식물의 이차 대사산물은 다양한 생물활성을 가지며 자외선은 이차 대사산물의 생성에 영향을 미치는 것으로 알려져 있다. 뽕나무는 다양한 종류의 유용 성분을 함유하여 활용가치가 높은 식물 중의 하나이다. 본 연구에서는, UV 조사에 따른 뽕나무 잎의 이차 대사산물의 변화를 조사하기 위하여, 뽕나무 잎을 LC-MS를 이용하여 무표적 분석법으로 분석하였으며, 무표적 분석으로 얻은 scan data를 bioinformatics 프로그램인 R의 XCMS package를 이용하여 profiling 한 결과, 적어도 35종 이상의 화합물에서 UV-C 조사에 따른 양적인 변화가 발견되었다. 이들 중 14종의 화합물은 분리 및 NMR spectrum 비교 또는 표적 분석을 통하여 종류를 확인하였으며, 종류가 확인된 성분에 대해 정량분석을 수행한 결과, morin(464배), oxyresveratrol(256배), 2,3-trans-dihydromorin(170배), 2",4",2,4-tetrahydroxychalcone(120배), catechin(84배), 4"-prenyloxyresveratrol(43배), moracin M(35배) 등의 함량이 현저하게 증가한 것으로 나타났다. 또한 UV-C를 조사한 뽕나무 잎은 대조구에 비하여 항산화 활성이 2.1-2.4배, tyrosinase 억제 활성이 2.3배 증가한 것으로 조사되었다. 이러한 조사 결과는 자외선의 조사가 뽕나무 잎의 기능성을 향상시켜 기능성 식품, 약용 또는 화장품 소재로서의 활용 가치를 향상시키는 유용한 수단이 될 수 있음을 보인다.

Ergocalciferol is known as having vitamin D activity. In this study, the effects of UV irradiation on the increase of egocalciferol content were investigated in 7 kinds of mushrooms, i.e, lily mushroom (Flammulina velutipes), oyster mushroom (Pleurotus ostreatus), young oyster mushroom (Pleurotus ostreatus), king oyster mushroom (Pleurotus eryngii), button mushroom (Agaricus bisporus), shiitake (Lentinula edodes), and wood ear mushroom (Auricularia auricula-judae). Mushrooms which were not exposed to UV light contained negligible amount of ergocalciferol in all kinds of tested mushrooms, but UV irradiation increased their content of ergocalciferol. Of UV A, B and C, UV B light was the most effective to increase ergocalciferol contents. In mushrooms, the increase in ergocalciferol content occurred only in the peel within 1 mm depth from the surface, which was directly exposed to the UV light. Therefore, when fresh whole mushrooms were irradiated with UV light, lily mushroom, the mushroom with a larger surface area compared to volume, such as lily mushroom, was more favorable in producing ergocalciferol. On the other hand when the mushrooms were freeze-dried and cut, the mushrooms with a higher ergosterol, such as king oyster mushroom, shiitake or button mushroom, were more favorable in generating ergocalciferol.

수확 후 돌나물의 미생물학적 안전성 확보를 위해 1% acetic acid 침지 세척과 10 kJ/m2 UV-C 조사를 병합처리하여 10°C에서 6일간 저장하면서 미생물 수, 색도, 비타민 C 함량, 항산화능을 측정하였다. 돌나물에 병합처리 후 총 호기성 세균 수는 대조구와 비교하여 3.28 log CFU/g, 효모 및 곰팡이에서는 4.22 log CFU/g 감균 효과를 보였으며, 이러한 효과는 저장 6일 동안 유지되었다. Acetic acid와 UV-C 병합처리는 대조구와 비교하여 돌나물의 저장 중 Hunter 색도 값에 부정적인 영향을 끼치지 않았다. 또한 비타민 C 함량과 항산화능은 저장기간 동안 처리구와 대조구 모두 감소하였으나, 처리에 의한 차이는 없는 것으로 나타났다. 따라서 본 연구 결과 acetic acid와 UV-C 병합처리가 수확 후 돌나물의 저장, 유통 시 미생물학적 안전성을 확보하고 품질 유지에 효과적인 hurdle technology라고 판단된다.

This study was conducted to evaluate the changes in the quality of rice wine (Makgeolli) treated with UV-C and electron beam (EB) irradiation during its storage at 4℃ for 15 days. The EB irradiation was found to be more effective than the UV-C irradiation for microbiological control. The pH tended to be increased by UV-C, EB irradiation, and storage period. Acidity was significantly higher in rice wine treated with EB irradiation than those of control and UV-C irradiation during storage period. The L*-value of the samples treated with UV-C and EB irradiation tended to be proportionately higher than that of the control, but this was not consistent during storage period. The a*-value of the sample treated with EB was higher than that of the others, but this was not consistent during the storage period. The reducing sugar content was higher in the control at day 0, but it rapidly decreased compared with the control during the storage. The results indicate that EB irradiation was more effective than UV-C irradiation in controlling microorganisms of rice wine. However, a further study is needed to minimize the rice wine quality deterioration caused by UV-C or EB irradiation during storage.

UV light irradiation is known to give beneficial effects on fresh produce preservation. A container system equipped with UV-LED was fabricated for storing cherry tomatoes under computer-controlled conditions of intermittent on-off cycles (1 hour on/1 hour off). Wavelength (365 and 405 nm) and physical location of the LED (2 and 5 cm above fruit) were studied as variables affecting the respiration, ethylene production and quality preservation of the fruits at 10 and 20℃. 365 nm wavelength gave much higher radiation intensity than 405 nm, and intensity on surface decreased in inverse proportion to square of distance from LED. When compared to non-irradiated control, UV-LED irradiation decreased the respiration by 5-10% at 10℃ while there was no obvious effect at 20℃. Ethylene production was reduced when the fruits were placed at 5 cm distance, while there was no significant difference from control at 2 cm location. The reduction of ethylene production at 5 cm was more pronounced at 20℃. UV-LED irradiation was shown to have delayed increase or lower concentration in carotenoids compared to control treatment. Any negative effect of UV-LED irradiation on ascorbic acid content and firmness was not observed.

햄버거 패티에 L. monocytogenes cocktail을 인위적으로 접종한 후 UV-C 조사 처리에 따른 저장 중 미생물 수 변화를 조사하였다. 햄버거 패티에 접종된 L. monocytogenes의 초기 균수가 6-7 log CFU/mL가 되게 하였고, 사용된 UV-C 조사선량은 1, 5, 10 kJ/이었으며 조사된 시료는 에서 7일 동안 저장하였다. UV-C 조사는 L. monocytogenes 수에 있어서 조사선량이 증가할수록 유의적으로

Anthocyanin and polyphenolic compounds present in fruits of mulberry (Morus alba L.) were determined and the influence of temperature and UV irradiation on stability of the anthocyanin-copigment complex were investigated. The copigmentation substance selected in non-anthocyanin fraction from mulberry for the study included: phenolic acid (hydroxybenzoic acid) and flavonoid (quercetin-3-O-β-D-glucopyranoside). The copigmentation effect increased with the copigment content. UV irradiation had a stronger degradation effect on the copigmentation complex than heating at 80℃. The non-anthocyanin fraction of mulberry and isolated flavonoid (quercetin-3-O-β-D-glucopyranoside) from mulberry fruit predominated over other copigment substances.

세척 당근에 E. coli O157:H7과 L. monocytogenes를 인위적으로 접종한 후 UV-C 조사 처리에 따른 저장 중 미생물수 변화를 조사하였다. 당근에 접종된 E. coli O157:H7과 L. monocytogenes의 초기 균수가 6-7 log CFU/mL가 되게하였고, 사용된 UV-C 조사선량은 1, 3, 5, 이었으며 조사된 시료는 에서 8일 동안 저장하였다. UV-C 조사는 E. coli O157:H7과 L. monocy

UV-C 조사가 고춧가루의 저장 중 미생물학적 변화와 품질에 미치는 영향을 연구하였다. 고춧가루에 UV-C 조사를 27, 54, 으로 처리한 후 에서 4 주간 저장하였다. UV-C 조사에 의해 고춧가루에 존재하는 오염된 미생물 수의 감소는 호기성 세균과 B. cereus에서 대조구 대비 각각 1.03, 0.90 log CFU/g 감소하였으며, 4주 저장기간 동안 초기 감균 효과를 유지하였다. UV-C 조사된 시료의 Hunter L, a, b 값

UV-C 조사가 국내에 유통되고 있는 수입 건어포류의 저장 중 미생물학적 변화와 품질에 미치는 영향을 연구하였다. UV-C 조사량은 5, 10, 으로 처리하여 대조구와 비교하였다. 조사시간은 5분 33초, 11분 6초, 22분 12초를 사용하였다. UV-C 조사에 의한 건어포류에 존재하는 오염된 미생물의 감소는 처리에서, 쥐포는 호기성 세균과 효모 및 곰팡이에서 각각 0.82, 1.23 log CFU/g, 문어포는 각각 1.20, 1.01 lo

본 연구에서는 모발의 내부 및 외부구조에 자외선이 미치는 영향에 관하여 조사를 수행하였다. 자외선이 조사된 모발의 형태학적 및 화학적 구조의 변화를 알아보기 위해 주사전자현미경(SEM), 투과전자현미경(TEM), 공초점레이져주사현미경(CLSM) 등을 사용하였다. SEM상에서 자외선이 조사된 모발은 자외선에 의한 화학적 산화반응에 의해 표면이 거칠고 부풀어진 형태를 보였다. 이황화결합(disulfide bond)의 산화에 의한 시스테인산(cysteic acid)의 분해로 팽윤부위가 관찰되었다. 또한 자외선 조사에 의해 표면색의 변화를 나타내었다. TEM 분석결과 버진헤어(virgin hair)의 경우에는 매끄러운 표면구조를 나타내었지만, 자외선 조사모발에 있어서는 거칠고 모수질층이 갈라진 형태를 보여주었다. 모피질층에 존재하는 멜라닌 입자의 크기가 감소하고 소실되는 것이 관찰 되었다. CLSM에 의해 3차원적 구조의 입체영상을 얻을 수 있었으며, 광학분할에 의해 버진헤어는 강한 형광을 나타내었지만, 자외선 조사모발은 낮은 형광을 보여주었다. 이는 버진헤어의 경우 자동형광을 나타낼 수 있는 방향족 아미노산이 많이 존재하는데 비해 자외선 조사모발은 방향족 아미노산이 파괴되어 낮게 나온 것으로 여겨진다.

To investigate the effect of culture conditions on growth and ginsenosides accumulation, we cultured the ginseng hairy root under three different media, white light or ultra-violet irradiation. The MS/B5 medium containning MS basal salt and B5 vitamin was good for the growth and ginsenoside accumulation. The light during the culture period of ginseng hairy root was irradiated. The growth was abundant in the ginseng hairy root cultured in dark. But the ginsenosides accumulation was higher than in the ginseng hairy root cultured in the light irradiation. When the ginseng hairy root was cultured in 20 L bioreactor, the ginsenosides accumulation was observed at 34% higher than the hairy root cultured in dark. UV irradiated the ginseng hairy root during the culture period. The long time irradiation of UV was caused decreasing the growth of ginseng hairy root, but the accumulation of ginsenosidess was increased as to the irradiated time.

Photodegradation of endosulfan alpha, beta, and sulfate known as the most toxic substance among organochlorine pesticides by UV irradiation was studied at experimental conditions such as different pH aqueous solution and reaction time. The initial concentration of endosulfan alpha, beta, and sulfate in aqueous solution was 500 ppb, respectively. The experiment of photodegradation was conducted in a quartz reactor equipped with a low pressure mercury lamp (100 W, 240 nm). The samples were withdrawn from the photo reactor at intervals of 0, 10 min, 30 min, 1 hr, 2 hr, and 4 hr. Endosulfan sulfate was never hydrolyzed and photodegraded in wide range of pH. At pH 5 and reaction time (240 min), endosulfan alpha was photodegraded up to 67%. Both endosulfan alpha and beta were started to photodegrade at pH 6.5 with the lapse of time, resulting in approximately 99.9% and 87.2% of photodegradation efficiency, respectively. Furthermore, at pH 9, endosulfan alpha and beta was partially hydrolyzed and photodegraded to 99.5% at 120 min of reaction time. During the photolysis, any photo-products of endosulfan alpha, beta, and sulfate were not observed.

PAHs are major pollutants that are widely distributed in soil and groundwater environment, so that may be regarded as carcinogens. We investigated the degradation kinetics of PAH in aqueous solution when low pressure UV energy and ultrasonic irradiation were applied. Phenanthrene and pyrene were used as model compounds. The degrees of degradation of these compounds with time were analyzed with a GC/MSD (SIM-mode). UV photolysis experiments showed that phenanthrene was reduced by 90～67% at initial concentrations of 1 ppm to 8ppm whilst it decreased to 50% at 10 ppm. Under the same conditions pyrene was degraded up to about 75% at lower initial concentrations but the reduction efficiency dropped to a level of 34 to 29% at the higher concentrations above 8 ppm. The reaction orders for phenanthrene and pyrene were found to be zero-th and ca. -0.4th order, respectively, thus implying that the reported assumption of pseudo 1st order reaction for some PAHs would be no longer valid. PAH degradation was roughly proportional to the intensity of UV (number of lamps), exhibiting maximum 92.5% of the degradation efficiency. The solution pH was lowered to 4.4 from 6.4 during the experiments partially because the carbons decomposed by the energy reacted with oxygen radicals to produce carbon dioxides. Ultrasonic irradiation on phenanthrene solutions gave relatively poor results which matched to 50 to 70% of degradation efficiency even at 2 ppm of initial concentration. Phenanthrene was found to be degraded more efficiently than pyrene for the two energy sources. Ultrasound also followed the same reaction kinetics as UV energy on PAH degradation.

The experiment was conducted to determine the effects of enhanced UV-B on growth and differential responses among cultivars in soybean. The soybean cultivars subjected to enhanced UV-B irradiation at daily dose of 11.32 kJ m^-2(UV-B_BE) revealed that the growth was significantly depressed. Plant height, leaf number, leaf area and dry weight were inhibited by UV-B irradiation showing differential responses among cultivars used. Danyeubkong seems to be less sensitive to the enhanced UV-B irradiation, while Keunolkong more sensitive. Reduction of chlorophyll content was also found significantly greater to Keunolkong. Specific leaf weight, an index of leaf thickness, and flavonoid content known as UV-absorbing compounds were significantly increased in Danyeubkong by UV-B, but those in the other cultivars were not significantly affected. The results indicated that there are cultivar differences in the growth and physiological responses to the enhanced UV-B irradiation and specific leaf weight and UV-absorbing compounds in the leaves were highly related to the sensitivity of soybean by UV-B irradiation.