Alteration of paracetamol pharmacokinetics in BALB/C mice infected with Schistosoma mansoni

Objective: To determine whether the BALBIC mouse is a suitable model for the study of drug pharmacokinetics in S.rnansoni infection. Design: Male and female BALBIC mice were exposed to cercariae of Smansoni. At the acute (eight weeks post infection) and chronic (14 weeks post infection) stages of infection the animals were treated (i.p.) with a single injection of paracetamol. The pharmacokinetics of paracetamol were then determined for each group and compared to their respective controls. Subjects/Mode1: B ALBIC mice. Setting: Laboratory study. Main Outcome Measures: The altered pharamacokinetics observed in Smansoni infected mice are similar to those observed for humans. Results: Our data indicate that in both sexes of mice at both stages of infection with S.mansoni the Cmar was not dramatically reduced while the Tmax was delayed. The alterations are more pronounced at the chronic stage of infection. These results are similar to those obtained by other workers studying humans. Conclusion: The BALBIC mouse is likely to be a suitable model for the study of pharmacokinetics of selected drugs in schistosome infection.,Research Board, University of Zimbabwe and the International Programme in Chemical Sciences, Uppsala Univerity, Sweden

Effects of DIMBOA on detoxification enzymes of the aphid Rhopalosiphum padi (Homoptera: Aphididae)

The presence of glutathione transferases and esterase activity was investigated in Rhopalosiphum padi and the effects of the cereal hydroxamic acid, 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) on these detoxification enzymes was studied. Activity of glutathione S-transferases and general esterases was determined for adult aphids feeding on a natural diet lacking DIMBOA and on an artificial DIMBOA-containing diet for 48 hours. In vivo, DIMBOA in the diet inhibited the activities of esterases by 50-75% at all concentrations tested (0.5-4 mM). The activity of glutathione transferase was inhibited to a lesser extent (30%) at the higher concentrations of DIMBOA. In vitro, DIMBOA generally inhibited the activity of esterases with an IC50 of 33 μM, and had a slight inhibitory effect on glutathione S-transferases. These effects of DIMBOA could make the aphids vulnerable to electrophilic agents and insecticides which may be metabolized via esterases and GSTs. In cereals, therefore, D

EFFECT OF GERMINATION AND ROASTING ON THE PROXIMATE, MINERAL AND ANTI-NUTRITIONAL FACTORS IN FINGER MILLET (Eleucine coracana), COWPEAS (Vigna unguiculata) AND ORANGE MAIZE (Zea mays)

Finger millet (Eleucine coracana), cowpea (Vigna unguiculata), and bio-fortified vitamin A “orange” maize (Zea mays) are three nutrient dense crops currently being promoted in Zimbabwe. The effect on nutrient content of processing these specific crop varieties has not been investigated. Therefore, this study was designed to determine the effects of germination and roasting on the proximate, mineral, and antinutritional factors in finger millet, cowpeas and orange maize. Finger millet grains were germinated for 48hrs, cowpeas and orange maize for 24hrs, at room temperature (20-23oC). Both raw and processed samples were dried and milled into flour for the determination of proximate and mineral and anti-nutritional composition. Protein content of finger millet increased significantly after processing from 6.53±0.25 mg/100 g to 11.27±0.15 mg/100 g in germinated finger millet flour (P<0.05). Germination of finger millet resulted in significantly increased minerals (mg/100 g); calcium from 345.53±0.55 to 352.63±0.21, zinc from 3.59±0.15 to 8.71±0.01, sodium from 49.89±0.16 to 57.78±1.20 and iron content from 3.75±0.05 to 4.52±0.01 whilst magnesium and potassium decreased significantly from 198.09±0.07 to 69.08±0.06 and 487.08±0.03 to 144.78±0.27 respectively. Processing of cowpeas resulted in slight but significant increase in protein content (20.47±0.21 to 28.50±0.10), increased calcium (138.18±0.12 to 148.18±0.12 mg/100 g), magnesium (14.23±2.00 to 19.18±0.31 mg/100 g), potassium (232±4.00 to 443.41±0.02 mg/100 g) and iron (4.85±0.03 to 4.86±0.04 mg/100 g). Conversely zinc and sodium decreased from 4.5±0.30 to 2.9±0.10 mg/100 g and 31.85±0.03 to 11.64±0.02 mg/100 g, respectively. Notably for orange maize, protein content did not change from 10.06±0.04 to 10.04±0.04 g/100 g before and after processing. Calcium increased from 47.02±2.82 to 57.99±8.85 (mg/100 g), magnesium from 90.91±0.11 to 108.30±0.53 (mg/100 g), potassium from 2.13±0.04 to 4.33±0.25 (mg/100 g), sodium from 0.50±0.02 to 0.70±0.02 (mg/100 g) and iron from 0.50±0.02 to 1.25±0.05 (mg/100 g). Zinc decreased from 6.2±0.2 to 3.53±0.55 (mg/100 g). Tannins, oxalates and phytates decreased significantly after processing of all three crops. Results showed that germination and roasting increased the nutritional profile and decreased anti-nutrient content in finger millet, cowpeas and orange maize. Therefore, it is important to consider germinating and roasting these grains during processing to increase the nutritional potential of the end food product. Further studies are required to investigate the decrease in some nutrients after germination and roasting and possibly establish optimum processing parameters for improved nutrient profile of these food crops

EFFECT OF GERMINATION AND ROASTING ON THE PROXIMATE, MINERAL AND ANTI-NUTRITIONAL FACTORS IN FINGER MILLET (Eleucine coracana), COWPEAS (Vigna unguiculata) AND ORANGE MAIZE (Zea mays)

Finger millet (Eleucine coracana), cowpea (Vigna unguiculata), and bio-fortified vitamin A “orange” maize (Zea mays) are three nutrient dense crops currently being promoted in Zimbabwe. The effect on nutrient content of processing these specific crop varieties has not been investigated. Therefore, this study was designed to determine the effects of germination and roasting on the proximate, mineral, and antinutritional factors in finger millet, cowpeas and orange maize. Finger millet grains were germinated for 48hrs, cowpeas and orange maize for 24hrs, at room temperature (20-23oC). Both raw and processed samples were dried and milled into flour for the determination of proximate and mineral and anti-nutritional composition. Protein content of finger millet increased significantly after processing from 6.53±0.25 mg/100 g to 11.27±0.15 mg/100 g in germinated finger millet flour (P<0.05). Germination of finger millet resulted in significantly increased minerals (mg/100 g); calcium from 345.53±0.55 to 352.63±0.21, zinc from 3.59±0.15 to 8.71±0.01, sodium from 49.89±0.16 to 57.78±1.20 and iron content from 3.75±0.05 to 4.52±0.01 whilst magnesium and potassium decreased significantly from 198.09±0.07 to 69.08±0.06 and 487.08±0.03 to 144.78±0.27 respectively. Processing of cowpeas resulted in slight but significant increase in protein content (20.47±0.21 to 28.50±0.10), increased calcium (138.18±0.12 to 148.18±0.12 mg/100 g), magnesium (14.23±2.00 to 19.18±0.31 mg/100 g), potassium (232±4.00 to 443.41±0.02 mg/100 g) and iron (4.85±0.03 to 4.86±0.04 mg/100 g). Conversely zinc and sodium decreased from 4.5±0.30 to 2.9±0.10 mg/100 g and 31.85±0.03 to 11.64±0.02 mg/100 g, respectively. Notably for orange maize, protein content did not change from 10.06±0.04 to 10.04±0.04 g/100 g before and after processing. Calcium increased from 47.02±2.82 to 57.99±8.85 (mg/100 g), magnesium from 90.91±0.11 to 108.30±0.53 (mg/100 g), potassium from 2.13±0.04 to 4.33±0.25 (mg/100 g), sodium from 0.50±0.02 to 0.70±0.02 (mg/100 g) and iron from 0.50±0.02 to 1.25±0.05 (mg/100 g). Zinc decreased from 6.2±0.2 to 3.53±0.55 (mg/100 g). Tannins, oxalates and phytates decreased significantly after processing of all three crops. Results showed that germination and roasting increased the nutritional profile and decreased anti-nutrient content in finger millet, cowpeas and orange maize. Therefore, it is important to consider germinating and roasting these grains during processing to increase the nutritional potential of the end food product. Further studies are required to investigate the decrease in some nutrients after germination and roasting and possibly establish optimum processing parameters for improved nutrient profile of these food crops

Modulation of Anopheles gambiae Epsilon glutathione transferase activity by plant natural products in vitro

Elevated glutathione transferase (GST) E2 activity is associated with DDT resistance in the mosquito Anopheles gambiae. The search for chemomodulators that inhibit the function of AgGSTE2 would enhance the insecticidal activity of DDT. Therefore, we examined the interaction of novel natural plant products with heterologously expressed An. gambiae GSTE2 in vitro. Five of the ten compounds, epiphyllocoumarin(Tral-1), knipholone anthrone, isofuranonaphthoquinones (Mr 13/2, Mr 13/4) and the polyprenylated benzophenone (GG1) were shown to be potent inhibitors of AgGSTE2 with IC50 values of 1.5 mu M, 3.5 mu M, 4 mu M, 4.3 mu M and 4.8 mu M respectively. Non-competitive inhibition was obtained for Tral 1 and GG1 with regards to GSH (K-i of 0.24 mu M and 0.14 mu M respectively). Competitive inhibition for Tral1 was obtained with CDNB (K-i = 0.4 mu M) whilst GG1 produced mixed type of inhibition. The K-i and K-i' for GSH for Tral-1 and GG1 were 0.2 mu M and 0.1 mu M respectively. These results suggest that the novel natural plant products, particularly Tral-1, represent potent AgGSTE2 in vitro inhibitors