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In this study, simple, new and functional silky nanostructures of Co3O4 are prepared by hydrothermal method. These nanostructures are successfully used for the enzyme free sensing of uric acid in 0.1 M phosphate buffer solution of pH 7.3. Physical characterization experiments were carried out to explore the morphology, composition and crystalline phase of the newly prepared Co3O4 nanostructures. Scanning electron microscopy (SEM) shows a silk like morphology and energy dispersive spectroscopy (EDS) revealed the presence of Co and O as the main elements. Powder X-ray diffraction (XRD) demonstrates a cubic crystallography with well resolved diffraction patterns. The electrochemical activity of these silky Co3O4 nanostructures was evaluated by cyclic voltammetry (CV) in a 0.1 M phosphate buffer solution at pH 7.3. The high purity and unique morphology of Co3O4 shows a highly sensitive and selective response towards the non-enzymatic sensing of uric acid. This uric acid sensor exhibits a linear range of 0.5 mM to 3.5 mM uric acid and a 0.1 mM limit of detection. The anti-interference capability of this uric acid sensor was monitored in the presence of common interfering species. Furthermore, electrochemical impedance spectroscopy confirms a low charge transfer resistance value of 5.11 K Ω cm2 for silky Co3O4 nanostructures which significantly supported the CV results. The proposed modified electrode is stable, selective and reproducible which confirms its possible practical use. Silky Co3O4 nanostructures can be of great importance for diverse electrochemical applications due to their excellent electrochemical activity and large surface area.

In this study, a simple approach was used to produce nonprecious, earth abundant, stable and environmentally friendly NiCo2O4/CuO composites for the oxygen evolution reaction (OER) in alkaline media. The nanocomposites were prepared by a low temperature aqueous chemical growth method. The morphology of the nanostructures was changed from nanowires to porous structures with the addition of CuO. The NiCo2O4/CuO composite was loaded onto a glassy carbon electrode by the drop casting method. The addition of CuO into NiCo2O4 led to reduction in the onset potential of the OER. Among the composites, 0.5 grams of CuO anchored with NiCo2O4 (sample 2) demonstrated a low onset potential of 1.46 V vs. a reversible hydrogen electrode (RHE). A current density of 10 mA cm−2 was achieved at an over-potential of 230 mV and sample 2 was found to be durable for 35 hours in alkaline media. Electrochemical impedance spectroscopy (EIS) indicated a small charge transfer resistance of 77.46 ohms for sample 2, which further strengthened the OER polarization curves and indicates the favorable OER kinetics. All of the obtained results could encourage the application of sample 2 in water splitting batteries and other energy related applications.

Summary In this study, a total of 84 milk samples (60 nonbranded and 24 branded) were analysed for occurrence of oxytocin (OT) residues by ELISA. OT level was detected in the range of 39.29–456.55 pg mL−1 with mean value of 138.53 ng L−1. In branded milk samples, OT residues were minimal as compared to nonbranded milk samples. Nonbranded milk samples had higher prevalence of OT residues; 16.67% had OT level in the range of ≤500 ng L−1. The average daily intake of OT was found 0.087 μg day−1 per person. It was concluded that the OT concentration was relatively higher in samples obtained from dairy farm, dairy shop and milk man than that in ultra-high temperature (UHT) and powder milk samples. In addition, there are no reports subjected to standardising a permissible OT level in dairy milk category, although OT is considered detrimental to both human and animal life.

An efficient and simple in situ ultrasonic assisted esterification method has been developed for gas chromatographic determination of benzoic acid (BA) in raw and processed milk samples. For optimization of variables, chemometric approach was employed using Plackett–Burman design (PBD) and face-centered central composite design (FCCCD). Firstly, major factors affecting benzoic acid methyl ester (BAME) yield, i.e., BA concentration, volume of methanol, sonication time, amount of milk, and sulfuric acid, were studied with PBD. After screening significant factors, further optimization was carried out with FCCCD. Analysis of variance (ANOVA) of the quadratic model demonstrated that BA concentration, interaction factors of BA with sulfuric acid, and methanol volume significantly (p < 0.05) affect the BAME %yield. The proposed in situ method has better BAME limit of detection (0.02 mg/L) and quantification (0.07 mg/L) for the rapid determination of BA in milk samples avoiding the use of sample pretreatment and solvent extraction step.

In the present studies efforts are made to develop a low cost method to remove pesticides from water streams. Low cost walnut shells after chemical and thermal treatment are used to remove carbofuran and Chloropyriphos pesticides from aqueous solutions. The adsorption parameters i.e. pH, contact time, shaking speed and initial concentration have been studied. The adsorption was found to be rapid 97-99% within 30 min. The adsorption of pesticides on the adsorbent surface was found to be pH dependent. The adsorbent material was characterized by scanning electron microscopy (SEM) analysis and FT-IR spectroscopy. Elution experiments were performed to recover the adsorbed pesticide from the adsorbent surface. The Freundlich, Langmuir, D-R and Thomas models were used to study the partitioning behavior for the adsorption system along with kinetic and thermodynamic studies. The proposed adsorption method was utilized to remove carbofuran and Chloropyriphos pesticides from environmental water samples. Key word: Adsorption; pesticides; Walnut shell; Isotherms, Kinetics; thermodynamics.

The effect of different cooking methods (Raw, steaming, microwave cooking, baking, grilling, pan frying and deep frying) on proximate composition and fatty acid profile of Labeo calbasu fish species from Pakistan were analyzed to determine the nutritional qualities in terms of the long chain n-3 PUFA particularly EPA and DHA. In all cooking methods moisture content decrease and protein content increased as compare to raw sample. The moisture content of fish sample seemed to be inversely related to the total extractable lipid content. In steamed, microwave, baked, grilled and pan fried methods MUFA were the abundant fatty acids followed by SFA and PUFA. Deep fried fish sample had the opposite trend having highest PUFA as contrast to MUFA and SFA. Long chain n-3 PUFA were found higher in contrast to n-6 PUFA in all other cooking methods excluding deep frying. The results indicates that steamed and grilled cooking are the best cooking method for healthy eating as they contain more n-3 PUFA (EPA and DHA). Losses of n-3 content in pan fried and deep fried fish were higher than those of fish cooked by other methods.

This study was carried out to determine the proximate composition, fatty acid profile and biometric data for farm fish species Labeo rohita , Cirrhinus mrigala , Catla catla raised under identical conditions. The analysed fish species were found as source of high polyunsaturated fatty acids with low fat high protein. Fat content of the fish fillets was in range 2.57–3.11 g/100 g. Whereas fat content for feed was 14.90 g/100 g. The protein level for the three fish ranged from 20.00–23.57 g/100 g and in feed it was estimated in the range of 67.70 g/100 g. The palmitic acid and stearic acid were the main saturated fatty acids (SFA), oleic acid was the predominant MUFA while the docosahexanoic acid and eicopentanoic acid were the major PUFA. The percentage of DHA exceeded that of EPA in all fish species analysed. The n−3/n−6 ratio ranged from 1.69–1.91. PUFA/SFA ratio was much higher in L. rohita (1.40) due to abundance of n−3 PUFA, particularly DHA.

Eight species of freshwater fish from the Indus River were analyzed for their proximate composition and fatty acid (FA) profile. Differences were observed (P < 0.05) for moisture (59.95–79.45%), ash (0.05–4.95%), crude protein (17–20.09%) and lipid (0.85–18.32%) contents. The changes in FA profiles of fish species were significant (P < 0.05). The monounsaturated (MUFA) fatty acid content (24.55–48.35 g/100 g) was higher than the saturated fatty acid (SFA) (25.04–41.02 g/100 g) and polyunsaturated fatty acid (PUFA) (15.72–35.34 g/100g). The predominant PUFAs were eicosapentaenoic acid (C20:5 n-3) and docosahexaenoic acid (C22:6 n-3). All of the fish species had n-3/n-6 within the recommended values (1–4), which confirms he importance of River Indus fish as a significant dietary source of n-3 PUFA.

The present study was undertaken to evaluate the breed influence on milk fatty acid (FA) composition, particularly on the concentration of conjugated linoleic acid (CLA) from two different indigenous breeds of goats (Pateri and Kamori; n = 30 for each breed) and ewes (Kachi and Kooka; n = 25 for each) from Sindh, Pakistan. All animals were managed together and received the same diet. Statistical significant differences ( P cis -9, trans -11 CLA concentration from Kamori goats and Kooka ewes were [17–28%] higher when compared to Pateri goats and Kachi ewes, with mean values of 0.48 g/100 g for goat breeds and 0.82 g/100 g for ewes. The greatest differences ( P P > 0.05) among goat and ewe breads, ranging from 2.45 to 3.60 for goats and 2.48 to 3.27 g/100 g for ewes. The present study reveals that the breed has a pronounced effect on FA composition of goat and ewes milk fat, and in the future genetic selection plans along with improved nutrition program of goats and ewes may result in optimum levels of various fatty acids in milk.

Six fish speciesCirrhinus mrigala (Morakhi), Labeo rohita (Danbhro), Catla catla (Thalli), Wallago attu (Jarko), Ctenopharyngodon idella (Grass), and Cyprimus carpio (Gulfam)commonly found in the Pakistani Indus river, were selected for fat and cholesterol evaluation. Fat content was quantified by the Folch method and cholesterol content was determined by a simple GC method. The application of the proposed method to quantify cholesterol content revealed variations among the six breeds evaluated. The breeds studied contained 0.801.95 fat, indicating that all investigated fishes were lean; significant variation was found in cholesterol content, and ranged between 72 and 392 mg/100 g. Standard addition analyses showed that the method was accurate, as the recovery of cholesterol varied from 95 to 103, with a coefficient of variance not more than 5.6. The results showed that, after the development of suitable calibration, within 11 min, the cholesterol could be accurately determined by GC.