Assessing the status of food safety management systems for fresh produce production in East Africa: evidence from certified green bean farms in Kenya and noncertified hot pepper farms in Uganda.

The farms of fresh produce farmers are major sources of food contamination by microbiological organisms and chemical pesticides. In view of their choice for farming practices, producers are influenced by food safety requirements. This study analyzes the role of food safety standard certification toward the maturity of food safety management systems (FSMS) in the primary production of fresh produce. Kenya and Uganda are two East African countries that export green beans and hot peppers, respectively, to the European Union but have contrasting features in terms of agricultural practices and certification status. In the fresh produce chain, a diagnostic instrument for primary production was used to assess context factors, core control and assurance activities, and system output to measure the performance of FSMS for certified green bean farms in Kenya and noncertified hot pepper farms in Uganda. Overall, our findings show that in Uganda, noncertified hot pepper farms revealed only a "basic level of control and assurance" activities in their FSMS, which was not satisfactory, because no insight into potential pesticide microbial contamination was presented by these farmers. On the other hand, certified green bean farms in Kenya had an "average level of control and assurance," providing insight into the delivered food safety and quality by the farmers. Farm size did not impact the maturity level of FSMS. This study confirms the role played by food safety standard certification toward the maturity of FSMS implemented in developing countries and demonstrates the possibility of Ugandan farms to upgrade agricultural practices in the fresh produce sector.

Pharmacological studies of two antidiabetic plants: Globularia alypum and Zygophyllum gaetulum.

Investigations were carried out to evaluate the hypoglycaemic activity of the infusions of Globularia alypum and Zygophyllum gaetulum. Oral and intraperitoneal administration of the plants (0.7 g/kg) produced a significant hypoglycaemic effect in normal as well as in hyperglycaemic rats. The infusions increased significantly plasma insulin levels in normal rats. It is suggested that the hypoglycaemic activity of these plants may be mediated through enhancement of peripheral metabolism of glucose and an increase in insulin release.

Inhibition of glucose metabolism by progesterone in adipocytes: role of protein synthesis.

Progesterone decreases [I-14C]glucose oxidation in isolated female rat adipocytes within 20 min of incubation. Because steroids regulate transcription mechanisms, the relationship between protein synthesis and glucose metabolism was studied in the presence of progesterone. Actinomycin D does not affect basal glucose oxidation or the progesterone effects on it; cycloheximide and puromycin decrease basal glucose oxidation, but only puromycin decreases the inhibitory progesterone effect. Although puromycin inhibits glucose transport, the common site of action of puromycin and progesterone does not seem to be glucose transport, which, as we showed previously, is not modified by the steroid. Incorporation of [3H]leucine into acid-precipitable proteins is decreased by puromycin and cycloheximide but not by actinomycin D or progesterone; moreover, the action of these inhibitors does not change in the presence of the steroid. As shown by electrophoresis (SDS-PAGE) and autoradiography, L-leucine is incorporated into adipocyte proteins as early as 20 min and progesterone increases this incorporation into five proteins. Leucine is a ketogenic amino acid that is also incorporated into lipids; progesterone depresses L-leucine incorporation into fatty acids by a glucose-dependent mechanism. These results suggest that the inhibitory effect of progesterone on glucose metabolism is related to an enhanced protein synthesis counterbalanced by decreased fatty acid synthesis.

Progesterone and synthetic steroids produce insulin resistance at the post-receptor level in adipocytes of female rats.

The effects of progesterone, its agonists (progestin RU-5020, glucocorticoid RU-26988) and antagonist (antiprogesterone, anti-glucocorticoid RU-486) were tested on isolated fat cells in vitro. When added to the incubation medium, all four steroids decreased basal glucose oxidation. The inhibitory effect of the steroids appeared early (20 min incubation) and was sustained during a 2-h incubation. The early inhibitory effect was less marked for progesterone agonist RU-5020 than for the other three steroids. When incubation was prolonged for 2 h, the lowest inhibitory effect was observed with progesterone antagonist RU-486. Insulin-stimulated glucose oxidation was inhibited by progesterone, its antagonist RU-486, one of its agonists RU-26988, but not by the other agonist RU-5020. Analysis of the dose response curves showed that progesterone, RU-26988, and RU-486 decreased fat cells' responsiveness and, only for RU-486, sensitivity to insulin. Adipocytes isolated from ovariectomized, progesterone-treated rats showed a decreased maximal response to insulin and decreased insulin sensitivity in opposition to cells incubated directly with the steroid. No inhibition of 125I-labeled insulin binding was seen as an acute or chronic effect of progesterone. It is concluded that progesterone and the studied related steroids decrease glucose oxidation by mechanism(s) distal to insulin binding to its specific receptors.