Mateen Abbas

Compositional Variation in Sugars and Organic Acids at Different Maturity Stages in Selected Small Fruits from Pakistan

Selected soluble sugars and organic acids were analyzed in strawberry, sweet cherry, and mulberry fruits at different ripening stages by HPLC. The amounts of fructose, glucose and sucrose were found to be: strawberry (1.79–2.86, 1.79–2.25 and 0.01–0.25 g/100 g FW), sweet cherry (0.76–2.35, 0.22–3.39 and 0.03–0.13 g/100 g) and mulberry (3.07–9.41, 1.53–4.95 and 0.01–0.25 g/100 g) at un-ripened to fully-ripened stages, respectively. The strawberry, sweet cherry and mulberry mainly contained tartaric, citric and ascorbic acids in the range of 16–55, 70–1934 and 11–132 mg/100 g; 2–8, 2–10 and 10–17 mg/100 g; 2–118, 139–987 and 2–305 mg/100 g at un-ripened to fully-ripened stages, respectively. Fructose and glucose were established to be the major sugars in all the tested fruit while citric and ascorbic acid were the predominant organic acids in strawberry and mulberry while tartaric acid was mainly present in sweet cherry. The tested fruits mostly showed an increase in the concentration of sugars and organic acids with ripening.

Effect of Maturity on Phenolics (Phenolic Acids and Flavonoids) Profile of Strawberry Cultivars and Mulberry Species from Pakistan

In this study, we investigated how the extent of ripeness affects the yield of extract, total phenolics, total flavonoids, individual flavonols and phenolic acids in strawberry and mulberry cultivars from Pakistan. In strawberry, the yield of extract (%), total phenolics (TPC) and total flavonoids (TFC) ranged from 8.5–53.3%, 491–1884 mg gallic acid equivalents (GAE)/100 g DW and 83–327 mg catechin equivalents (CE)/100 g DW, respectively. For the different species of mulberry the yield of extract (%), total phenolics and total flavonoids of 6.9–54.0%, 201–2287 mg GAE/100 g DW and 110–1021 mg CE/100 g DW, respectively, varied significantly as fruit maturity progressed. The amounts of individual flavonols and phenolic acid in selected berry fruits were analyzed by RP-HPLC. Among the flavonols, the content of myricetin was found to be high in Morus alba (88 mg/100 g DW), the amount of quercetin as high in Morus laevigata (145 mg/100 g DW) while kaempferol was highest in the Korona strawberry (98 mg/100 g DW) at fully ripened stage. Of the six phenolic acids detected, p-hydroxybenzoic and p-coumaric acid were the major compounds in the strawberry. M. laevigata and M. nigra contained p-coumaric acid and vanillic acid while M. macroura and M. alba contained p-hydroxy-benzoic acid and chlorogenic acid as the major phenolic acids. Overall, a trend to an increase in the percentage of extraction yield, TPC, TFC, flavonols and phenolic acids was observed as maturity progressed from un-ripened to fully-ripened stages.

Quantitative Scrutinization of Aflatoxins in Different Spices from Pakistan.

The current research work aimed to access the contamination level of aflatoxins B1, B2, G1, and G2 in the household spices that are widely consumed in huge amounts. 200 different spice samples, 100 packed and 100 unpacked, were analyzed for the aflatoxins profile by HPLC with an incidence of 61.5% contamination out of which 53.66% samples exceed the EU limit. The results disclosed that the unpacked samples are more contaminated as compared to the packed samples except for white cumin seeds. Among packed and unpacked samples of spices, the maximum value of aflatoxins was detected in fennel, that is, 27.93 μg/kg and 67.04 μg/kg, respectively. The lowest concentration of aflatoxin was detected in cinnamon in packed form (0.79 μg/kg) and in the unpacked samples of white cumin seeds which is 1.75 μg/kg. Caraway seeds and coriander in its unpacked form showed positive results whereas black pepper (packed and unpacked) was found free from aflatoxins. This is the first report on the occurrence of aflatoxins in packed and unpacked samples of spices from Pakistan. To ensure safe consumption of spices, there should be constant monitoring of aflatoxin and more studies need to be executed with the intention of preventing mycotoxin accretion in this commodity.

Polymeric microspheres of okra mucilage and alginate for the controlled release of oxcarbazepine: In vitro & in vivo evaluation

Oxcarbazepine-loaded alginate/okra pods mucilage microspheres were prepared through inotropic gelation technique for the sustained release of oxcarbazepine. The drug encapsulating efficiency of these microspheres was found 76.22 ± 0.01% to 90.57 ± 0.02% and their average particle sizes were 496 μm ± 0.41 to 692 μm ± 0.22. These microspheres were characterized in terms of swelling capacity, FTIR, DSC and SEM analysis. The in vitro drug release from these microspheres was followed sustained release (Korsemeyer - Peppas model) pattern (R2 = 0.9552-0.9906) and value of n > 1 showed that drug released by anomalous (non-Fickian) diffusion. The in vivo studies showed that there were highly significant difference with p < 0.001 in the pharmacokinetic parameters (Cmax, t½, AUC0-∞, Ke), when oxcarbazepine was formulated in form of polymeric microspheres as compared to pure drug.

Analysis of Water Soluble Vitamins (Thiamine, Nicotinamide and Pyridoxine) in Fortified Infant Food Products by Hplc

The present study provides information about the levels of fortification of three water soluble vitamins i.e. thiamine (B1), nicotinamide (B3) and pyridoxine (B6) in a variety of foodstuffs include milk products and cereals for young children. Food fortification is key implement for improving health of the growing children. Twenty food samples were chosen for analysis because of their common utilization in the local area. The vitamin concentrations were determined by high performance liquid chromatography with C18 column with a gradient of mobile phase made of water and acetonitrile and a diode array detector set at 280 nm. The thiamine content investigated in the samples ranging from 268 μg/mL to 3 μg/ml, nicotinamide content was from 41 μg/ml to 1 μg/mL while the pyridoxine level was in between 412 μg/mL to 20 μg/mL. Detection and Quantification of compounds were attained by comparing their retention times with standard reference materials and on the basis the off peak area match against those of a standard. The method used, offer excellent linearity with r2 > 0.994, detection limits, reproducibility, and analyte recovery.