichoderma A (1) 2.1 T culture filtrate was proven to be effective in suppressing the growth of H. rostratum (47%). The temperature range of 26 °C to 30 °C was observed to be optimum for Trichoderma growth. Trichoderma isolates grew well at salt concentrations (NaCl) of 2%, and with the increasing salt concentration the growth of isolates decreased. The molecular analysis of potent fungi by ITS4 and ITS5 primers confirmed that the Trichoderma isolates A (1) 2.1 T, A (3) 3.1 and A (6) 2.2 T were T. harzianum, T. brevicompactum, and T. velutinum, respectively. Conclusions: The study concludes that the soil of the Abha region contains a large population of diverse fungi including Trichoderma, which can be explored further to be used as biocontrol agents.  相似文献   

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This work aimed to identify the bioactive constituents of Ducrosia anethifolia Boiss eaves through cold methanolic extract. The GC–MS study of cold methanolic extract showed the presence of various pharmaceutically important bioactive compounds with unique peaks at specified retention time. The significant compounds are α-linoleic acid, α-sitosterol, n-hexadecanoic acid, palmitic acid β-monoglyceride, 2-methoxy-4-vinylphenol and benzoic acid, methyl ester. The FT-IR study showed them fingerprint region at 3326.80, 2943.53, 2831.74, 1450, 1110.67 and 1020.80 cm?1. The FT-IR study suggested the presence of glycosides, flavonoids, tannins, steroids, saponins, fatty acids and squalene. Oral administration of Ducrosia anethifolia Boiss leaves powder (DLP) (100 mg/kg body weight) was successfully reduced the blood sugar level after 14 d treatment in STZ (50 mg/kg bodyweight) induced diabetic rats significantly from 327.93 ± 24.5 to 171 0.03 ± 3.78 mg/dL. Furthermore, DLP (400 mg/kg body weight) was showed 74 ± 1.9 % inhibition of ulcer. The results of this study showed that DLP has both anti-diabetic and anti-ulcer characteristics when tested in vivo.  相似文献   

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At present, hydroxyapatite is being frequently used for diverse biomedical applications as it possesses excellent biocompatibility, osteoconductivity, and non-immunogenic characteristics. The aim of the present work was to recycle bone waste for synthesis of hydroxyapatite nanoparticles to be used as bone extracellular matrix. For this reason, we for the first time utilized bio-waste of cow bones of Albaha city. The residual bones were utilized for the extraction of natural bone precursor hydroxyapatite. A facile scientific technique has been used to synthesize hydroxyapatite nanoparticles through calcinations of wasted cow bones without further supplementation of chemicals/compounds. The obtained hydroxyapatite powder was ascertained using physicochemical techniques such as XRD, SEM, FTIR, and EDX. These analyses clearly show that hydroxyapatite from native cow bone wastes is biologically and physicochemically comparable to standard hydroxyapatite, commonly used for biomedical functions. The cell viability and proliferation over the prepared hydroxyapatite was confirmed with CCk-8 colorimetric assay. The morphology of the cells growing over the nano-hydroxyapatite shows that natural hydroxyapatite promotes cellular attachment and proliferation. Hence, the as-prepared nano-hydroxyapatite can be considered as cost-effective source of bone precursor hydroxyapatite for bone tissue engineering. Taking into account the projected demand for reliable bone implants, the present research work suggested using environment friendly methods to convert waste of Albaha city into nano-hydroxyapatite scaffolds. Therefore, besides being an initial step towards accomplishment of projected demands of bone implants in Saudi Arabia, our study will also help in reducing the environmental burden by recycling of bone wastes of Albaha city.  相似文献   

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This work is concerned with the environmental impact of the cement industry in the west of Saudi Arabia represented in two cement plants and one cement depository. The concentrations of natural and artificial radionuclides in samples of cement (raw materials and end product) and soil, collected from the cement plant and its surrounding area, were measured using γ-ray spectrometer employing a HPGe detector. In addition, the levels of 19 major and trace elements were also determined in these samples using the inductively coupled plasma atomic emission spectroscopy. The concentrations of the 238U series isotopes in soil samples show a clear radiological impact of the cement industry upon the environment. Possible contamination with Ca and some other elements in soil samples that are rich with the fine grain size was observed. Cluster analysis of soil samples using convenient attributes shows an obvious evidence of the cement industry impact upon the environment. The hidden effect of the cement industry upon the environment was observed when the convenient measured attributes were used in cluster analysis of soil samples.  相似文献   

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Different hypotheses have been tested about the fractionation and bioavailability of rare earth elements (REE) in mangrove ecosystems. Rare earth elements and bioavailability in the mangrove ecosystem have been of significant concern and are recognized globally as emerging pollutants. Bioavailability and fractionation of rare earth elements were assessed in Jazan and AlWajah mangrove ecosystems. Comparisons between rare earth elements, multi-elemental ratios, geo-accumulation index (Igeo), and bio-concentration factor (BCF) for the two mangroves and the influence of sediment grain size types on concentrations of rare earth elements were carried out. A substantial difference in mean concentrations (mg/kg) of REE (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) was established, except for mean concentrations of Eu, Gd, Tb, Tm, and Lu. In addition, concentrations of REEs were higher in the Jazan mangrove ecosystem. However, REE composition in the two mangroves was dominated by the lighter REE (LREE and MREE), and formed the major contribution to the total sum of REE at 10.2–78.4%, which was greater than the HREE contribution of 11.3–12.9%. The Post Archean Australian Shale (PAAS) normalized values revealed that lighter REE (LREE and MREE) were steadily enriched above heavy REE. More so, low and negative values of R(H/M) were recorded in the Al Wajah mangrove, indicating higher HREE depletion there. The values of BCF for REEs were less than 1 for all the REEs determined; the recorded BCF for Lu (0.33) and Tm (0.32) were the highest, while the lowest BCF recorded was for Nd (0.09). There is a need for periodic monitoring of REE concentrations in the mangroves to keep track of the sources of this metal contamination and develop conservation and control strategies for these important ecosystems.  相似文献   

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In addition to color, ash and electrical conductivity (EC), the levels of 14 minerals were investigated in 23 varieties of honey from Saudi Arabia and six other countries. The quantities of the macrominerals obtained were as follows (in ppm): K (298.60–491.40), Mg (80.70–199.30), Ca (60.75–99.95), P (21.10–33.29), and Na (15.69–26.93). The quantities of trace minerals were as follows (in ppm): Fe (67.18–98.13), I (12.61–94.68), Mn (4.15–6.04), Zn (3.44–5.72), Li (1.15–4.26), Co (1.00–1.32), and Ni (0.15–0.67). The quantities of the heavy metals Pb and Cd were found to be 0.06–0.23 and 0.00–0.16, respectively. The values of the tested elements—color, ash and EC—varied among the tested honeys according to their botanical origin. Dark honeys, especially acacia honeys, had higher elemental content and EC values than lighter ones. Saudi and Yemeni seder honeys exhibited no distinctive characteristics in their tested parameters. The levels of heavy metals indicated that the tested honeys were safe for human consumption.  相似文献   

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Periplocain A ( 2 ), a new naphthalene derivative together with four known compounds: 2‐ethylhexyl benzoate ( 1 ), quercetin‐3‐Oα‐l ‐rhamnopyranoside ( 3 ), quercetin‐3‐Oβ‐d ‐glucopyranoside ( 4 ), and quercetin‐3‐(6‐Oα‐l ‐rhamnopyranosyl‐β‐d ‐glucopyranoside) ( 5 ) were isolated from the AcOEt fraction of the aerial parts of Periploca aphylla (Asclepiadaceae). Their structures were established by multiple spectroscopic methods in addition to HR‐ESI‐MS and by comparison with literature data.  相似文献   

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Essential oils obtained from plants play critical roles in food and medicine. In this study, the phytochemical composition of Pulicaria crispa essential oil, and its antibacterial, antioxidant and anticancer properties were determined in vitro. The essential oil was extracted from the aerial parts of P. crispa through hydro-distillation using a Clevenger-type apparatus, and it was analyzed with GC-MS. The most dominant chemical constituents of the essential oil were sesquiterpenes (78.26%). The higher constituents were β-caryophyllene oxide (33.97%), modephene (23.34%), geranyl propionate (6.32%), geranyl isovalerate (6.74%), 4-cadinadiene (5%), humulene (4.05%), and β-caryophyllene (2.73%). The essential oil exhibited DPPH radical activity, and it exerted antibacterial effect against gram positive bacteria (Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. However, it had no antibacterial effect on gram negative bacteria (Pseudomonas aeruginosa, Shigella sonnei, Klebsiella pneumoniae and Escherichia coli). The P. crispa essential oil produced significant cytotoxic effects against Hep-G2, MCF-7, Coca-2, and HT-29 ?cells. The oil was most toxic to Hep-G2 cells, based on its IC20 and IC50 values. These results indicate that the essential oil from P. crispa has potent biological properties which can be useful in the food and pharmaceutical industries.  相似文献   

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The levels of several composite elements of two wild plants, namelyEuphorbia terracina andCalotropis procera were evaluated. These plant species are quite abundant all year round in the Makkah province of Saudi Arabia. Leaves from the above plants were collected at 5 km intervals from the sides of two stretches, 50 kilometres each, of two motorways between the cities of Makkah and Taif. One of the motorways (Aljabal motorway) is dominated by petrol fuelled passenger and light goods vehicles whereas the other motorway (Assail motorway) has a significant number of diesel fuelled heavy goods vehicles totalling up to 40% of the traffic volume. Instrumental neutron activation analysis (INAA) was employed with different irradiation and counting conditions. The suitability of the two wild plant species for botanical environmental monitors was investigated and the effects of the different vehicular emissions on the concentration levels of 15 elements is discussed. Control samples from rural environment were also collected and analysed in order to provide baseline levels of the elemental concentrations.  相似文献   

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This study was conducted to create a selenium database for the representative food items in Saudi diet and to estimate the dietary selenium intake of Saudi Arabians. Three samples for each food item selected were purchased from the markets. Each pooled sample was analyzed in triplicate by ICP–MS after thorough homogenization. The rich sources of selenium were meats (0.216–0.658 μg/g), eggs (0.226 μg/g) and cereals and cereals products (0.043–0.165 μg/g). Vegetables and fruits contained trace amounts of selenium (0.001–0.067 μg/g). The major food sources of selenium intake were cereals and cereals products (30.2%), legumes (24.7%) and meats (20%). The daily intake of Se was calculated taking into account the concentration of this element in the edible part and the daily consumption data which were derived from two sources, (a) the food balance sheet of KSA given by Food and Agriculture Organization (FAO) and (b) from questionnaires distributed among 200 families in Jeddah. The results showed that the daily intake of Se according to the two sources is 75.00–121.65 μg/person/day.  相似文献   

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In this study, the levels of natural radioactivity in the groundwater samples collected from 26 different locations in Al-Zulfi, Al-Qassim and Al-Majmaah regions were determined. The estimated average values of 226Ra, 228Ra, 40K, gross α and gross β activities in the samples were 0.87 Bq L?1, 1.33 Bq L?1, 4.22 Bq L?1, 36.82 mBq L?1 and 831.91 mBq L?1, respectively. We found that age-dependent effective ingestion dose from radionuclides in all samples were higher than WHO recommended levels of 0.1 µSv y?1 for adults 0.2 µSv y?1 for children and 0.26 µSv y?1 for infants while 20 sampling locations have age-dependent effective dose equivalent from β contributors were higher than WHO recommended level of 0.1 mSv y?1.  相似文献   

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Journal of Thermal Analysis and Calorimetry - Energy is linked to the most economic and social issues which affect sustainable development of countries. To diversify its economy sources, Saudi...  相似文献   

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《Arabian Journal of Chemistry》2020,13(12):9216-9230
The chloroform (TNC), ethyl acetate (TNE) and n-butanol (TNB) fractions of Tephrosia nubica Bioss. growing in Saudi Arabia were investigated for the first time using UPLC-ESI-MS/MS in two ionization modes. The analysis revealed the tentative identification of 107 compounds. Moreover, the therapeutic potential of T. nubica fractions was determined by in vitro evaluation of their cytotoxic, antioxidant, and anti-obesity activities using MTT assay, DPPH radical scavenging activity and pancreatic lipase inhibitory assay, respectively. The results showed that TNE, TNB, TNC fractions revealed weak antioxidant activity with SC50 139.9 ± 0.8, 144.9 ± 1.5, 148.9 ± 1.3 µg/mL, respectively compared to ascorbic acid 14.2 ± 0.5 µg/ml. Moreover TNE, TNC fractions showed more significant cytotoxic activity against HepG-2 with IC50 82.1 ± 3.1, 101 ± 2.8 µg/mL and MCF-7 with IC50 114 ± 3.2, 124 ± 3.9 µg/mL respectively. The TNB fraction showed weak cytotoxic activity against both cell lines compared to the other fractions. Ultimately, TNE fraction showed a remarkable anti-obesity activity with IC50 62.4 ± 1.5 µg/mL compared to chloroform fraction with IC50 535.6 ± 2.1 µg/mL and n-butanol fraction which did not show any activity. In conclusion, these findings represent the first insights into the phytochemical constituents and pharmacological properties of T. nubica. The ethyl acetate fraction of T. nubica might be a promising source of functional constituents with antioxidant, cytotoxic and anti-obesity potentials. It might be a natural alternative therapy and nutritional strategy, for obesity treatment without dangerous side effects. Isolation of the bioactive compounds from the ethyl acetate fraction of T. nubica and evaluating their biological activities are recommended.  相似文献   

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