• Food Science and Preservation
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• v.16 no.6
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• pp.884-892
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• 2009

We determined the chemical changes occurring in oil after exposure to high temperatures for various periods of time. Alterations in the chemical parameters of oil after heating for 30, 60, 90, and 120 min at 120C were investigated. The study involved cold-pressed perilla oil (CPPO), virgin perilla oil (VPO), and commercial heat press-extracted perilla oil (CHPEPO), and we assessed quality properties such as Hunter's color values, browning color intensity, acid value, conjugated dienoic acid level, peroxide value, total phenolic content, electron-donating ability, and fatty acid concentration. Hunter L values were higher for CPPO than for VPO or CHPEPO, whereas browning color intensity was greatest for CHPEPO. Peroxide value data showed higher levels of oxidation products in CPPO than in VPO or CHPEPO, whereas conjugated dienoic acid level was most increased in CHPEPO. The content of total phenolics and electron-donating ability were higher in CHPEPO than in CPPO or VPO. After thermal treatment, fatty acid content was most altered in CPPO; in particular, the level of polyunsaturated fatty acids dropped significantly. Hunter L value, acid value, conjugated dienoic acid level, and peroxide concentration also increased whereas Hunter a and b values, browning color intensity, and total phenolic content were decreased in perilla seed oils after thermal oxidation treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1572-1578
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• 2005

Response surface methodology was used for monitoring changes in physicochemical properties with heating condition of ginseng which was sliced and freeze-dried. As heating temperature and time increased, soluble solid content decreased and browning color increased. Also, acidic polysaccharide and total phenolics increased with the increase in heating temperature and time. Heating condition for maximum soluble solid content was 146.05$^{\circ}C$ in heating temperature and 18.16 min in heating time. Maximum value of crude saponin content was 64.40 mg/g in 160.00$^{\circ}C$ and 20.00 min. Crude saponin content was influenced by heating time but the other properties were influenced by heating temperature.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2001.12a
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• pp.95-109
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• 2001

The traditional (European) Mediterranean diet is characterized by an abundance of plant foods such as bread, pasta, vegetables, salad, legumes, fruit, nuts; olive oil as the principal source of fat; low to moderate amounts offish, poultry, dairy products and eggs; only small amounts of red meat; low to moderate amounts of wine, normally consumed with meals. This diet is low in saturated fatty acids, rich in carbohydrate and fibre, and has a high content of monounsaturated fatty acids (MUFA). These are primarily derived from olive oil. Despite a wealth of general knowledge concerning the major classes of compounds present in olives and olive oil, detailed knowledge of the phenolic antioxidant content has been lacking. Therefore the aim of the study was to evaluate the phenolic antioxidant content in a range of olive and seed oils. While seed oils were devoid, on average, the olive oils contained $196{\pm}19mg/kg$ total phenolics as judged by HPLC analysis, but the value for extravirgin ($232{\pm}15 mg/kg$) was significantly higher than that of refined virgin olive oil ($62{\pm}12mg/kg$; P<0.0001). Appreciable quantities of simple phenols (hydroxytyrosol and tyrosol) were detected in olive oils, with significant differences between extravirgin ($41.87{\pm}6.17$) and refined virgin olive oils ($4.72{\pm}2.15$; P<0.01). The major linked phenols were secoiridoids and lignans. Although extravirgin contained higher concentrations of secoiridoids ($27.72{\pm}6.84$) than refined olive oils ($9.30{\pm}3.81$) this difference was not significant. On the other hand the concentration of lignans was significantly higher (P<0.001) in extravirgin ($41.53{\pm}3.93$) compared to refined virgin olive oils ($7.29{\pm}2.56$). All classes of phenolics were shown to be potent antioxidants. In future epidemiolgic studies, both the nature and source of olive oil consumed should be differentiated in ascertaining cancer risk.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.331-336
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• 2004

Changes in the level of metabolites in leaves and pods were examined with respect to the seed chemical composition in black soybean. There was no further increase in pod length after 42 days after flowering (DAF). Pod weight, however, persistently increase until 73 DAF, thereafter the weight was slightly lowered. The seed storage protein, however, increased drastically as the increasing rate of pod weight was lessened at 61 DAF. The accumulation of seed storage proteins was occurred conspicuously as the increasing rate of pod weight was slowed down. The chlorophyll content both in leaves and pods was drastically decreased after 50 DAF. The beginning of drastic reduction in chlorophyll content was occurred concomitantly with the reduction of soluble protein content in leaves. The sugar content in leaves showed similar tendency with chlorophyll and soluble protein content. The starch level in leaves, however, showed different changing pattern during seed development. The starch content in leaves was increased persistently until 66 DAF, thereafter the content was decreased drastically to about $55\%$ of maximal value at 66 DAF. Total phenolics content in leaves and the anthocyanins content in seeds were stable without noticeable increase until 66 DAF. The contents were increased dramatically after 66 DAF showing the synchronized pattern with the decrease in starch level in leaves. The levels of the selected metabolites in leaf and seed suggested that the accumulation of chemical components of black soybean seed is launched actively at 66 DAF. The profile of storage proteins was nearly completed at 61 DAF because there was no large difference in densitometric intensity among protein subunits after 61 DAF. In soybean, chemical maturation of seed begins around 61 to 66 DAF at which most metabolites in vegetative parts are decreased and remobilized into maturing seeds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.315-320
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• 2006

For the purpose of developing natural antioxidant, the antioxidative and antimicrobial activities of phenolics isolated from spices were determined. The total phenolics contents of spices were more than 20 mg/g in water and 60% ethanol extracts of all spice, oregano and sage. Electron donating ability assay showed high inhibition rate in water extracts of all spice, nutmeg, white pepper, oregano and sage and 60% ethanol extracts of oregano and nutmeg. Antioxidant protection factor (PF) was higher than 1.2 in 60% ethanol extracts of sage, all spice and oregano and water extracts of sage. The 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical decolorization (ABTS) was inhibited by more than 90% by water and 60% ethanol extracts of all spice and oregano. TBARS (thiobarbituric acid reactive substances) were $0.7{\mu}M$ in the control and $0.2{\mu}M$ in water and 60% ethanol extracts the each spices. The water extracts of each spices did not have antimicrobial activity against H. pylori; however, the 60% ethanol extracts from oregano revealed the high antimicrobial activity as clear zone of 10 mm and inhibition rate of 77.2% with $200{\mu}g/mL$ of phenolics content. The result suggests that spices extract may be useful as potential sources of anti-Helicobacter pylori, antioxidant.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.82-86
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• 2009

The objective of this study was to evaluate the effect of various solvents on extraction of bioactive phenolics and to analyze the antioxidant capacity and contents of individual catechins in various grades of green teas organically grown in Boseong, Korea. The organic green teas, based on their harvest seasons, were categorized into five grades such as Woo-Jeon, Se-Jak, Jung-Jak, Dae-Jak, and coarse tea. Solvents used to extract phenolics from these teas included water at $23^{\circ}C$ and $70^{\circ}C$ as well as 80% (v/v) aqueous methanol and ethanol. In general, aqueous organic solvents of methanol and ethanol led to higher extraction yields of phenolics than water at $23^{\circ}C$ and $70^{\circ}C$. Total phenolics and antioxidant capacity of the teas extracted with the aqueous organic solvents were approximately 1.5 to 3.2 and 1.8 to 3.8 times higher than those with water at $23^{\circ}C$ and $70^{\circ}C$, respectively. Coarse tea, the lowest grade of green tea, showed approximately 30-60% lower total phenolics and antioxidant capacity compared with the higher grade ones. Reversed-phase HPLC analysis was performed quantitatively to identify individual catechins, gallic acid, and caffeine in teas extracted with 80% (v/v) aqueous methanol. Based on their dry weights, the organic green teas contained about 1.7 to 2.9% of caffeine. Content (mg/g dry weight) of tea catechins decreased in the following order: Woo-Jeon (155.4) > Se-Jak (147.7) > Jung-Jak (143.2) > coarse tea (135.1) > Dae-Jak (130.5). (-)-Epigallocatechin gallate was the most abundant among the catechins analyzed. The highest grade of green tea, Woo-Jeon, had the highest amount of (-)-epigallocatechin gallate at 77.4 mg/g dry weight. Overall, the higher grade of organic green teas tended to have the higher level of antioxidant capacity and catechins.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.580-584
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• 2007

Actinidia arguta extracts obtained from three cultivars ('Sae-Han', 'Dae-Sung', and 'Chil-Bo') were assayed for their antioxidant properties and nutritional composition. Antioxidant activity of the extracts was evaluated using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. Total phenolic contents of the extracts were determined by the Folin-Ciocalteu method. Vitamin C (L-ascorbic acid) content measured by a colorimetric method and reducing sugar content estimated by dinitrosalicylic acid (DNSA) method. Crude extracts from A. arguta 'Sea-Han' showed the most potent radical-scavenging activity showing 86.55% at 10 mg/ml. The DPPH radical scavenging activity of extracts and solvent fractions from Sea-Han cultivar was in decreasing order of EtOAc fraction>BuOH fraction>$CH_2Cl_2$ fraction>hexane fraction, among which EtOAc fraction showed the highest antioxidant activity (87.51 % at 5 mg/ml). Total phenolic contents in A. arguta 'Sae-Han', 'Dae-Sung' and 'Chil-Bo', were 32.93, 28.23, and 25.60 mg/g, respectively. Vitamin C contents of them were 840.57, 578.81 and 730.10 ug/g, respectively.

• Korean Journal of Plant Resources
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• v.27 no.6
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• pp.629-634
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• 2014

Rice type tartary buckwheat is used as a substitute for rice in many Asian countries due to its easy dehulling character. The objective of the present study was to determine the chlorophyll, total polyphenol (TP), total flavonoid (TF), antioxidant activity and to quantify the bioactive compounds rutin, quercetin and chlorogenic acid in the seedlings of rice-type tartary buckwheat (RTTB). Young seedlings exhibited higher antioxidant (DPPH radical inhibition) activity in dose dependent manner. TP and TF content were highest ($3017.46{\pm}201.84{\mu}g$ TAE/100 mg dw and $1916.0{\pm}102.95{\mu}g$ QE/100 mg dw respectively) in 3 days after germination (DAG) seedlings compare to 6 and 9 DAG. The contents of rutin and quercetin increased with growing stage of seedlings. However, the chlorogenic acid decreased with increasing growth. Overall, RTTB seedlings can be regarded as a strong source of phenolics and have high possibility for food and nutraceutical application due to their efficient antioxidant properties, higher chlorophyll and phytochemical content.

• Korean Journal of Agricultural Science
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• v.43 no.5
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• pp.723-733
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• 2016

Soybeans [Glycine max (L.) Merill] are a rich source of antioxidants and other phytonutrients. Soybean sprouts contain many biologically active secondary metabolites and are rich in polyphenols, flavonoids, and phenolic compounds. In the present study, two soybean cultivars, Hosim, with high oleic acid (- 80% in total seed oil), and Pungsannamul, with normal oleic acid (- 23%) in seed, were examined for changes in the content of crude protein, crude oil, total flavonoids, total phenolics, and DPPH (1,1-diphenyl-2-picryl-hydrazyl) during the sprouting duration of 5 days. The protein content in both the varieties was found to increase by the days of sprouting. The crude oil content of Pungsannamul sprouts was found to be maximum on day 1 (16.9%, w/w) and decreased thereafter to reach to the level of 14.8% on day 5. No significant differences in the crude oil content of Hosim sprouts from day 1 to 5 were observed. Flavonoid content was found to increase up to day 4 and then dropped on day 5, in both the cultivars. Total polyphenol content showed a tendency to increase up to day 3 and started to decrease significantly from day 4. DPPH activity was found to increase up to day 5 in both the varieties. All the components studied in the high oleic acid soybean sprouts showed a change in content during the sprouting process similar to the change that would occur in normal oleic acid soybeans. The study showed that the contents of antioxidant, flavonoid, and polyphenol significantly increase during the sprouting.

• Journal of the Korean Society of Food Culture
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• v.30 no.1
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• pp.77-85
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• 2015

This study investigated the physicochemical properties and antioxidative activity of soymilk added with buckwheat sprout (SBS), and sensory properties of SBS were analyzed with control soymilk (CS). Moisture content decreased while protein, ash, and lipid contents increased according to content of buckwheat sprout. Solids content and viscosity tended to increase with addition of buckwheat sprout from 0% (CS) to 2.5% (2.5SBS), 3.5% (3.5SBS), and 4.5% (4.5SBS). SBS was found the significant pH drop from 7.08 to 6.43, 6.34, and 6.21. Suspension stability of soymilk slightly decreased with addition of buckwheat sprout. Hunter's color value L of SBS decreased while a and b values increased in comparison with CS. Rutin content was measured 23.78 mg/100 g (2.5SBS), 39.68 mg/100 g (3.5SBS), and 44.80mg/100 g (4.5SBS). Vitamin C content in SBS was higher than CS. Daidzin content increased as buckwheat sprout was added. Total phenolic content increased from 100.95 mg/100 g (CS) up to 315.71 mg/100 g (4.5SBS). For free radical scavenging activity, SBS was significantly higher than CS. In conclusion, SBS can be used as a functional food with higher amounts of rutin, vitamin C, total phenolics, and daidzin. 2.5SBS and 3.5SBS also showed better overall quality characteristics.