Physicochemical Properties of Mucilage from Domestic Molokhia (Corchorus olitorius)

몰로키아(Corchorus olitorius) 잎에서 추출한 mucilage의 이화학적 특성

  • Published : 2002.10.01

Abstract

Proximate composition, phenolic compounds, and amino acid composition of molokhia (Corchorus olitorius) and molecular weight distribution of its mucilage were determined. Concentrations of dietary fibers and protein were 37.4 and 24.4% of the total dry weight, respectively. Mucilage was obtained by extracting dry molokhia leaves with hot water, followed by the addition of 55% ethanol. Although about 50% of the mucilage was lost during the extration, it was still rich in polyphenol compounds. In mucilage, proteins were composed of glutamic acid, glycine, alanin, and aspartic acid, and molecular weight of most polysaccarides ranged from $40,000{\sim}500,000$ daltons based on gel filtration chromatography.

국내산 몰로키아 잎의 영양성분 및 이로부터 얻은 점질성물질(mucilage)의 이화학적 특성을 조사하였다. 몰로키아 잎은 식이섬유 37.4%, 단백질 24.4%로서 주종을 차지하였고 칼슘의 함량 역시 2,000 mg% 이상으로 대단히 높았으며 비타민 A와 C의 함량은 각각 79 mg%, 39.96 mg%를 차지하였다. 추출온도별 mucilage의 수율은 $50^{\circ}C$에서 가장 높은 8.05%을 나타냈으며 단백질의 총당에 대한 비율이 $50^{\circ}C$의 57.6%에서 $80^{\circ}C$의 38.9%로 점차 낮아지는 경향이 나타냈다. Mucilage의 총 폴리페놀 함량은 몰로키아 잎 보다 낮은 1,800mg%정도이지만 잎의 50% 정도에 달하였다. Mucilage를 구성하는 아미노산의 조성을 분석한 결과 glutamine과 glutamic acid의 함량이 가장 높았고 다음으로 glycine, alanine, aspartic acid의 순 이었다. Sepharose CL-2B column $(3.2{\times}95\;cm)$을 사용하여 mucilage의 다당획분을 조사한 결과 대부분 분자량은 $40,000{\sim}500,000$ dalton정도의 크기를 나타내었으며 50,000 dalton 이하의 것도 일부 존재하는 것으로 나타났다.

Keywords

References

  1. Yoshikawa, M., Shimada, H., Saka, M., Yoshizumi, S., Yamahara, J. and Matsuda, H. Medical foodstuffs. V. Moroheiya. (1): Absolute stereostructures of corchoionosides A, B, and C, histamine release inhibitors from the leaves of vietnamese Corchorus olitorius L. (Tiliaceae). Chem. Pharm. Bull. 45: 464-469 (1997) https://doi.org/10.1248/cpb.45.464
  2. Yoshikawa, M. Moroheiya. Food Sci. (Japan) 41: (1999) https://doi.org/10.1111/j.1365-2621.1976.tb01097.x
  3. El-Mahdy, A.R. and El-Sebaiy, L.A. Preliminary studies on the mucilage extracted from okara fruits, taro tubers, jew's mellow leaves and fenugreek seeds. Food Chem. 14: 237-249 (1984) https://doi.org/10.1016/0308-8146(84)90079-7
  4. Oshodi, A.A. Comparison of protein, minerals and vitamin C contents of some dried leafy vegetables. Pak. J. Sci. Ind. Res. 35: 267-269 (1992)
  5. Farag, R.S., El-Khwas, K.H.A.M. and Mohamed, M.S. Distribution of carotenoids in some fresh and boiled foods. Adv. Food Sci. 20: 1-6 (1998)
  6. Azuma, K., Nakayama, M., Koshioka, M., Ippoushi, K., Yamaguchi, Y., Kohata, K., Yamauchi, Y., Ito, H. and Higashio, H. Phenolic antioxidant from the leaves of Corchorus olitorius L. J. Agric. Food Chem. 47: 3963-3966 (1999) https://doi.org/10.1021/jf990347p
  7. Innami, S., Tabata, K., Shimizu, J., Kusunoki, K., Ishida, H., Matsuguma, M., Wada, M., Sugiyama, N. and Kondo, M. Dried green leaf powders of jew's mellow (Corchorus), Persimmon (Disophyros kaki) and sweet potato (Ipomoea batatas poir) lower hepatic cholesterol concentration and increase fecal bile acid excretion in rats fed a cholesterol-free diet. Pant Foods for Human Nutr. 52: 55-65 (1998) https://doi.org/10.1023/A:1008031028484
  8. AOAC. Official Methods of Analysis. 16th ed. Association of Official Analytical Chemists, Washington, DC, USA (1995)
  9. Nakabayashi, T. Studies on tannin of fruit and vegetables. Nippon Shokuhin Kogyo Gakkaishi. 15: 73-78 (1968) https://doi.org/10.3136/nskkk1962.15.73
  10. Ohtani K., Okai, K., Yamashita, U., Yuasa, I. and Misaki, A. Characterization of an acidic polysaccharide isolated from the leaves of Corchorus olitorius (Moroheiya). Biosci. Biotech. Biochem. 59: 378-381 (1995) https://doi.org/10.1271/bbb.59.378
  11. Laskar, S., Majumdar, S.G. and Basak, B. Extraction and chemical investigation of jute (Corchorus olitorius, Linn.) seed protein. Appl. Biochem. Biotech. 14: 253-257 (1987) https://doi.org/10.1007/BF02800312
  12. Tsukui, M., Nagashima, T., Sato, H., Kozima, T.T. and Tanimura, W. Characterization of yam (Dioscorea opposita Thunb.) mucilage and polysaccharide with different varieties. Nippon Shokuhin Kagaku Kohaku Kaishi. 46: 575-580 (1999) https://doi.org/10.3136/nskkk.46.575