http://localhost:80/xmlui/handle/123456789/19292 2026-04-23T00:17:23Z http://localhost:80/xmlui/handle/123456789/19939 Title: Phytochemical Screening, Total Phenolic Contents and Biological Evaluation of Aerial Parts of Nepeta praetervisa Authors: Ghulam Fareed; Nighat Afza; Abdul Malik; Muhammad AliVersiani; Nazia Fareed; Mehreen Lateef; Lubna Iqbal; Uzma Rasheed Mughal; Rasool Bakhsh Tareen Abstract: This study was designed to explore the phytochemical screening, total phenolic contents, radical scavenging potential and urease inhibitory activities in various fractions of the aerial parts of Nepeta praetervisa. Sub-fractions (n-hexane, chloroform, ethyl acetate, n-butanol, and aqueous) were prepared from the crude methanolic extract using partition chromatography. Phytochemical tests were performed and revealed the presence of various classes of secondary metabolites in various sub-fractions (Table-1). Total phenolic contents of all the fractions were determined using Folin-Ciocalteu (FC) reagent and the ethyl acetate sub-fraction was found to possess the highest level of phenolic contents (627.25 mg gallic acid equivalent (GAE)/g) as compared to the other fractions. The radical scavenging activity was determined at various concentrations ranging from 2.5 - 0.15µg /10µL by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) method. At the lowest concentration level, the ethyl acetate sub-fraction showed maximum level of antioxidant activity (78%) compared to BHA used as standard. The decreasing order of activity was ethyl acetate>chloroform>aqueous>n-butanol>methanol>n-hexane. On the other hand when all these fractions were screened for urease inhibition activity using indophenols method, the ethyl acetate sub-fraction showed significant urease inhibitory activity (68 %) compared with the standard thiourea at the concentration of 50 µg /10 µL. The decreasing order of activity of various sub-fractions was ethyl acetate>chloroform>hexane>aqueous, while n-butanol sub- fraction was inactive. 2013-10-20T00:00:00Z http://localhost:80/xmlui/handle/123456789/19876 Title: Electrochemical Analysis of Phenols through Charging of Phenol Solutions: A New Approach to Electrochemical Analysis of Phenols Authors: Zahid Hussain; Nadia Bashir; Nisar Ahmad; Shahnaz Perveen Abstract: Five different phenols including catechol, hydroquinone, phenol, phloroglucinol and resorcinol were analyzed using a novel electrochemical method of analysis. This method exploits the properties of the phenols to store electricity due to their relative tendency for oxidation or reduction. By using two phenols half cells connected through a salt bridge made-up of card board resulted in the formation of an electrochemical cell. Phenol solution was used as anodic half and reference and sodium hydroxide as electrolyte in these investigations and the electrodes were made-up of the graphite. Optimum conditions and lowest detectable concentration of the phenols were also investigated. The voltage of the battery was found to have linear relationship with the concentration. It was observed that the method is sensitive to 5x10-4 molar concentrations of the phenols. This method is proposed for the determination of the antioxidant activity of the phenols due to the relative difference in the charging capacity and tendency to act as anodic or cathodic half. 2013-10-20T00:00:00Z http://localhost:80/xmlui/handle/123456789/19875 Title: Investigation of a New Spectrophotometric Method for the Analysis of Carbohydrates using glucose as model Authors: Zahid Hussain; Khalid Mohammed Khan; Asif Ali; Nasr ullah Shah; Shahnaz Perveen Abstract: Carbohydrates are biomolecule of significant importance. Its analysis is of prime importance in the clinical investigations, delivery of medicines and quality control operations of food and fuel products. Based on its importance a novel spectrophotometric method was investigated for the trace analysis of carbohydrates using glucose as model carbohydrate. This method is based on glucosazation followed by oxidation of the glucosazone with acidified iron (III) chloride. Oxidation of the glucsazone is necessary for enhancing the color intensity and optimum conditions were investigated for the process. All the absorbance measurements were carried out using 390 nm as λmax. The ratio of the reactants was 1: 1.5: 0.1 mole for the glucose, phenyl hydrazine and iron (III) chloride. This method was used for the analysis of carbohydrates in real samples from plants, industrial products, blood and urine using glucose as reference. 2013-10-20T00:00:00Z http://localhost:80/xmlui/handle/123456789/19874 Title: Preparation of Bioorganic Rechargeable Battery Using Urea and Chickpea Protein for the Storage and Generation of Electrical Power Authors: Zahid Hussain; Khalid Mohammed Khan; Aman Ullah; Akram Shah; Faiq Saeed; Shahnaz Perveen Abstract: The concept of the organic rechargeable battery is introduced. This battery is using urea as oxidation half and the aqueous extract of chickpea as reduction half due to the reversible electrochemical oxidation and reductions of the of the urea and chickpea proteins. Organic rechargeable battery is composed of five cells. Each of the half cell of which is made of a cubical container of high density polyethylene joined to the other through epoxy resin. Non porous graphite rods of 40 mm diameter and 400 mm length were used as the inert electrodes of the battery. The electrodes were placed in aqueous solutions of urea and chick pea extract in separate containers. Sodium hydroxide was used as the electrolyte of the process. The experimental conditions for this five cell battery were optimized. The net voltage and the stability of the voltage were investigated. The variation in stability and voltage was investigated as a function of the salt bridge, concentration of electrolyte, amount of oxidizing and reducing agent and the viscosity of the media. The battery prepared was giving a voltage of 9.5 volt. 2013-10-20T00:00:00Z