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141.
Shaikhul Islam Abdul Mannan Akanda Farjana Sultana 《Archives Of Phytopathology And Plant Protection》2013,46(10):1231-1238
A rhizosphere fungus was isolated from roots of chilli plants and identified as Aspergillus spp. PPA1. The fungus was tested for its ability to promote the growth of cucumber plants in a pot experiment. Cucumber seeds were sown in sterilised field soil amended with wheat grain inoculum (WGI) of PPA 1 at the rate of 0.5, 1 and 1.5% w/w, and plants were grown for 21 days in a net house. The treatment with PPA1 significantly increased shoot length, shoot fresh weight, shoot dry weight, root length, root fresh weight, root dry weight, plant length, leaf area and leaf chlorophyll content of cucumber plants compared to non-treated control. The growth promotion rate increased with the increasing concentration of inoculum of PPA1 applied to the soil. The fungus was re-isolated from the roots of cucumber plants at higher frequencies. These results suggest that Aspergillus spp. PPA1 is a root colonising plant-growth promoting fungus for cucumber. 相似文献
142.
Differentiation of Listeria monocytogenes and Listeria innocua by 16S rRNA genes and intraspecies discrimination of Listeria monocytogenes strains by random amplified polymorphic DNA polymorphisms. 总被引:7,自引:5,他引:7
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J Czajka N Bsat M Piani W Russ K Sultana M Wiedmann R Whitaker C A Batt 《Applied microbiology》1993,59(1):304-308
Differences in the 16S rRNA genes (16S rDNA) which can be used to discriminate Listeria monocytogenes from Listeria innocua have been detected. The 16S rDNA were amplified by polymerase chain reaction with a set of oligonucleotide primers which flank a 1.5-kb fragment. Sequence differences were observed in the V2 region of the 16S rDNA both between L. monocytogenes Scott A and L. innocua and between different L. monocytogenes serotypes. Although L. monocytogenes SLCC2371 had the same V2 region sequence as L. innocua, the two species were different within the V9 region at nucleotides 1259 and 1292, in agreement with previous studies (R.-F. Wang, W.-W. Cao, and M.G. Johnson, Appl. Environ. Microbiol. 57:3666-3670, 1991). Intraspecies discrimination of L. monocytogenes strains was achieved by using the patterns generated by random amplified polymorphic DNA primers. Although some distinction can be made within the L. monocytogenes species by their 16S rDNA sequence, a far greater discrimination within species could be made by generating random amplified polymorphic DNA patterns from chromosomal DNA. By using a number of 10-bp primers, unique patterns for each isolate which in all cases examined differentiate between various L. monocytogenes serotypes, even though they may have the same 16S rRNA sequences, could be generated. 相似文献
143.
Bilal Hussain Tayyaba Sultana Salma Sultana N. Al-Mulhim Shahid Mahboob 《Saudi Journal of Biological Sciences》2018,25(7):1326-1331
This study’s objective was to assess a seasonal impact of industrial and sewage waste disposal on water quality of the river upstream Trimu Head. Considering the significance of the river, drain wastewater was analyzed during the summer and the winter seasons from pre-determined locations. Water quality parameters were recorded higher than the maximum permissible limits prescribed by WHO for freshwater bodies. Level of these Physio-chemical variables was higher in the winter due to the least amount of water from domestic sewage. Although some of these parameters indicated sedimentation hitherto the water quality of River Chenab was found very poor due to the pollution bestowed by tributary waste water from drains. Findings of this investigation suggest the importance of continuous monitoring and assessment to improve the water quality of the river. This study provides a baseline data which may be compared to assess any further deterioration in the water quality and may also be used to plan future monitoring and required restoration of habitat for the safe supply of fish to the population of this region. 相似文献
144.
Nazmun Nahar Rebeca Sultana Emily S. Gurley M. Jahangir Hossain Stephen P. Luby 《EcoHealth》2010,7(2):196-203
Nipah virus (NiV) infection is a seasonal disease in Bangladesh that coincides with the date palm sap collection season. Raw
date palm sap is a delicacy to drink in Bengali culture. If fruit bats that are infected with NiV gain access to the sap for
drinking, they might occasionally contaminate the sap through saliva and urine. In February 2007, we conducted a qualitative
study in six villages, interviewing 27 date palm sap collectors (gachhis) within the geographical area where NiV outbreaks have occurred since 2001. Gachhis reported that bats pose a challenge to successful collection of quality sap, because bats drink and defecate into the sap
which markedly reduces its value. They know some methods to prevent access by bats and other pests but do not use them consistently,
because of lack of time and resources. Further studies to explore the effectiveness of these methods and to motivate gachhis to invest their time and money to use them could reduce the risk of human Nipah infection in Bangladesh. 相似文献
145.
In pea, maize and tomato plants a hitherto undescribed L-tryptophan dehydrogenase activity (TDH) has been detected. This enzyme
catalyzes the reversible formation of indolepyruvic acid (IPyA) from L-tryptophan (L-trp). TDH and L-glutamate dehydrogenase
(GDH), related enzymes in their mode of action, could be separated by gel chromatography. Enzymatic activity of TDH was sustained
by both pyridine coenzymes NAD/NADP. With pea TDH the coenzyme NAD displays, at optimum pH 8.5 and at room temperature, only
about 40-70 % of the activity of NADP. The amination of IPyA is catalysed more actively than the deamination of L-trp. L-trp/IPyA,
L-glu/ketoglutarate, L-ala/pyruvate reacted as dehydrogenase substrates; L-phe/ phenylpyruvate, D-trp and D-phe did not react
with pea enzyme extracts. A considerable similarity between the active centres of TDH and GDH has been found using inhibitors:
absence of heavy metals, presence of a carbonyl group, indispensibility of bivalent ions for the enzyme activity. Pea TDH
and GDH were distinctly inhibited by sodium azide. For the activity of TDH the presence of SH groups is less important than
for GDH. The TDH activity in the investigated plants was lower than the GDH activity. The possible role of TDH in the regulation
of the IPyA pool is discussed.Doc. RNDr. PhMr. M. Kutáček died on 28 November, 1989. The final form for print was prepared by dr. Ivana Machdckovd of the
same Institute, who will also answer the reprint requests. Received June 6, 1990; accepted October 10, 1990 相似文献
146.
Maurice Shamma Vassil St. Georgiev Ghulam A. Miana F.Sultana Khan 《Phytochemistry》1973,12(8):2051-2054
Three new steroidal alkaloids have been obtained from Buxus papillosa Schneider. These are (?)-cyclobuxupaline-C (IV)(+)-cyclopapilosine-D (VII) and (+)-buxamine-C (IX). A known alkaloid also present is desoxy-16-buxidienine (X). 相似文献
147.
Jahangir T Khan TH Prasad L Sultana S 《Redox report : communications in free radical research》2005,10(6):303-310
Farnesol is an isoprenoid found in essential oils of ambrette seeds, citronella and in various aromatic plants. Exposure to cadmium from various sources affects the renal system adversely and Cd is an established genotoxic agent. In the present study, we evaluated the antigenotoxic and antioxidant efficacy of farnesol against cadmium chloride (CdCl2)-induced renal oxidative stress and genotoxicity in Swiss albino mice. Single, intraperitoneal doses of CdCl2(5 mg/kg body weight) for 24 h resulted in a significant (P < 0.001) increase in chromosomal aberration and micronuclei formation. The oral administration of farnesol at two doses (1% and 2% per kg body weight) for seven consecutive days showed significant (P < 0.05) suppression of the genotoxic effects of CdCl2 in the modulator groups. To study the mechanism by which farnesol exerts its antigenotoxic potential, enzymes involved in metabolism and detoxification were estimated. CdCl2 intoxication adversely affected the renal antioxidant armory and increased TBARS formation and xanthine oxidase levels significantly (P < 0.001). Farnesol showed a significant (P < 0.001) recovery in antioxidant status viz, GSH content (and its dependent enzymes) and catalase activity. Farnesol pretreatment in CdCl2-intoxicated mice showed marked (P < 0.001) suppression of TBARS' formation and XO activity. Our results support the conclusion that the anticlastogenic effect of farnesol could be due to restoration of antioxidants and inhibition of oxidative damage. 相似文献
148.
Yasumasu S Mao KM Sultana F Sakaguchi H Yoshizaki N 《Development genes and evolution》2005,215(10):489-498
The aim of the present study was to reveal molecular entities participating in the digestion of the egg envelope in the Japanese
quail, Coturnix japonica. We isolated a 1,510-bp cDNA from extraembryonic tissues of developing embryos and designated it quail hatching enzyme (QHE)
cDNA. The QHE cDNA was found to code a protein molecule comprising an astacin protease domain in the N-terminal half and a
complement subcomponents C1r/C1s, Uegf, Bmp1 (CUB) domain in the C-terminal half. A phylogenetic analysis showed that QHE
belonged to the hatching enzyme group and was distinct from other proteases in the astacin family. Northern blotting and in
situ hybridization demonstrated that expression of the QHE mRNA occurred twice during the development: first in ectodermal
cells of the yolk sac on days 0–5, then in those of the albumen sac on days 8–13. Zymography revealed that proteolytic activity
in extracts of days 3–4 and 9–12 embryos appeared at the position of 40 kDa. Immunoblotting tests showed that anti-QHE antiserum
stained a 40-kDa molecule in extracts of day 3 area vitellina. Anti-QHE antibody stained the ectodermal cells of the area
opaca on days 0–1, those of the area vitellina of the yolk sac on days 2–5, and those of the albumen sac on days 9–12. The
temporal and spatial expression pattern of QHE mRNA was closely associated with digestion of the vitelline membrane occurring
on days 1–4, and with that of the egg white on days 9–12. 相似文献
149.
Ross SA ElSohly MA Sultana GN Mehmedic Z Hossain CF Chandra S 《Phytochemical analysis : PCA》2005,16(1):45-48
Chemical investigation of the pollen grain collected from male plants of Cannabis sativa L. resulted in the isolation for the first time of two flavonol glycosides from the methanol extract, and the identification of 16 cannabinoids in the hexane extract. The two glycosides were identified as kaempferol 3-O-sophoroside and quercetin 3-O-sophoroside by spectroscopic methods including high-field two-dimensional NMR experiments. The characterisation of each cannabinoid was performed by GC-FID and GC-MS analyses and by comparison with both available reference cannabinoids and reported data. The identified cannabinoids were delta9-tetrahydrocannabiorcol, cannabidivarin, cannabicitran, delta9-tetrahydrocannabivarin, cannabicyclol, cannabidiol, cannabichromene, delta9-tetrahydrocannabinol, cannabigerol, cannabinol, dihydrocannabinol, cannabielsoin, 6a, 7, 10a-trihydroxytetrahydrocannabinol, 9, 10-epoxycannabitriol, 10-O-ethylcannabitriol, and 7, 8-dehydro-10-O-ethylcannabitriol. 相似文献
150.
Ferric nitrilotriacetate (Fe-NTA) is a well-known renal carcinogen. In this communication, we show the chemopreventive effect of Ficus racemosa extract against Fe-NTA-induced renal oxidative stress, hyperproliferative response and renal carcinogenesis in rats. Fe-NTA (9 mg Fe/kg body weight, intraperitoneally) enhances renal lipid peroxidation, xanthine oxidase, gamma-glutamyl transpeptidase and hydrogen peroxide (H(2)O(2)) generation with reduction in renal glutathione content, antioxidant enzymes, viz., glutathione peroxidase, glutathione reductase, catalase, glucose-6-phosphate dehydrogenase and phase-II metabolising enzymes such as glutathione-S-transferase and quinone reductase. It also enhances blood urea nitrogen, serum creatinine, ornithine decarboxylase (ODC) activity and thymidine [(3)H] incorporation into renal DNA. It also enhances DEN (N-diethylnitrosamine) initiated renal carcinogenesis by increasing the percentage incidence of tumors. Treatment of rats orally with F. racemosa extract (200 and 400 mg/kg body weight) resulted in significant decrease in gamma-glutamyl transpeptidase, lipid peroxidation, xanthine oxidase, H(2)O(2) generation, blood urea nitrogen, serum creatinine, renal ODC activity, DNA synthesis (P<0.001) and incidence of tumors. Renal glutathione content (P<0.01), glutathione metabolizing enzymes (P<0.001) and antioxidant enzymes were also recovered to significant level (P<0.001). Thus, our data suggests that F. racemosa extract is a potent chemopreventive agent and suppresses Fe-NTA-induced renal carcinogenesis and oxidative damage response in Wistar rats. 相似文献