Center of Biotechnology and Microbiology

AIm: To study the clinicopathological aspects of primary CNS lymphoma in immunocompetent patients. mAterIAl and methOds: Sixteen patients with primary CNS lymphoma were analyzed for their clinico-pathological characteristics and followed-up for the treatment and subsequent management in Neurosurgery, and Medical and Radiation Oncology. results: The fronto-parietal region was the commonest location of CNS lymphoma; four cases of cerebellar lymphoma were seen. Our patients were relatively young with a mean age of 48 years and an age range of 35-60 years. Females outnumbered males with a ratio of 2.7:1. The commonest presentation was focal neurological-deficits and features of raised intracranial pressure. All the patients histologically had diffuse large B-cell lymphoma. Radiologically, most presented as disc-enhancing lesions. Two patients had multiple lesions. Most of the patients (10) died within a mean of 4.4 months (range 2 weeks-16 months). COnClusIOn: Primary CNS lymphoma is seen in immunocompetent patients as well. Relapse is common after treatment and the overall prognosis is unfavorable.

Ochratoxin A (OTA) is a potential nephrotoxic, teratogenic, immunogenic, hepatotoxic and carcinogenic mycotoxin, produced by Aspergillus westerdijkiae NRRL 3174. Herein we describe the characterization of a putative OTA-polyketide synthase gene “aoks1”, cloned by using gene walking approach. The predicted amino acid sequence of the 2 kb clone display 34–60% similarities to different polyketide synthase genes including lovastatine biosynthesis gene “lovb” in A. terreus, compactin biosynthesis gene “mlcA” in Penicillium citrinum and OTA biosynthesis gene “otapksPN” in P. nordicum. Based on the reverse transcription PCR and kinetic secondary metabolites production studies, aoks1 expression was found to be associated with OTA biosynthesis. Further a mutant, in which the aoks1 gene was inactivated by Escherichia coli hygromycin B phosphotransferase gene, lost the capacity to produce OTA, but still producing mellein. To our knowledge this report describes for the first time characterization of a gene involved in OTA biosynthesis, with the information about mellein which was proposed in the literature to be an intermediate OTA. This study also suggests that aoks1 may be the second polyketide synthase gene required for OTA biosynthesis in A. westerdijkiae NRRL 3174.

In phytopathogenic fungi, STE12-like genes encode transcription factors essential for appressorium-mediated host penetration. However, their regulation and downstream targets are still unknown. In the present study, a STE12-like gene (CLSTE12) from Colletotrichum lindemuthianum was isolated. We identified a spliced variant whose expression was negatively regulated during early stages of pathogenesis, whereas the correctly spliced mRNA remained expressed up to the penetration step, suggesting distinct roles for these two transcripts. Indeed, the full-length sequence was able to complement a yeast STE12 mutant, whereas overexpression of the transcript variant had a dominant-negative effect on yeast invasive growth and C. lindemuthianum pathogenicity. To further investigate the downstream genes that could be regulated by CLSTE12, disruption mutants were generated. Phenotypic analyses of the mutants revealed reduced pectinase activity and conidial adhesion to polystyrene. Analysis of cell surface proteins allowed the identification of a major protein, Clsp1p, which was absent from the mutants. Clsp1p belongs to a new family of wall-associated proteins only found in euascomycetous fungi. Overall, these results suggest that the activity of CLSTE12 can be modulated by a regulated alternative splicing mechanism and that this factor is involved in the production of cell surface proteins and host cell wall degrading enzymes.

Aspergillus westerdijkiae is the main producer of several biologically active polyketide metabolites including isoasperlactone and asperlactone. A 5298 bp polyketide synthase gene “aomsas” has been cloned in Aspergillus westerdijkiae by using gene walking approach and RACE-PCR. The predicted amino acid sequence of aomsas shows an identity of 40–56% with different methylsalicylic acid synthase genes found in Byssochlamys nivea, P. patulum, A. terreus and Streptomyces viridochromogenes. Based on the reverse transcription PCR and kinetic secondary metabolites production studies, aomsas expression was found to be associated with the biosynthesis of isoasperlactone and asperlactone. Moreover an aomsas knockout mutant “aoΔmsas” of A. westerdijkiae, not only lost the capacity to produce isoasperlactone and asperlactone, but also 6-methylsalicylic acid. The genetically complemented mutant ao+msas restored the biosynthesis of all the missing metabolites. Chemical complementation through the addition of 6-methylsalicylic acid, aspyrone and diepoxide to growing culture of aoΔmsas mutant revealed that these compounds play intermediate roles in the biosynthesis of asperlactone and isoasperlactone.

Background Hepatitis C Virus (HCV) genotypes frequency is important for the predication of response to therapy and duration of treatment. Despite variable response rates experienced in the case of Interferon (IFN) -based therapies, there was scarcity of data on HCV genotypes frequency in Khyber Pakhtunkhwa (KPK). Study Design A total of 200 blood samples were collected from chronic HCV patients prior to the initiation of anti-viral therapy. The study population included patients from 6 districts of KPK. Active HCV infection was confirmed in case of all the patients by real time PCR. HCV genotypes were determined in each case by Type-specific PCR. Results The analysis revealed that out of 200 PCR positive samples; 78 (39%) were 2a, 62 (31%) were 3a, 16 (8%) were 3b, 34 (17%) were untypable while 1a, 2b and 1b were 3 (1.5%), 2 (1%) and 5 (2.5%), respectively. Conclusion Genotype determination is not carried out prior to therapy in KPK. Although, the abundantly prevalent types (2a and 3a) of HCV in KPK are susceptible to combination therapy, yet resistance experienced in some of the chronic HCV patients may partly be attributed to the prevalence of less prevalent resistant genotypes (1a, 1b) of HCV among the population.

Background Myrsine africana is an herbaceous plant that is traditionally used as appetizer and carminative. Locally, it is used for the treatment of pulmonary tuberculosis, rheumatism and diarrhea by healers. The aims of the current study were to screen the crude methanol extract obtained from the aerial parts (leaves and stem) of M. africana, for antispasmodic actions on isolated tissues and further to subject the ethyl acetate (EtOAc) fraction of plant to column chromatography for isolation of pure compounds. Methods The antispasmodic action of the crude methanol extract was measured on the spontaneous rabbit's jejunum preparations at concentration 0.01, 0.03, 0.1, 0.3, 1.0, 5.0 and 10.0 mg/ml. The crude extract was also applied, in similar concentrations, on KCl (80 mM) induced contractions to explain its possible mode of action. Results A new compound Myrsigenin was isolated from the EtOAc fraction of M. africana. The structure of the compound was identified with the help of 13C-NMR, 1H-NMR, HMBC, HMQC, NOESY and COSY. The plant crude methanol extract showed a significant antispasmodic action on rabbit jejunum and abolished the tissue contraction completely at concentration of 5.0 mg/ml. Conclusion The study concludes that the methanol crude extract of aerial parts of M. africana has antispasmodic action possibly through the calcium channel blocking mechanisms. A new compound Myrsigenin was isolated from the EtOAc fraction of the plant.

The crude methanolic extract and various fractions derived from the aerial parts of Myrsine africana were screened in vitro for possible insecticidal, antifungal, brine shrimp lethality and nitric oxide free radical scavenging activities. Low insecticidal activity (20 %) was shown by chloroform (CHCl 3 ) and aqueous fractions against Tribolium castaneum and Rhizopertha dominica, respectively. Good cytotoxic activity (66.66 %) was shown by the n-hexane fraction of the plant at 1000 g/ml. The rest of the fractions showed low lethality at higher doses. No antifungal activity was observed for the crude extract and fractions screened against various fungal strains. The plant crude extract and fractions showed a concentration dependent nitric oxide free radical scavenging activity.

Keeping in view this idea, the crude methanolic extract and various fractions of Zizyphus jujuba were screened for antibacterial, phytotoxic and haemagglutination activities. The n-hexane and aqueous fractions showed significant activity of 60 and 66.66% against Bacillus pumalis and Pseudomonas aerugenosa, respectively. Activity of ethyl acetate fraction was 65.38, 62.96, 62.96 and 72% against Staphylococcus epidermidis, Salmonella typhi, P. aerugenosa and B. pumalis, respectively. On the contrary, no activity of this fraction was recorded against Streptococcus pneumoniae. The crude, nhexane, chloroform, ethyl acetate and aqueous fractions showed 41.37, 44.82, 41.37, 55.17 and 44.82% activity against Enterobacter aerogenes, respectively. The crude methanolic extract and n-hexane fractions were inactive against Escherichia coli, S. pneumoniae and Klebsella pneumoniae, respectively. The ethyl acetate fraction was moderately phytotoxic against Lemna minor L at 1000 µg/ml. All the other fractions showed low phytotoxic activity at 1000 µg/ml. At 100 µg/ml, all the fractions showed low phytotoxic activity except crude methanolic extract, which was inactive. All the test samples were inactive at 10 µg/ml. All dilutions of the test samples showed no haemagglutination activity against any blood group.

African Journal of Biotechnology Vol. 9(53), pp. 9063-9069, 27 December, 2010 Available online at http://www.academicjournals.org/AJB ISSN 1684–5315 ©2010 Academic Journals ... Biological activities of a new compound isolated from ... Bashir Ahmad1*, Sadiq Azam1, Shumaila ...

The crude methanolic extract and various fractions derived from the aerial parts of Myrsine africana were screened in vitro for possible phytotoxic, antibacterial and haemagglutination activities. Moderate phytotoxic activity (31.25 %) was observed against Lemna minor L at 1000 ...

The antibacterial, antifungal and insecticidal activities of the crude extract of Polygonum persicaria, Rumex hastatus, Rumex dentatus, Rumex nepalensis, Polygonum plebejum and Rheum australe have been studied. Six bacterial species were used, of which Citrobacter frundii, Escherichia coli, Enterobacter aerogenes and Staphylococcus aureus were the most susceptible bacterial species to crude extract with MICs 16, 5.0, 25 and 0.156 µ µ µ µg/ml, respectively. Among the tested fungal species Fusarium solani, Aspergillus flavus and Aspergillus niger were more susceptible to crude extracts with MICs 0.75, 2.15, and 1.75 µg/ml, respectively. The crude extracts of R. dentatus and R. nepalensis show significant insecticidal activity against Sitophilus oryzae; P. persicaria and P. plebejum show significant insecticidal activities against Tribolium castaneum, respectively. The above selected plants were shown by in vitro assays to be a potential source for natural antifungal, antibacterial and insecticidal agents.

Plants or their parts are used as folk medicines in many parts of the world to cure various infectious diseases such as bronchitis, urinary tract infections, diarrhea, cutaneous abscesses and parasitic diseases. The crude methanolic extract and various fractions of the aerial parts of Acacia modesta were screened for haemagglutination, antibacterial and phytotoxic insecticidal activities. The crude methanolic extract of the plant showed weak haemagglutination activity against A +ive , B -ive and O +ive at dilution of 1:2. The ethyl acetate (EtOAc) fraction showed weak activity against B -ive , A -ive and O +ive at dilution of 1:2. The n-hexane and EtOAc fractions showed good antibacterial activity against Klebsiella pneumoniae (66.66 %) and (61.90%), respectively. All the fractions showed moderate activity against Escherichia coli except chloroform (CHCl 3 ). Aqueous fraction showed no activity against Streptococcus pneumoniae. Low phytotoxic activity was shown by the test samples at concentration of 1000 and100 µg/ml against Lemna minor L. At 10 µg/ml, no phytotoxic activity was shown by the test samples. The nhexane fraction showed good (60%), EtOAc and aqueous fractions, low (20%), while the crude methanolic extract and CHCl 3 fractions were inactive against Callosbruchus analis.

Many bioactive compounds are produced by the medicinal plants that have important pharmacological activities. The present study describes the chemical composition, antifungal, phytotoxic, brine shrimp cytotoxic, insecticidal and antibacterial activities of essential oils from Acacia modesta. The oils were extracted from the n-hexane fraction of the aerial parts of the plant and were analyzed by gas chromatograph and mass spectrometer (GC-MS). The results revealed 38 components from the oil of A. modesta. The oils exhibited moderate antifungal activity (40%) against Microsporum canis and low against Fusarium solani (25%). At the concentration of 1000 and 100 µg/ml, the oils showed moderate phytotoxic activity of 50 and 40%, respectively, against Lemna minor. The oils were highly cytotoxic at the concentration of 100 µg/ml killing all the shrimps in the experiment. At the concentration of 10 µg/ml only 2 and at concentration of 1 µg/ml, only 8 shrimps survived out of 30. The oils showed no antibacterial and insecticidal activity against the test organisms.

This study investigates the cytological and morphological differences of selected SH lines which reflect the genetic diversity in these alien wheat species. The studied SH lines showed considerable variation in agronomically important traits such as plant height, days to flowering, days to physiological maturity and 1000-grain weight etc. Cytological differences were also observed among the studied SH lines where some lines showed euploidy (normal number of mitotic chromosomes) while other showed aneuploidy (abnormal number of mitotic chromosomes). These results have implications for selecting the diverse SH lines which can revolutionize the yield and productivity after crossing with common bread wheat.

Background: Interferon based therapy is used to eradicate the Hepatitis C Virus from the bodies of the infected individuals. HCV is highly prevalent in Khyber Pakhtunkhwa (KPK) that is why it is important to determine the response of standard interferon based therapy in Chronic HCV patients of the region.

Onosma griffithii was screened for possible pharmacological activities. The crude methanolic extract (MeOH) and its fractions demonstrated parasiticidal activity (IC 50 (µg/ml ± S.D) = 31.03 ± 0.23) against Leishmania major. Based on the IC 50 values, the potency of the standard drug (Pentamidine) and test fractions were of the order as: Pentamidine > crude extract >

Plants are very useful, self-generating machines, producing a variety of useful bioactive products. Keeping in view this idea, the crude methanolic extract and various fractions of Zizyphus jujuba were screened for antifungal, cytotoxic, antitermite and insecticidal activities. Low activity was shown by the crude methanolic extract (12%), n-hexane (9%), chloroform (20%) and ethyl acetate (14%) fraction against Penicillium notatum. Low activity was shown by the n-hexane fraction against Aspergillus niger (10%) and Trichoderma harzianum (13%) and inactive against Aspergillus flavus, Fusarium oxysporum and Rhizopus stolonifer. The CHCl(3) fraction exhibited low activity of 10% against F. oxysporum while showing no activity against the rest of the test fungi. All the test samples were inactive against Rhizopus stolonifer. The crude methanolic extract was highly cytotoxic (73.33%) at the concentration of 1000 (µg/ml) while the rest of the test samples were low in toxicity at the same con...

human beings. Keeping this in mind, the crude methanolic extract and various fractions of Fumaria indica was screened for antibacterial, antifungal, phytotoxic and haemagglutination activities. The crude methanolic extract showed good activity against P. aerogenosa (77.8%), B. subtilus (66.7%) and low against S. aureus (38.5%) and E. coli (33.4%). The n-hexane fraction showed moderate activity against P. aerogenosa (40.7 %), CHCl3 fraction against S. aureus (53.8%), B. subtilus (51.9%). The aqueous fraction showed low activity against all test organisms i.e. P. aerogenosa (37%), S. aureus (26.9%), E. coli (22.3%) and B. subtilus (11.1%). The crude methanolic extract and various fractions of F. indica were inactive against all the test fungi i.e. A. niger, A. flavus, P. notatum, F. oxysporum, T. harzianum and A. alternata. The crude methanolic extract, n-hexane, CHCl3, EtOAc and aqueous fractions showed low phytotoxic activities of (26.7, 13.4 and 0%), (73.4, 33.4 and 20%), (26.7, 20...

Plants have been shown to possess a great potential to benefit mankind. Extracts from plants that have antiglycation and antioxidation abilities can be of great therapeutic value in reducing complication of diabetes and slowing down aging. Advanced glycation end-products (AGE's) formation due to non-enzymatic glycation and oxidative stress has been demonstrated in the pathogenesis of diabetic complications and aging processes. In this study we investigated the antiglycation and antioxidation potential of methanolic extracts of Berberis lyceum and Terminalia chebula. Results indicated that the methanolic extract of B. lyceum had more antiglycation ability with a Minimum inhibitory concentration (MIC 50) of 123 µg/mL as compared to the MIC 50 of 110 µg/ml of T. chebula. While the results of antioxidation assay showed that T. chebula has more antioxidation potential than B. lyceum. T. chebula had 46.55, 35.01 and 32.81% antioxidation potential at 0.5 mg, 0.25 mg and 0.125 mg respec...