• Korean Journal of Food Science and Technology
• /
• v.32 no.2
• /
• pp.291-297
• /
• 2000

Oleoresin was extracted from fresh garlic by microwave-assisted extraction (MAE) and its functionality and antibrowning effect were investigated at various extraction conditions. The yield and polyphenol contents of the garlic oleoresin were inversely related to extraction time. The highest yield was l2.9% and maximum polyphenol contents was 574.3 mg% when the oleoresin was extracted for 5 min with ethanol. Apparently, the electron donating abilities of garlic oleoresin increased with extraction time, but there were no significant differences among extraction time intervals. The highest nitrite scavenging effect was found at pH 1.2 and decreased as pH increased. Tyrosinase inhibitory effect was less than 30% for most garlic oleoresin but the 15 minute extraction with ethanol resulted in higher inhibitory effect. Angiotensin I-converting enzyme (ACE) inhibitory effect was highest (89.2%) when oleoresin extracted with ethanol for 20 min. The addition of cysteine, ascorbic acid and citric acid to oleoresin extracts retarded browning action of garlic oleoresin during 10 day storage. 0.1 % cysteine retarded browning reaction and some synergistic effect was found in the combination of citric acid and ascorbic acid.

• Journal of Applied Biological Chemistry
• /
• v.59 no.3
• /
• pp.243-245
• /
• 2016

The insecticidal toxicities of seven essential oils against Ricania sp. nymph and adults, newly recorded pest, were evaluated using leaf-dipping and spray methods. At 72 h exposure time, the $LC_{50}$ values of the essential oils of Artemisia vulgaris, Anethum graveolens, Citrus paradisi, Melaleuca alternifolia, Melaleuca leucadendron, Neroli bigarade and Tagetes erecta were 251.02, 387.31, 286.21, 353.54, 275.64, 424.55, $165.68mg/cm^2$ when using the leaf dipping method against Ricania sp. nymphs, and 278.31, 402.11, 306.11, 379.64, 298.22, 459.56, $183.21mg/cm^2$ when using the spray method against Ricania sp. adults, respectively. These results indicate that the essential oil of the Tagetes erecta can be potentially used as new natural insecticidal agents against Ricania sp. nymph and adults.

• Applied Biological Chemistry
• /
• v.24 no.3
• /
• pp.161-166
• /
• 1981

Products of ginseng browning reaction were investigated to determine the nature of their antioxidant activity using a model system, White Ginseng and Red Ginseng extracts. In the simulated ginseng model system, the brown color was intensified with an increase in the length of reaction time and the antioxidant activity initially increased in proportion the length of reaction time for up to 17 hrs and then leveled off thereafter. Pararell results were obtained manufacturing of Red Ginseng, Comparison of the antioxidant activity of the inner and outer solutions after dialysis of browning solution showed that the outer solution had a stronger antioxidant activity than the inner one. For further analyses, browning reaction products were fractionated into three peaks on Amberlite CG-120 type I ionexchange resin and designated as fractions I, II and III in order of elution. Partial characterization of the fractions revealed that floe most intense brown fraction (Fraction II) had the strongest antioxidant activity and also exhibited reducing power for Somogyi-Nelson reagents and ninhydrin positive reaction. Both the browning reaction products and Red Ginseng extracts were found to possess potent reactivity with ${\alpha}$,${\alpha}'$-diphenyl-${\beta}$-picrylhydrazyl, whereas White Ginseng extracts showed negligible reactivity.

• Journal of Life Science
• /
• v.29 no.8
• /
• pp.922-940
• /
• 2019

Obesity, represented by abnormal fat accumulation due to an imbalance between energy intake and expenditure, is a major public health issue worldwide, leading to multiple noncommunicable diseases, including atherosclerosis, hypertension, type 2 diabetes, and cancer. Diverse solutions have been proposed to combat obesity. Attention has focused on two types of adipose tissues as a promising therapeutic target in obesity: traditional brown and beige or brite. Unlike energy-storing white adipose (endocrine) tissue, traditional brown adipose tissue and beige adipose tissue have energy-dissipating thermogenic properties. Both types of tissue are present in adult humans and inducible through external stimuli, such as cold exposure, ${\beta}3$-adrenergic receptor agonists, and phytochemicals. Among these stimuli, microbiota present in the human intestinal tract participate in multiple metabolic activities. Modulation of gut microbiota may offer a potent and possibly curative strategy against various metabolic diseases. Numerous studies have focused on the effects of established antiobesity treatments on the gut microenvironment or brown-adipose-tissue activation. In this review, we focus mainly on stimuli known to alleviate obesity, weight gain, and metabolic diseases, in addition to known and possible inter-relations between gut microbiota modulation and similar interventions and adipose tissue browning. The findings may pave the way toward new strategies against obesity.

• Proceedings of the Korean Society of Food and Cookery Science Conference
• /
• 1985.12a
• /
• pp.139.2-140
• /
• 1985

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.6
• /
• pp.152-158
• /
• 2007

Micromorphological and chemical characteristics of living Castanea spp. and Tamarix spp. attacked by a brown-rot fungus were examined. Micromorphological features of brown-rotted hardwood species were similar to those observed in softwoods such as losses in birefringence under polarized microscopy, preferential degradation of $S_2$ layer and cracks in the $S_3$ layer. Thinning of the secondary cell wall in fibers was also observed, although it did not seem to be the main symptom. FT-IR analysis showed that bands assigned to cellulose and hemicelluloses decreased or disappeared, whereas the bands assigned to lignin increased. X-ray diffraction analysis exhibited the decrease of relative crystallinity, indicating that degradation of hardwood by a brown-rot fungus was in the advanced stages.

• Journal of the East Asian Society of Dietary Life
• /
• v.14 no.1
• /
• pp.70-73
• /
• 2004

The browning rate of potato juice alone and potato juice with added carrot juice or water(1:1 by volume) were studied. As the amount of carrot juice added was increased, the browning rate proportionally decreased: from 1.86 of potato juice alone to 0.36 for the potato juice and carrot juice mixture(l:1). This inhibitory effect of carrot juice on browning led us to assume that $\beta$-carotene, the major constituent of carrot carotenoids, may be involved in impeding the browning reaction of potato juice. Therefore, model system of enzymatic browning, consisting of chi orogenic acid/tyrosine and $\beta$-carotene/carrot carotenoids, were studied. The results shows the browning rates of chlorogenic acid alone and chlorogenic acid with added $\beta$-carotene. The initial browning rate of chlorogenic acid was faster($\delta$L= 1.1/min.)than that of chlorogenic acid with added $\beta$-carotene($\delta$L=0.6/min.).

• Korean Journal of Food Science and Technology
• /
• v.34 no.5
• /
• pp.751-756
• /
• 2002

For the development of functional jang-products, kanjang was prepared using barley bran. Optical density of barley bran kanjang was significantly high at 15 days after fermentation, and the amount of extract was $2{\sim}3$ fold higher than that of soybean kanjang. Among the flavor components identified in barley bran kanjang, the content of 2-furancarboxaldehyde was the highest, followed by 4-vinyl-2-methoxy-phenol, benzene-acetaldehyde, palmitic acid, and methyl-9,12-octadecadienoate. In barley bran and soybean mixtare (1 : 1) kanjang, the content of 2-furancarboxaldehyde was the highest, followed by benzeneacetaldehyde, diethyl phtalate, palmitic acid, and 2-chloroethyl linoleate. Flavor components detected in both barley bran kanjang and barey bran and soybean mixture kanjang were 2-furancarboxaldehyde, benzaldehyde, benzeneacetaldthyde, 4-vinyl-2-mehtoxy-phenol, 1-furfuryl-2-formy pyrrole, dimethyl-1,2-benzenedicarboxylate, diethyl phtalate, palmiticacid, dibutyl-1,2-benzenedicarboxylate, and di-(2-ethylhexyl)phthalate.

• Korean Journal of Food Science and Technology
• /
• v.10 no.3
• /
• pp.350-355
• /
• 1978

An attempt was made to compare the antioxidant activity of ethanol extracts of a glucose-ammonia (0.2 M+0.2 M) browning mixture with that of the corresponding glucose-glycine mixture, in soybean oil substrates, on the basis of peroxide value (POV), thiobarbituric acid value (TBA-value) and acid value (AV) development. Absorbances, at 470 nm, of the former mixture after 2 and 5 hour browning were 1.88 and 3.42 while those of the latter mixture were 0.02 and 0.07. The POVs of the supstrates containing the extracts taken after 2, 15, and 40 hrs from the former mixture were 15.8, 14.2, and 12.6 after 30 day storage at $42.3{\pm}2.6^{\circ}C$. Those of the latter mixture were 17.4, 16.1, and that of the control was 82.1. TBA and acid value developnent followed similar trends. These results indicated that the antioxidant activity of the extracts of the glucose-ammonia mixture was slightly stronger than that of the glucose-glycine mixture. They also suggested that effective antioxidants had already been formed in the earlier stages of the glucose-anmonia mixture, and that brown-pigments formed did not contribute significantly to the activity of the mixture.

• Proceedings of the Ginseng society Conference
• /
• 1988.08a
• /
• pp.99-107
• /
• 1988

Samples of red ginseng. which had been manufactured and packaged by the Korea Monopoly Corporation. were stored at ambient temperatures $(12-28^{\circ}C)$ and humidities $(55-68\%)$ for one to nine years to examine their overall quality stability and. in particular. antioxidant activity. The approximate compositions. contents of various solvent extracts. and TLC and HPLC patterns of ginsenosides in the samples which are otherwise susceptible to oxidation. were stable as judged by the changes of the TLC and GLC patterns of the lipids and fatty acids. It was also found that polyunsaturated fatty acids such as linoleic (C18: 2) and linolenic acid (C18: 3) present in the samples had been very stable during the long storage periods. The intensity of the brown color of the red ginseng samples increased significantly with storage time. The pH of the aqueous extracts of the samples also increased slightly during storage. The coloration changes seem to indicate that extensive browning reactions had occurred during storage. The reducing powers of aqueous and ethanol extracts and antioxidant activity of ethyl acetate extracts also increased with storage time. The increase in reducing powers and antioxidant activity appeared to be directly attributable to the increased amounts of non-enzymatic browning reaction products formed progressively during the long storage periods. Therefore. it seems that those antioxidative compounds. which will be progressively formed in red ginseng through non-enzymatic browning reactions during the manufacturing process and long-term storage. will not only contribute to their overall quality stability but also have some significant relationship with their antiaging pharmacological effects.