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Dioscorea spp., White Yam has been shown to exhibit a wide range of nutritional and medicinal properties. However, the compounds associated with its medicinal functions have not been fully examined. The purpose of this study was to generate a chemoinformatic profile of the bioactive compounds present in Dioscorea. alata (D. alata) and to characterize their putative anti-cancer properties using prostate (DU145) and lung (A549) cancer cells. Chemoinformatic profiling of D. alata resulted in five bioactive extracts: hexane (DaJa-1), ether (DaJa-2), acetone (DaJa-3), ethanol (DaJa-4) and water (DaJa-5) were generated. The analytes present in the five bioactive extracts were dissolved in 0.1% DMSO and their anti-cancer activity were determined. We observed that the acetone extract (DaJa3) was the only extract capable of inducing greater than 90% cell death of DU 145 cell at 100 μg/mL. The order of growth inhibition of the extracts in DU-145 cell is DaJa-3 (IC50, 31.45 μg/mL) > DaJa-4 (IC50 60 μg/mL) > DaJa-1 (IC50 > 100 μg/mL) ≥ DaJa-2 (IC50 > 100 μg/mL) ≥ DaJa-5 (IC50 > 100 μg/mL). MTT cell viability, dye exclusion, caspase activity and microscopic assessment of apoptotic cells demonstrated that DaJa-3 displayed cytotoxicity to both lung and prostate cancer cells. The A549 cells were more sensitive toward DaJa-3 with an IC50 value of 22.28 μg/mL (CI 28.42 to 36.63 μg/mL), compared to that of DU145 cells with an IC50 value of 31.45 μg/mL (CI 27.58 to 35.86 μg/mL). It was also observed that DaJa-3 induces differential anti-proliferative activity in the cancer cells. The apoptotic response induced by DaJa-3 paralleled the level of cell cytotoxicity observed in both cell lines. DaJa-3 induces G2 phase cell cycle arrest in DU145 cells but G1 arrest in A549 cells. The level of key apoptotic regulator proteins was upregulated, suggested that DaJa-3 may be mediating its anti-cancer effect through activation of the intrinsic apoptotic pathway. Altogether, our data indicates that DaJa-3 derived from a staple food source (white Yam) contains unique active compounds that have specific biological properties that may prevent certain types of cancer or specific types of cancer.

Background: Fruits, vegetables and legumes for their complex carbohydrates, dietary fiber and micronutrients, should form an essential part of every diet. In order to give good dietary advice to diabetic patients, it is necessary to know the glycemic index of foods commonly consumed locally. The objective of this study was to determine the Glycemic Index (GI) and Glycemic Load (GL) of commonly available and consumed Guava (Psidium guajava), Watermelon (Citrullus vulgaris), Gungo (Cajanus cajan), Papaya (Carica papaya) and tomato (Solanum lycopersicum) in Jamaica. Methods: Ten (10) healthy Jamaican subjects (5 males, 5 females) with mean age 30 ± 2 years and mean BMI 25 ± 1 kg/m2 were recruited to the study. Using a non-blind, crossover design trial, the subjects consumed 50 (or 25) grams of available carbohydrate portions of glucose (standard food) and test foods after an overnight fast and their serum glucose levels were determined at 0, 15, 30, 45, 60, 90 and 120 minutes after the consumption of each test food. Glucose was tested on three separate occasions, and the test foods once. The GI value was calculated geometrically by expressing the Incremental Area Under the Blood Glucose Curve (IAUC) for the test foods as a percentage of each subject's average IAUC for the standard food. Results: The results indicated that the IAUC for Watermelon (95 ± 11) was significantly higher (p

BackgroundAnnona muricataL. was identified as a popular medicinal plant in treatment regimens among cancer patients in Jamaica by a previously conducted structured questionnaire. Ethnomedically used plant parts, were examined in this study against human prostate cancer cells for the first time and mechanisms of action elucidated for the most potent of them, along with the active phytochemical, annonacin.MethodsNine extracts of varying polarity from the leaves and bark ofA. muricatawere assessed initially for cytotoxicity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on PC-3 prostate cancer cells and the ethyl acetate bark (EAB) extract was identified as the most potent. EAB extract was then standardized for annonacin content using High-performance Liquid Chromatography - Mass Spectrometry (HPLC-MS) and shown to be effective against a second prostate cancer cell line (DU-145) also. The mode of cell death in DU-145 cells were assessed via several apoptotic assays including induction of increased reactive oxygen species (ROS) production, reduction of mitochondrial membrane potential, activation of caspases and annexin V externalization combined with morphological observations using confocal microscopy. In addition, the potential to prevent metastasis was examined via inhibition of cell migration, vascular endothelial growth factor (VEGF) and angiogenesis using the chorioallantoic membrane assay (CAM).ResultsAnnonacin and EAB extract displayed selective and potent cytotoxicity against the DU-145 prostate carcinoma cells with IC50values of 0.1 ± 0.07 μM and 55.501 ± 0.55 μg/mL respectively, without impacting RWPE-1 normal prostate cells, in stark contrast to chemotherapeutic docetaxel which lacked such selectivity. Docetaxel’s impact on the cancerous DU-145 was improved by 50% when used in combination with EAB extract. Insignificant levels of intracellular ROS content, depolarization of mitochondrial membrane, Caspase 3/7 activation, annexin V content, along with stained morphological evaluations, pointed to a non-apoptotic mode of cell death. The extract at 50 μg/mL deterred cell migration in the wound-healing assay, while inhibition of angiogenesis was displayed in the CAM and VEGF inhibition assays for both EAB (100 μg /mL) and annonacin (0.5 μM).ConclusionsTaken together, the standardized EAB extract and annonacin appear to induce selective and potent cell death via a necrotic pathway in DU-145 cells, while also preventing cell migration and angiogenesis, which warrant further examinations for mechanistic insights and validity in-vivo.

Hypertension has been for decades a major contributor to overall mortality and morbidity worldwide. This study was aimed towards evaluating changes in blood pressure in normotensive and L-NAME hypertensive induced rats subjected to treatment with a synthesized semicarbazone copper complex (CSCZ)**. CSCZ was synthesized from the reaction between di-2-pyridylketone semicarbazone (dpksc) and CuCl2.2H2O in refluxing ethanol and characterized from its spectroscopic and elemental analyses. The infrared and electronic absorption spectra are in accord with the proposed formulation of the complex. Animals were rendered hypertensive by oral administrations of Nω-nitro-L-arginine methyl ester (L-NAME) daily (dose 40 mg/kg body weight) for 5 weeks. Oral daily dosages (20 mg/kg body weight) of CSCZ was administered to the animals. A significant decrease in systolic blood pressure (SBP) at 132.91 ± 7.62 was observed in the L-NAME/CSCZ treated group (LCZ) when compared to the L-NAME group at 161.00 ± 5.34 while no significant changes were observed in heart rate (HR) and pulse pressure (PP). Treatment with CSCZ also seemingly normalised and prevented the development of L-NAME induced hypertension in the rats. A significant decrease in SBP and PP was also seen in the normotensive group treated with CSCZ at 91 ± 2.11 and 21.67 ± 1.43 respectively when compared to the control group at 130.63 ± 2.98 and 44.10 ± 5.15 respectively. These findings reveal the blood pressure lowering effects of CSCZ in normotensive rats and its ability to prevent L-NAME induced hypertension.

Aim: The effectiveness of nutritional supplementation on drug-seeking behavior of amphetamine-addicted rats during withdrawal was investigated using a biased conditioned place preference (CPP) paradigm. Method: Twenty-four male Sprague-Dawley rats exhibiting baseline preference for the black chamber during a 20-minute pre-conditioning exploration of the CPP box completed the study. On alternate days of an 8-day schedule, twelve rats (Group AMP) were randomly selected, given either amphetamine sulfate (5 mg/ml, i.p.) and confined to the white chamber; or vehicle (1 ml saline, i.p.) and confined to the black chamber. A significant increased percentage time spent and number of entries made by Group AMP to the drug-paired, white chamber on the test day confirmed amphetamine addiction. Group AMP subsequently received increasing doses of amphetamine over 6 days. Following acute drug withdrawal, their CPP performance was compared with that of vehicle treated rats (Group SAL). Groups AMP and SAL were equally divided and randomly assigned to animals fed chow reconstituted with the nutritional supplement (AMP-S and SAL-S) over 8 weeks or standard rat chow (AMP-N and SAL-N). CPP performances for all rats were determined blindly from video recordings following this period. Results: Nutritionally supplemented, amphetamine withdrawn rats (AMP-S) exhibited significantly decreased percentage entries and time spent in the white chamber (p < 0.05), indicating preference for the black chamber and diminished drug-seeking behavior. ANOVA revealed that after 8 weeks of dietary supplementation, AMP-S rats behaved like drug-na?ve, control animals. Conclusion: Drug-seeking behavior by amphetamine-addicted animals was eliminated after treatment with a nutritionally supplemented diet.

The effects of Salako nutritional supplements on cocaine-dependent Sprague Dawley rats was investigated. Rats were made cocaine-dependent using conditioned place preference (CPP) where craving was analyzed regularly. Cocaine metabolite levels were determined from blood samples. CYP450 3A4 isoenzyme activities were obtained using liver homogenate. Statistical analysis was done using SPSS one-way ANOVA and Duncans multiple range test. Results show that when cocaine use was discontinued, the supplements reduced craving of cocaine significantly. Blood plasma results showed higher benzoylecgonine equilibrium possibly indicating that the supplements aided the removal of stored cocaine metabolites which may have contributed to better management of craving in the rats. CYP450 3A4 isoenzyme activity was further enhanced by the supplements and is indicative of increased cocaine metabolism. The results indicate that the Salako nutritional supplements reduce craving caused by chronic cocaine administration by increasing the liver CYP450 3A4 isoenzyme activity, resulting in better plasma clearance.

Background: Fruits and vegetables, for their complex carbohydrates, dietary fiber and micronutrients, should form an essential part of every diet. In order to give good dietary advice to diabetic patients, it is necessary to know the glycemic index of foods commonly consumed locally. The objective of this study was to determine the glycemic index (GI) and glycemic load (GL) of commonly available and consumed June plum (Spondias dulcis), Otaheite apple (Syzygium malaccense), Pineapple (Ananas comosus), and Cucumber (Cucumis sativus) in Jamaica. Methods: Ten (10) healthy Jamaican subjects (5 males, 5 females) with mean age 30 ± 2 years and mean BMI 25 ± 1 kg/m2 were recruited to the study. Using a non-blind, crossover design trial, the subjects consumed 50 (or 25) grams of available carbohydrate portions of glucose (standard food) and test foods after an overnight fast. Their serum glucose levels were then determined at 0, 15, 30, 45, 60, 90 and 120 minutes after the consumption of each test food. Glucose was tested on three separate occasions, and the test foods once. The GI value was calculated geometrically by expressing the incremental area under the blood glucose curve (IAUC) for the test foods as a percentage of each subject's average IAUC for the standard food. Results: The results indicated that the IAUC for Pineapple (96 ± 15) and Otaheite apple (122 ± 29) were significantly higher (p < 0.05) than that of June plum (23 ± 6) and Cucumber (40 ± 14). Similarly the GI of Pineapple (80 ± 20) and Otaheite apple (64 ± 15) were significantly higher than June plum (13 ± 5) and Cucumber (21 ± 6). Conclusion: June plum, Cucumber, were shown to have low glycemic index values, whereas Otaheite apple was intermediate and Pineapple high.

Background: Due to the prevalence of diabetes in Jamaica, an understanding of the glycemic index (GI) and glycemic load (GL) values of beverages and food can aid dieticians in guiding consumers to choose sensibly. It is reported that consumption of low GI and GL foods may reduce the risk of type 2 diabetes, coronary heart disease and obesity. However, low GI snacks/food available to diabetic patients in Jamaica are very limited. This study was conducted to develop a low GI and GL vegetable drink that could be commercialized. Methods: Ten (10) healthy Jamaican subjects (5 males and 5 females) with mean age 30 ± 2 years and mean BMI 25 ± 1 kg/m2 were recruited to the study. Using a non-blind, crossover design trial, the subjects consumed equicarbohydrate amounts (25 g of total available carbohydrate) of the vegetable (beetroot – Beta vulgaris, cucumber – Cucumis sativus and carrot – Daucus carota) drink and twice glucose as reference food (25 g of total carbohydrate). Blood glucose was determined after overnight fasting (0 hours) and at 15, 30, 45, 60, 90 and 120 minutes after the consumption of each test food. The glycemic index (GI) value was calculated geometrically by expressing the incremental area under the blood glucose curve (IAUC) as a percentage of each subject's average IAUC for the standard food. Results: The GI and GL values of the vegetable drink were found to be 34 ± 10 and 4.4, respectively. As per the Food and Agriculture Organization, GI cut-off values are as follows: low 70 and for GL, low ≤ 10, medium 10 to 20 or high ≥ 20. Hence the vegetable drink could be classified under low glycemic food/ nutrient. Conclusion: Identification of beverages and other foods with low glycemic responses may have practical applications in controlling blood glucose levels. This study provides scientific evidence of the blood glucose response of the formulated vegetable drink. The complex carbohydrates in beetroot, carrot and cucumber may be responsible for the low postprandial glycemic response. This will lead to a low demand for insulin secretion from the pancreatic β cells, which are often impaired in type 2 diabetic individuals.

The effects that chronic cocaine administration (CCA) have on craving, cocaine metabolite concentrations and cytochrome P450 3A4 isoenzyme (CYP450 3A4) activities in Sprague-Dawley rats following the administration of Salako Nutritional Supplements (SNS) were examined. Five groups of fifty rats were used to assess the effect of the SNS following CCA. Craving was analyzed for each rat using a Conditioned Place Preference protocol. Blood samples were obtained at regular intervals and used to measure cocaine plasma metabolite levels. CYP450 3A4 activity was determined in the liver. Administration of the SNS reduced craving of cocaine significantly, upon discontinuing cocaine in the rats. Blood plasma analysis showing higher benzoylecgonine equilibrium and the CYP450 3A4 levels demonstrated that the SNS possibly aided in the removal of the stored metabolites indicative of increased metabolism of cocaine, enhanced by the Supplements. Results indicate that the SNS formulation reduces craving caused by CCA by increasing the liver CYP450 3A4 activity, resulting in better plasma clearance.

Moringa oleifera trees grow well in Jamaica and their parts are popularly used locally for various purposes and ailments. Antioxidant activities in Moringa oleifera samples from different parts of the world have different ranges. This study was initiated to determine the antioxidant activity of Moringa oleifera grown in Jamaica. Dried and milled Moringa oleifera leaves were extracted with ethanol/water (4:1) followed by a series of liquid–liquid extractions. The antioxidant capacities of all fractions were tested using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. IC50 values (the amount of antioxidant needed to reduce 50% of DPPH) were then determined and values for the extracts ranged from 177 to 4458 μg/mL. Extracts prepared using polar solvents had significantly higher antioxidant capacities than others and may have clinical applications in any disease characterized by a chronic state of oxidative stress, such as sickle cell anemia. Further work will involve the assessment of these extracts in a sickle cell model of oxidative stress.

A sapogenin-rich preparation from Jamaican bitter yam (Dioscorea polygonoides) has been shown to reduce blood cholesterol concentrations in hypercholesterolemic rats and mice. Also, diosgenin supplementation has been reported to have antilipemic effects in several animal species. We investigated potential mechanisms of the lipid-lowering actions of bitter yam and also whether the actions were mediated by diosgenin. Sprague-Dawley rats were fed a hypercholesterolemic diet (4% cholesterol) alone or with 5% bitter yam or 1% diosgenin supplementation for 6 weeks. The control group was fed normal rat chow. The serum lipid profile, fecal cholesterol concentration, and serum lipase activity were assessed at the end of the period. The induction of hypercholesterolemia was inhibited by coadministration of 5% bitter yam or 1% diosgenin in the diet. Serum lipid profiles were similar in rats fed bitter yam or diosgenin. The fecal cholesterol concentration was significantly (P < .01) higher in rats fed diosgenin compared to the cholesterol group. However, there was no corresponding elevation in the group fed bitter yam. Administration of bitter yam or diosgenin supplement significantly increased (P < .01) the serum lipase activity compared to the normal control and cholesterol groups. The cholesterol-supplemented diet inhibited normal gain in body weight over the period. This action was potentiated by diosgenin. The effects of the respective supplements on body weight were not completely explained by food consumption. Supplementation of the diet with Jamaican bitter yam may be therapeutically beneficial in the management of hypercholesterolemia.

Salmonella infection in bird species in Jamaica was studied. This revealed that very low prevalence of salmonellosis was found (0.32 %). Salmonella Yeerongpilly (newly reported in the country) was isolated from a bird collected at a bird aviary. This study showed that there was the presence of this Salmonella serovar in a Chinese owl (Columba livia domestica) in Jamaica. There were not published reports from Caribbean Islands of the presence of this serovar. Salmonella Yeerongpilly belongs to serogroup E1 and by molecular serotyping random amplification of polymorphic DNA (RAPD) fingerprinting belongs to A20, B17 and C21. This strain was isolated in Queensland Australia in the 1960s before the successful Salmonella eradication campaign. This study suggests that a larger investigation in pet birds as Salmonella carriers should be carried out in Jamaica. Mandatory screening or quarantine of birds entering the country should be institutionalized. Original Research Article British Microbiology Research Journal, 4(2): 167-172, 2014 168

Mercury toxicity leads to cell damage in many organs of the body. The authors comparatively examined the ability of different food additives with medicinal properties to protect against mercury (Hg) accumulation in the liver following different treatment interventions and modes of administration. Rats were fed on either 7% w/w Zingiber officinale, 7% w/w Garlic, 10% w/w Lycopersicon esculentum, or 5%, w/w Garcinia kola (all in rat chow), while Hg (10 ppm) was given in drinking water. The additives were administered together with the metals (group 2), a week after (group 3) or a week before metal exposure (group 4) for a period of six weeks. The metal accumulations in the liver were determined using an Atomic Absorption Spectrophotometer (AAS). All the additives significantly (p

The Jamaican bitter yam (Dioscorea polygonoides) contains various bioactive components that may increase oxidative stress in various tissues at relatively high concentrations. The present study therefore investigated the effects of bitter yam supplementation (5%) on the integrity of the liver and kidneys. Two mice strains (inbred C57BL/6 and transgenic C57BL/6-Tg(APOA1)1Rub/J) were used in the study. Each strain was divided into two groups. One group was fed a basal diet without supplementation, and the second group was fed a basal diet supplemented with the Jamaican bitter yam. The results revealed that the transgenic mice fed diets with and without bitter yam supplementation experienced significant increases in weight, when compared with inbred mice fed similar diets. Hepatoprotective effects were observed in transgenic mice known to possess high serum high-density lipoprotein (HDL). Oxidative stress was induced in mice fed diets supplemented with bitter yam at a concentration of 5%. Practical Application The Jamaican bitter yam possesses potent anti-diabetic and hypocholesterolemic properties due to its high levels of sapogenin. Currently, the tuber is consumed in rural areas mostly during times of drought. No toxicology data, however, exist for consumption of this yam species. This study provides information on the possible toxicity from overconsumption and paves the way for future studies to establish an effective consumption dosage. With its potent cholesterol-lowering capabilities, the Jamaican bitter yam can be exploited in the nutraceutical industry and for the development of other value-added products for everyday consumption such as baked goods and granola bars, giving them a hypocholesterolemic twist.

Aims: The aim of this study was to investigate the effectiveness of medication in the prevention of Salmonella in growing chickens. Material and Methods: All specimens were placed in an igloo with ice packs and transported to the laboratory for analysis. Bacteriological media obtained from Difco Laboratories Detroit MI U.S.A were used for the isolation and identification of Salmonella spp. Salmonella Serological typing was performed to determine the Salmonella serovar by standard procedures. Chickens were given a single dose of a wild-type multiresistant strain of Salmonella Typhimurium (resistant to many antibiotics including cloramphenicol and bactrim) by oral route (3x10 9 cfu/bird) as a challenge. Results: The effectiveness of some medications in the reduction of Salmonella infections in growing chicken revealed that none of the groups including the control group showed

Aim: This study was undertaken to determine the prevalence of Salmonella spp contamination in the Jamaican poultry industry and its environments. Materials and Methods: A total of 45 farms across 6 Jamaican parishes were selected for this study. A total of 6693 specimens from animals and the environment were investigated for the presence of Salmonella spp. All specimens were placed in an igloo with ice packs and transported to the laboratory for analysis. Bacteriological media obtained from Difco Laboratories Detroit MI U.S.A were used for the isolation and identification of Salmonella spp. Salmonella serological typing was performed to determine the Salmonella serovar by standard procedures. Results: This study revealed a low prevalence of Salmonella contamination/infection in both small and large entities in the poultry industry in Jamaica. The overall prevalence was 1 % (79 positive out of 6693 specimens). However, a higher prevalence of Salmonella was observed in the case of those operations which practiced “organic” poultry farming. It was shown that two Salmonella serovars including Augustenborg and Kentucky, identified Research Article British Microbiology Research Journal, 3(4): 461-469, 2013 462 during the study, are newly reported serovars in Jamaica. The sources of Salmonella infection varied from poultry itself to other species, such as rodents, pigs and insects. Improper disposal of broken eggs, wet bedding and other fomites contributed to Salmonella contamination. Conclusions: The results of the study indicate possibility of salmonellosis (zoonosis) in Jamaica, although the prevalence of Salmonella spp was low, and the need for improved quality of the food industry, animal care and human health to prevent salmonellosis.

The primary aim of this study was to investigate the effects of Ortanique peel polymethoxylated flavones extract (PMF(ort)) on organ function parameters in the serum of hypercholesterolemic and normal rats. Thirty Sprague-Dawley rats were fed high cholesterol diets supplemented with 1.5% PMF(ort) and niacin respectively for 49days. Hypercholesterolemic rats fed PMF(ort) had significant reductions in the activities of aspartate aminotransferase and alkaline phosphatase (69.12±3.34 and 87.22±8.42U/L respectively) compared to the untreated hypercholesterolemic group (118.61±4.85 and 132.62±10.62U/L respectively, p

Background and aim Zinc deficiency due to low intake or unavailability by bioactive compounds may lead to morphological changes in the intestines resulting in disruptions in gut function. This study aims to assess effects of phytic acid on gut morphology of rats. Methods Diets supplemented with sweet potato phytate extract were fed to Wistar rats in zinc-deficient and zinc-sufficient states for 4 weeks. Similar test animals also had diets supplemented with the commercially available sodium phytate salt (IP6) for comparison. At the end of the feeding period, body weights, feed intake and markers of intestinal function were assessed. Results Acute zinc deficiency adversely affected the glycocalyx, goblet and Paneth cells within the small intestine. This may eventually lead to compromisation of the gut's immune system and further reductions in its metabolic and absorptive capacity. This was further aggravated by sweet potato phytate extract consumption. IP6 supplementation on the other hand, increased surface amplification in the jejunum resulting in increased gut transit time and more efficient absorption of nutrients. Conclusions To minimize compromisation of the gut's immune, absorptive and metabolic functions, adequate zinc supplementation is necessary especially if foods rich in phytates are included in the diet. Supplementation of the diet with IP6 seems to offset some of these effects with maximum benefits observed if the diet is properly supplemented with essential minerals.

The primary aim of this study was to investigate the effects of ortanique peel polymethoxylated flavones extract (PMFort) on antioxidant enzymes activities and lipid peroxide levels in organs of hypercholesterolemic and normal rats. Thirty Sprague-Dawley rats were fed high cholesterol diets supplemented with 1.5% PMFort and niacin respectively for 49 days. Hypercholesterolemic rats fed PMFort had significant reductions in malondialdehyde levels in the liver and brain compared to untreated hypercholesterolemic control rats. This reduction also occurred in the brain of the rats fed niacin. The activities of catalase, glutathione reductase, transferase and peroxidase were significantly reduced in the spleen, brain and liver of hypercholesterolemic rats fed PMFort compared to control. The activities of these enzymes were only reduced in the brain and liver of rats fed niacin. The results would suggest that PMFort modulates hypercholesterolemia-associated organ injury and oxidative stress in rat organs. PMFort could therefore be a suitable candidate of natural origin for prophylactic and therapeutic treatment of hypercholesterolemia-associated oxidative stress and organ injury.

The cholesterol-lowering efficacy and possible mechanism of action of polymethoxylated flavones (PMFs) derived from Ortanique peel (PMFort) were evaluated in diet-induced hypercholesterolemic rats. Hypercholesterolemic and normal rats were fed diets containing PMFort and niacin for 49 days, after which several biochemical parameters were determined in the serum and organ samples. Diets containing 1.5% PMFort significantly reduced serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C) and triglyceride (TG) levels by 45%, 69%, 30% and 24%, respectively, and significantly increased serum high-density lipoprotein cholesterol (HDL-C) levels by 45% compared to the untreated hypercholesterolemic rats. Fecal cholesterol was also significantly increased (106%) by PMFort supplementation. Hepatic cholesterol was significantly reduced as well as the hepatic activity of HMG-CoA reductase in the PMFort supplemented group compared to the untreated hypercholesterolemic groups. The findings suggest that PMFort may be a potent hypocholesterolemic supplement that acts by reducing cholesterol synthesis as well as by increasing fecal cholesterol output. PRACTICAL APPLICATIONS The present study has several possible practical applications. The polymethoxylated flavones are found almost exclusively in citrus peel, which is usually discarded and is underutilized and contributes to solid waste in some countries. The results from this study as well as studies in the literature show that polymethoxylated flavones (PMFs) exhibit several important beneficial biological properties. The extract used in this study can be used to develop a wide range of nutraceutic and pharmaceutic products with hypocholesterolemic efficacy which may have possible applications as alternatives to lipid lowering drugs which display several adverse effects.

BACKGROUND: Declines due to Papaya ringspot virus (PRSV) are the primary constraint limiting production of papaya (Carica papaya L.) in tropical and subtropical regions. Given the lack of suitable sources of resistance in the genus, transgenic papayas carrying the coat protein gene of a local strain of PRSV were recently developed to manage the disease in Jamaica. For assurance of food safety, a 90 day subchronic whole-food feeding study in rats was conducted with transgenic and non-transgenic papayas. RESULTS: Male and female Wistar rats (N = 56) received diets containing transgenic or non-transgenic papayas at twice the equivalent of the average daily human consumption of fresh papayas. No adverse effects on animal behaviour or differences in body weight and organ weight between the animal groups (P < 0.05) were observed during the study. Necropsy at the end of the study indicated that neither pathological nor histopathological abnormalities were present in the liver and kidneys of rats in the control and treated groups. In addition, the levels of activity of plasma, liver and kidney acid and alkaline phosphatases and alanine and aspartate transaminases were comparable (P < 0.05). Although significant differences (P < 0.05) were found in the cholesterol and triglyceride levels in the plasma and liver among animals of the treated groups, overall the values were comparable to those of the control. CONCLUSION: The results suggest that consumption of transgenic papayas may not have adverse effects in rats as regards the parameters considered in this study. Copyright © 2008 Society of Chemical Industry

A comparative investigation of the interplay between starch botanical source, micromeritics and their functionality in formulated paediatric paracetamol granules for reconstitution was conducted using starches extracted from five local yam (Dioscorea spp.) species. Significant differences were observed in the physicochemical properties of the different starches studied (p0.05). The observed differences in paracetamol dissolution correlated well with the physicochemical properties of the starches. Granules formulated with Chinese yam and Bitter yam starches showed the fastest rate of paracetamol dissolution with T(80) of 2.2 and 2.6 min, respectively, at 2.5%w/w, and 3.75 and 4.00 min, respectively, at 10% w/w binder concentrations. Those formulated with Round leaf yellow yam starch had the slowest dissolution rate with T(80) of 4.5 and 8.75 min, respectively, at 2.5% and 10% binder concentrations. The results generally indicate a significant dependence of the rate of paracetamol dissolution from granules on starch surface tension, viscosity, swelling power and water binding capacity, particle size distribution, specific surface and porosity. These, in turn, were found to be starch botanic source-dependent suggesting careful consideration of botanic source when substituting one starch product for another in granule formulation.

A comparative investigation of the surface properties of starch powders from three species of yam ( Dioscorea spp.) was conducted, using corn starch BP as reference standard, with a view to assessing their usefulness as ingredients of tablets/capsule formulations. Significant differences were observed in the physicomechanical properties of the starches obtained from the various yam species. Granular diameter ranged from 5.4 μm (Chinese yam) to 34.5 μm (Round leaf yellow yam). Corn starch BP has a mean granular diameter of 12.3 μm. Chinese yam starch had the highest specific surface area (625.91 m 2 /kg) while Round leaf yellow yam had the lowest (117. 4 m 2 /kg); corn starch BP has a specific surface area of 232 m 2 /kg. The surface tension of the starch mucilage also varied significantly with Bitter yam having the lowest (44.56 mN/m) and Round leaf yellow yam the highest (54.00 mN/m); corn starch had a surface tension of 62 mN/m. X-ray powder diffraction revealed three distinct crystalline patterns: Bitter yam and corn starch displayed the type A while Round leaf yellow yam and Chinese yam displayed the types B and C patterns respectively. In moisture adsorption, all the starches studied displayed monolayer adsorption profiles with rate order of moisture adsorption ranging from 0.92 mg%/h for Chinese yam to 1.07 mg%/h for Round leaf yellow yam starch. Since co-formulated materials will react or interact at the interface, the variations observed in the surface properties suggest a potential for significant botanical specie-dependent differences in performance of starch powder in formulated dosage forms.

PurposeThis study aims to investigate the levels of some anti‐nutritional factors and minerals and the effect of boiling or roasting on selected commonly consumed Caribbean tuber crops.Design/methodology/approachThree commonly consumed tuber crops in the Caribbean namely: Yellow yam (Dioscorea cayenensis), Cocoyam (Xanthosoma sp.) and Sweet potato (Ipomea batatas) were harvested from farmers’ field in the Parish of Manchester, Jamaica and assessed in their boiled, raw and roasted forms for levels of some anti‐nutritional factors and minerals.FindingsZinc and iron levels were highest in raw Yellow yam, while the highest levels of calcium were observed in Sweet potato. The phytic acid to zinc molar ratio was higher than 15 in all the tuber crops in their raw and roasted forms. Boiling reduced this ratio to below 15 for Yellow yam and Cocoyam but still remained above 15 for Sweet potato. Cyanoglucoside level was highest in raw Sweet potato followed by Yellow yam and Cocoyam. Boiling or roasting reduced the levels of cyanoglucosides. Roasting greatly lowered the level of trypsin inhibitor activity compared to boiling. The highest level of trypsin inhibitor activity was recorded in the raw tubers, and slight reductions were observed upon processing.Practical implicationsTrypsin inhibitor was more stable to heat treatment compared to similar tubers grown in Africa. It may be beneficial to isolate and characterize trypsin inhibitor in these Caribbean tuber crops for utilization in nutraceutics.Originality/valueThis study shows that the two traditional processing methods were effective in lowering the levels of anti‐nutritional factors.

A comparative investigation of the fundamental and derived properties of starches from some species of yam (Dioscorea spp.) was conducted with a view to establishing their suitability as excipients in tablet and capsule formulations. Variations were observed in the mean granular diameter of the starches obtained from the different Dioscorea species. Granular diameter ranged from 5.4 μm (Chinese yam) to 34.5 μm (Round leaf yellow yam). Chinese yam and Bitter yam had the highest specific surface area (625.91 m 2 /kg and 258.76 m 2 /kg, respectively) while Round leaf yellow yam and Negro yam had the lowest (117.4 m 2 /kg and 154.34 m 2 /kg, respectively). Chinese yam had the lowest granular volume (6.00 μm 3 ), surface area (5.67 μm 2 ) and granule surface-mean diameter (6.74 μm), while Round leaf yellow yam had the largest mean granular diameter, highest granular volume (35.2 μm 3 ), surface area (34.8 μm 2 ) and granule surface mean diameter (35.88 μm). Particle size distribution plots of Chinese yam, Round leaf yellow yam and Negro yam displayed a Gaussian size distribution pattern while Bitter yam displayed a negatively skewed distribution. The variations observed in the granular size and shape may influence the observed derived properties of the starches.

The concentrations of the polymethoxylated flavones (PMFs) in peels of selected citrus cultivars grown in Jamaica and Mexico were determined. The PMFs were extracted from sun-dried citrus peels with reagent-grade methanol. Analyses were carried out by reverse-phase HPLC and UV detection. The column used was a C(18) 5 microm (150 x 4.6 mm) Discovery column. Elution was in the gradient mode, using a ternary mobile phase. The results showed that all the citrus cultivars used contained at least three of the six major PMFs quantified. Ortanique peel contained the highest quantity of PMFs (34,393 +/- 272 ppm), followed by tangerine (28,389 +/- 343 ppm) and Mexican sweet orange (sample 1; 21,627 +/- 494 ppm). The major PMFs, i.e. sinensetin, nobiletin, tangeretin, heptamethoxyflavone, tetramethylscutellarein and hexamethyl-o-quercetagetin, present in the peels of 20 citrus cultivars, was quantified. The results were compared with those of Florida citrus peels. A large amount of citrus peels and byproducts are produced in the Caribbean which could provide a cheap and convenient source of PMFs.

Two wild (Dioscorea polygonoides and Rajana cordata) and seven cultivated varieties of Jamaican yams (Dioscorea spp.) were analyzed for their proximate composition and the levels of antinutritional factors. The protein level range was 47.8 +/- 2.6 to 88.0 +/- 2.5 g/kg dry weight. The lowest level was seen in D. cayenensis. The range for the dietary fiber content in the tubers was 16.3 +/- 0.7 to 63.5 +/- 0.4 g/kg dry weight. The wild yam varieties recorded higher levels. Saponins level was

In this study, phytic acid was extracted from Jamaican sweet potato, which has been reported to contain a high phytic acid to zinc ratio and fed to Wistar rats for three weeks. Animals were then sacrificed and blood glucose, intestinal amylase activity and faecal minerals were determined. Blood glucose levels in all the groups fed phytic acid extract from sweet potato or commercial phytic acid were reduced compared to their controls. This lowering was more pronounced in the groups fed phytic acid extract from sweet potato or commercial phytic acid plus zinc supplement. Faecal zinc was significantly higher in the groups fed phytic acid extract from sweet potato compared to the controls in weeks 1 and 2. Supplementation of the diets with phytic acid extract from sweet potato or commercial phytic acid resulted in an increase in the faecal output of iron except for the group that was fed commercial phytic acid plus zinc. Overall, the supplementation of the rat diet with phytic acid extract from sweet potato resulted in a general increase in the output of these faecal minerals.

Starch granules from Round leaf yellow yam, Negro yam, Sweet yam, Bitter yam and Chinese yam grown in Jamaica were isolated and characterized. The amylose content, granular size, crystallinity, and digestibility by α-amylase were determined. The granules obtained were of three crystalline types. Round leaf yellow yam, Negro yam and Sweet yam were found to be type-B, while Chinese yam and Bitter yam were type-C and type-A, respectively. Round leaf yellow yam had the highest amylose content (26.5%) while Chinese yam had the lowest (11.1%). The granule size varied between 1–3 μm for Chinese yam and 16–42 μm for Round leaf yellow yam. Significant variations in digestibility of the granules were observed. Raw starches from Chinese yam and Bitter yam were the most susceptible to α-amylase digestion (porcine pancreatic α-amylase, pH 5.5, 0.02% CaCl2, 40°C, 24 h) with 21.27 ± 0.01% and 18.11 ± 0.02% degradation, respectively, while Round leaf yellow yam, Negro yam and Sweet yam starches were the least susceptible, with 13.74 ± 0.03%, 14.98 ± 0.08%, and 15.32 ± 0.04% enzymatic degradation, respectively.

In this study, the effect of yam steroidal sapogenin extract on intestinal morphology in streptozotocin-induced diabetic rats was examined. Diabetic male Wistar rats (n = 32) were fed diets supplemented with 1% bitter yam steroidal sapogenin extract or commercial diosgenin for three weeks. The effect on intestinal morphology was assessed. The induction of diabetes significantly increased villus length and crypt depth compared to the normal group. Supplementation of the diet with sapogenin extract or commercial diosgenin significantly increased villus width compared to the diabetic controls. The dietary supplements also significantly decreased crypt depth towards that of the normal controls. This study shows that the feeding of bitter yam steroidal sapogenin extract to diabetic rats may result in alterations in the intestinal morphology.

The development of plants capable of growing under saline conditions is one approach at utilizing saline soils that are otherwise arable. This study was designed to develop salt-tolerant yam (Dioscorea alata) plantlets, using tissue culture techniques. Salt-tolerant yam (Dioscorea alata cv. Sweet yam) plantlets were produced in vitro through repeated culturing and selection on saline media. Two hundred plantlets were subcultured on normal multiplication media (Murashige and Skoog basal media with 30 gl−1 sucrose and 0.44 μM benzylaminopurine). A further 400 plantlets were equally subcultured on multiplication media supplemented with 100 or 200 mM NaCl. Plantlets that proliferated on medium with 100 mM saline conditions were repeatedly subcultured on saline media. Growth of plantlets and root formation were assessed along with some biochemical parameters such as invertase (EC 3.2.1.26), peroxidase (EC 1.11.1.7), and polyphenol oxidase (EC 1.10.3.1) activities. No growth was observed for plantlets transferred to the highly saline media of 200 mM NaCl and the explants did not survive beyond 6 wk. Control plantlets exhibited 100% rooting within 3 wk compared to 5 wk for plantlets on 100 mM NaCl. Development of new nodes and leaves were observed for plantlets on 100 mM NaCl, although at an initially slower rate than the control plantlets. The enzyme activity profiles obtained for plantlets on 100 mM NaCl reflected the biochemical adjustments of the plantlets to cope with the saline conditions. This was further substantiated by the detection of two reproducible bands of sizes 1 and 0.35 kb from reverse transcription polymerase chain reaction (RT-PCR) studies of salt-tolerant yam plantlets. These results can be translated into efforts aimed at maximizing the use of saline soils.

Bitter yam ( Dioscorea polygonoides ) steroidal sapogenin extract and commercial diosgenin were administered to diabetic rats for 21 days. Plasma glucose and lipids were assessed. Liver lipid distributions were also determined. The two dietary supplements fed to diabetic rats resulted in significant decreased body weight gain. The test diets significantly lowered plasma glucose and total cholesterol. Sapogenin extract supplement significantly lowered plasma total triglycerides. Plasma and liver VLDL+LDL-cholesterol were significantly reduced while the HDL fraction was increased in diabetic rats fed the test supplements. These results showed that the consumption of the two supplements maybe useful in the management of hypercholesterolemia often associated with diabetes.

The effect of the section of yam (Dioscorea cayenensis) tuber used as planting material in minisett on the biochemical properties of the resultant tuber was studied. The biochemical parameters invertase (EC 3.2.1.26), acid phosphatase (EC 3.1.3.2), peroxidase (EC1.11.1.7), polyphenol oxidase (EC 1.10.3.1), total sugars and starch were evaluated in tubers resulting from field-grown and tissue culture-derived setts of the cultivars Roundleaf and Blackwiss yellow yams. No significant differences were observed between tubers resulting from field-grown and tissue culture-derived setts relative to the parameters studied. Invertase activity was found to be highest in tubers from middle-derived setts, while tail-derived setts had the lowest activity for both cultivars. Middle-derived tubers were also found to have significantly higher levels of acid phosphatase activity and starch content. However, middle-derived tubers had the lowest level of total sugars. Polyphenol oxidase and peroxidase were also found to be significantly higher in tubers from middle-derived setts. These results suggest a higher rate of active starch formation in tubers from middle-derived setts. © 2002 Society of Chemical Industry

The Jamaican Round-Leaf yellow yams (RLY2), Dioscorea cayenensis, are edible tubers, bulbils or rhizomes that are of considerable economic value and possess several health benefits. These RLY2 are a rich source of anti-oxidants, vitamins and phytochemicals. In addition to its nutritional value, the Jamaican populace regards RLY2 as an herbal medicine useful in treatment of diabetes mellitus, hypertension and certain kind of cancers. Chemical analysis of RLY2 revealed the presence of a myriad of bioactive ingredients that are likely to be lost due to the method of preparation for consumption. Thus, we hypothesized that mild extraction of RLY2 will preserved the bioactive analytes that give RLY2 its anti-cancer property. To test this hypothesis, different ethanolic extracts of RLY2 were prepared, and their bioactivity demonstrated in two models of prostate cancer. The present study demonstrates dosage and time-dependence inhibition in both the androgen sensitive LNCaP and androgen insensitive DU-145 prostate cancer cell lines. We observed that DU-145 was three-times more sensitive to RLY2 ethanol extract than LNCaP. Growth of LNCaP for 3-days with varying concentration of RLY2 ethanol extract resulted in an IC50 of 750 ppm (95% C.I. 726-791ppm), whereas DU-145 resulted in an IC 50 of 250 ppm (95% C.I. 236-281ppm). The maximum growth inhibition by RLY2 extract occurs within twenty-four hours for both LNCaP and DU-145 with no significant changes after 5-days. To determine the mechanism of toxicity by RLY2, we induced both LNCaP and DU-145 with RLY2 for 0-24h and prepared cells for flow cytometer analysis. The effect of RLY2 on cell cycle and degree of apoptosis will be discussed. Our data indicated that the ethanol extract of RLY2 was more sensitive toward androgen-insensitive prostate cancer. Thus, this study suggests that RLY2 contain bioactive chemical that may be used in grade II prostate adenocarcinoma represented by the DU-145 phenotype. Citation Format: Sasha-Gay A. Wright, Wesley G. Gray, Helen Asemota. Anti-cancer activity of extract from the Jamaican round-leaf yellow yam (RLY2) (Dioscorea cayenensis) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 197. doi:10.1158/1538-7445.AM2017-197

We reported that Jamaican bitter yam (Dioscorea polygonoides) has antilipemic potential in rats; however there is limited data on the toxicological profile of the yam. We therefore investigated the effects of bitter yam consumption for 6 or 12 weeks on renal and hepatic function in rats fed a high (4%) cholesterol diet.Twenty four rats were divided into six groups (n = 4); three of which were used for each investigation (6 or 12 weeks). One group was administered 4% cholesterol diet, while the yam group had the cholesterol diet supplemented with 5% bitter yam. The control group was fed standard rat chow. Liver and kidney function tests were performed on serum, liver and kidney. Histological studies were conducted on liver samples. Acute toxicity tests were performed in rats and mice administered a single high dose of bitter yam (10 g/kg).Activities of liver and kidney AST and ALT differed (p ≤ .02) between control rats and those fed cholesterol with bitter yam for 12 weeks. Albumin to globulin ratio was reduced (p = .03) in rats fed cholesterol with bitter yam for 6 weeks as compared to the control group. Serum urea concentration was higher (p.05) in rats fed bitter yam as compared to normal chow for 6 weeks. The cholesterol diet caused extensive fat deposition in liver cells; however this was inhibited by co-administration of bitter yam.Long-term administration of Jamaican bitter yam may induce slight changes in renal and hepatic functions.

We have used random amplified polymorphic DNA (RAPD) analysis to characterize eleven cultivars of the five economically most important yam species grown in Jamaica (Dioscorea alata, D. cayenensis, D. rotundata, D. trifida and D. esculenta). Amplification of genomic DNA samples with nine different arbitrary 10mer primers revealed a total of 338 different band positions, ranging in size from 0.3 to 2.5 kb. RAPD patterns proved to be highly reproducible and somatically stable. While no variation was observed among plants belonging to the same cultivar, a large number of intervarietal and interspecific polymorphisms enabled us to reliably discriminate between all Jamaican cultivars investigated.

Factors such as inorganic ammonium, growth regulator supplements, propagule type and subculture period affecting the in-vitro establishment of Dioscorea cayenensis and D trifida have been examined. The results indicate that for D cayenensis, transfer of whole plantlets to fresh initiation media prior to cutting into nodal segments and transfer to establishment media was beneficial. Addition of 800 mg litre−1 NH4NO3 to basal medium (BM) containing 0.5 mg litre−1benzylamino purine (BAP) caused a significant improvement in nodal numbers and resulted ir. 11.8 propagules per original explant after 8 weeks or 184.1 propagules after 16 weeks in-vitro. Rapid establishment of D trifida cv Short Neck Yampie depended on the original explant source. Explants obtained from small tuber vines grew faster on establishment than those obtained from leafy cuttings. Initiation on BM supplemented with 0.5 mg litre−1 kinetin (BM0.5K) and establishment on BM supplemented with 0.5 mg litre−1 BAP (BM0.5BAP) produced the optimum result for the vines obtained from small tubers (24.0 propagules after 8 weeks of culture). For explants obtained from leafy cuttings, initiation on BM0.5BAP and establishment on BM0.5K gave optimum results (15.8). Quick establishment of initiated plantlets shown by increased shoot response and high multiplication rates were achieved in this study.

Explants of tuber, meristem and vines from three widely cultivated yam species in Jamaica-D cayenensis, D rotundata and D trifida-were examined for their responses to mineral media strength, inorganic ammonium and growth regulator supplements. Tuber pieces (5 mm 3 ) showed some positive growth responses but did not produce in-vitro plantlets on all the media tested. Meristem tips of D trifida grew rapidly on basal media (BM) supplemented with either 0.1 mg litre -1 6-benzylamino purine (BAP) and 0.01 mg litre -1 indole butyric acid or 0.2 mg litre -1 BAP and 1.0 mg litre -1 naphthalene acetic acid (NAA) producing plantlets by 28 weeks. The nodal explants grew rapidly with plantlets obtained from all the cultivars within 4 weeks. Use of young, vigorously growing vines of 8 weeks or less, as explant source, gave low contamination levels (16-25%) in culture when sterilised for 30 min in 200 g litre -1 NaOCl in the case of D trifida and 300 g litre -1 NaOCl in the case of D cayenesis prior to culturing. Initiation of growth was optimal when explants were taken from monopodial vines grown in October or January and placed on BM supplemented with 0.5 mg litre -1 BAP (BM0.5BAP). Addition of 0.5 mg litre -1 kinetin to the BM or 0.05 mg litre -1 NAA to BM0.5BAP depressed shoot production, while 50 mg litre -1 kinetin increased swelling of the nodal region in explants from sympodial shoots and from vines grown in March. The results suggest that nodal segments excised from young, fast growing vines of these species are the best explant source for the purpose of commercial micropropagation

Background and aim: Studies have shown that polymethoxylated flavones have potent hypolipidemic properties. There are, however, gaps in the literature on their effects on organ structures. This study evaluated the histopathological effects of Ortanique peel polymethoxylated flavones extract (PMFort) on the organ structures of diet-induced hypercholesterolemic rats. Methods: Thirty Sprague–Dawley rats were fed normal rat chow as well as high cholesterol diets supplemented with PMFort and niacin, respectively. Light microscopic evaluation of the liver, spleen, kidney and bowel of hypercholesterolemic rats fed PMFort and niacin was performed to determine possible morphologic alterations, compared to untreated hypercholesterolemic rats. Results: Untreated hypercholesterolemic rats showed significantly altered intestinal morphology, with an increase in the number of absorptive cells and in villus length when compared to untreated normal rats. They also exhibited hepatic steatosis (100%) and inflammation (20%) and lymphoid hyperplasia of the spleen (33%). Hypercholesterolemic rats treated with 1.5% PMFort showed reductions in absorptive cell number, villus length and hepatic steatosis compared to the untreated hypercholesterolemic rats. They also showed significant reduction in splenic lymphoid hyperplasia. Conclusions: The current results would suggest that PMFort consumption has no toxic effects on the organs of hypercholesterolemic rats but may ameliorate hypercholesterolemia-associated alterations in organ structures.

Dioscorea yam tubers of 11 cultivars from five common species grown in Jamaica were analysed for the following: protein content, total phenolics, vitamin C, total lipids, fatty acid composition and activity of the polyphenol oxidase enzyme. The results show that the yams grown in Jamaica are of good nutritional value with considerable amounts of protein, vitamin C, low lipids with only one cultivar ‘renta yam’ (D alata) possessing high levels of phenolic compounds. The fatty acids present in the total lipid extracts show that yam tubers generally possess high levels of saturated fatty acids mainly palmitic acid. However, the species D alata (cv white yam) and the species D trifida (cv yampie) have high levels of the unsaturated fatty acid, linolenic. All the polyphenol oxidases from the 11 cultivars show activities towards the diphenol substrates, catechol and DL-DOPA (DL-3,4-dihydroxyphenylalanine). However, no oxidation was observed with L-tyrosine, a monophenol substrate. All cultivars studied were found to have different lengths of dormancy which varied with storage conditions. When the harvested tubers were washed, sunned and stored at 20†C in a dark cupboard, it was possible to extend their lengths of dormancy by a further 11 weeks.

The effect of short-term storage on the protein, phosphorus and phenolic content as well as peroxidase and o-diphenolase activities of cut, harvested Jamaican yam (Dioscorea sp) tubers (D rotundata. D alata and D cayenensis) was studied. There was an initial increase in the total phenolic content up to the third week of storage followed by a gradual decrease to the sixth week. Phenolic content was found to be highest in D cayenensis followed by D rotundata and D alata. The activities of peroxidase (EC 1. 11. 1. 7) and o-diphenolase (EC 1. 10.3.1) increased steadily up to the third week of storage and thereafter decreased to the fifth week. The intensity and rapidity of browning in tubers when cut, correlated very closely with the tuber o-diphenolase and phenolic content levels while the onset of rotting correlated with the peroxidase activity levels in the species studied.

Transformation of agricultural crops with novel genes has significantly advanced disease-resistance breeding, including virus resistance through the expression of virus sequences. In this study, the effects of long-term, repeated exposure to transgenic papayas carrying the coat protein gene of Papaya ringspot virus and conventional non-transgenic papaya on the histology and selected biochemical parameters of the intestinal tract were compared. For 3 months, male and female Wistar rats received diets containing transgenic or non-transgenic papaya at twice the equivalent of the average daily consumption of fresh papayas. Gross and macroscopic appearance of intestinal tissues, as well as stomach tissues, was comparable (P

This article reports the first electrochemical characterization of pain biomarkers that include arachidonic acid (AA), prostaglandin G(2) (PGG(2)), and cyclooxygenase 2 (COX-2). These biomarkers are mediators of pathophysiology of pain, inflammation, and cell proliferation in cancer. The article also reports the development of an electrochemical immunosensor for monitoring these pain biomarkers. The results revealed that direct electron transfer between AA metabolites and the electrode could be easily monitored and that an enzyme-modified electrode dramatically enhanced bioelectrocatalytic activity toward AA. Cyclic voltammetric analysis of AA revealed a concentration-dependent anodic current with a slope of 2.37 and a limit of detection (LOD) of 0.25nM. This unique AA/gold electrode electron transfer provides a good electrochemical sensing platform for prostaglandin H(2) (PGH(2)) as the basis for quantitation of pain. An amperometric signal intensity of a COX-2 antibody-modified gold electrode was linear with COX-2 concentration in the range of 0.1-0.5microg/ml and an LOD of 0.095microg/ml. The results also revealed a linear correlation of the concentration of PGG(2) with an LOD of 0.227microM.

Phytic acid was extracted from sweet potato (Ipomoea batatas) and fed to Wistar rats with or without zinc for 3 weeks. Animals were then sacrificed and bone and faecal minerals were assessed. The ultra-structure of the bones was examined via scanning electron microscopy. Phytic acid extract or commercial phytic acid supplemented diets (D + Zn + PE or D + PE) displayed reduced bone calcium levels (101.27 +/- 59.11 and 119.27 +/- 45.36 g/kg) compared to the other test groups. Similarly, reduced calcium were observed in the control groups (D + Zn and D) fed formulated diets with or without zinc supplementation (213.14 +/- 15.31 and 210 +/- 6.88 g/kg) compared to the other test groups. The group fed supplemented commercial phytic acid diet (D + CP) demonstrated the lowest femur magnesium (3.72 +/- 0.13 g/kg) while the group fed phytic acid extract supplementation (D + PE) recorded the highest level (4.84 +/- 0.26 g/kg) amongst the groups. Femur iron was highest in the group fed commercial phytic acid supplemented diet (D + CP -115.74 +/- 2.41 g/kg) compared to the other groups. Faecal magnesium levels were significantly higher in the two test groups fed phytic acid extract with or without zinc (D + Zn + PE or D + PE) compared to all other groups. All the groups which had phytic acid supplemented diets had significantly thinner bone in the trabecular region, compared to the groups fed formulated diet or zinc supplemented formulated diet (D or D + Zn). These observations suggest that the consumption of foods high in phytic acid may contribute to a reduction in the minerals available for essential metabolic processes in rats.