• Korean Journal of Pharmacognosy
• /
• v.15 no.1
• /
• pp.30-38
• /
• 1984

Yam, Dioscorea batatas Decne (Dioscoreaceae) is a plant growing in Korea. Dioscoreae Rhizoma in the markets are classified into natural and cultural ones. These studies were conducted to investigate the differencies between natural and cultural Yams by characteristics of morphology, cell contents, chemical components and physical properties. More mucilage cells which contain calcium-oxalate raphides were contained in cultural Yam than natural Yam. However, the amount of crude protein, crude lipid and mucilage viscosity, swelling, gelatinization of polysaccharides were greater in natural Yam than the other. It is suggested that natural Yam is excellent as nutrition agent in quality and worthwhile as a resource of crude drugs.

• Korean Journal of Medicinal Crop Science
• /
• v.6 no.1
• /
• pp.33-37
• /
• 1998

Browning index rised rapidly within 15 hrs to 83% of total browning in Jang - ma (Dioscorea batatas Decne) tissues at $40^{\circ}C$ while 37% in Dan - ma. Therefore, the degree of browning process of Jang - ma was faster than that of Dan - ma. Browning in Jang - ma was inhibited by treatments of NaCl which showed 48 and 39% inhibition, respectively, after 48 hrs of incubation. Also the treatment of $80^{\circ}C$ heating showed excellent inhibition within 24 hrs. In the case of Dan - ma, browning process was inhibited by treatments of 1 and 0.5M NaCl and $70^{\circ}C$ heating, which showed 43, 26 and 23% inhibition, respectively, after 48 hrs of incubation.

• Microbiology and Biotechnology Letters
• /
• v.37 no.3
• /
• pp.266-272
• /
• 2009

The annual productions of yam and its aerial bulbils are estimated to 5,000 and 2,500 ton, respectively. But the majority of bulbils had been discarded without specific use. In this study, methanol extract and its organic solvent fractions were prepared from bulbils of Dioscorea batatas Decne, and their antimicrobial, antithrombin, and antioxidant activities were evaluated, respectively. The methanol extract contained 58.98% of water-soluble materials as like yam's extract. But the bulbils's extract contained 12-folds of total polyphenol and 3.4-folds of total flavonoids compared than yam's extract, respectively. For antimicrobial activity the hexane and ethyl acetate fraction showed strong antibacterial activity at $500{\mu}g/disc$ concentration against gram-negative and gram-positive bacteria. Antifungal activity was not observed in any fractions. Strong antithrombin activity was found in the hexane fractions. At 4.8 mg/mL concentration thrombin time (TT) was over 300 sec, which is 4-folds extended than the TT of yam. In a while, the ethyl acetate fraction showed strong DPPH scavenging activity ($IC_{50}$ of $38.1{\mu}g/mL$), SOD-like activity and reducing power, which are comparable to vitamin C or BHT. Our results suggest that the bulbils of yam as yam tuber have useful bio-activities, such as antibacterial, antithrombosis, and antioxidant activity.

• 한국약용작물학회:학술대회논문집
• /
• 2007.05a
• /
• pp.181-182
• /
• 2007

• 한국약용작물학회:학술대회논문집
• /
• 2011.04a
• /
• pp.152-153
• /
• 2011

• 한국약용작물학회:학술대회논문집
• /
• 2010.10a
• /
• pp.199-200
• /
• 2010

• BMB Reports
• /
• v.40 no.6
• /
• pp.1016-1020
• /
• 2007

In this study, dioscin was isolated from Dioscoreae Rhizoma (DR), which is the rhizome of Dioscorea batatas DECNE. that inhabits broad areas of Korea and Japan. To determine whether dioscin induced growth hormone (GH) release, we evaluated its induction effects on GH release both in vitro and in vivo. The 70% methanol extract of DR, and its n-hexane and n-BuOH fractions, induced rat GH (rGH) release in rat pituitary cells 10-fold, 8-fold, and 5-fold higher than the control ($0.36{\pm}0.02 nM$), respectively (p < 0.05 each). The dioscin-induced rGH release of the cells was concentration-dependent and its $ED_{50}$ was $1.14{\times}10^{-5} M$. Within 90 minutes after intravenous administration of $10{\mu}g$/kg (p < 0.05 at $t_{max}$), dioscin caused the greatest increase in rGH concentration ($C_{max}$) in the rat plasma ($34.16{\pm}14.10 ng/ml$) (n = 4), which was twice as high as the control group ($12.88{\pm}3.29 ng/ml$) (n = 27).

• Korean Journal of Medicinal Crop Science
• /
• v.6 no.3
• /
• pp.170-175
• /
• 1998

This study was conducted to determine the effect of seminal sections of tuber and staking methods on growth and yield of a chinese yam (Dioscorea batatas Decne). Tuber was divided into top head, head, median and tail which were used as seminal sections of tuber. The emergence of shoots was delayed in median and tail sections by 15 days as compared with top head and head sections. Sections from head and tail exhibited yield increase as high as 16 and 15%, respectively, compared to top head sections. Although flowering and bubil setting occurred almost at the same time in all staking methods, fresh weight of stem and leaves was higher in ${\wedge}-$, I-type stake supporting net than in the conventional stake. In the cultivar, 'Dan-ma', tuber yield didn't show a meaningful increase statistically by all staking methods. But ${\wedge}-$ and I-type stake supporting net increased the yield of the cultivar, 'Jang-ma', as high as 11 and 8%, respectively, compared to conventional stake. Also I-type stake was ideal supportor of net, considering the cost of management.

• Korean Journal of Medicinal Crop Science
• /
• v.22 no.2
• /
• pp.91-97
• /
• 2014

The contents of index components in 5 medicinal crops cultivated at different heights in Andong area. The contents of allantoin in Dioscorea batatas Decne and catalpol in Rehmannia glutinosa Liboschitz were not different by cultivation heights (100 ~ 200m). But the contents of index components in Astragalus membranaceus and Angelica acutiloba Kitagawa were higher in samples cultivated at elevated heights. At 700 m of heights, the contents of formononetin and astragaloside I in Astragalus membranaceus were 1.20 and $201.2{\mu}g/g$, respectively. The contents of decursin and nodakenin in Angelica acutiloba Kitagawa were 68.3 and 4.20 mg/g, respectively. Thus Astragalus membranaceus and Angelica acutiloba Kitagawa are recommended to be cultivated in higher altitude.

• Korean Journal of Medicinal Crop Science
• /
• v.4 no.1
• /
• pp.52-57
• /
• 1996

This study was carried out to compare isozyme band pattern, growth characteristics and tuber yield of Dioscorea batatas to get basic information for varietal classification. It could be identify clearly by protein and esterase band pattern of leaf, petiole and stem tissue in three cultivar but with peroxidase band it was difficult to identify because of similar pattern in leaf and petiole tissue. Three cultivars has different leaf shape as Dan-ma and Jang-ma were lanceolate, Sukunea was long-heart shape in upper part of plants. In phyllotaxis, Dan-ma and Jang-ma shows alternate and opposite but Suwon 2 shows opposite in upper parts of stem. Root length shows significant difference from 9.7cm to 51cm respectively as 30cm, 51cm and 9.7cm in Dan-ma, Jang-ma and Sukunea. Tuber yield of three cultivars were 27.5M/T in Dan-ma, 22.8M/T in Jang-ma and 22.8M/T/ha in Sukunea.