Irshad Ahmad

Phytochemical composition and pharmacological prospectus of Ficus bengalensis Linn. (Moraceae)- A review

Ficus bengalensis Linn (Moraceae) is a plant that is widely distributed in India. To the Hindus it is sacred and worshipped with special prayers on Vata Sawitri day. In traditional medicines it is used for healing obstruction of urine flow, diarrhea, dysentery, conjunctivitis, scabies and diabetes. So it has been a subject of chemical, biological and pharmacological interest since a long time. Its chemical investigation shows that it contains Bengalenosides that is, glycosides or flavonoids, ketones, flavonols, pentacyclic triterpenes and triterpenoids, coumarin, sterols, tiglic acid esters, alpha-Dglucose and meso-inositol. The aqueous or alcoholic extracts of various parts of this plant were found to have various pharmacological activities for example, antidiabetic, hypocholesterolemic, hypolipidemic, anti-inflammatory, anthelmintic, antibacterial, antiallergic and anti-tumor activity. In this review, we have investigated the pharmacological activities of F. bengalensis Linn (Moraceae) and discussed its various chemical constituents that may be responsible for these multi-aspect activity spectrums of this plant.

Antifungal and antispasmodic activities of the extracts of Euphorbia granulata

The dichloromethane and methanolic extracts of the plant Euphorbia granulata were investigated for their antifungal, antibacterial, phytotoxic, brine-shrimp cytotoxic, antioxidant, spasmolytic (antispasmodic) and acetylcholinestrase inhibitory activities. The dichloromethane extract showed strong inhibition against Microsporum canis (90%) and against Aspergillus flavus (50%). Both the extracts inhibited the spontaneous contractions in rabbit jejunum preparations with EC50 value of 0.17 and 1.3 mg/mL, respectively and also relaxed the K + -induced contractions with EC50 0.2 and 2.8 mg/mL, respectively, suggesting a calcium channel blocking activity. However, the extracts did not show antibacterial, phytotoxic, brine-shrimp cytotoxic, antioxidant and acetylcholinestrase inhibitory activities.

Overcoming challenges for amplified expression of recombinant proteins using Escherichia coli

A thorough characterisation of the genetics, physiology and metabolism of Escherichia coli has led to the availability of a large number of strains and vectors suitable for recombinant protein expression. Despite the relative ease in using E. coli for achieving amplified expression of many recombinant proteins, for some proteins this can be a frustrating and time-consuming process leading to very low expression or no expression at all. This is especially true for membrane proteins, which introduce additional challenges. A number of factors can be considered and optimised for achieving required levels of amplified expression of recombinant proteins in E. coli that are broadly classified as host strain, expression vector and growth conditions. In this paper we summarise these factors and consolidate the common challenges encountered and approaches to overcome them, focusing in particular on cases where there is low amplified expression or no expression at all of the desired recombinant protein, due to various reasons.

Synthesis, Structural Elucidation, and Antibacterial Evaluation of Some New Molecules Derived from Coumarin, 1,3,4-Oxadiazole, and Acetamide

Because of the reported biological activities of coumarin, 1,3,4-oxadiazole, and acetamides, some new compounds incorporating these moieties were synthesized and evaluated for their biological potential against Gram-positive and Gram-negative bacteria. In the present work, 4-chlororesorcinol (1) and ethyl acetoacetate (2) were mixed in a strong acidic medium to synthesize 6-chloro-7-hydroxy-4-methyl-2-oxo-2H-chromene (3) which was subjected to the intermolecular cyclization after consecutive three steps to synthesize 5-(6-chloro-4-methyl-2-oxo-2H-chromen-7-yl)oxy]-1,3,4-oxadiazol-2-thiol (6). A series of acetamoyl electrophiles, 8a–o, were synthesized from aralkyl/alkyl/aryl amines, 7a–o, in an aqueous basic medium. The final compounds, 9a–o, were synthesized by the reaction of compounds 6 and 8a–o in DMF/NaH. The synthesized compounds were structurally elucidated by spectral data analysis of IR, 1H-NMR, and EIMS. The most of the synthesized compounds remained moderate to excellent antibacterial agents. The molecules, 9e, 9j, and 9k, were the most efficient ones against all the five bacterial strains taken into account.

Monograph of Tribulus terrestris

Tribulus terrestris has long been used as a tonic and aphrodisiac, and a diuretic in Unani system of medicine. The diuretic effect was attributed to the presence of potassium salts in high concentration. So many studies have been done on pharmacological activities of T. terrestris. The major constituents of these plants are steroidal saponins namely: terrestrosins A, B, C, D and E, desgalactotigonis, Fgitonis, desglucolanatigoneis, gitnin etc. The biological activity exhibited by saponins include: pisicidal, antimicrobial, molluscicidal, haemolytic, antiviral, cytotoxic, antihepatotoxic, spermicidal, insecticidal, antioedematous, antiulcer analgesic, immunomodulatory, and sedative effects.

Pacing across the membrane: the novel PACE family of efflux pumps is widespread in Gram-negative pathogens

The proteobacterial antimicrobial compound efflux (PACE) family of transport proteins was only recently described. PACE family transport proteins can confer resistance to a range of biocides used as disinfectants and antiseptics, and are encoded by many important Gram-negative human pathogens. However, we are only just beginning to appreciate the range of functions and the mechanism(s) of transport operating in these proteins. Genes encoding PACE family proteins are typically conserved in the core genomes of bacterial species rather than on recently acquired mobile genetic elements, suggesting that they confer important core functions in addition to biocide resistance. Three-dimensional structural information is not yet available for PACE family proteins. However, PACE proteins have several very highly conserved amino acid sequence motifs that are likely to be important for substrate transport. PACE proteins also display strong amino acid sequence conservation between their N— and C-terminal halves, suggesting that they evolved by duplication of an ancestral protein comprised of two transmembrane helices. In light of their drug resistance functions in Gram-negative pathogens, PACE proteins should be the subject of detailed future investigation.

Ridge-furrow mulched with plastic film improves the anti-oxidative defence system and photosynthesis in leaves of winter wheat under deficit irrigation

In semi-arid areas of China, the ridge-furrow mulched with plastic film (RF) cultivation system is a common water-saving agricultural technique where the shortage of water resources has become a serious problem. Therefore, we aimed to explore whether this cultivation is actually an improvement over the traditional flat planting (TF) method while testing two deficit irrigation (150, 75 mm) levels to grow winter wheat. Furthermore, we examined the responses of the anti-oxidative defence system and photosynthetic capacity of winter wheat flag leaves under three simulated rainfall (275, 200 and 125 mm) conditions. The results showed that the RF system with 150 mm deficit irrigation and 200 mm simulated rainfall condition (RF2150) treatment raised soil water content (%) at the jointing and flowering stages and achieved higher net photosynthesis rates (Pn) in flag leaves. Furthermore, such improvements were due to the reduction of malondialdehyde (MDA) content and oxidative damage during different growth stages of winter wheat. The RF2150 treatment significantly increased the activities of superoxide dismutase (SOD); peroxidise (POD), catalase (CAT) and ascorbate peroxidase (APX) and the content of soluble protein (SP) during different growth stages of winter wheat. Furthermore, RF2150 treatment attained the highest value at the flowering stage, while also exhibiting significant declines in contents of proline, MDA, H2O2 and O2 in flag leaves. The higher free H2O2 and O2 scavenging capacity and better anti-oxidative enzyme activities under the RF2150 treatment were due to the lower level of lipid peroxidation, which effectively protected the photosynthetic machinery. The net photosynthetic rate of flag leaves was positively correlated with SOD, POD, CAT, APX and SP activities, and negatively correlated with proline, MDA, H2O2 and O2 contents. We concluded that the RF2150 treatment was the better water-saving management strategy because it significantly delayed flag leaf senescence and caused the increases in SWC, WUE, Pn, antioxidant enzyme activities and grain yield of winter wheat grown in semi-arid regions of China.

Incidence and Drug Resistance of Zoonotic Mycobacterium bovis Infection in Peshawar, Pakistan

Prevalence of zoonotic Mycobacterium bovis (bTB) disease in human population is underreported from the North of Pakistan. Here, we report on the proportion of human bTB disease among the overall TB patients, drug resistance pattern of bTB isolates, and knowledge, attitude, and practices (KAP)-based analysis of bTB disease. For this purpose, sputum samples from a total of 300 clinically diagnosed TB patients and 100 randomly selected school children suspected of pulmonary TB were processed by culture as well as polymerase chain reaction (PCR) for isolation, identification, and confirmation of Mycobacterium tuberculosis (mTB) and bTB species. Isolates of bTB were processed for drug susceptibility tests. Data on KAP regarding TB were obtained on a pretested questionnaire. Sputum-based PCR results indicated that 288/300 (96%) were confirmed as mTB, while 12/300 (4%) were found as bTB diseases. Interestingly, none of the school child was declared positive for either mTB or bTB. Notably, 274/300 (91.3%) positively cultured samples were identified as mTB, 13/300 (4.3%) as bTB, while 5/300 (1.7%) as mixed containing both. Importantly, except one, all of the bTB isolates were found resistant to pyrazinamide. Surprisingly, most of the bTB isolates (~70%) were found resistant to a broad range of first- and second-line anti-TB drugs. SplitsTree and recombination analysis indicated no evidence of intergenic recombination. Finally, residence, occupation, presence of animals at home, and sleeping alongside animals were found significantly associated with occurrence of bTB disease. To the best of our knowledge, we report for the first time on the high (4%) burden of bTB disease in human TB patients in Peshawar, Pakistan.

Prevalence, quantification and isolation of pathogenic shiga toxin Escherichia coli O157:H7 along the production and supply chain of pork around Hubei Province of China

Shiga toxin Escherichia coli (STEC) O157:H7 is an important zoonotic food borne pathogen causing gastroenteritis that may lead to life threatening hemorragic colitis (HC) and hemorrhagic uremic syndrome (HUS). 325 meat and tissue samples were tested for enumeration of O157:H7 strains using most probable number (MPN)-PCR targeting their specific genes flicH7 and rfbO157 followed by isolation, sereotyping and pathogenicity testing. The overall prevalence of O157:H7 was 41.3% (134/325) along the production and supply chain of pork (PSCP), being higher in supply chain (59%, 118/200) as compared to pig farms (12.8%, 16/125). Along the PSCP, the highest prevalence was found in slaughter houses (86.25%, 69/80) followed by wet- (53.3%, 32/60) and super-markets (28.3%, 17/60). The MPN values ranged from 3 to 1100 MPN/g in overall positive samples, being higher in slaughter houses followed by wet and super markets. Except from intestine and meat samples of slaughter house, the MPN was found higher in summer as compared to winter samples. Eight STEC O157:H7 isolated from meat and liver samples were tested in Balb/C mice for pathogenicity. After development of clinical signs and symptoms, 50-83.3% mortality was produced in the infected mice. Histopathological investigations revealed visible necrosis of intestinal epithelial cells, shedding of cellular debris in the intestine, while in the kidney, necrosis of renal cortical portion of tubular epithelial cells was observed. STEC O157:H7 is prevalent along PSCP around Hubei of China in different proportions being alarmingly higher in supply chain and markets which is a matter of concern for public health.

Response of Maize Cultivars to Various Nitrogen Levels

Studies pertaining to the effect of different nitrogen rates n on the yield and yield components of maize cultivars (Azam n and Jalal), was conducted at the New Developmental Form n of The University of Agriculture Peshawar, during summer n 2011 using Randomized Complete Block Design (RCBD) with n split plot arrangement. The treatments comprised 0, 30, 60, n 90, 120, 150, 180 and 210 kgNha-1 assigned to main plot n and maize cultivars (Azam and Jalal) to sub plots. Results n revealed that maximum grain ear-1 (383.2), grain yield n (3747.41 kgha-1) and harvest index (27.66%) were recorded n in Azam cultivar. However maximum ear length (16.33 cm), n biological yield (14250 kgha-1) and thousand grain weight n (258.65 g) were observed in Jalal cultivar. Maximum n biological yield (16277.78 kg ha-1) was recorded with the n application of 180-210 kgNha-1. However maximum ear n length (17.18 cm), grain ear-1 (411.32), grain yield (4888.9 n kgha-1) and thousand grain weight (264.96 g) were observed n with the application of 180kgNha-1.