Effect of Thermal Processes on S-Allyl Cysteine Content in Black Garlic.

As a key component of black garlic (BG) products, S-allyl cysteine (SAC) is useful in reducing oxidative stress and inflammation. Several BG products with a high SAC content have been developed by thermal processing; however, the optimum conditions for thermal treatment for producing Thai garlic (multicloves) with a high SAC content compared to Chinese garlic (single clove) are still unknown. Moreover, the mechanism underlying the increase in SAC content in BG is unclear. Thus, this study aimed to investigate the optimum thermal condition for developing Thai BG with high SAC content base on methods A (70 °C and 80% RH) and B (60-75 °C and 80-85% RH). The total phenolic contents and antioxidant activities of Thai fresh garlic, Thai BG, and their powder forms were also compared. Method A worked the best for both types of garlic. The results indicated that the SAC content increased significantly after 7 days of fermentation and decreased drastically afterward with prolonged heat treatment. The optimum thermal condition for producing Thai fresh garlic and Chinese fresh garlic with high SAC content was 70 °C and a relative humidity of 80% for 12 days in an industrial fermentation chamber. The SAC content of Thai BG and Chinese BG increased approximately 139- and 122-fold, respectively. Furthermore, significant antioxidant capabilities determined by ferric ion-reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl radical scavenging, and oxygen radical absorbance capacity assays were 34-, 6-, and 3-fold higher, respectively, than those of fresh garlic.

Anticlastogenic effect of Eryngium foetidum L. assessed by erythrocyte micronucleus assay.

The aim of this study was to investigate the anticlastogenicity as well as the clastogenicity of Eryngium foetidum leaf (EF) using the in vivo mouse peripheral blood erythrocyte micronucleus assay. Eighty ICR male mice were fed AIN-76 diet supplemented with ground freeze-dried EF at 0.0%, 0.8%, 1.6% and 3.2% for 2 weeks prior to the administration of both direct-acting, mitomycin C (MMC), and indirect-acting, 7, 12-dimethylbenz(a) anthracene (DMBA) clastogens. Peripheral blood samples were collected from mice just before administration of clastogen and at 24 and 48 h thereafter for MMC. Blood samples were collected at the same times and after 72 h for DMBA. Then, reticulocytes in blood samples were counted using fluorescent microscopy. The results indicated that EF had no clastogenic effect in mice. All doses of diets supplemented with EF decreased the number of micronucleated peripheral reticulocytes in all the MMC-treated groups in a dose dependent manner, but significant reduction was found only at 1.6% and 3.2% EF in the DMBA-treated groups. It can be concluded that EF has no clastogenicity, but possesses anticlastogenic potential against both direct- and indirect-acting types of clastogen in mice.

Nutritive evaluation and effect of Moringa oleifera pod on clastogenic potential in the mouse.

Moringa oleifera Lam (horseradish tree; tender pod or fruits) has been consumed as a vegetable and utilized as a major ingredient of healthy Thai cuisine. Previous studies have shown that M. oleifera pod extracts act as bifunctional inducers along with displaying antioxidant properties and also inhibiting skin papillomagenesis in mice. This study was aimed to determine the nutritive value, and clastogenic and anticlastogenic potentials of M. oleifera pod. The nutritive value was determined according to AOAC methods. The clastogenic and anticlastogenic potentials were determined using the in vivo erythrocyte micronucleus assay in the mouse. Eighty male mice were fed semi-purified diets containing 1.5%, 3.0% and 6.0% of ground freeze-dried boiled M. oleifera pod (bMO) for 2 weeks prior to administration of both direct-acting (mitomycin C, MMC) and indirect-acting (7, 12-dimethylbenz(a)anthracene, DMBA), clastogens. Blood samples were collected at 0, 24, 48 and 72 h, dropped on acridine orange-coated slides, and then counted for reticulocytes both with and without micronuclei by fluorescence microscopy. The nutritive value of 100 g bMO consisted of: moisture content, 8.2 g; protein, 19.2 g; fat, 3.9 g; carbohydrate (dietary fiber included), 60.5 g; dietary fiber, 37.5 g; ash, 8.1 g and energy, 354 kcal. Freeze-dried boiled M. oleifera had no clastogenic activity in the mouse while it possessed anticlastogenic activity against both direct and indirect-acting clastogens. Freeze-dried boiled M. oleifera pod at 1.5%, 3.0% and 6.0% in the diets decreased the number of micronucleated peripheral reticulocytes (MNRETs) induced by both MMC and DMBA. However, the effect was statistically significant in the dose dependent manner only in the MMC-treated group. In conclusion, the present study demonstrated that bMO has no clastogenicity and possesses anticlastogenic potential against clastogens, and particularly a direct-acting clastogen in the mouse.