Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the pr...Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the production of aflatoxin in liquid media using strains of Aspergillus flavus obtained from peanuts marketed in the city of Fortaleza, CEo Strains of Aspergillus flavus were inoculated into a liquid medium malt extract and after 2 days inoculated into a second medium containing sucrose 5%, MgSO4·7H20 0.1%, KH2PO4 1%, ZnSO4·7H2O 0.0176 g, and cultured for 3 more days. The media were kept at room temperature ranging from 24°C to 32 °C with agitation of 130 rpm and aeration of 4.17 Llmin. Qualitative analysis was performed by thin layer chromatography and quantitatively by high performance liquid chromatography with fluorescence detection, demonstrating the production of aflatoxin B I （588 mg/L） and B2 （929 mg/L）.展开更多
Date palm, like all other crops, is very sensitive to the injury by many insect pests, which may lead to the death of the affected plant and causes decrease in yield. In the present study, an efficient Agrobacterium f...Date palm, like all other crops, is very sensitive to the injury by many insect pests, which may lead to the death of the affected plant and causes decrease in yield. In the present study, an efficient Agrobacterium for genetic transformation was successfully achieved for well known date palm （Phoenix dactylifera L.） cv. Medjool and Khalas using callus as explant. Embryogenic callus were recorded 100% mortality when cultured on MS medium containing 100 mg/L kanamycin with different cultivars, thus it was chosen for the selection of transformed explants. Embryogenic callus of Medjool and Khalas were incubated with Agrobacterium tumefaciens strain LBA 4404 for 0.5, 1, 2, 4 and 24 h on LB medium. After the incubation periods, embryogenic callus was transferred to MS medium with 0.1 mg/L NAA, 0.05 mg/L BA, 250 mg/L carbenicillin and 100 mg/L kanamycin for detection of transgenic embryogenic callus. Polymerase chain reaction （PCR） was used for the rapid screening of Cry3Aa gene. For screening, total genomic DNA was isolated from transformants. Using primer specific to Cry3Aa gene （forward and reverse）, a PCR product with a size of about 2,000 bp was amplified when all nucleic acid from the transformants were utilized as templates. PCR analysis confirmed the appearance of the transgene of 2,000 bp in one individual plantlet. Presence and integration of foreign Cry3Aa gene in regenerated kanamycin resistant embryogenic callus was also confirmed by Southern blot hybridization. It was found that one transgenic embryogenic callus for both Medjool and Khalas showed a single copy of gene integration. These results signify the successful transfer of Cry3Aa gene into date palm plant.展开更多
Toxicity of the different concentration of Cu^2＋ to the wheat seeding and its distribution in the plant were studied by solution culture. The results showed that： The correlation between the content of Cu^2＋ in med...Toxicity of the different concentration of Cu^2＋ to the wheat seeding and its distribution in the plant were studied by solution culture. The results showed that： The correlation between the content of Cu^2＋ in medium and the germination and growth of the seedlings is significant （P〈0.01）. The effect of Cu^2＋ to the germination, plant height, fresh weight, dried weight and the chlorophyll mount of the wheat seedling was stimulated under lower concentration of Cu^2＋ and was inhibited under higher concentration. With the increase of the Cu^2＋ concentration in the culture solution, the germination and growth of the seedlings was inhibited. The perfect positive correlation between the Cu^2＋ content in the plant and that in the culture solution was noted. Most of Cu^2＋ was concentrated in the root, and only a small amount was migrated to the aerial part of the wheat seedling. The sensitivity of each index to the Cu^2＋ concentration was ranked as follows： the Cu^2＋ content in the plant〉chlorophyll-a〉the ratio of chlorophyll-a to chlorophyll-b〉total chlorophyll〉plant height 〉germination〉fresh weight〉root elongation〉 chlorophyll-b 〉dried weight. The Cu^2＋ content in the wheat plant was the most sensitive index to the Cu^2＋ concentration in the culture solution.展开更多
Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cult...Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cultured first in the selective media Ashdown＇s broth then subcultured on Ashdown＇s agar to isolate Burkholderia pseudomallei which was recovered from seven cases （8.33%）. Four isolates were from renal failure patients （23.53%）, two from diabetic patients （11.76%） and the seventh isolate was from an outpatient with tonsillitis. All isolates were able to produce capsules, form filament chains, exhibit swarming motility and were arabinose non assimilators （Ara-） indicative of their virulence. Additionally, isolated B. pseudomallei were found to produce protease, lipase, hemolysin, and lecithinase and were able to produce biofilm, the root of many troublesome persistent infections that resist antibiotic treatment. Susceptibility of the seven isolates of B. pseudomallei toward 11 antibiotics was assessed, isolates were found multiply resistant to all antibiotics apart from ciproflaxin. This study confirms for the first time isolation of B. pseudomallei from immunocompromised patients in Basrah city of Iraq and describes their virulence potentials.展开更多
文摘Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the production of aflatoxin in liquid media using strains of Aspergillus flavus obtained from peanuts marketed in the city of Fortaleza, CEo Strains of Aspergillus flavus were inoculated into a liquid medium malt extract and after 2 days inoculated into a second medium containing sucrose 5%, MgSO4·7H20 0.1%, KH2PO4 1%, ZnSO4·7H2O 0.0176 g, and cultured for 3 more days. The media were kept at room temperature ranging from 24°C to 32 °C with agitation of 130 rpm and aeration of 4.17 Llmin. Qualitative analysis was performed by thin layer chromatography and quantitatively by high performance liquid chromatography with fluorescence detection, demonstrating the production of aflatoxin B I （588 mg/L） and B2 （929 mg/L）.
文摘Date palm, like all other crops, is very sensitive to the injury by many insect pests, which may lead to the death of the affected plant and causes decrease in yield. In the present study, an efficient Agrobacterium for genetic transformation was successfully achieved for well known date palm （Phoenix dactylifera L.） cv. Medjool and Khalas using callus as explant. Embryogenic callus were recorded 100% mortality when cultured on MS medium containing 100 mg/L kanamycin with different cultivars, thus it was chosen for the selection of transformed explants. Embryogenic callus of Medjool and Khalas were incubated with Agrobacterium tumefaciens strain LBA 4404 for 0.5, 1, 2, 4 and 24 h on LB medium. After the incubation periods, embryogenic callus was transferred to MS medium with 0.1 mg/L NAA, 0.05 mg/L BA, 250 mg/L carbenicillin and 100 mg/L kanamycin for detection of transgenic embryogenic callus. Polymerase chain reaction （PCR） was used for the rapid screening of Cry3Aa gene. For screening, total genomic DNA was isolated from transformants. Using primer specific to Cry3Aa gene （forward and reverse）, a PCR product with a size of about 2,000 bp was amplified when all nucleic acid from the transformants were utilized as templates. PCR analysis confirmed the appearance of the transgene of 2,000 bp in one individual plantlet. Presence and integration of foreign Cry3Aa gene in regenerated kanamycin resistant embryogenic callus was also confirmed by Southern blot hybridization. It was found that one transgenic embryogenic callus for both Medjool and Khalas showed a single copy of gene integration. These results signify the successful transfer of Cry3Aa gene into date palm plant.
文摘Toxicity of the different concentration of Cu^2＋ to the wheat seeding and its distribution in the plant were studied by solution culture. The results showed that： The correlation between the content of Cu^2＋ in medium and the germination and growth of the seedlings is significant （P〈0.01）. The effect of Cu^2＋ to the germination, plant height, fresh weight, dried weight and the chlorophyll mount of the wheat seedling was stimulated under lower concentration of Cu^2＋ and was inhibited under higher concentration. With the increase of the Cu^2＋ concentration in the culture solution, the germination and growth of the seedlings was inhibited. The perfect positive correlation between the Cu^2＋ content in the plant and that in the culture solution was noted. Most of Cu^2＋ was concentrated in the root, and only a small amount was migrated to the aerial part of the wheat seedling. The sensitivity of each index to the Cu^2＋ concentration was ranked as follows： the Cu^2＋ content in the plant〉chlorophyll-a〉the ratio of chlorophyll-a to chlorophyll-b〉total chlorophyll〉plant height 〉germination〉fresh weight〉root elongation〉 chlorophyll-b 〉dried weight. The Cu^2＋ content in the wheat plant was the most sensitive index to the Cu^2＋ concentration in the culture solution.
文摘Eighty four throat swabs were obtained from Basrah General Hospital inpatients （N = 34）： 17 were suffering from renal failure and the other 17 were diabetics; and from outpatients （N = 50）. Throat swabs were cultured first in the selective media Ashdown＇s broth then subcultured on Ashdown＇s agar to isolate Burkholderia pseudomallei which was recovered from seven cases （8.33%）. Four isolates were from renal failure patients （23.53%）, two from diabetic patients （11.76%） and the seventh isolate was from an outpatient with tonsillitis. All isolates were able to produce capsules, form filament chains, exhibit swarming motility and were arabinose non assimilators （Ara-） indicative of their virulence. Additionally, isolated B. pseudomallei were found to produce protease, lipase, hemolysin, and lecithinase and were able to produce biofilm, the root of many troublesome persistent infections that resist antibiotic treatment. Susceptibility of the seven isolates of B. pseudomallei toward 11 antibiotics was assessed, isolates were found multiply resistant to all antibiotics apart from ciproflaxin. This study confirms for the first time isolation of B. pseudomallei from immunocompromised patients in Basrah city of Iraq and describes their virulence potentials.
