Effects of ionizing radiation on bio-active plant extracts useful for preventing oxidative damages.

Humans are exposed to ionizing radiations in medical radiodiagnosis and radiotherapy that cause oxidative damages and degenerative diseases. Airplane pilots, and even more astronauts, are exposed to a variety of potentially harmful factors, including cosmic radiations. Among the phytochemicals, phenols are particularly efficient in countering the oxidative stress. In the present study, different extracts obtained from plant food, plant by-products and dietary supplements, have been compared for their antioxidant properties before and after irradiation of 140 cGy, a dose absorbed during a hypothetical stay of three years in the space. All the dry extracts, characterized in terms of vitamin C and phenolic content, remained chemically unaltered and maintained their antioxidant capability after irradiation. Our results suggest the potential use of these extracts as nutraceuticals to protect humans from oxidative damages, even when these extracts must be stored in an environment exposed to cosmic radiations as in a space station.

Consumption of vitamin D2 enhanced mushrooms is associated with improved bone health.

Mushrooms are the best nonanimal food source of vitamin D2. Pulsed irradiation can enhance vitamin D2 in mushrooms quickly. We investigated the effect of supplementing high vitamin D2Pleurotus ferulae mushrooms in a mouse model of osteoporosis. Thirty-two female C57BL/6JNarl mice were divided into four groups including sham, ovariectomized (OVX), OVX+nonpulsed mushroom (NPM) and OVX+pulsed mushroom (PM). After 23 weeks of treatment, serum samples were analyzed for osteoblast and osteoclast indicators, as well as metabolites using NMR spectroscopy. To examine bone density, femurs were analyzed using micro-computed tomography. The NPM and PM treatment mice showed increased bone density in comparison with OVX mice. In addition, the PM mice showed higher osteoblast and lower osteoclast indicators in comparison with OVX mice. Serum metabolomics analysis indicated several metabolites that were different in PM mice, some of which could be correlated with bone health. Taken together, these results suggest that pulsed irradiated mushrooms are able to increase bone density in osteoporotic mice possibly through enhanced bone metabolism. Further studies in humans are needed to show their efficacy in preventing osteoporosis.

Study of the photocatalytic transformation of synephrine: a biogenic amine relevant in anti-doping analysis.

The occurrence of some cases of positive results in anti-doping analysis of octopamine requires clarification as to whether its methylated derivative synephrine could be a metabolic precursor of octopamine itself. Synephrine is a natural phenylethylamine derivative present in some food supplements containing Citrus aurantium, permitted in sport regulations. A simulative laboratory study had been done using a photocatalytic process, to identify all possible main and secondary transformation products, in a clean matrix; these were then sought in biological samples obtained from three human volunteers and four rats treated with synephrine; the parent compound and its new potential metabolic products were investigated in human urine and rat plasma samples. The transformation of synephrine and octopamine and the formation of intermediate products were evaluated, adopting titanium dioxide as photocatalyst. Several products were formed and characterized using the HPLC-HRMS(n) technique. The main intermediates identified in these experimental conditions were compared with the major synephrine metabolites found in in vivo studies on rats and humans. Some more oxidized species, already formed in the photocatalytic process, were also found in urine and plasma samples of treated animals. These new findings could be of interest in further metabolism studies. The main photocatalytic pathway involving synephrine appears to be N-demethylation to give octopamine. On the contrary, we demonstrate the inconsistency of this reaction in both rat and human in vivo determinations, resulting in forensic importance.

Degradation kinetics of malvidin-3-glucoside and malvidin-3,5-diglucoside exposed to microwave treatment.

Understanding the factors that contribute to the degradation of bioactive compounds during microwave treatment is meaningful for the practical application of this novel technology. The influence of microwave power, energy density, temperature, pH value, and initial concentration of anthocyanins (Acys) on the degradation behavior of malvidin-3-glucoside (Mv-3-glu) and malvidin-3,5-diglucoside (Mv-3,5-diglu) was investigated in this study. Results showed that the degradation of both Acys was accelerated with the increase of microwave power, energy density, temperature, pH value, and initial concentration of Acys. The degradation process of both Acys followed the first-order kinetics model (R² > 0.94), whereas the relationship between Acys degradation and energy density fitted to the logistic model well (R² > 0.98). In addition, Mv-3-glu was more susceptible to the microwave treatment than Mv-3,5-diglu. Compared with heating in a 98 ± 2 °C water bath, both Acys degraded more rapidly under microwave treatment at 100 °C, indicating the occurrence of microwave effect. The results provide a guide for the scientific application of microwave treatment.

Novel solid self-emulsifying drug delivery system of coenzyme Q10 with improved photochemical and pharmacokinetic behaviors.

The present study was undertaken to develop a solid self-emulsifying drug delivery system of coenzyme Q(10) (CoQ(10)/s-SEDDS) with high photostability and oral bioavailability. The CoQ(10)/s-SEDDS was prepared by spray-drying an emulsion preconcentrate containing CoQ(10), medium-chain triglyceride, sucrose ester of fatty acid, and hydroxypropyl cellulose, and its physicochemical, photochemical, and pharmacokinetic properties were evaluated. The CoQ(10)/s-SEDDS powder with a diameter of ca. 15 µm was obtained by spray-drying, in which the CoQ(10) was mostly amorphized. The CoQ(10)/s-SEDDS exhibited immediate self-emulsification when introduced to aqueous media under gentle agitation, forming uniform fine droplets with a mean diameter of ca. 280 nm. There was marked generation of reactive oxygen species, in particular superoxide, from CoQ(10) exposed to simulated sunlight (250W/m(2)), suggesting potent photoreactivity. Nano-emulsified solution of CoQ(10) under light exposure underwent photodegradation with 22-fold higher degradation kinetics than crystalline CoQ(10), although the CoQ(10)/s-SEDDS was less photoreactive. After the oral administration of CoQ(10)/s-SEDDS (100 mg-CoQ(10)/kg) in rats, enhanced exposure of CoQ(10) was observed with increases in both C(max) and AUC of ca. 5-fold in comparison with those of orally administered crystalline CoQ(10). From the improved physicochemical and pharmacokinetic data, the s-SEDDS approach upon spray-drying might be a suitable dosage option for enhancing nutraceutical and pharmaceutical values of CoQ(10).

Preparation method and stability of ellagic acid-rich pomegranate fruit peel extract.

A simple one-step purification using liquid-liquid extraction for preparing pomegranate peel extract rich in ellagic acid has been demonstrated. The method involved partitioning of the 10% v/v water in methanol extract of pomegranate peel between ethyl acetate and 2% aqueous acetic acid. This method was capable of increasing the ellagic acid content of the extract from 7.06% to 13.63% w/w. Moreover, the antioxidant activity of the extract evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay was also increased (ED(50) from 38.21 to 14.91 micro/mL). Stability evaluations of the ellagic acid-rich pomegranate peel extract in several conditions through a period of four months found that the extracts were stable either kept under light or protected from light. The extracts were also stable under 4 degrees +/- 2 degrees C, 30 degrees +/- 2 degrees C and accelerated conditions at 45 degrees C with 75% relative humidity. However, study on the effect of pH on stability of the extract in the form of solution revealed that the extract was not stable in all tested pH (5.5, 7 and 8). These results indicated that the ellagic acid-rich pomegranate peel extract was stable when it was kept as dried powder, but it was not stable in any aqueous solution.

Assessment of nutrient stability in foods from the space food system after long-duration spaceflight on the ISS.

Maintaining an intact nutrient supply in the food system flown on spacecraft is a critical issue for mission success and crew health. Ground-based evidence indicates that some vitamins may be altered and fatty acids oxidized (and therefore rendered useless, or even dangerous) by long-term storage and by exposure to radiation, both of which will be issues for long-duration exploration missions in space. In this study, the stability of nutrients was investigated in food samples exposed to spaceflight on the Intl. Space Station (ISS). A total of 6 replicates of 5 different space food items, a multivitamin, and a vitamin D supplement were packaged into 4 identical kits and were launched in 2006 on the space shuttle. After 13, 353, 596, and 880 d of spaceflight aboard the ISS, the kits were returned to Earth. Nine replicates of each food item and vitamin, from the same lots as those sent into space, remained in an environmental chamber on Earth to serve as controls at each time point. Vitamins, hexanal, oxygen radical absorbance capacity, and amino acids were measured in identical-lot food samples at each time point. After 596 d of spaceflight, differences in intact vitamin concentrations due to duration of storage were observed for most foodstuffs, but generally, nutrients from flight samples did not degrade any faster than ground controls. This study provided the 1st set of spaceflight data for investigation of nutrient stability in the food system, and the results will help NASA design food systems for both ISS and space exploration missions.

Effect of ionizing radiation on some quality attributes of nutraceutically valued lotus seeds.

Radiation processing has been employed successfully for value addition of food and agricultural products. Preliminary studies were undertaken to evaluate the changes induced by ionizing radiation (up to 30 kGy), in the form of gamma irradiation and electron beam irradiation, on some quality attributes and nutritive values of nutraceutically valued lotus seeds. Significant loss in seed firmness was recorded between control and irradiated seeds, irrespective of radiation source. Similarly, the specific viscosity of irradiated lotus seeds decreased significantly up to a dose of 7.5 kGy. Starch increased after exposure to gamma or electron beam irradiation, whereas the total phenolic contents were decreased. Gamma irradiation revealed an enhancement in protein, while the electron beam showed a decrease. Partial oxidation of the seeds during radiation treatments might have occurred as evidenced from the decomposition profiles (thermogravimetry) during heating. It is evident that ionizing radiation brought about significant and variable changes in the quality and nutritive values of lotus seed. Further exploration of this technology for safety and quality is warranted.