• 제목/요약/키워드: Ultraviolet treatment

검색결과 455건 처리시간 0.024초

동결건조 목이버섯의 자외선(UVB) 처리조건에 따른 품질 특성 및 유효성분 함량 (Quality Characteristics and Content of Available Components of Freeze-dried Ear Mushroom by UVB (Ultraviolet B) Treatment Conditions)

  • 최소라;신소희;송영은;한현아;이송이
    • 한국식품영양학회지
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    • 제36권2호
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    • pp.129-136
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    • 2023
  • In order to investigate the optimal UVB (ultraviolet B) treatment conditions for vitamin D2 enhancement of freeze-dried ear mushroom, sample size (below 300 ㎛~whole), UV treatment temperature (30~60℃), treatment density (6.25~50.0 mg/cm2) and the samples mixing frequency (1~32 times) were treated differently. After that, chromaticity, vitamin D2 and ergosterol (vitamin D2 precursor) contents were investigated. As a result of the investigating, effective UVB treatment conditions for vitamin D2 enhancement are as follows. The sample sizes were 2~4 mm and finely crushed pieces. The treatment temperatures were 50℃ and 60℃. The treatment density was 12.5 to 25.0 mg/cm2, and the number of sample mixing was 8 times or more. As the amount of vitamin D2 increased by UVB treatment, the ergosterol content generally tended to decrease. However, under some UVB treatment conditions, the vitamin D2 content was not high despite the decrease of ergosterol content. Under the conditions set in this experiment, it was possible to obtain ear mushrooms with enhanced vitamin D2 up to 26,968.7 ㎍/100 g. Therefore, it is thought that the ear mushroom is highly likely to be used as a vitamin D source and nutritionally fortified food ingredient.

Aspergillus ochraceus와 Rhodotorula mucilaginosa 저감을 위한 자외선과 유기산 복합처리 효과 분석 (Analysis of the Reduction Effect of Combined Treatment with UV-C and Organic Acid to Reduce Aspergillus ochraceus and Rhodotorula mucilaginosa Contamination)

  • 이은선;김종희;김부민;오미화
    • 한국식품위생안전성학회지
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    • 제39권1호
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    • pp.54-60
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    • 2024
  • 본 연구는 축산물 생산 환경에서 오염 가능한 Aspergillus ochraceus와 Rhodotorula mucilaginosa를 저감하기 위하여 자외선과 유기산을 활용하여 그 효과를 구명하였다. 이를 위하여 각각의 균 현탁액(107-108 spores/mL)을 칼 표면에 1 mL 접종하고 37℃에 건조한 후 각각의 처리 조건에 활용하였다. 먼저 유기산 효과를 구명하기 위하여 아세트산, 젖산, 구연산을 활용하였으며 적정 농도 선정을 위하여 0.5, 1, 2, 3, 4, 5%의 농도로 제조하였다. 그 결과 아세트산의 경우 약 5 log, 젖산은 최대 2 log CFU/cm2 감소하였으나, 구연산의 경우 1 log 이하로 미미한 수준이었다. 이에 따라 유기산 처리 효과를 더욱 극대화하기 위해 자외선과의 복합처리를 진행하고자 하였다. 두 균주는 모든 유기산에서 90% 이상 감소하여 초기 균주와 비교하였을 때 유의적인 차이(P<0.05)를 보였으며 특히 4%의 젖산은 자외선(360 mJ/cm2)과 함께 처리하였을 때, 2 log CFU/cm2이상 감소하였으며 같은 조건에서 아세트산은 5 log CFU/cm2이상의 저감능을 보였다. 그러나 본 연구에서 사용한 4% 농도의 아세트산으로 제조할 경우 이취가 매우 심하여 작업자가 생산환경에서 사용하기에 어려움이 있다. 이에 따라서 현장에 적용하기 위한 유기산과 자외선 최적 처리 조건은 4% 젖산 용액에 1분간 침지한 후 자외선을 20분 가량(360 mJ/cm2) 살균 처리하는 방법으로 선정하였다. 최종적으로 유기산 세척 및 자외선 처리가 된 칼로 돼지고기 절단 작업을 수행하였을 때, 현장 오염 수준의 진균류 농도에서 작업 후 돼지고기 표면으로 이행되는 오염량은 모두 불검출 되었다. 본 연구를 통하여 실험실 규모뿐만 아니라 최종적으로 현장에서 살균된 도구를 활용하여 작업 시 고기 표면까지 이행되는 교차오염을 방지할 수 있는 것으로 사료된다.

촉진열화목재의 흡습성과 초음파전달속도 (Moisture Sorption and Ultrasonic Velocity of Artificially Weathered Sitka Spruce)

  • 강호양;박상진;김영숙
    • Journal of the Korean Wood Science and Technology
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    • 제30권1호
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    • pp.18-24
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    • 2002
  • 시트카스프루스 50×133×10 mm3 시편을 340 mm 제논광과 주기적 강우장치를 갖춘 장치 내에서 촉진열화 시켰다. 시편은 자외선만 조사하거나 자외선을 조사하면서 동시에 강우를 병행하였으며 처리시간도 10시간과 20시간으로 구분하였다. 촉진열화 처리재의 물리적 성질을 색도, 흡습성 그리고 초음파 전달속도를 측정하여 조사하였다. 자외선 조사시간이 길수록 표면 명도가 낮아졌다. 강우처리는 표면 명도의 감소를 촉진하였으며 흡습성을 증가시켰다. 자외선과 강우 병행 처리재 중에 10시간 처리재의 흡습성이 20시간 처리재보다 높았는데 이는 20시간 처리재의 표면이 과도하게 열화된 때문일 가능성이 있다. 촉진열화 처리재의 초음파 전달속도는 무처리재보다 높았는데 이는 촉진열화에 의해 목재의 탄성계수가 높아졌거나 밀도가 감소했다고 할 수 있다.

Determination of florfenicol residues in swine tissues using high-performance liquid chromatography with ultraviolet photometric detector

  • Chae, Won-Seok;Yoo, Chang-Yeul;Tutkun, Lutfiye;Kim, Suk;Lee, Hu-Jang
    • Journal of Preventive Veterinary Medicine
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    • 제42권4호
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    • pp.171-176
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    • 2018
  • A study of the tissue depletion of florfenicol (FFC) administered orally to pigs at a dose of 0.05 kg/ton feed for 7 days was performed. Sixteen healthy cross swine were administered with FFC. Four treated animals were arbitrarily selected to be sacrificed 1, 3 and 5 days after the end of treatment. FFC residue concentrations in muscle, liver, kidney, and fat were determined using high-performance liquid chromatography (HPLC) with ultraviolet photometric detector at 230 nm. The correlation coefficient ($R^2$) of the calibration curve for florfenicol amine (FFCa) was > 0.997 and the limits of detection and quantification were 0.012 and $0.040{\mu}g/mL$, respectively. Recovery rates in swine edible tissues ranged from 79.1 to 93.5%. In the FFC-treated group, FFC residues at 3 days post-treatment were below the maximum residue limits (MRLs) in muscle, kidney and fat, and those at 5 days post-administration were below the MRLs in all edible tissues. These results suggest that the withdrawal period of FFC after the drug treatment might be 5 days, which is a sufficient amount of time for reduction of the FFC residues below the MRLs in all edible tissues.

Ultraviolet-C와 플라즈마를 병합 처리하는 양산형 살균 시스템을 이용한 후춧가루 미생물 저해 (Microbial Decontamination of Black Pepper Powder Using a Commercial-scale Intervention System Combining Ultraviolet-C and Plasma Treatments)

  • 방인희;이승영;한균식;민세철
    • 산업식품공학
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    • 제22권4호
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    • pp.386-391
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    • 2018
  • 양산형 UV-P 처리는 장비를 20분 이상 작동하였을 때 후춧가루의 토착 중온 호기성 세균을 유의적으로 저해시켰다. UV-P 처리는 토착 미생물 저해에 있어 상승효과를 보여주었으나 후춧가루의 색을 어둡게 하였다. UV-P 처리의 후춧가루 미생물 저해 효과와 색 변화에 대한 영향은 처리되는 후춧가루를 오염시키는 미생물과 후춧가루 종류에 영향을 받음을 알 수 있었다. 또한 본 연구 결과는 UV-P 장비 내 플라즈마 충적 시간과 후춧가루의 $a_w$ 상승이 UV-P 처리된 후춧가루의 미생물 저해 효과 향상과 색 유지에 효과적이지 않음을 알 수 있었다. 본 연구는 UV-C와 플라즈마 처리를 병합한 양산형 UV-P 처리가 후춧가루의 토착 미생물을 저해시키는 기술로서의 가능성을 보여주었다. 그러나 앞으로 추가적인 연구를 통해 UV-P 처리부의 온도상승 및 후춧가루의 색도 변화를 최소화할 수 있는 방법이 제시되어야 할 것이다.

자외선으로 손상된 마우스 피부에 대한 라벤더 오일 효과 (Effect of Lavender Oil on the Ultraviolet-Damaged Mice Skin)

  • 이승자;심미자;김영철
    • Environmental Analysis Health and Toxicology
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    • 제23권4호
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    • pp.315-323
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    • 2008
  • In this study, the backs with a hair cut of 6-week-old healthy ICR male mice were once exposed to a dose of $400\;mJ/cm^2$ UVB. An acute dermal inflammation was observed, and the certified 100% pure and natural lavender essential oil were applied to the UVB-exposed mice skin twice a day. It was observed that the mice exposed to UVB resulted in an acute inflammation, and when treated with lavender oil the degree of inflammation was much alleviated, and the inflamed skins of both the control and lavender oil-treatment groups were cured almost completely after 6 days of the UVB exposure. At 24 hours after UVB exposure, the epidermal keratinocytes in the control group showed a cell-membrane damage with the destruction of intercellular junctions, agglutination of tonofilaments within the cytoplasm and nucleus damage, while the lavender oil-treatment group had much less cell damage than the control group. While the control group showed a significant increase (p<0.05) in the activity of XO up to 144 hours, the lavender oil-treatment group did not show any significant increase except for 48 hours after the UVB exposure. Both the control and lavender essential oil-treatment groups had a significant decrease in the activities of CAT and SOD up to 96 hours. Particularly, the CAT activity was significantly lower(p<0.05) in the lavender oil-treatment group than the control group up to 48 hours, and higher than the control group at and after 96 hours. The GST activity was significantly decreased in both the control and lavender oil-treatment groups up to 96 hours after the UVB exposure except for the control group at 24 hours, and that of the lavender oil-treatment group was higher than the control group at and after 96 hours. Therefore, it is assumed that the application of the lavender oil to the ultraviolet-damaged mice skin can be effective in treatment for the damaged skin.

이산화염소수와 Ultraviolet-C 병합 처리에 따른 레드 치커리와 청경채의 저장 중 품질에 미치는 영향 (Effect of Combined Treatment of Aqueous Chlorine Dioxide with Ultraviolet-C on the Quality of Red Chicory and Pak Choi during Storage)

  • 김현진;송현정;송경빈
    • 한국식품영양과학회지
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    • 제40권2호
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    • pp.245-252
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    • 2011
  • 신선 채소 중 레드 치커리와 청경채의 미생물학적 안전성 확보를 위해 50 ppm 이산화염소수와 10 kJ/$m^2$ UV-C 조사 병합 처리에 따른 저장 중 미생물 수 및 품질 변화에 미치는 영향을 처리 후 $4{\pm}1^{\circ}C$에서 7일 동안 저장하면서 실험하였다. 레드 치커리와 청경채의 총 호기성 세균 수는 대조구와 비교 시, 이산화염소수와 UV-C 병합 처리구에서 2.64, 2.55 log CFU/g 감소시켰으며, 효모 및 곰팡이는 2.41, 2.00 log CFU/g 감소시켰다. 또한, 레드 치커리와 청경채의 저장 7일 후, 이산화염소수와 UV-C 병합 처리구의 총 호기성 세균수는 3.71, 3.93 log CFU/g으로 대조구와 비교할 때, 2.60, 2.69 log CFU/g의 유의적인(p<0.05) 차이를 나타냈다. 병합 처리는 대조구와 비교하여 레드 치커리와 청경채의 저장 중 Hunter 색도 값에 부정적인 영향을 끼치지 않았다. 관능검사에 있어서도 병합 처리구가 대조구보다 저장 중 관능적 품질 유지에도 효과가 있는 것으로 나타났다. 따라서 본 연구결과, 50 ppm 이산화염소수와 10 kJ/$m^2$ UV-C 조사의 병합 처리가 레드 치커리와 청경채의 저장 중에 오염될 수 있는 위해미생물의 감소와 외관적 품질유지에 효과적인 처리 기술이라고 판단된다.

Photosynthetic Response and Protective Regulation To Ultraviolet-B Radiation In Green Pepper (Capsicum annuum L.)Leaves

  • Kim, Dae-Whan;Jun, Sung-Soo;Hong, Young-Nam
    • Journal of Photoscience
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    • 제8권1호
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    • pp.1-7
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    • 2001
  • The deteriorative effect of ultraviolet-B(UV-B) radiation on photosynthesis was assessed by the simultaneous measurement of O$_2$ evolution and chlorophyll(Chl) fluorescence in green pepper. UV-B was given at the intensity of 1 W$.$m$\^$-2/, a dosage often encountered in urban area of Seoul in Korea, to detached leaves. Both Pmax and quantum yield of O$_2$ evolution was rapidly decreased, in a parallel phase, with increasing time of UV-B treatment. Chl fluorescence parameters were also significantly affected. Fo was increased while both Fm and Fv were decreased. Photochemical efficiency of PSII(Fv/Fm) was also declined, although to a lesser extent than Pmax. Both qP and NPQ were decreased similarly with increasing time of UV-B treatment. However, PS I remained stable. The addition of lincomycin prior to UV-B treatment accelerated the decline in Fv/Fm to some extent, suggesting that D1 protein turnover may play a role in overcoming the harmful effect of UV-B. The amount of photosynthetic pigments was less affected than photosynthetic response in showing decline in Chl a and carotenoids after 24 h-treatment. Presumptive flavonoid contents, measured by changes in absorbance at 270 nm , 300 nm and 330nm, were all increased by roughly 50% after 8 h-treatment. Among antioxidant enzymes, activities of catalase and peroxidase were steadily increased until 12h of UV-B treatment whereas ascorbate perxidase, dehydroascorvate reductase and glutathione reductase did not show any significant change. The results indicate that deteriorative effect of UV-B on photosynthesis precedes the protection exerted by pigment synthesis and antioxidant enzymes.

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Peracetic Acid Treatment as an Effective Method to Protect Wood Discoloration by UV Light

  • PARK, Kyoung-Chan;KIM, Byeongho;PARK, Hanna;PARK, Se-Yeong
    • Journal of the Korean Wood Science and Technology
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    • 제50권4호
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    • pp.283-298
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    • 2022
  • Wood has always been used for various day-to-day applications such as interior or exterior construction materials, and household products. However, it can undergo photodegradation and discoloration by environmental factors including ultraviolet (UV) light, and thus has shortened its service life. Bleaching or delignification of wood surfaces is a suitable solution to stabilize wood against weathering by UV because these techniques can alter or remove the chromophores in lignin, which is a main factor of wood discoloration. To improve the color stability of wood surface according to the lifespan, surface delignification was conducted using peracetic acid (PAA) and hydrogen peroxide (HP) on the woods of Larix kaempferi and Quercus mongolica. After the PAA treatment, L* increased considerably from 60-70 to 90-95. Furthermore, wood surface color did not change significantly after UV exposure. The color differences (𝜟E*) between before and after PPA treatment of wood showed the 4.8-12.2 of L. kaempferi, and 1.7-3.7 of Q. mongolica, respectively. The lignin-related peaks in Fourier transform infrared spectroscopy (FT-IR) spectra disappeared with increased duration of PAA treatment. These results confirmed that the lignin component was partially or completely removed after the PAA treatment; the color differences (𝜟E*) clearly showed that there was a reduction in redness (a*) and yellowness (b*), and an increase in lightness (L*) owing to the removal of lignin. Based on these results, this study demonstrated that the partial removal of lignin from wood surfaces is a fundamental method for resolving photo-degradation.