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1.
N.  S.  A.  Malik  J.  L.  Perez 《农业科学与技术》2010,(5):61-67
The purpose of this study was to evaluate the quality of the first time commercially produced Texas olive oil. Thus, quantitative assessments of different phenolic compounds in Texas olive versus foreign oils were performed using modern analytical techniques. Samples of commercial and laboratory extracted Texas olive oils were compared with sample from 11 foreign oils. Total polyphenols in each oil sample were measured by the Folin-Ciocalteau method. Individual polyphenols were separated by high performance liquid chromatography and identified by comparing retention time and UV spectra with known compounds. Free acidity and the UV absorption were measured by standard AOCS (American Oil Chemists Society) methods. The Texas olive oil contained 27% higher amounts of total phenols than the highest amount of a foreign oil sample. Similarly, Texas olive oil also contained higher amounts ofoleuropein, hydroxytyrosol, and pinoresinol compared to all other oils tested. Thus, olive oil pressed from olives harvested in hot summer days will be very competitive with other oils with regard to polyphenols contents and hence its health benefits. The free acidity in the commercial Texas oil was 0.35%, based on oleic acid, and its coefficient at K268 UV absorption was 〈0.166. These numbers affirm that the Texas olive is "Extra Virgin".  相似文献   

2.
Phosphorus (P) is a major growth-limiting nutrient, and unlike the case of nitrogen (N), there is no large atmospheric source that can be made biologically available. Moreover, P governs crucial role in plant as it stimulates root development and growth, gives plant rapid and vigorous start leading to better tillering and essential for many metabolic processes for seed formation. Soil microbes play very important role in bio-weathering and biodegradation. The microorganisms produce low molecular mass organic acids, which attack the phosphate structure and transform phosphorus from non-utilizable to the utilizable for the plants form. The test of the relative efficiency of isolated strains is carried out by selecting the microorganisms that are capable of producing a halo/clear zone on a plate owing to the production of organic acids into the surrounding medium. It is a well-known fact that as the particle size of rock phosphate decreases, the microbe mediated solubilization of rock phosphate increases in soil. In the present investigation, microbial solubilization of nano rock phosphate (〈 100 nm) particles was studied. Experimental results revealed that Pseudomonas striata solubilized 11.45% of the total P after 24 h of incubation from nano rock phosphate particles while 28.95% and 21.19% of the total P was solubilized by Aspergillus niger (black pigmented) and Aspergillus niger (green pigmented), respectively. It was also observed that Aspergillus niger has the higher ability to dissolve Udaipur rock phosphate than Pseudomonas striata.  相似文献   

3.
The wastes and the by-products of food industrial technologies are suitable for bioenergy generating because of the high organic matter content. Anaerobic digestion is the eldest technology for waste stabilization and however by controlled decomposition a high value and marketable energy source can be produced. Whey is normally used as a component of dairy products or as an additive for food product. In our work we focused on another utilization method: biogas generating from membrane separated fractions i.e.: permeate and concentrate of whey. The effect of the pH, thermal, microwave pre-treatment and their combinations on the biogas yield were investigated. Our results showed that the applied pre-treatments had significant effect on biogas production. In consequence of the hydrolysis of large molecules the biodegradability of the pre-treated whey fractions was enhanced, therefore the biogas and methane production yield increased significantly.  相似文献   

4.
Forty-five rhizofungal isolates were isolated, identified and characterized from 11 herbicides polluted-soil. Among the isolates, 10 fungal species proved to be the most potent and promising ones in herbicides tolerance. The herbicides exhibited severe and dramatic effect and modulation on fungal DNA and protein represented in DNA and protein profile. Severely loss in the total soluble cell ions (SCI) and total cell protein percentage (TCPC) concentrations were observed. The loss of SCI by glyphosate, Aspergillus flavus (86,30%) was the most affected one, followed by Penicillium spiculisporus (76,30%), Penicilliurn verruculosum (64.40%) and Alternaria tenuissima (64%), respectively. For pendimethalin, Alternaria tenuissima (54.01%) was the most affected fungi. For diclofop-methyl, Penicillium spiculisporus (74.20%) was the most affected fungi. The loss of TCPC by glyphosate, Alternaria tenuissima (64.71%) was the most effected fungi, followed by Penicillium spiculisporus (57.14%), respectively. For pendimethalin, A. terreus (54.29%) w, as the most affected fungi. For diclofop-methyl, Penicillium spiculisporus (60%) was the most affected fungi, fbllowed by Alternaria tenuissima (58.82%), Aspergillus tamarii (55.56%), respectively. The results proved severe reductions and alteration in protein, SCI, TCPC and DNA in fungal strains exposed to these herbicides which might reflex a degree of tolerance occurred during the assimilation of those toxic compounds from the pesticides polluted-soil.  相似文献   

5.
A micropropagation technique is developed for the multiplication of Dendrocalamus strictus (D. strictus), Dendrocalamus asper (19. asper) and Bambusa bambos (B. bambos) through shoot proliferation. Nodal explants obtained from field gown clumps were used to initiate cultures. Shoots were induced on Murashige and Skoog's (MS) medium supplemented with 5 mg L^-1 6-benzylamino purine (BAP). Rapid shoot multiplication was obtained on MS medium containing 3 mg Lt BAP in D. asper, B. bambos and 2 mg L^-1 BAP in D. strictus. In vitro multiplied shoots showed best root induction on half strength MS supplemented with 1 mg L^-1 indole-3 butyric acid (IBA) and 0.5 mg L^-1 1-naphthalene acetic acid (NAA) in D. asper. Pre-rooting conditioning followed by culturing on half strength MS supplemented with 1 mg L^-1 IBA and 2 mg L^-1 IBA showed maximum root induction in D. strictus and B. bambos, respectively. Further root proliferation was obtained on hormone free medium. The micropropagated plantlets were acclimatized and successfully transferred on soil in green house.  相似文献   

6.
The present study deals with the Water Quality Index (WQI) and absorption of zinc from electroplating industry effluent using ftmgi. The physico-chemical parameters such as EC (Electrical Conductivity), TDS (Total Dissolved Solids), total hardness, magnesium, calcium, chloride, sodium, potassium, nickel, chromium and zinc content was above the permissible limits of BIS (Bureau of Indian Standards). The WQI was 13, which showed that the pollution level of the electroplating industry effluent was severe in the rating scale and the effluent was not suitable for disposal without treatment. Three fungal species such as Aspergillus niger, Peinicillium chrysogenum and Rhizopus nigricans were used for absorption studies. Different concentrations (25, 50, 75 and 100%) of electroplating industry effluent along with 1 gm of fungal mycelium with (1%) and without carbon source was incubated in a shaker for a period of 7 days in order to observe zinc absorption capacity. The absorption capacity of zinc was found to be higher in Aspergillus niger followed by Rhizopus nigricans and Penicillium chrysogenum. Among the three fungal species Aspergillus niger had high (50%) potential of zinc absorption with carbon source and low concentration (25%) of electroplating industry effluent.  相似文献   

7.
Large amounts ofFlaveria bidentis's root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-~) can have a certain inhibition on Triticum aestivum, Cucumis sativus, Raphanus sativus, Amaranthus retroflexus, Setaria viridis, Chenopodium album, Echinochloa crusgalli and Chloris virgata. This outcome suggested some active compounds in the root exudates ofFIaveria bidentis can inhibit the germination, seedling elongation and root length. The dichloromethane extract of root exudates was identificated by GC-MS, and 29 kinds of compounds, including esters, hydrocarbons, ketones, thiazole, amines, etc. were obtained and the phthalate n-octyl ester, phthalate 2-ethylhexyl ester were proved to be allelochemicals. The culturing solution of root exudates was separated through the resin column and silica gel column and a component inhibiting seedling height, root length and fresh weight of wheat was got. There were 6 kinds of organic compounds in this component including dioctyl phthalate, 1,2-phthalate, mono(2-ethylhexyl) ester by GC-MS.  相似文献   

8.
The present study was aimed to investigate the anti-arthritic activity of alcoholic extract ofClerodendron inerme which was shown to inhibit inflammatory process. Arthritis was induced in rats by injecting rats intradermally with Freund's adjuvant 0.01%-0.1% in paraffin oil. They were grouped and received 10 mg/100 gm b.wt. of alcoholic fraction of C. inerme, 1.5 mg/100 gm b.wt. hydrocortisone and saline, orally, for 15 days. The arthritic scores, radiological scores, body weights, liver glycogen, serum mucoproteins were monitored for 49 days. Wilcoxan ranking methods and Student's t Test were used to determine the significance changes between control and treated groups. Adjuvant-arthritic rats showed a significant decrease in body weight, liver glycogen, increased serum mucoprotein and severity of periostitis and other degenerative changes m the bone. But treatment with the alcoholic fraction (apigenin, scutallarin and pectinolinergenin) of C. inerme exhibited a very good relief from the arthritic conditions by increasing the body weight, increased liver glycogen content and registered little degenerative changes in bones, suggesting long term anti-arthritic activity when compared to the control group. The anti-arthritic activity ofC. inetme alcoholic fraction was remarkable in this study. However, further studies are required to elucidate its full anti-arthritic potential.  相似文献   

9.
The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (WSS), humic acid (HA), fulvic acid (FA) and humin (HU) were determined to explore the impact of long-term fertilization on HS. Increases in the amounts of WSS, HA, FA and HU were significant different among the treatments with manure. A significant correlation was found between the increased soil organic carbon (SOC) and HS (R^2=0.98, P〈0.01). The change in the E4/E6 ratio was significantly correlated with the increased SOC (R2=0.88, P〈0.01), HA (R^2=0.91, P〈0.01), FA (R^2=0.91, P〈0.01) and HU (R^2=0.88, P〈0.01). The cluster was mainly divided into two parts as manure fertilization and inorganic fertilization, based on the increases in HA, FA and HU. These results suggest that long term fertilization with manure favours carbon sequestration in HS and is mainly stabilized as HU, while the HA becomes more aliphatic. We conclude that increases in SOC can be linked to changes in the molecular characteristics of HS fractions under long term fertilization.  相似文献   

10.
In the present study, it has been aimed to determine the non target effects of Congo red on soil enzyme activities namely amylase, protease, catalase, glucose oxidase and laccases, following the standard procedures. Further, it is also aimed to decolourize the dye effluents by using immobilized fimgal cultures namely Aspergillus spp. isolated from textile effluents and estimate the percentage of decolourization by dye decolourization assay method. The selected fungi were found efficient and dominant type in dye decolourization with the production of laccase and other enzymes. Except laccase, all the enzymes showed maximum activity at 14 days followed by declining trend at 21 days. Maximum enzyme activity was noticed with Aspergillus niger. 95% of decolourization was found within 4-24 h in sodium alginate immobilized fungal cultures compared to controls. The above results clearly indicate the efficiency of these fungi in selective bioremediation of dye contaminated sites.  相似文献   

11.
A halotolerant, gram positive, motile and rod, was isolated from the E1 Gol6a lake of Ghardaia, Alegria and screened for its antimicrobial potential. The strain showed an inhibitory effect to gram positive and gram negative bacteria against Cladosporium spp. and a slight inhibitory effect against C. albicans using chloroform as the extraction solvent and the nutrient broth as production medium. 16S rRNA sequencing showed that the isolate named LMB3981 is a new taxon in the family of Bacillaceae (with 96% similarity). The strain is close to Filobacillus milosensis and Bacillus haloalkaliphilum with 95% similarity. The phenotypic study showed differences between LMB3981 and two strains that are near and have confirmed the results of 16S rRNA sequencing by specific metabolic properties of the strain.  相似文献   

12.
The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), the second location is situated in Koradeer village that covered with threes of Prunus dulcis (Mill.) Webb.. Disturbed surface soil samples at depth 0-30 cm were collected at four different distances (1, 5, 10 and 15 m) from the tree with randomized selection three trees in each study location. Soil organic matter decreases with increasing distances from tree in both locations under two different trees species, which is attributed to the effect of tree crown. Ordinarily, organic matter content in both locations correspond to the requirements of Mollisols. Statistical analysis of data showed significant differences in organic matter content between locations. Cation exchange capacity is high under tree crown and decreasing with distances from tree in both locations, as a result of decreasing organic matter and increasing calcium carbonate with distances. Commonly soil pH is slightly increased with increasing distances from tree because of increasing calcium carbonate with distances and decreasing organic matter content. Calcium was not uniform with distances and Mg decreasing with distances in both locations. The values of fine clay/coarse clay and fine clay/total clay of soil samples confirm development of the soils under study. Porosity percentage under tree crown is high and decreasing with distances. Soil bulk density was increased with distances in both locations, as a result of decreasing organic matter content with distances. This study aims to explain the effect of tree distances and species on the mollic horizon properties.  相似文献   

13.
To determine the potential effects of climate change on crop phenological development and productivity, an integrated analysis was conducted based on the observed climatic and phenological records of Northeast China from 1992 to 2012. A set of quality assurance procedures, including repeated record checks, agro-meteorological station selection, internal consistency checks, temporal outlier checks, spatial outlier checks, and interpolation of missing data, were designed and applied to the phenology datasets of spring maize and paddy rice. Our results indicated that almost all phenological dates of spring maize and paddy rice became increasingly delayed from 1992 to 2012, The duration of the growing season was prolonged, particularly for the grain-filling stage (GS3). The prolonged growing season was beneficial to productivity. For spring maize, the average precipitation during GS3 decreased at a rate of 27.46 mm/decade, and the annual accumulated temperature over 10℃ increased at a rate of 31.07℃/ decade. Farmers initiatively adjusted crop cultivars and selected drought-resistant crops to cope with the challenges of drought.  相似文献   

14.
An anaerobic digestion unit for producing biogas from cow dung in the rural communities was designed, fabricated and tested for performance, durability and throughput. The major components of the digester included the substrate holding tank, tank cover, agitator, debris collector, inlet and outlet pipes, gas reception tank, hose and heat source. The digester is a vertical cylindrical tank with an inlet pipe for the introduction of substrate and an outlet pipe to collect the digested substrate. An agitator is incorporated inside the digester to break scum on the substrate and create uniform temperature profile in the digester while a pressure gauge was fitted to the gas outlet valve to measure the gas pressure in the tank. The agitator shaft is extended outside to be driven by an electric motor through belt and pulley system. The criteria considered in the design of the digester included air tightness of the system, mesophilic and thermophilic temperature, nature and type of substrate used, substrate retention period, number of crank turns per minute and volumetric capacity of the digestion tank. Other considerations included the desire to make the digestion tank and gas reception tank of galvanized steel to ensure good quality of the product and the need for a strong structural support to ensure structural stability of the system. After construction and assembly, the biogas digestion unit was tested with 40 kg of cow dung diluted with 80 kg of water and subjected to a retention period to make a substrate (slurry) of 10 % total solid (TS). Daily gas yield was determined; gas pressure in the tank was measured by the pressure gauge, while the ambient temperature was taken at five hours interval. Results showed that a cumulative gas yield of 0.415 litres after 22 d retention period at average substrate temperature and pH of 29 ℃ and 6.2, respectively. The digester has a substrate holding capacity of 330.8 litres and a production cost of $375 with all the construction materials being available locally.  相似文献   

15.
Changes in drought trends and its relationship with climate change in China were examined in this study. The temperature vegetation drought index (TVDI) datasets recorded during 2001 to 2010 in China were constructed by using the moderate-resolution imaging spectroradiometer (MODIS) data, and the temporal and spatial variations in drought were analyzed. In addition, the mean temperature, mean precipitation, mean relative humidity, and mean sunshine duration data collected from 557 local weather stations in China were analyzed. The relationships between drought and these climate factors were also analyzed by using correlation analysis and partial correlation analysis. Changes in drought tendency were shown to differ among four regions throughout the country. The lfuctuations in climate in the regions of northeastern China, Qinling-Huaihe, and central Qinghai were caused by the increase in soil moisture, and that in southern Tibet was caused by the intensiifcation of drought. Meteorological factors exhibited varied effects on drought among the regions. In southern China, the main inlfuential factor was temperature;other factors only showed minimal effects. That in the northern and northwestern regions was sunshine duration, and those in the Qinghai-Tibet Plateau were relative humidity and temperature.  相似文献   

16.
The objective of this study was to determine the efficiency of different plant systems in capturing deep soil nitrate (NO3-) to reduce NO3- leaching in a field plot experiment using 15N labelling. The study was conducted on a calcareous alluvial soil on the North China Plains and the plant systems evaluated included alfalfa (Medicago sativa), American black poplar (Populus nigra) and cocksfoot (Dactylis). ^15N-labelled N fertilizer was injected to 90 cm depth to determine the recovery of ^15N by the plants. With conventional water and nutrient management, the total recovery of ^15N-labeled NO3--N was 23.4% by alfalfa after two consecutive growth years. The recovery was significantly higher than those by American black poplar (12.3%) and cocksfoot (11.4%). The highest proportion of soil residual ~SN from the labeled fertilizer N (%Ndff) was detected around 90 cm soil depth at the time of the 1st year harvest and at 110-130 cm soil depth at time of the 2nd year harvest. Soil %Ndff in 0-80 cm depth was significantly higher in the alfalfa treatment than those in all the other treatments. The soil %Ndff below 100 cm depth was much lower in the alfalfa than those in all the other treatments. These results indicated that ^15N leaching losses in the alfalfa treatment were significantly lower than by those in the black poplar and cocksfoot treatments, due to the higher root density located in nitrate labeling zone of soil profile. In conclusion, alfalfa may be used as a plant to capture deep soil NO3- left from previous crops to reduce NO3- leaching in high intensity crop cultivation systems of North China Plain.  相似文献   

17.
The present study achieves the biochemistry partial characterization of the chitinolytic extract produced by an endophytic Streptomyces sp. strain (A8). This extract was also tested against Anthonomus grandis, the cotton boll weevil aiming its control. The chitinase crude extract from the A8 strain was cultured for five days in a minimum liquid media supplemented with chitin. The extract was partially characterized by standard methods. The chitinolytic extract had an optimum temperature of 66 "C and an optimum pH between 4 to 9 (around 80% of relative activity). We also characterized the temperature and pH stability and measured the effects of enzyme inhibitors. The filtered chitinolytic extract was added to an artificial boll weevil diet. Boll weevil development from the egg stage to the adult stage was prolonged, and the percentage of adults that emerged was approximately 66% less than on control diet. This study showed that the.larval development of A. grandis was inhibited by the presence of characterized chitinolytic extract in artificial diet. This work provides an experimental basis for using the chitinase from an endophytic bacterium Streptomyces sp. as a biocontrol alternativeto controlling the plant pest A. grandis.  相似文献   

18.
Essential oils (EOs) from Rosemary, Rosmarinus officinalis (Lamiaceae), Orange, Citrus sinensis (Rutaceae), Lavandula, Lavandula angustifolia (Lamiaceae), False Yellowhead, Dittrichia viscosa (Asteraceae) and their major components were evaluated against root knot nematode, Meloidogyne incognita and Meloidogynejavanica. Second stage juveniles' (J2) paralysis and egg hatch inhibition were studied, while pulverized plant parts were tested for nematodes biological cycle arrest. All EOs paralyzed J2 and M. incognita were found more sensitive than M javanica with the EC50/4 days calculated at 250, 3,650 and 4,260 12g/mL for 1). viscosa, L. angustifolia and R. officinalis, respectively. Similarly, all EOs inhibited nematodes egg hatch and D. viscosa exhibited the highest inhibition on egg hatch (100% inhibition at 5 μg/mL). A significant influence of constituent terpenes (limonene, 1,8-cineole, linalool, camphor, L-borneol, caryophyllene oxide, β-eudesmol) dose and exposure time was indicated on egg hatch inhibition (56% to 100% at 500 μg/mL and 1,000 μg/mL), while only β-eudesmol achieved paralysis of J2 and specifically against M. incognita (EC50/1d = 50μg/mL). Interestingly, the most active botanical species arresting Meloidogyne spp. biological cycle in soil was C. sinensis (EC50 = 2 mg/g) and the most sensitive nematode species was M. javanica. The larvicidal and egg hatch inhibition activity holds promise towards the optimization of artificial terpene mixtures as novel and effective natural nematicides. Complex interactions of primary compounds and subsequent decomposition derivates compose efficacy profile of soil amendments.  相似文献   

19.
Long-chain acyl-Coenzyme A (CoA) synthetases (LACSs) catalyze the formation of long-chain acyl-CoA, and play important roles in fatty acid metabolism including phospholipids, triacylglycerol (TAG) biosynthesis and fatty acid 13-oxidation. Here, we report the characterization of a LACS gene from Brassica napus. It is highly homologous to Arabidopsis LACS4 and thus designated as BnLACS4. The cloned gene BnLACS4 could complement a LACS-deficient yeast strain YB525. It is mainly expressed in flowers and developing seeds where lipid biosynthesis is at high rate in Brassiea napus. When transiently expressed in tobacco leaves, BnLACS4 is localized in endoplasmic reticulum (ER), the common site for eukaryotic pathway of lipid biosynthesis. Expression of BnLACS4 in the yeast strain pep4 increased its lipid content. Taken together, our results suggest that BnLACS4 may be involved in lipid biosynthesis in B. napus.  相似文献   

20.
Farmers may not be conscious for their farmland's nutrients, soil organic matter, water and air because they simply concerned only for their labor availability and soil fertility losses. The composition and proportion of these components greatly influence soil physical properties, including texture, structure and porosity, the fraction of pore space in a soil. The soil of this farmland must be able to supply adequate amount of plant nutrients, in forms which can be absorbed by the crop, within its lifespan. Deficiencies or imbalances in the supply of any of essential elements can compromise growth, affecting root development, cell division, crop quality, crop yield and resistance to disease and drought. This study was conducted to fill this knowledge gap in order to develop economically vital and environmentally accepted nutrient management strategies for the use of soils in agricultural lands. The objective of this study is to assess the elemental contents and concentration of soil samples collected from farmlands of "Yebrage" using neutron activation analysis (NAA) techniques regardless of oxidation state, chemical form or physical locations. NAA is used to determine the elemental composition and concentrations present in a soil. The macro/micronutrient and organic matter deficiencies have been verified in agricultural soils through increased use of soil testing and plant analysis. The challenge for agriculture over the coming decades will meet the world's increasing demands for food in a sustainable way. Current issues and future challenges point out that as long as agriculture remains a soil based industry, major decreases in productivity likely to be attained ensuring that plants do not have adequate and balanced supply of nutrients.  相似文献   

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