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Fats and oils are both economically and scientifically important in food systems and play an important role in nutrition. The principal causes of fat degradation are oxidation and hydrogenation, which have a detrimental impact on quality aspects of oils and fats such as color, texture, flavor, aroma, consistency, and appearance. The current research was conducted to determine the oil degradation factors by collecting fifty samples of fried oils used by street vendors from twenty -five different locations in Faisalabad area in order to assess the quality parameters of locally available fats and oil products. Procured samples underwent physicochemical tests to determine the degree of degradation and oxidation. The parameters analyzed for quality evaluation include free fatty acids (FFA), peroxide value (PV), iodine value (IV), saponification value (SV), viscosity, refractive index (RI), p-anisidine value (p-AV), thiobarbeturic acid value (TBA), specific gravity (SG) and fatty acid profile through gas chromatograph equipped with flame ionization detector. The analyses revealed significant oxidation and degradation in many of the vendor fried fats and oil that were procured. Physicochemical characteristics as well as oxidative stability attributes were deviated from the standard values defined by Codex Alimentarius and Punjab Pure Food Regulations (PPFR). In majority of the samples, the fatty acid profile exhibited increased levels of trans-9-elaidic acid and linolelaidic acid, indicating the presence of trans-fatty acid because of hydrogenation and high-temperature frying of fats and oils. The overall quality of most procured samples was in decline from recommended standards and unsuitable for frying and edible purposes. [ABSTRACT FROM AUTHOR]

In this experiment, effect of lead (Pb) + chromium (Cr) mixture on superoxide dismutase (SOD) in the liver of Labeo rohita at a concentration of 11.1 mgL-1 was observed. The ammonium sulphate precipitation and ion exchange chromatography techniques were successfully used to purify SOD. After purification, SOD activity of control and Pb+Cr treated fish was noted as 581.00 and 645.45 UmL-1, respectively while the specific activity was 1383.33 and 1613.62 Umg-1, respectively. The fold purification value of SOD was 2.75 and 2.45 for control and stressed fish, respectively. The recovery was calculated as 77.06 and 57.43% for control and stressed fish, respectively. The results of kinetic characterization showed that SOD form control and exposed fish had maximum activity at pH 6.5 and 7.0. Temperature also had a significant effect on activity of SOD. The SOD activity was measured maximum at 30°C for both control and Pb+Cr exposed fish. The Km value of liver SOD for control and Pb+Cr treated L. rohita was calculated as 1.48 and 0.62 mM, respectively. The value of Vmax for SOD from liver of control and Pb+Cr exposed fish was 1000 and 570 U mL-1, respectively. The enthalpy of denaturation (ΔH*) for liver SOD from control and Pb+Cr exposed L. rohita was computed as 3.492 and 2.802 KJ mol-1 at 40°C, respectively and these values were dropped off with increasing the temperature until it remains 3.251 and 2.561 KJ mol-1 at 70°C, respectively. The free energy of thermal denaturation (ΔG°) of liver SOD was slightly increased with increasing temperature until 75°C which shows its resistance against heat. The values of ΔG° was observed as 58.03 and 57.95 KJ mol-1 for control and exposed fish at 40°C, respectively while the same was increased upto 62.37 and 62.00 KJ mol-1 at 70°C, respectively. It was concluded from negative value of ΔS* (entropy of inactivation) that the SOD is stable thermodynamically. [ABSTRACT FROM AUTHOR]

Medicinal plants used for the treatment of chronic diseases, have attracted the interest of scientists. L-Asparaginase is an extracellular enzyme with biomedical significance. The present article discusses the extraction, purification and characterization of L-asparaginase. Enzyme activity was estimated from Chillies (plant of Solanaceae family). Enzyme titer of 112 U/mL was attained from crude extract of Chillies (Capsicum annum) fruit while purified enzyme after gel filtration provided 61.99% yield, activity of 69.43 U/mL and specific activity of 234 U/mg. L-Asparaginase stability was envisaged at optimal pH of 8.6 in the presence of alkaline buffer. Optimal substrate concentration for L-Asparaginase activity was 200 mMoL. The efficacy of purified enzyme was tracked in vivo model. Normal healthy rats were used as control, which were compared with leukemic rats after treatment with enzyme L-Asparaginase. Eventually after treatment with enzyme extract provided best recovery in leukemic model due to high titer of L-Asparaginase, which bears high antineoplastic activity. It may be employed for chemotherapy in tumors such as acute lymphocytic leukemia. [ABSTRACT FROM AUTHOR]

A study was conducted to purify and characterize a novel protease produced from Aspergillus niger using different lignocellulosic agro-based by-products including corncobs, wheat bran, and rice bran as substrates under SSF. Maximum protease activity was recorded on wheat bran fermented culture media after the 3rd day of incubation. The optimal conditions found for protease production using wheat bran were cultivation period (3 days), substrate concentration (10 g), pH (7), incubation temperature (45°C), inoculum size (4 mL), and 3% surfactant Tween-80 (2 mL). A purification fold of 2.41 with 29 U/mg specific activity and 70.73 % recovery was achieved after purification. Purified protease from A. niger had a molecular weight of 47 kDa on SDS-PAGE. The enzyme activity profile showed that purified protease was optimally active at pH 7 and 45°C as optimum values. A. niger protease was reasonably stable in the pH range 5-8 and 35-60°C for up to 1 h incubation. Protease was activated by various metal ions/inhibitors tested, Mn2+, Cd2+, Mg2+, Cu2+, PMSF, Pepstatin and Iodoacetic acid at 1 mM, proving the enzyme as metalloprotease, whereas an inhibitory effect was shown by certain agents including EDTA and SDS. The purified protease was compatible with five local detergents with up to 25 days of shelf life at room temperature. The maximum production of protease in the presence of a cheaper substrate at low concentration and its potential as a detergent additive for improved washing makes the strain and its enzymes potentially useful for industrial purposes, especially for the detergent and laundry industry. [ABSTRACT FROM AUTHOR]