본 연구는 paclobutrazol(PBZ) 처리에 따른 호접란의 생장 반응과 화경유도를 확인하기 위해 수행되었다. 20°C 생식생 장 환경에서 호접란 ‘Mantefon’과 ‘V3’ 실험묘를 0, 100, 200, 400ppm(유효성분 0, 1, 2, 4mg) PBZ 농도로 처리하였고, 28°C 영양생장 환경에서 ‘Mantefon’ 실험묘를 0, 100, 200ppm(유효성 분 0, 1, 2mg) PBZ 농도로 처리하였다. 화경유도 환경에서는 200, 400ppm 처리 식물들의 화경유도율이 감소하고 화경의 출 현이 늦어지는 것을 관찰하였다. 또한 ‘Mantefon’에서 처리 농도 에 상관없이 모든 PBZ 처리구에서 화경의 수가 감소하였다. PBZ 처리는 화경의 길이도 감소시켰으나 개화소요일수나 소화 의 수에는 차이가 없었다. 한편, 영양생장 환경에서는 처리 농도 가 증가할수록 줄기와 뿌리 직경, 잎의 두께는 증가하였고, 반면 에 신엽의 수, 잎의 길이와 폭은 감소하였다. 따라서 PBZ 처리를 받은 식물에서 ‘stunting’ 현상이 나타났다. 영양생장 환경에서 PBZ 처리를 받은 식물을 생식생장 환경으로 옮겼을 때도 앞선 실험에서와 마찬가지로 화경유도율이 감소하고 화경출현일수 가 증가하여서 영양생장 동안의 PBZ 처리 효과가 화경유도에까 지 이어질 수 있다는 것을 확인하였다. 이러한 결과를 통해 PBZ 처리는 호접란의 생장과 화경유도를 제한할 수 있다는 것을 알 수 있었다.

This study assessed yearly trends of food and nutrient intake among high school students aged 16 to 18 years (n=2,377) using the 2007~2015 Korea National Health and Nutrition Examination Survey (KNHANES). Yearly trends of food or nutrient intake were analyzed via logistic regression analysis. The results showed that consumption of sugars & sweets, and beverages & alcohols was increased rapidly during this period (p<0.0001). Intake of meat & meat products, and fish & shellfish also was increased (p=0.0008). Intake of grains and grain products was increased until year 2011 but declined after 2012 (p=0.0025). Consumption of vegetables, and milk & milk products was decreased (p=0.0395). Intake of protein, fat, thiamin, riboflavin, niacin, and iron was increased (p=0.0445). Carbohydrate energy ratio was decreased, whereas fat energy ratio was increased (p=0.0235). Most nutrient intakes satisfied the dietary reference intakes for Koreans except dietary fiber (19.6~26.2%), calcium (46.9~55.2%) and sodium (more than 221.4%) during this period. There was a significant positive correlation between most food group intakes and most nutrient intakes (p=0.0468). Therefore, it is crucial to increase dietary fiber and calcium intake and decrease consumption of sugars, fats and sodium through diverse eating of food groups to ensure balanced nutrition of subjects.

This study was performed to investigate how changing the period of light and dark influences the vegetative growth and the photosynthesis of Doritaenopsis Queen Beer ‘Mantefon’. Clones of Dtps. Queen Beer ‘Mantefon’ at 4-month-old stage were grown in a closed-plant factory system with four different light/dark cycles; 06/06 h, 08/08 h, 10/10 h, and 12/12 h. Temperature and relative humidity were set at 28oC and 80%, respectively, with a photosynthetic photon flux density of 160 ± 10 μmol·m-2·s-1. Repetitive measurements showed that the leaf length and the leaf width were the longest under 12/12 h closely followed by 10/10 h. The fresh weight and the dry weight of leaves and roots were the heaviest at 10/10 h treated samples. Different CO2 uptake patterns were observed from different light/dark cycles. Under 10/10 h and 12/12 h treatments, the CO2 uptake started at early dark period. When the light/dark cycles were shortened to 06/06 h and 08/08 h, the CO2 uptake started at the middle of dark period. Total CO2 uptake amounts were the highest under 12/12 h treatment followed by 10/10 h, 06/06 h, and 08/08 h treatments. Quantitative measurements showed that the vegetative growths under 10/10 h treatment were comparable with that of 12/12 h treatment. These studies indicated that manipulating light/dark can modify the photosynthesis patterns and vegetative growth of Dtps. Queen Beer ‘Mantefon’, resulting in the reduction of the production period.

The influence of aging on the flavor precursors and volatile compounds of top round beef was studied. The concentrations of free amino acids, nucleotides, creatine, dipeptides, and volatile compounds were measured after top round from Hanwoo was aged at 4℃ for 21 days. The amount of free amino acids in top round significantly increased with the increase of aging period. There was no effect of aging on the concentrations of adenosine monophosphate or inosine in top round. The inosine monophosphate content of top round significantly decreased with age, while the hypoxanthine content increased. The concentrations of creatine, carnosine, and anserine in top round were not influenced by aging. In total, 24 volatile compound were identified in aged, cooked top round. Of these, the quantities of aldehydes (propanal, pentanal, hexanal, heptanal, octanal, and nonanal), hydrocarbons (pentane and octane), 2-butanone, ethyl acetate, and pyridines (4-ethynyl-pyridine and 4-acetyl-pyridine) significantly increased after aging. We conclude that the flavor of top round can be improved by aging.

The purpose of this study was to estimate usage of vitamin and mineral supplements as over-the-counter (VM-OTC) drugs as well as examine factors associated with VM-OTC usage in Korean adolescents. A total of 1,407 adolescents attending middle or high school in all parts of country were included in the analysis. Prevalence of VM-OTC usage was 56.1%, and it was higher as monthly income, father’s education level, and socioeconomic status of family increased (p<0.001). VMOTC intake was higher in middle school students than in high school students as well as in rural areas or small & mediumsized city residents than big city residents (p<0.01). Subjects mainly received information on VM-OTC mainly from ‘family and relatives’ (46.6%), whereas only 20.3% received information from experts. Subjects took VM-OTC ‘when they are healthy’ (49.1%), ‘when they feel sick’ (17.7%), ‘when they are on a diet’ (17.3%), and ‘when they are stressful’ (15.9%). The effectiveness of taking VM-OTC were mainly ‘fatigue recovery’ (35.0%), ‘health improvement’ (30.6%), and ‘nutritional status improvement’ (13.2%). The most frequently used VM-OTC was vitamin C (49.1%), multi-vitamins (18.6%), multi vitamins & minerals (13.2%), and calcium (9.2%). Among VM-OTC users, only 21.9% replied that they usually check the nutrition facts when they buy products, 62.4% follow the recommended dosage, and 9.7% fully understand the nutrition labels of the products. According to logistic regression analysis, the most influential factor affecting VM-OTC use was parents’ and siblings’ VM-OTC consumption (p<0.001). In addition, school type (middle or high school) (p<0.01), residence (p<0.05), self-concerns about health (p<0.05), father’s education level (p<0.05), and socioeconomic status of family (p<0.05) all influenced VM-OTC use. These results show that VM-OTC use is widespread among adolescents, few users actually check and fully understand the nutrition labels when they purchase VM-OTC, and they are highly dependent on unprofessional advice and information. Therefore, it is necessary to educate adolescents to help them select proper VM-OTC and read nutrition labels.