• Journal of Food Hygiene and Safety
• /
• v.36 no.4
• /
• pp.347-352
• /
• 2021

Yam (Dioscorea japonica) is widely utilized as food and a pharmaceutical ingredient as it contains a variety of valuable constituents. Allantoin is one of the bioactive components in yam that is used in pharmaceutical and cosmetic industry. This study was conducted to analyze and compare the allantoin content of yam flesh and peel by HPLC analytical method using an amino bonded-phase column to make up for the limitations of the previous HPLC analytical methods. The allantoin contents of yam flesh and peel were 3.09±0.025 and 3.91±0.11 mg/g (dry weight), respectively. The results of this study indicated that yam peel has higher allantoin content than yam flesh, and that the discarded yam peel could be used as a source for high value-added functional materials.

• Plant Resources
• /
• v.1 no.1
• /
• pp.49-52
• /
• 1998

This study confirmed that the initiation time of tuberization was well consistent with the cativation time of JA. The consistency was also cinfirmed in the tuberization of yam plants under the altered condition of natural day length. The final yield of JA from 500g fresh leaves was $89.3{\mu}g$.

• The Korean Journal of Food And Nutrition
• /
• v.5 no.1
• /
• pp.49-54
• /
• 1992

In an attempt of develop composite flours, D. aimadoimo of yams in Korea was investigated with respect to its physicochemical properties and sensory analysis with baking bread. The results are summarized as follows ; 1. Yam had 73.21% of water, 21.65% of carbohydrate, 3.3% of crude protein, 0.25% of fat, 1.60% ash and 20.3%of starch. 2. Sucrose was 78% of the total free sugars in yam flour. It was contained which 67% of total free amino acids were serine, arginine & alanine and 23.6% of total amino acids was glutamic acid. 3. As the yam flour level in amylogram patterns (8% dry basis) was increased, the initial pasting temperature was increased and the viscosity decreased. 4. Replacement of yam flour with 10% wheat flour was the bests in sensory evaluation of the products.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.4
• /
• pp.751-755
• /
• 1998

Functional properties of yam mucilage were investigated by physicochemical analysis. Yam mucilage was extracted from the root of yam and then separated into two fractions by its selective aggregation with isopropanol concentration. Each mucilge fraction showed the excellent binding properties with heavy metal ions Co, Cr and Cu. Cr showed the higher affinity with mucilage than Co and Cu at pH 6.3. In ACE inhibition, IC50 values of mucilage fraction 1 and 2 showed 8.99$\mu\textrm{g}$/${mu}ell$ and 7.1$\mu\textrm{g}$/${mu}ell$, respectively.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.2
• /
• pp.342-351
• /
• 2016

The bioactive compound and antioxidant property of Korean yam (Dioscorea batatas DECNE.) were studied using in vitro methods. Yam available in Korea was analyzed for lycopene, chlorophyll a, b, tannin, phytic acid and total saponin contents. 70% Methanol, 70% ethanol and chloroform-methanol mixture (CM, 2:1, v/v) were used to extract yam. Then the antioxidant activity evaluated through ferrous ion chelating activity, ${\beta}$-carotene bleaching method, lipid peroxidation inhibition and nitric oxide (NO) radical scavenging activity. 70% Methanol extract showed the highest ferrous ion chelating activity and NO radical scavenging activity. And CM extract was the most effective in inhibition of linoleic acid peroxidation evaluated by ${\beta}$-carotene bleaching assay and lipid peroxidation inhibition assay. Based on the results obtained, yam is a potential active ingredient that could be applied in antioxidation as well as bio-health functional food to take a good part in prevention of human diseases and aging.

• Nutrition Research and Practice
• /
• v.1 no.2
• /
• pp.94-99
• /
• 2007

The immunostimulating activities of mucilage fraction from yam were investigated. The proliferation of BSA-primed lymph node cells was enhanced between 4.1- to 10.9-fold compare to control, when cultured with 1 to $25{\mu}g/mL$ of yam-mucilage fraction. It showed strong immunostimulating activity than ginseng extract and as remarkable as Bifidobacterium adolescentis M101-4 known as a positive immunostimulator. Mitogenicity to lymph node cells was fully induced by concanavalin A and lipopolysaccharide. The proliferation of splenocytes and Peyer's patch cells was enhanced between 5.0- to 14.1-fold and 2.4- to 6.4-fold, respectively, when cultured with 1 to $25{\mu}g/mL$ of yam-mucilage fraction. It enhanced the production of cytokines such as tumor necrosis $factor-{\alpha}$ and IL-6 in the culture of RAW 264.7 macrophage cells. In the culture of lipopolysaccharide-stimulated RAW 264.7 cells, production of cytokines was as similar as compared to controls. In unstimulated RAW 264.7 cells, both tumor necrosis $factor-{\alpha}$ and IL-6 production were enhanced between 15.6- to 60.1-fold and 2.3- to 9.1-fold, respectively. Mucilage fraction from yam is expected to be a safe immunopotentiator to maintain the host immunity and develop a physiologically functional food.

• Korean journal of food and cookery science
• /
• v.8 no.1
• /
• pp.57-63
• /
• 1992

The purpose of this study was to investigate the rheological and thermal properties of yam starch. Yam starch had a hydrodynamic volume with the intrinsic viscosity,［$\eta$］, of 0.29dl/g deionized water. The values of the intrinsic viscosity of yam starch, determined to pH 2-11, varied between 0.07 to 0.18 dl/g. The highest intrinsic viscosity was obtained at pH 7. At salt concentrations 0-0.2 M NaCl, the intrinsic viscosity of yam starch was decreased up to 0.05 M NaCl concentration then increased to 0.07 M NaCl concentration and remained constant to reach 0.2 M NaCl concentration. The overlap parameter, calculated with the intrinsic vicosity data, was 3.45 g/dl in deionized water. The thermal properties of yam starch were investigated by Differential Scanning Calorimetry. Three endotherms were observed both pH solution and salt concentation. In the presence of pH 9, the onset temperature of gelatinization peak was the lowest temperature of 50.$32^{\circ}C$ and the enthalpy ($\Delta$H) was increased in this solution. The effect of salt on the thermal properties of yam starch was determined at salt concetration of 0-0.2 M NaCl. The enthalpy significantly decreased to salt concentration 0.07 M NaCl and the lowest onset temperature of this concentration was 52.$90^{\circ}C$.

• Korean journal of food and cookery science
• /
• v.14 no.4
• /
• pp.333-338
• /
• 1998

On the mutagenicity induced by 2-aminofluorene (2-AF) with S9 mix and N-Methyl-N＇-Nitro-N-Nitrosoguanidine (MNNG) without S9 mix, the antimutagenic effects of dietary fiber (total dietary fiber, u-cellulose and pectin) from Yam were examined by the Ames assay using Salmonella typhimurium TA98 and TA100. Total dietary fiber, $\alpha$-cellulose ind pectin from natural and cultural Yam didn＇t have mutagenicity. Most of sample dietary fiber showed the antimutagenicity. Total dietary fiber from cultural Yam was more effective than that from natural Yam on mutagenicity induced by 2-AF and MNNG. $\alpha$-cellulose from cultural Yam was more effective than that from natural Yam on mutagenicity caused by 2-AF and MNNG. Pectin from natural and cultural Yam had antimutagenic effect on mutagenicity induced by MNNG. In this study, antimutagenicity on MNNG was more effective than that on 2-AF. Antimutagenic effect of Samples had influence on incubation time. $\alpha$-cellulose and pectin from natural and cultural Yam showed stronger antimutagenic effect than standard $\alpha$-cellulose and standard pectin, respectively, on mutagenicity induced by 2-AF and MNNG.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.1
• /
• pp.8-14
• /
• 2011

The effect of flooding and soil salinity on the growth of yam (Dioscorea batatas) were studied on the experimantal site temporally established in the south-eastern part of Saemangeum Reclaimed Tidal Land (near Gwanghwal myun, Gimjae-gun, Jellabukdo, Korea). Yam seedlings planted by using aerial bulblet as alternative of sliced tubers, were grown for 20-days and transplanted in black-vinyl mulched ridges (about 20 cm in height) at 70cm interval by $20{\times}60cm$ spacing in the $4^{th}$ of May, 2010. Soil salinity was maintained at lower than 1.2 ds $m^{-1}$ during the growing period and did not result to salt injury in all plants. However, flooding injury very seriously led to plant death and plant mortality rates at $67{\pm}21$ and $82{\pm}9%$ of yam plants in the compost and no compost treatment, respectively, died by heavy flooding during the rainy summer season. The main reasons of the flooding injury included the decreased rainfall acceptable capacity (RAC) after the rising of water table and a slowdown of water infiltration rate after the formation of an impermeable soil crust in the furrow bottom with continuous and heavy downpour during the rainy summer season. The effect of compost treatment was not statistically observed because of the severe spatial difference caused by wet injury, although yam tuber yield was higher at 30 kg $10^{-1}$ in the compost treatment than in the no-compost treatment at 20 kg $10^{-1}$. However, the size of tuber ranged at 1.23 to 1.60 cm in diameter and 3.7 to 5.0 cm in length in all both treatment, which means they are still reproducible for the next cropping season. Conclusively, proper counter-flooding measure and soil salinity control critically important for successful yam production in Saemangeum Reclaimed Tidal Land.

• Journal of the Korean Applied Science and Technology
• /
• v.32 no.1
• /
• pp.7-15
• /
• 2015

In this study, the thermal treatment yam (Dioscorea batatas DECNE.) was analyzed for its proximate and nutritional compositions including mineral, vitamin, amino acids and fatty acids. Thermal treatment yam is mainly consisted of carbohydrate (70.3%) with small amounts of crude protein (15.8%), crude ash (5.1%) and crude fat (1.6%). It was found to be a good source of essential minerals such as K (1100.2 mg/100 g), Mg (99.4 mg/100 g), Ca (54.8 mg/100 g) and Na (44.9 mg/100 g) but Zn (4.8 mg/100 g) and Fe (0.2 mg/100g) content was low. Little amounts of vitamin E (8.3 mg/100g), vitamin C (3.5 mg/100g) and vitamin B1 (2.1 mg/100g) could be found. The amino acid analysis revealed that the yam was superior with respect to serine (1454.2 mg%), lysine (684.6 mg%) and histidine (684.6 mg%). Essential amino acids were calculated to be 2849.3 mg%. The amino acid profiles showed that thermal treatment yam is limiting in isoleucine and phenylaline. Linoleic acid was the most predominant fatty acids with the value of 47.3% followed by palmitic acid (24.7%) and oleic acid (12.7%). And the unsaturated fatty acids including oleic acid and linoleic acid were present in big quantities in thermal treatment yam.