REGULAR PAPERS
Effect of Depigmentation for 3,4-di-O-Caffeoylquinic Acid Guided by
Tyrosinase Inhibitory Activity from Conyza filaginoides,
T. TADA1,
Y. TEZUKA2, K. SHIMOMURA1, S. ITO1, H. HATTORI1
and S. KADOTA2,
1: Research & Development Department, Mikimoto Pharmaceutical Co., Ltd., 1425 Kurose-cho, Ise 516-8581, JAPAN and 2: Research Institute for Wakan-Yaku (Traditional Sino-Japanese Medicines), Toyama Medical
and Pharmaceutical University, 2630-Sugitani, Toyama 930-0194, JAPAN.
Examination of a water extract of Conyza filaginoides guided by
tyrosinase inhibitory activity afforded twelve compounds including five
phenylpropanoids, three flavonoids, two nucleic acids and two icarisides. Among
them, four compounds, 3,4-di-O-caffeoylquinic acid 3, 4-O-caffeoylquinic acid 4, chlorogenic acid 5 and rutin 8 showed strong inhibitory activities with IC50s of 57.7, 393.7, 273.2 and 113.7mM, respectively, and their inhibition modes were noncompetitive. The whitening effect of the most effective compound 3 was also examined, and it showed distinct depigmentation against UVB-irradiated skin of brown guinea pig (the depigmentation percentage was 30.8%).
J. Oleo Sci. 50, 211-215 (2001).
Chemical Composition of Soybean Oil Extracted from Hypocotyle-Enriched Soybean Raw Material and Its Cholesterol Lowering Effects in Rats,
Y. OZAWA1,
H. SATO1, A. NAKATANI2, O. MORI1, Y. HARA1,
Y. NAKADA2, Y. AKIYAMA3 and Y. MORINAGA1,
1:
Food Research & Development Laboratories, Ajinomoto Co., Inc., 1-1, Suzuki-cho,
Kawasaki-ku, Kawasaki-shi, Kanagawa 210-8681, JAPAN, 2: Production &
Technical Department, Ajinomoto Oil Mills Co., Inc., 7-41, Daikoku-cho, Tsurumi-ku, Yokohama-shi, Kanagawa 230-0053, JAPAN and 3: Clinical Development, Pharmaceutical Division, Ajinomoto Co., Inc., 15-1, Kyobashi 1-chome, Chuo-ku,
Tokyo 104-8315, JAPAN.
Soybean oil (termed Soybean-germ oil to distinguish it from normal soybean oil)
was extracted from hypocotyle-enriched (37%) soybean raw material and its
chemical composition was analyzed. The total sterol content in Soybean-germ oil
was 1.7%, which is higher than that in soybean oil (0.4%), corn oil (1.1%) and
rice bran oil (1.0%). The ratio of Campesterol to the total sterols of
Soybean-germ oil was 8.1% that was lower than those of soybean oil (20.2%),
corn oil (20.5%) and rice bran oil (15.7%), respectively. The sum of D 7-Stigmastenol, D 7-Avenasterol and Citrostadienol in Soybean-germ oil was 517mg/100g, which was higher than in corn oil (30mg) and rice bran oil (230mg), respectively. Its cholesterol
lowering effects in rats were evaluated. Between the rats fed test feeds
containing 0.5% cholesterol and 10% test oils, the increases in the serum and
liver cholesterol levels were more suppressed in the rats fed Soybean-germ oil
than in those fed soybean oil. The higher sterol content in Soybean-germ oil
may be related to its enhanced cholesterol lowering effects.
J. Oleo Sci. 50, 217-223 (2001).
Inhibition of the Activity of Mouse Macrophage Scavenger Receptors by
Antioxidants,
M. BEPPU, T. WATANABE, M. KASAHARA, M. WATANABE and K.
KIKUGAWA,
School of Pharmacy, Tokyo University of Pharmacy and Life Science,
1432-1 Horinouchi, Hachioji, Tokyo 192-0392, JAPAN.
Effect of exogenously added antioxidants on the activity of the mouse macrophage
scavenger receptors for oxidized low density lipoprotein (oxLDL) was investigated. Binding of oxLDL-coated erythrocytes and/or 125I-oxLDL to a monolayer of thioglycollate-induced peritoneal macrophages preincubated with antioxidants at 37°C for 2h was examined. The binding was effectively or slightly decreased by preincubation of macrophages with probucol, butylated hydroxytoluene, a-tocopherol, sesamol, propyl gallate, quercetin, nordihydroguaiaretic acid, epicatechin gallate, epigallocatechin gallate
(EGCg), glutathione isopropyl ester (GSH-Pr), N-acetylcysteine, ascorbic acid,
erythorbic acid, and Desferal at concentrations lower than 100mM. The binding was slightly enhanced by preincubation of macrophages with buthionine
sulfoximine. The antioxidants and related compounds inhibited the formation of
foam cells induced by oxLDL in the prolonged incubation for 24h. Glutathione,
oxidized glutathione and dehydroascorbic acid inhibited the foam cell
formation. Total cholesterol accumulation induced by oxLDL in the prolonged
incubation was reduced by the phenolic antioxidants. The number of scavenger
receptors of macrophages was unchanged upon treatment with EGCg and GSH-Pr. The
results indicate that the antioxidants at relatively high concentrations inhibited
macrophage functions, binding of oxLDL, foam cell formation, and accumulation
of cholesterol, and suggest that the scavenger receptor activity of macrophages
was exerted by certain oxidative mechanisms.
J. Oleo Sci. 50, 225-235 (2001).
Improved Method for Preparation of the Methyl Ester of Conjugated Linoleic
Acid,
T. KAMEGAI1, M. KASAI1 and I. IKEDA2,
1: Department of Research and Development, Rinoru Oil Mills Co., Ltd., 13-12
Nihonbashi 2-chome, Chuo-ku, Tokyo 103-0027, JAPAN and 2: Laboratory of Nutrition
Chemistry, Department of Bioscience and Biotechnology Faculty of Agriculture,
Graduate School Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka-shi,
Fukuoka 812-8581, JAPAN.
The authors established a simple method for conducting the quantitative
analysis of conjugated linoleic acid using BF3-methanol solution as
methylation reagent. Following the addition of 25 mg of conjugated linoleic
acid to 2mL 14% BF3-methanol solution and heating for 10 min at
40°C, there appeared to be no significant isomerization of CLA to t,t-isomers
or production of methoxy artifacts. Triglyceride containing CLA (25mg), was
saponified with 1.5mL 0.5M NaOH-methanol solution for 7min at 100°C and to
which 2mL 14% BF3-methanol solution were added followed by heating
for 10min at 40°C. CLA recovery, measured using heptadecanoic acid as internal
standard, was 99.7±0.3% (n=3) and 99.7±0.4% (n=3), when analyzed in free fatty
acid and triglyceride forms, respectively. The present improved method for
preparing the methyl ester of conjugated linoleic acid would thus appear useful
for the quantitation of CLA in foods.
J. Oleo Sci. 50, 237-241 (2001).
Effects of Emulsifiers on Fat Bloom Stability of Cocoa Butter,
T.
KATSURAGI1 and K. SATO2,
1: Yokohama Research Center,
Mitsubishi Chemical Corporation, 1000 Kamoshida-cho, Aoba-ku, Yokohama-shi
227-8502, JAPAN and 2: Faculty of Applied Biological Science, Hiroshima
University, 1-4-4 Kagamiyama, Higashi-Hiroshima-shi 739-8529, JAPAN.
Fat boom stability of cocoa butter to which sucrose fatty acid ester, POS-135,
and polyglycerol fatty acid esters, 10G9POS and 10G12POS had been added was
studied by scanning electron microscopy (SEM) and X-ray diffraction measurement
(XRD) so as to clarify the mechanism for anti-bloom effects of emulsifiers.
Fatty acids compositions of the emulsifiers were similar to that of cocoa
butter, all involving palmitic, stearic and oleic acids. Cocoa butter was
crystallized in form V by seeding b2 form
crystals of 1,3-behenoyl-2-oleoyl glycerin and transformation to form VI was
examined by tempering for 432 hours through 20°C (12 hours) and 30°C (12 hours)
thermocycle.
In the case of cocoa butter without emulsifiers, XRD showed cocoa butter to be
completely transformed from form V to VI after a 120 hour thermocycle treatment
before fat bloom could be visually observed. Bloom was observed after a
292 hour thermocycle.
It was observed that POS-135 retarded the transformation of cocoa butter and
fat bloom formation most enhancedly in comparison with 10G9POS and 10G12POS.
This means that the effect of hydrophilic unit structure of sucrose of POS-135
is important for the inhibition the fat bloom formation.
J. Oleo Sci. 50, 243-248 (2001).
Determination of Sucrose Fatty Acid Esters by High-performance Liquid
Chromatography,
H. OKUMURA, N. KITAZAWA and S. WADA,
Research &
Development Center, Dai-ichi Kogyo Seiyaku Co., Ltd., 55 Nishi-shichijo
Higashikubo-cho, Shimogyo-ku, Kyoto-shi 600-8873, JAPAN.
The procedure for the quantitative analysis of the ester composition of the
sucrose fatty acid esters (SE) is described. SE were separated into their
esters from monoester to octaester by the reversed-phase high-performance
liquid chromatography (RP-HPLC) with a ternary stepwise gradient of water, methanol
and tetrahydrofuran. These esters were detected by an evaporative light
scattering detector (ELSD). ELSD is suitable for gradient elution because it is
completely insensitive towards volatile components, such as the solvents
typically used in HPLC. Each ester was cut from the HPLC column, treated with
alkali, and determined colorimetrically by using anthrone reaction. The
measured value was evaluated by comparison with that of another method using
refractive index detection.
This procedure investigated can provide the baseline separation into their
esters in HPLC and the simultaneous determination of all esters on a single
run. Furthermore, this procedure is more convenient than other methods since it
uses sucrose as a standard for quantification.
J. Oleo Sci. 50, 249-254 (2001).
NOTES
Low Inhibitory Activities of Food Phenolics Against Binding of Estradiol to
Human Estrogen Receptor a,
H. MI, K. HIRAMOTO and K. KIKUGAWA,
School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1
Horinouchi, Hachioji, Tokyo 192-0392, JAPAN.
Inhibitory effects of food phenolics including synthetic antioxidants,
genistein, catechins and quercetin on the binding of radiolabeled estradiol to
human estrogen receptor a were examined, and were compared with that of phenolic
bisphenol A. While inhibitory activity of bisphenol A was 1/100 fold that of
the control cold estradiol, inhibitory activities of the food phenolics were
less than 1/3000 that of the control cold estradiol. The results do not suggest
endocrine discupting properties of food phenolics including synthetic
antioxidants, catechins and flavonoids.
J. Oleo Sci. 50, 255-257 (2001).
Features of 4-Desmethylsterols in Tomato Shoots,
S. TAKATSUTO and Y.
NARUMI,
Department of Chemistry, Joetsu University of Education, 1 Yamayashiki-machi, Joetsu-shi, Niigata 943-8512, JAPAN.
Shoots of tomato (Lycopersicon esculentum) were examined for the presence of
4-desmethylsterols. All shoots of chika (mini-tomato) and momotarou (normal
type) were found by GC-MS to contain three D 7-sterols (lathosterol, 24-ethyllathosterol, and avenasterol), nine D 5-sterols (cholesterol, 24-methylenecholesterol, campesterol,
24-methyldesmosterol, stigmasterol, 24-ethylcholesta-5, 25-dien-3b-ol, sitosterol,
isofucosterol, and 24-ethyldesmosterol), and four C-5 saturated sterols
(cholestanol, campestanol, D 22-stigmastenol, and sitostanol). Each
shoot was found to have very similar sterol profile: cholesterol, stigmasterol,
sitosterol and isofucosterol were major sterol components in these shoots.
J. Oleo Sci. 50, 259-261 (2001).