Gram-negative bacteria were collected from different clinical labs situated in Karachi. Of these 83 isolates, 99% were found resistant against one or more of the following antibiotics: ampicillin, co-amoxiclav, gentamycin, neomycin, streptomycin and tetracycline. Most of the isolates were multi-drug resistant (MDR) having resistance to three or more antibiotics at a time. For ampicillin, 4.8% of the isolates were found Susceptible, 3.6% were Intermediate while 91.5% were found Resistant. For co-amoxiclav, 1.2% of the isolates were found Susceptible, 6% were Intermediate while 92.7% were found Resistant. For gentamicin, 3.6% of the isolates were found Susceptible, 10.8% were Intermediate while 86.7% were found Resistant. For neomycin, 21.6% of the isolates were found Susceptible, 40.9% were Intermediate while 43.4% were found Resistant. For streptomycin, 1.2% of the isolates were found Susceptible, 18% were Intermediate while 91.6% were found Resistant. For tetracycline, 15.7% of the isolates were found Susceptible, 45.7% were Intermediate while 53% were found Resistant. The study confirmed the presence of multidrug resistance in indigenous clinical gram-negative bacteria which is an alarming situation and needs development of effective alternative strategies for the treatment of infections.

This study explores the antioxidant activity, phytochemical screening, total phenolic and flavonoids contents in the extracts of four locally available weeds plants namely Convolvulus arvensis, Chenopodium murale, Avena fatua and Phalaris minor with different solvents. The antioxidant activities of these extracts were determined via various in-vitro methods such as total antioxidant activity (TAA), reducing power (RP), DPPH (2,2-Diphenyl-1-Picrylhydrazyl) free radical scavenging and hydrogen peroxide scavenging assays. Phytochemical screening was performed both qualitatively as well as quantitatively. Total phenolic content (TPC) and total flavonoid content (TFC) were determined through Folin- Ciocalteu reagent and aluminium chloride methods respectively. Methanol-chloroform solvent showed the presence of a high amount of TPC in milligram of gallic acid equivalent per gram of dry weight (mg of GAE/g of DW) in the extracts of all weeds. Their descending sequence was Avena fatua (74.09) ˃ Phalaris minor (65.66) ˃ Chenopodium murale (64.04) ˃ Convolvulus arvensis (61.905), while, chloroform solvent found to be best solvent for the extraction of TFC. Methanol-chloroform solvent was also found to be best solvent for TAA (Total antioxidant activity assay) which showed values in milligram of ascorbic acid equivalent per gram of dry weight (mg of AAE /g of DW), for DPPH scavenging activity, reducing power (antioxidant activity) and hydrogen peroxide scavenging activity. Phytochemical screening indicated the presence of polyphenols, flavonoids, tannins, saponins, alkaloids and glycosides in these weeds.

The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.

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Acid phosphatase isoenzyme (AcP-II) from leaves of germinating seeds of vigna radiata (mung beans) was partially purified by CM-Cellulose chromatoghraphy, gelfiltration on Ultrogel AcA 44 and Con A-Sepharose affinity chromatoghraphy. The specific activity of 25U/mg of protein was obtained with recovery of 4 %. The enzyme showed a purification by a factor of 86. Gel filtration experiment and sodium dodecyl sulphate polyacrylamide gel electrophoresis indicated that the isoenzyme had a molecular weight of 29 kDa. The K-m value of the isoenzyme was 0.5 mM with p-nitrophenyl phosphate as substrate. The enzyme had pH optimum of 5.5 and optimum temperature of 60 degrees C. The enzyme was inhibited by phosphate, vanadate, fluoride and molybdate. It was also strongly inhibited by Cu++, Hg++, Zn++ and Al+++. The enzyme had very little effect of inhibition by thiol specific reagents, such as iodoacetamide, N-ethylmaleimide etc., suggesting that no -SH groups are involved in the enzyme catalysis. Dithiothreitol and beta-mercaptoethanol had small activating effect at low concentrations indicating their properties as reducing agents but at their high concentrations, the activation was replaced by inhibition, suggesting that these thiols may cause a conformational change in the enzyme at a place other than the active site. Variation of K-m values with pH alteration study showed that a histidine may constitute a part of an active site. This was confirmed by inhibitory effect of high concentration of iodoacetate at pH 7.2