• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.53 no.3
• /
• pp.333-338
• /
• 2008

The tea has traditionally been used as a foodstuff by unique flavor, however recently not only the diversity of consumer demands but also the public interest in unique favorite and functional aspects have increased. It has been also reported that the main components contained in the leaves of tea (Camellia sinensis) include total nitrogen, free amino acids, polyphenols, and fiber, of which catechin has powerful bioactive effect such as anti-cancer, anti-aging, and anti-diabetic. (-)-Epigallocatechin gallate (EGCG) which is a major phenolic constituent of green tea extract has received considerable attention for a variety of important bioactivities. This study was carried out to obtain useful information for tea breeding programs, and to investigate the concentration of quality and functional related components in Korean indigenous tea germplasms. Korean indigenous tea lines were classified into three groups of sprout time, i.e, early, medium and late sprout time, and the ratio were 20%, 43% and 37%, respectively. There was a difference in characteristics among these Korean indigenous tea lines, leaf width of those ranged from 19.8 to 75 mm, leaf length was 35.5-160.0 mm, and leaf area was $660-8,400\;mm^2$. Experimental data on chlorophyll content (SPAD value) of Korean indigenous tea genetic resources ranged from 51.3 to 82.3. The concentrations of the total nitrogen, total free amino acids, and theanine were ranged 4.18-6.07%, 2.87-4.58%, and 1.64-2.66%, respectively. Also, catechin concentration showed from 11.54 to 15.07%, and concentration of caffeine was 2.82-4.23%. These results indicated indicated that it is possible to select elite lines with high concentration of quality related components and low concentration of caffeine from Korean domestic tea germplasms.

• Biomolecules & Therapeutics
• /
• v.13 no.2
• /
• pp.107-112
• /
• 2005

Excessive drinking causes 'alcohol hangover' within 8-16 hours. The cause of 'hangover' has not been elucidated exactly until now, but it is reported that it is caused by the creation of blood ethanol and acetaldehyde as ethanol metabolites. In this study vinegar extract of wood (VE) or OC-1, to which the powder extract of green tea leaves extract is added, was administered to the rats 30 minutes before the oral administration of ethanol (3 g/kg) and the blood ethanol and acetaldehyde concentration was measured in order to evaluate the efficacy of the beverage material for detoxification. As a result, the blood ethanol concentration in the group of the VE-1(vinegar crude extract) and VE-2 (double diluted solution) is statistically lower (P,0.05) than the exclusive alcohol administered control group. The blood acetaldehyde concentration of all groups of VE and OC-2, which is the double dilution of OC-1, is statistically low after 7 hours following ethanol administration. Especially, the AUC value of OC-2 group is statistically low compared to the control group. Accordingly, it indicates the conclusion that VE and OC-1, reducing the blood ethanol and acetaldehyde concentration which are two leading factors of 'hangover' after drinking, and worthwhile to be developed as beverage materials to eliminate 'hangover'.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.4
• /
• pp.335-341
• /
• 2019

Beta-carotene is the most prominent member of the group of carotenoids, natural colorants that occur in the human diet. Beta-carotene is also an effective source of vitamin A in both conventional foods and vitamin supplements, and it's generally safe. In this study, we explored the beta-carotene contents in agricultural products widely and specifically grown in Korea. The beta-carotene contents were ranging from 223 to $27,908{\mu}g/100g$ in leaves, and 0 to $7,588{\mu}g/100g$ in vegetables. In leaves and vegetables, the amount of beta-carotene was the highest in green tea powder ($27,908{\mu}g/100g$), followed by pepper ($7,588{\mu}g/100g$). In fruits, the beta-carotene content was found to range from $0{\mu}g/1,011g$ to maximum of $293.66{\mu}g/100g$(plumcot). However, there beta-carotene was not detected in strawberry. In the case of cereals and specialty crops, the beta-carotene contents were $326{\mu}g/100g$ for non-glutinous rice, $313{\mu}g/100g$ for glutinous rice, $57{\mu}g/100g$ for amaranth and $15{\mu}g/100g$ for pine nut, respectively. However, the beta-carotene content was not detected in other samples. This study revealed the presence of beta-carotene content in agricultural products specifically grown in Korea for nutritional information and food composition database.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.1
• /
• pp.65-77
• /
• 2020

In order to industrialize of Dendranthema indicum (L.) DesMoul., which is a lot of commercially available and is synonymous with chrysanthemum tea, in the autumn of 2018, Dendranthema indicum (L.) DesMoul. seeds were collected from its own native region, and the seeds were germinated after refrigerated storage. Young seedlings were subjected to experiments in February, March, and April in the open field to examine the effects on the harvesting of leaves by distance and the growth of leaves and stems. The results of analyzing the components by collecting the leaves+stem after collecting the flower of Dendranthema indicum (L.) DesMoul. are as follows. 1. When D. indicum (L.) DesMoul. seedlings were planted according to the transplanting date, the number of flowers was 17.1 in the transplanting date in April. The diameter of the flower was 2.9cm, 16ea, 6.5~6.6g in the fresh weight, and the dry weight of the case was 1.1~1.2g. The leaves were 46~47ea in March and April in the planted area, 5.2~5.3cm in leaf length and 3.5~3.6cm in leaf width. 2. When planted D. indicum (L.) DesMoul. seedlings according to transplanting distance, the number of flowers was 16.2 when planted at 20×20cm intervals and, 16.8~17.1 at 30×30~50×50cm intervals. The diameter of the flower was 2.7~2.8cm, the number of petals was 8, the length of the petal was 0.8 cm, and fresh weight was 6.5~6.6g per flower. Leaves had the largest number of 47 of 30×30cm and 40×40cm, and leaf length appeared at the longest 6.2cm in the 50×50cm treatment area, but 5.2cm in the other treatment areas. 3. The extraction yield of D. indicum (L.) DesMoul. leaves+stems was 7.93%, and the extraction solvent colors were light green at 50, 60% and green at 70, 80, 90, 100%. The extraction yield of D. indicum (L.) DesMoul. flowers was 7.58%, the color of the extraction solvent was light yellow at 50, 60 and 70%, yellow at 80 and 90%, and dark yellow at 100%. 4. We confirmed 11 kinds of ingredients such as in D. indicum (L.) DesMoul. flowers are gallic acid, 4-hydroxy benzoic acid, methyl gallate, 4-hydroxy-3-methoxy benzoic, caffeic acid, salicylic acid, p-coumaric acid, sinapic acid, naringin, 4-melthoxyben, flavone. The content was 29.200-36.900ppm. 5. The components contained in the D. indicum (L.) DesMoul. leaf+stem, salicylic acid appeared at 6,129.526ppm, and the next 4-methoxyben was 1,966.714ppm. It was methyl gallate 8.197ppm, 4-hydroxy-3-methoxy benzoic 6.994ppm, caffeic acid 5.566ppm, flavone 4.522ppm, p-coumaric acid 3.787ppm, gallic acid 1.893ppm that appeared in the content below 10ppm.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.1162-1162
• /
• 2001

Whereas NIR spectroscopy has been applied in agriculture for more than 20 years, few studies refer to those plant substances occurring only in smaller amounts. Nevertheless there is a growing interest today to support efficiently activities in the production of high-quality medicinal and spice plants by this fast and non-invasive method. Therefore, it was the aim of this study to develop new NIR methods for the reliable prediction of secondary metabolites found as valuable substances in various plant species. First, sophisticated NIR methods were established to perform fast quality analyses of intact fennel, caraway and dill fruits deriving from single-plants [1]. Later on, a characterization of several leaf drugs and the corresponding fresh material has been successfully performed. In this context robust calibrations have been developed for dried peppermint, rosemary and sage leaves for the determination of their individual essential oil content and composition [2]. A specially adopted NIR method has been developed also for the analysis of carnosic acid in the leaves of numerous rosemary and sage gene bank accessions. Carnosic acid is an antioxidative substance for which several health promoting properties including cancer preservation are assumed. Also some other calibrations have been developed for non-volatile substances such as aspalathin (in unfermented rooibos leaves), catechins (in green tea) and echinacoside (in different Echinacea species) [3]. Some NIR analyses have also been successfully performed on fresh material, too. In spite of the fact that these measurements showed less accuracy in comparison to dried samples, the calibration equations are precise enough to register the individual plant ontogenesis and genetic background. Based on the information received, the farmers and breeders are able to determine the right harvest time (when the valuable components have reached their optimum profile) and to select high-quality genotypes during breeding experiments, respectively. First promising attempts have also been made to introduce mobile diode array spectrometers to collect the spectral data directly on the field or in the individual natural habitats. Since the development of reliable NIRS methods in this special field of application is very time-consuming and needs continuous maintenance of the calibration equations over a longer period, it is convenient to supply the corresponding calibration data to interested user via NIRS network. The present status of all activities, preformed in this context during the last three years, will be presented in detail.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.3
• /
• pp.418-424
• /
• 2015

The content of ${\beta}$-carotene in agricultural foods, such as seasonings, tea, vegetables, cereals, nuts & seeds, oils & fats, and fruits, were quantitatively analyzed using reversed-phase HPLC with an UV/visible detector. Standard reference material (SRM) 2385 was used as a control material to validate measurement of ${\beta}$-carotene in this study. Recovery percentage and relative standard deviation of ${\beta}$-carotene in SRM 2385 were 102% and 1.73%, respectively. Vegetables and tea contained relatively high concentrations of ${\beta}$-carotene (young barley powder, $17,293.95{\mu}g/100g$; raw young barley, $2,755.15{\mu}g/100g$; dried green tea leaves, $13,671.85{\mu}g/100g$; green tea powder, $7,579.04{\mu}g/100g$). Contents of ${\beta}$-carotene in nuts & seeds as well as oils & fats ranged from $11.32{\mu}g/100g$ in almond products (roasted with salt) to $58.56{\mu}g/100g$ in perilla seed oil. Among 20 fruits, a high content of ${\beta}$-carotene was found in apricots (raw), which contained $2,280.35{\mu}g/100g$.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.8
• /
• pp.1070-1076
• /
• 2007

Soymilk cake (SMC) fortified with defatted soy flour was fermented by a novel Bacillus subtilis GT-D in the solid-state fermentation with chlorella, mulberry leaves or green tea as food ingredient. The fermentation of SMC resulted in higher content of tyrosine and higher activities of protease, amylase and fibrinolytic enzymes. Fermented SMC including mucilage indicated six-fold higher content of dietary fiber compared to that of non-fermented SMC. The SMC fermented without additional ingredient allowed the highest spread ratio and width of cookies. Cookies prepared without SMC showed the lowest value of spread ratio and width compared to those of fermented SMC. In addition, these cookies showed the highest hardness value of 8,975 g, and thickness value of 5.97 and slightly higher bright color. Cookies fortified with SMC fermented with chlorella or mulberry leaves showed higher sensory evaluation value. Fortification of SMC fermented without additional ingredient resulted in the highest preference in the sensory evaluation of cookies.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.5
• /
• pp.785-792
• /
• 2020

ʟ-Theanine, found in green tea leaves has been shown to positively affect immunity and relaxation in humans. There have been many attempts to produce ʟ-theanine through enzymatic synthesis to overcome the limitations of traditional methods. Among the many genes coding for enzymes in the ʟ-theanine biosynthesis, glutamylmethylamide synthetase (GMAS) exhibits the greatest possibility of producing large amounts of production. Thus, GMAS from Methylovorus mays No. 9 was overexpressed in several strains including vectors with different copy numbers. BW25113(DE3) cells containing the pET24ma::gmas was selected for strains. The optimal temperature, pH, and metal ion concentration were 50℃, 7, and 5 mM MnCl₂, respectively. Additionally, ATP was found to be an important factor for producing high concentration of ʟ-theanine so several strains were tested during the reaction for ATP regeneration. Baker's yeast was found to decrease the demand for ATP most effectively. Addition of potassium phosphate source was demonstrated by producing 4-fold higher ʟ-theanine. To enhance the conversion yield, GMAS was additionally overexpressed in the system. A maximum of 198 mM ʟ-theanine was produced with 16.5 mmol/l/h productivity. The whole-cell reaction involving GMAS has greatest potential for scale-up production of ʟ-theanine.

• Applied Biological Chemistry
• /
• v.47 no.1
• /
• pp.72-77
• /
• 2004

The purpose of this research was to determine the effect of phenol compounds from green tea leaves and surfactant micelles on lipid oxidation in com oil-in-water emulsion (O/W). The concentration of phenol and surfactant in continuous phase of the O/W with exceed Brij 700 and phenol compounds was measured. The particle size of O/W with phenol (100 ppm) increased with increasing added exceed surfactant $(0{\sim}2.0%)$ and the concentration of surfactant and phenols in the continuous phase higher than these of control. Lipid oxidation rates, as determined by the formation of lipid hydroperoxides and headspace hexanal, in the O/W emulsions containing phenol compounds (100 ppm) and exceed surfactant $(0{\sim}2.0%)$ decreased with increasing concentration of exceed surfactant. The ability of the phenol compounds and exceed surfactant to inhibit hydroperoxide and headspace hexanal producing as lipid oxidation in O/W was BHT>procyanidin B3-3-O-gallate> (+)-gallocatechin > (+)-catechin and 2% > 1 % > 0% of exceed surfactant. These results indicate that phenol compounds and exceed surfactant could alter the physical location of hydroperoxide in O/W.

• Journal of Appropriate Technology
• /
• v.5 no.2
• /
• pp.91-96
• /
• 2019

Microalgae do not require much land and make a higher efficient oil production. However, it costs still much higher than other biodiesel resources, such as crops. Sugars charge 80% of culture media when microalgae are massively cultured in the fermenter. This study aims to develop a cost-efficient process for sugar production from Chinese cabbage byproducts. Pre-treatment with 0.25% H₂SO₄ was most effective when chopped cabbage was incubated 50℃/130 rpm for 24 hours. To hydrolyze cabbage cellulose, we used cellulases secreted from Trichoderma. harzianum. T. harzianum was cultured at 28℃/pH 7/130 rpm for five days. Optimal enzymatic activity of cellulase was obtained by incubating at 0.24 FPU/ml/45℃/pH 5/130 rpm for three days. In comparison to other agricultural waste, such as rice straw, green tea leaves, and palm residue, Chinese cabbage produced the highest sugar yield. We found the optimal conditions to produce sugar from Chinese cabbage byproducts as a carbon source to culture biodiesel-producing microalgae. The efficient process developed in this study helps microalgae as a sustainable alternative energy source by cost-down.