• Journal of Food Hygiene and Safety
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• v.39 no.1
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• pp.35-43
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• 2024

Numerous methods have been applied to assess the antibacterial effectiveness of hand hygiene products. However, the different results obtained through various evaluation methods have complicated our understanding of the real efficacy of the products. Few studies have compared test methods for assessing the efficacy of hand hygiene products. In particular, reports on ex vivo pig skin testing are limited. This study aimed to compare and characterize the methodologies applied for evaluating hand hygiene products, involving in vitro, ex vivo, and in vivo approaches, applicable to both leave-on sanitizers and wash-off products. Our further aim was to enhance the reliability of ex vivo test protocols by identifying influential factors. We performed an in vitro method (EN1276) and an in vivo test (EN1499 and ASTM2755) with at least 20 participants, against Serratia marcescens or Escherichia coli and Staphylococcus aureus. For the ex vivo experiment, we used pig skin squares prepared in the same way as those used in the in vivo test method and determined the optimal treated sample volumes for sanitizers and the amount of water required to wash off the product. The hand sanitizers showed at least a 5-log reduction in bacterial load in the in vitro test, while they showed little antibacterial activity in the in vivo and ex vivo tests, particularly those with a low alcohol content. For the hand wash products, the in vitro test was limited because of bubble formation or the high viscosity of the products and it showed low antibacterial activity of less than a 1-log reduction against E. coli. In contrast, significantly higher log reductions were observed in ex vivo and in vivo tests, consistently demonstrating these results across the two methods. Our findings revealed that the ex vivo and in vivo tests reflect the two different antibacterial mechanisms of leave-on and wash-off products. Our proposed optimized ex vivo test was more rapid and more precise than the in vitro test to evaluate antibacterial results.

• Journal of Biomedical Engineering Research
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• v.40 no.5
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• pp.143-150
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• 2019

To evaluate the toxicity of ophthalmic drug, the Draize test and Bovine Corneal Opacity and Permeability (BCOP) test commonly used. In Draize test, experimental animals were under stress and pain due to long-term exposure of drug. In addition, regarding physiological functions, animal model is not perfectly reflected a human eye condition. Although some models such as $EpiOcular^{TM}$, HCE model, LabCyte Cornea-Model, and MCTT $HCE^{TM}$ were already presented advanced cornea ex-vivo model to replace animal test. In this sense, cornea tissue structure mimicked ex-vivo toxicity model was fabricated in this study. The corneal epithelial cells (CECs) and keratocytes (CKs) isolated from rabbit eyeball were seeded on non-patterned silk film (n-pSF) and patterned silk film (pSF) at $32,500cells/cm^2$ and $6,500cells/cm^2$. Sequentially, n-pSF and pSF were stacked to mimic a multi-layered stroma structure. The thickness of films was about $15.63{\mu}m$ and the distance of patterns was about $3{\mu}m$. H&E stain was performed to confirm the cell proliferation on silk film. F-actin of CKs was also stained with Phalloidin to observe the cytoskeletal alignment along with patterns of the pSF. In the results, CECs and CKs were shown the good cell attachment on the n-pSF and pSFs. Proliferated cells expressed the specific phenotype of cornea epithelium and stroma. In conclusion, we successfully established the ex-vivo cornea toxicity model to replace the eye irritation tests. In further study, we will set up the human ex-vivo cornea toxicity model and then will evaluate the drug screening efficacy.

• Journal of Nutrition and Health
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• v.49 no.5
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• pp.277-287
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• 2016

Purpose: This study was performed to compare total phenolic contents, in vitro antioxidant capacity, and reduction effect of Korean food groups on ex vivo DNA damage in human cells and analyze correlations between each indicator. Methods: Vegetable foods in the Korean diet based the results of the KNHANES V-2 (2011) were classified into 10 food groups: cereals, fruits, vegetables, nuts, kimchi, seaweeds, potatoes, mushrooms, legumes, and oils. Eighty-four foods constituted more than 1% of the total intake in each food group and finally designated as vegetable foods in the Korean diet. Total phenolic content of each food group was measured. Further, in vitro antioxidant capacity was measured based on DPPH radical scavenging assay, TEAC assay, and $ORAC_{ROO{\cdot}}$ assay. Ex vivo DNA damage in human lymphocytes was assessed using comet assay. Results: Total phenolic contents of food groups of the Korean diet increased in the order of mushrooms, fruits, vegetables, seaweeds, and kimchi. Meanwhile, antioxidant rankings of food groups as mean values from the three in vitro test methods increased in the order of mushrooms, seaweeds, vegetables, kimchi, and fruits. Protection against ex vivo DNA damage in human lymphocytes was highest in mushrooms, followed by vegetables, fruits, seaweeds, and kimchi. The rankings of the food groups for total phenolic content, in vitro DAC, and ex vivo DNA protection activity were similar, and correlations between each indicator were significantly high. Conclusion: Mushrooms, fruits, vegetables, and seaweeds among the tested food groups in the Korean diet showed high total phenolic contents, in vitro antioxidant capacities, and protection against DNA damage. Correlations between each indicator in terms of total phenolic content, in vitro antioxidant capacity, and ex vivo DNA protection between each food group were found to be particularly high.

• Journal of Pharmaceutical Investigation
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• v.35 no.2
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• pp.71-74
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• 2005

The aim of this study was to analyze characteristics of the barrier function of excised porcine buccal mucosa to the test compounds, estradiol, propranolol HCI, melatonin, and mannitol with a wide range of partition coefficient values. The permeability of melatonin was measured through frozen, stored, and fresh porcine buccal mucosa to examine the impact of storage conditions on the permeability of porcine buccal mucosa. The results demonstrated that the ex vivo permeability of the porcine buccal mucosa was greater for more lipophilic solutes, which was consistent with a series of molecules transported by passive transepithelial diffusion. The melatonin permeation profiles through frozen, stored, and fresh mucosa illustrated that damage was incurred by the freezing process of the mucosal tissue, leading to loss of the barrier function and thereby an increased permeation coefficient. It can be observed that the influence of compound lipophilicity on the association of the compounds with buccal mucosa was clear. The relationship between permeation coefficient and Log P values for the four compounds investigated demonstrated a proportional relationship, further confirming the importance of the lipophilicity of a compound to permeate the buccal mucosa. These results showed that the ex vivo porcine buccal mucosa model is a suitable tool to screen oral mucosal permeability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.543-548
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• 2000

EC-2B와 EC-2C 획분은 정향(Eugenia caryophyllata)의 알칼리 추출물로부터 에탄올 침전, cetavlon 처리 및 한외여과를 거쳐 분획하였다. EC-2B 획분은 APTT에서 항응고 활성을 가지는 반면, EC-2C 획분은 APTT와 TT 모두에서 항응고 활성을 가지고 있으며 EC-2B와 EC-2C에서 모두 혈소판 응집억제능을 관찰할 수 있었다. EC-2B와 EC-2C 획분의 경구투여에서 두 획분 모두 독성이 없었으며 EC-2B 획문은 1,000 mg/kg (mouse, intravenours)에서도 독성이 없었으나, EC-2C 획분은 LD50 322 mg/kg 정도의 독성을 가지고 있었다. 두 획분의 in vivo 성에서의 항응고 활성을 60% 생존율을 갖는 dose로 표시한 결과 EC-2B는 131 mg/kgdlsep 비해 EC-2C는 58 mg/kg로 활성의 차이가 in vitro에서 보다 크게 나타났다. 이 두획분을 sulfation시킨 후 활성의 변화를 ex vivo를 통해 확인한 결과 두 획분 모두 활성이 증가하였으며 특히 EC-2B 획분의 활성이 급격히 증가하였다.

• Journal of Nutrition and Health
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• v.50 no.1
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• pp.1-9
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• 2017

Purpose: Fruit and vegetable juices are known to be rich sources of antioxidants, which have beneficial effects on diseases caused by oxidative stress. The purpose of this study was to directly compare the antioxidant activities of fruit and vegetable juices marketed in Korea. Methods: We analyzed four fruit juices, two vegetable juices, two yellow-green juices, and six mixed vegetable juices. Antioxidant activities were analyzed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) test, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonate) (ABTS) test, and oxygen radical absorbance capacity (ORAC) assay. Protective effects against DNA damage were determined using an ex vivo comet assay with human lymphocytes. Results: DPPH radical scavenging activities were in the following order: blueberry juice > mixed vegetable C juice > kale juice > mixed vegetable P juice > grape juice. ABTS radical scavenging activities were in the following order: blueberry juice > mixed vegetable C juice > grape juice > mixed vegetable P juice > kale juice. Peroxyl radical scavenging activities as assessed by ORAC assay were in the following order: blueberry juice > kale juice > mixed vegetable C juice > grape juice. Grape or blueberry juice showed strong abilities to prevent DNA damage in lymphocytes, and the difference between them was not significant according to the GSTM1/GSTT1 genotype. Conclusion: Antioxidant activities of fruit and vegetable juices and ex vivo DNA protective activity increased in the order of blueberry juice, grape juice, and kale juice, although the rankings were slightly different. Therefore, these juices rich in polyphenols and flavonoids deserve more attention for their high antioxidant capacity.

• Journal of Food Hygiene and Safety
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• v.38 no.1
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• pp.1-11
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• 2023

Skin sanitizers are effective in killing or removing pathogenic microbial contaminants from the skin of food handlers, and the progressive growth of consumer interest in personal hygiene tends to drive product diversification. This review covers the advances in the application of efficacy tests for hand sanitizers to suggest future perspectives to establish an assessment system that is optimized to each product type (gel, liquid, and wipes). Previous research on the in vivo simulative test of actual consumer use has adopted diverse experimental conditions regardless of the product type. This highlights the importance of establishing optimal test protocols specialized for the compositional characteristics of sanitizers through the comparative analysis of test methods. Although the operational conditions of the mechanical actions associated with wiping can affect the efficacy of the removal and/or the inactivation of target microorganisms from the skin's surface, currently there is a lack of standardized use patterns for the exposure of hand sanitizing wipes to skin. Thus, major determinants affecting the results from each step of the overall assessment procedures [pre-treatment - exposure of sanitizers - microbial recovery] should be identified to modify current protocols and develop novel test methods. The ex vivo test, designed to overcome the limited reproducibility of in vivo human trials, is also expected to replicate the environment for the contact of sanitizers targeting skin microorganisms. Recent progress in the area of skin microbiome research revealed distinct microbial characteristics and distribution patterns after the application of sanitizers on hands to establish the test methods with the perspectives on the antimicrobial effects at the community level. The future perspectives presented in this study on the improvement of efficacy test methods for hand sanitizers can also contribute to public health and food safety through the commercialization of effective sanitizer products.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.420-427
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• 2011

The use of lactic-acid bacteria (LAB) is effective for preventing and curing immune disorders by activating the immune system in the digestive tract and the consequent immune response in the blood. In this study, LAB and mixed LABs were used in an atopic dermatitis (AD) mouse model. Alleviation of AD was observed based on the change in cytokine level and immunohistochemical staining. An ex vivo test showed that immunoglobulin-E and interleukin (IL)-4 levels were significantly lower in all groups treated with LAB than in the group treated with only 1-chloro-2,4-dinitrobenzene. Results of an in vivo test based on the ex vivo results showed that the scratch score decreased in all groups treated with the LAB and particularly decreased in the group treated with mixed LABs. Additionally, the T helper (Th) 1 cytokines interferon-gamma and IL-12p40 were upregulated by the LAB and mixed-LABs, whereas levels of the Th2 cytokine IL-4 were downregulated in a mouse model of AD-like skin lesions. Furthermore, hematoxylin & eosin and immunohistochemical staining of the dorsal area of the mice in each group showed that AD improved in the LAB-treated groups. These results suggest that LAB and mixed LABs inhibit the development of AD in NC/Nga mice by suppressing the Th2 cell response and increasing the Th1 cell response. Our results indicate that mixed LABs are better than LAB for treating AD-like skin lesions.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.123-123
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• 1993

Acetylsalicylic acid (aspirin)와 인삼의 항산화 성분인 maltol의 축합반응으로 합성된 신물질 Aspalatene이 저용량: 장기 복용시 항산화활성과 더불어 지혈시간 연장효과가 탁월함을 보고 한 바 있다. Aspalatone은 aspirin과는 달리, 장기 복용시에도 위궤양 유발 작용이 거의 나타나지 않으므로 말초순환개선제로서의 개발이 기대된다. 본 연구에서는 Aspalatone의 항혈전작용을 in vivo, ex vivo 및 in vitro에서 연구하였다. Mouse thromboembolism test를 이용한 in vivo실험에서 Aspalatone은 aspirin과 유사하게 collagen에 의한 치사를 유의적으로 감소시켰으며 ADP에 의한 치사에는 영향을 미치지 않았다. 또한 10일간의 장기 투여 실험에서는 저용량에서 영향을 미치지 않았다. 또한 10일간의 장기 투여 실험에서는 저용량에서 항혈전 작용을 나타내며 투여 중단 4일 후에도 약효가 유지되는 것을 밝혔다. 이는 Aspalatone이 aspirin과 같이 cycloosygenase에 작용하여 항혈전 작용을 나타냄을 강력히 시사하고 있다.

• CELLMED
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• v.2 no.2
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• pp.19.1-19.6
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• 2012

$Capparis$ $zeylanica$ Linn. a 'Rasayana' drug is used for its memory enhancing effects in the traditional Ayurvedic system of medicine. The aim of this study was to evaluate acetylcholinesterase (AChE) inhibitory and memory enhancing activities of $Capparis$ $zeylanica$ Linn. The$in-vitro$ and $ex-vivo$ models of AChE inhibitory activity were used along with Morris water maze test to study the effect on memory in rats. The anticholinesterase effect of methanolic and aqueous extracts of $Capparis$ $zeylanica$ was measured by spectrophotometric Ellman method at 0.1, 0.3, 1.0, 3.0, 10 and 30 mg/ml and brain monoamine oxidase (MAO-A and MAO-B) activity was assessed by Naoi's method. The results $in-vitro$ and $ex-vivo$ AChE assay revealed that methanolic and aqueous extracts of $Capparis$ $zeylanica$ inhibit AChE activity, whereas these extracts did not alter MAO activity at any concentration tested as compared to moclobemide and L-deprenyl. The results indicate that $Capparis$ $zeylanica$ improves scopolamine-induced memory deficits through inhibition of AChE activity, and not by direct MAO inhibition.