Tetrahydrobiopterin (H 4 B) is a critical element in

This study assessed the melatonin content of six tropical fruits and examined whether human consumption could contribute to dietary melatonin as measured by 6-sulfatoxymelatonin (aMT6-s, a marker of circulating melatonin in the body). Melatonin was extracted using methanol and analyzed by high-performance liquid chromatography. In a clinical crossover study, 30 healthy volunteers consumed selected fruits one at a time, with a 1week wash-out period between fruits, until completing all six fruits. Most fruits had moderate melatonin content. Significant increases in urine aMT6-s concentrations were seen after the consumption of pineapple (266%, p = 0.004), banana (180%, p = 0.001), and orange (47%, p = 0.007). The need to analyze melatonin both in fruit and as in vivo uptake was demonstrated. Further study is warranted regarding the clinical effect of fruit consumption in people with age-related melatonin reduction problems such as sleeplessness and illnesses involving oxidative damage.

Twenty-eight herbal medicinal products from Thailand were investigated for aflatoxin (AF) contaminations by employing a specific HPLC assay for the determination of AFB1, B2, G1 and G2. The samples were extracted with 80% (v/v) methanol in water before further cleaned up with an immunoaffinity column and followed by the detection of AFs by using an electrochemically post-column derivatization with iodine and fluorescence detector. The extraction procedure was optimized in order to obtain the best recovery. The method was successfully carried out with all the herbal products diversified as to compositions and dosage forms. The results revealed that five (18%) of herbal samples were contaminated with detectable amount of the total AFs ranging from 1.7 to 14.3 ng/g. The association between particular herbal/plant and the AF contaminated could not be determined due to the low frequency of positive samples. The contaminated products were those in tablet (4) and capsule (1) dosage forms. It was possible that the original fungal infection of these products may have been derived from either the crude herbal or other ingredients making these preparations, such as starch. In conclusion, none of the AF contaminated level found was above the current legislative level permissible in Thailand (20 ng/g). A word of caution, however, exporting some high AF-contaminated herbal products to countries where more stringent permissable level of aflatoxins exist could result in trade Barriers.

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A correlation between endogenous hemin and pro-oxidant activity was revealed in serum of beta-thalassemia/hemoglobin E disease (beta-thal/Hb E), which is the most common prevalent type of thalassemia in Thailand. The technique of low temperature electron spin resonance spectroscopy was used for characterization and quantification of high spin ferric heme, which had been identified as hemin (iron (III)-protoporphyrin IX). Hemin was present at levels ranging from 50 to 280 microM in serum of beta-thal/Hb E but not detectable in serum of non-thalassemia. Pro-oxidant activity in serum of beta-thal/Hb E was demonstrated by luminol-mediated chemiluminescence, a sensitive method for screening of free radical generation in vitro. In the presence of H2O2, the chemiluminescence intensity (CL) was about 20 fold enhanced in serum of beta-thal/Hb E, indicating its extensive pro-oxidant activity. The CL showed a good correlation with serum heroin, r = 0.778 (p < 0.001), while the correlations with total serum iron and serum ferritin were 0.260 (p = 0.259) and 0.519 (p = 0.004), respectively. Our finding suggested that serum hemin readily catalyzed free radical reactions and it may contribute a major pro-oxidant in blood circulation of beta-thal/Hb E.

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In the previous study, we have found that the cordycepin which was extracted from Cordyceps mycelia produced by growing Cordyceps militaris on the dead larva of Bombyx mori silkworms showed the anti-proliferative effect toward lung cancer cells without toxicity to non-cancer cells. In this work, the cordycepin was tested for its in vitro mutagenicity and in vivo toxicity. From the Ames test and subacute toxicity test using oral administration in a rat model, the cordycepin was proved to be a non-mutagenic and non-toxic compound. The hematology and blood chemistry as well as the microanatomical characteristic of the tissues of rats fed with cordycepin every day for consecutive 30 days were comparable to those of the normal ones. Then, the cordycepin was incorporated in gelatin type A (GA) and gelatin type B (GB) nanoparticles aimed to sustain its release and activity. The cordycepin incorporated in both GA and GB nanoparticles showed the sustained release profiles. GA nanoparticles could encapsulate cordycepin at higher encapsulation efficiency due to the attractive electrostatic interaction between the positive-charged GA and the negative-charged cordycepin. However, GA nanoparticles released cordycepin at the higher amount possibly because of the large surface area of small size nanoparticles. Comparing to GB nanoparticles, the higher amount of cordycepin released from GA nanoparticles showed the higher anti-proliferative and anti-migratory effects on A549 lung cancer cells. In conclusion, GA nanoparticles were suggested as a suitable carrier for the sustained release of cordycepin. The GA nanoparticles releasing cordycepin could be an effective and non-invasive material for the treatment of lung cancer cells.