6 research outputs found
Determination of 4,4-(propane-2,2-diyl) diphenol (Bisphenol A) Concentration in Canned Tomatoes
Bisphenol A (BPA) is a chemical used in the production of polycarbonate plastics and for lining metal cans, used in canned foods. BPA is a well-known endocrine disrupting chemical, it therefore, is very hazardous to human health. BPA levels were determined in three brands of canned tomatoes (Gino, Super Mama, Derica) as sold in Nigerian markets. The samples were analyzed using solvent extraction, separation and quantitation by gas chromatography- mass spectrometric method. The recovery value for BPA in the method was 89% with the relative standard deviations of 3%.The BPA concentration in the samples ranged from 0.124 to 0.141 (), which are higher than the European Food Safety Authority Specific Migration Limit (SML) of 0.05 mg/kg in food sample. The samples analyzed in this work may be, therefore, of a potential health concern to the consumers
Polymerization of gallic acid enhances its antioxidant capacity: Implications for plant defence mechanisms
Gallic acid (3, 4, 5-trihydroxybenzoic acid, GA) and its polymer,
tannic acid (TA) are ubiquitous phytochemicals and are found to
co-exist in plants. However, the rationale for the polymerisation of GA
in plants is rather obscure. Hence, the present study compared the free
radical scavenging ability, iron chelating potency, ferric reducing
antioxidant power and inhibitory potential of both GA and TA against
deoxyribose and lipid oxidative assaults in vitro. The results show
that TA exhibited marked free radical scavenging ability as well as
chelate Fe2+ and reduce Fe3+ more effectively than GA. Furthermore,
this differential antioxidant capacity is also observed in the ability
of both polyphenols to protect against hydroxyl radical induced
deoxyribose degradation in the Fenton reaction. Similarly, in
comparison with GA, TA also exerted marked inhibitory effect against
mammalian cerebral and hepatic lipids assaulted with different
prooxidants possessing diverse mechanisms of action. The present
finding suggests that the polymerisation of GA to form a more efficient
radical scavenger may have be associated with the need for increased
antioxidant capacity required to cope with disturbed redox balance
associated with pathological conditions in plants in which free radical
induced oxidative stress may be implicated in their etiologies
Polymerization of gallic acid enhances its antioxidant capacity: Implications for plant defence mechanisms
Gallic acid (3, 4, 5-trihydroxybenzoic acid, GA) and its polymer,
tannic acid (TA) are ubiquitous phytochemicals and are found to
co-exist in plants. However, the rationale for the polymerisation of GA
in plants is rather obscure. Hence, the present study compared the free
radical scavenging ability, iron chelating potency, ferric reducing
antioxidant power and inhibitory potential of both GA and TA against
deoxyribose and lipid oxidative assaults in vitro. The results show
that TA exhibited marked free radical scavenging ability as well as
chelate Fe2+ and reduce Fe3+ more effectively than GA. Furthermore,
this differential antioxidant capacity is also observed in the ability
of both polyphenols to protect against hydroxyl radical induced
deoxyribose degradation in the Fenton reaction. Similarly, in
comparison with GA, TA also exerted marked inhibitory effect against
mammalian cerebral and hepatic lipids assaulted with different
prooxidants possessing diverse mechanisms of action. The present
finding suggests that the polymerisation of GA to form a more efficient
radical scavenger may have be associated with the need for increased
antioxidant capacity required to cope with disturbed redox balance
associated with pathological conditions in plants in which free radical
induced oxidative stress may be implicated in their etiologies
Determination of polycyclic aromatic hydrocarbons (PAHs) in commonly consumed Nigerian smoked/grilled fish and meat
Smoking and/or grilling, when carried out with traditional methods involving direct contact with wood combustion fumes, is responsible for high contamination levels with carcinogenic polycyclic aromatic hydrocarbons (PAHs). The aim of this work was to investigate the PAH content of different smoked or grilled meat and fish products commonly consumed in Nigeria. A rapid method involving microwave-assisted saponification and simultaneous extraction followed by solid-phase extraction (SPE), high-performance liquid chromatography (HPLC) separation and spectrofluorometric detection was employed. Samples that were smoked or grilled using traditional systems, which use a wood fire, were heavily contaminated with benzo[a]pyrene (BaP) at levels ranging from 2.4 to 31.2 \u3bcg kg-1 wet weight. Considerably lower contamination levels were found in samples smoked or grilled in the laboratory using a charcoal fire (BaP from 0.7 to 2.8 \u3bcg kg-1 wet weight). The health risk associated with a daily consumption of 100 g of these products was also evaluated using the margin of exposure (MOE) approach. MOE values lower than 10,000 were obtained for all smoked/ grilled commercial samples, indicating a potential concern for consumer health