• Restorative Dentistry and Endodontics
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• 제44권1호
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• pp.8.1-8.7
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• 2019

Objectives: Irrigants are imperative in endodontic therapy for the elimination of pathogens from the infected root canal. The present study compared the antimicrobial efficacy of octenidine dihydrochloride (OCT) with chlorhexidine (CHX) and sodium hypochlorite (NaOCl) against Staphylococcus epidermidis (S. epidermidis) for root canal disinfection. Materials and Methods: The minimum inhibitory concentration (MIC) was obtained using serial dilution method. The agar diffusion method was then used to determine the zones of inhibition for each irrigant. Lastly, forty 6-mm dentin blocks were prepared from human mandibular premolars and inoculated with S. epidermidis. Samples were randomly divided into 4 groups of 10 blocks and irrigated for 3 minutes with saline (control), 2% CHX, 3% NaOCl, or 0.1% OCT. Dentin samples were then collected immediately for microbial analysis, including an analysis of colony-forming units (CFUs). Results: The MICs of each tested irrigant were 0.05% for CHX, 0.25% for NaOCl, and 0.0125% for OCT. All tested irrigants showed concentration-dependent increase in zones of inhibition, and 3% NaOCl showed the largest zone of inhibition amongst all tested irrigants (p < 0.05). There were no significant differences among the CFU measurements of 2% CHX, 3% NaOCl, and 0.1% OCT showing complete elimination of S. epidermidis in all samples. Conclusions: This study showed that OCT was comparable to or even more effective than CHX and NaOCl, demonstrating antimicrobial activity at low concentrations against S. epidermidis.

• 한국환경과학회지
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• 제28권2호
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• pp.225-233
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• 2019

In this study, we investigated the in vitro anti-biofilm activities of plant extracts of chives (Allium tuberosum), garlic (Allium sativum), and radish (Raphanus sativus L.) against environment harmful bacteria (gram-positive Staphylococcus aureus and, gram-negative Salmonella typhimurium and Escherichia coli O157:H7). In the paper disc assay, garlic extracts exhibited the highest anti-biofilm activity. The Minimal Inhibitory Concentration (MIC) of all plant extracts was generally higher for gram-negative bacteria than it was for gram-positive bacteria. Gram-negative bacteria were more resistant to plant extracts. The tetrazolium dye (XTT) assay revealed that, each plant extract exhibited a different anti-biofilm activity at the MIC value depending on the pathogen involved. Among the plant extracts tested, garlic extracts (fresh juice and powder) effectively reduced the metabolic activity of the cells of food-poisoning bacteria in biofilms. These anti-biofilm activities were consistent with the results obtained through light microscopic observation. Though the garlic extract reduced biofilm formation for all pathogens tested, to elucidate whether this reduction was due to antimicrobial effects or anti-biofilm effects, we counted the colony forming units of pathogens in the presence of the garlic extract and a control antimicrobial drug. The garlic extract inhibited the E. coli O157:H7 biofilm effectively compared to the control antimicrobial drug ciprofloxacin; however, it did not inhibit S. aureus biofilm significantly compared to ciprofloxacin. In conclusion, garlic extracts could be used as natural food preservatives to prevent the growth of foodborne pathogens and elongater the shelf life of processed foods.

• 한국약용작물학회지
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• 제16권5호
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• pp.320-325
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• 2008

치콘 및 엽채류의 저장기간 연장을 위해 천연보존제 및 천연항균제 선정을 위한 항균실험을 실시하고 후박 추출물이 미생물 최소 저해 농도 및 집락 형성 저해능이 높음을 확인하였다. 이를 엽채류에 도포함으로써 이들의 저장기간을 연장시키고자 수용성 추출물의 활용성을 극대화 할 수 있는 식용 나노입자를 제조하고 전자현미경 관찰 및 image anlyzer 측정을 통해 후박 추출물 나노입자의 80% 이상이 300nm 이하 크기로 형성되었음을 확인하였다. 투과전자현미경을 이용한 관찰을 통해서도 수십 nm $\sim$ 약 500nm 범위의 유사 구형 나노입자임을 확인하였으며, 엽채류 저장기간 연장 효과를 알아보고자 이 나노입자를 치콘 표면에 분무 도포하였다. 전자현미경을 통한 치콘 표면 촬영으로 도포된 후박 추출물 나노입자가 표면에 잔류하고 있음을 확인하였으며, HPLC 분석을 통해 후박 추출물을 서서히 방출하고 있음을 확인하였다. 나노입자를 도포한 치콘과 무처리 대조군의 저장기간에 따른 에틸렌 발생량을 GC로 측정한 결과, 입자를 도포한 치콘에서 초기 에틸렌 발생량이 높으나 저장기간에 따른 에틸렌 생성량의 증가를 억제해 7일 이후에는 발생량 자체도 적어졌음을 확인할 수 있었다. 이는 후박 추출물의 나노입자가 치콘의 세포호흡을 효과적으로 억제하는 것을 확인한 것으로 나노입자의 처리를 통해 저장기간의 연장효과를 나타내었다.

• 한국식품과학회지
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• 제48권5호
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• pp.445-453
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• 2016

젖산세균을 이용한 사과 발효 음료는 건강 증진을 위한 기능성 식품으로 이용할 수 있다. 이에 따라 본 연구에서는 젖산세균을 선발하여 발효 음료 제조를 시도하였다. 국내 전통 발효 식품에서 분리된 84종의 젖산세균 가운데 사과 음료에서 생육이 가장 우수하고 항당뇨 활성이 우수한 JBE245 균주를 최종 선발하였다. 메주에서 분리된 JBE245 균주는 Lactobacillus plantarum으로 동정되었으며 사과 발효 음료의 생균수는 24시간 배양 후 $3.6{\times}10^8CFU/mL$로 이후 생균수를 유지하였다. 항당뇨 활성의 지표인 알파 글루코시데이스 저해능은 발효전 18.5%에서 증가하여 최대 40.4%까지 증가하였다. 산화방지 활성 지표인 총 폴리페놀 함량은 583.6 mg GAE/mL로 발효 전(424.5 mg GAE/mL)보다 증가하였으며, DPPH 소거활성은 52.0%로 발효 전(43.5%) 보다 높았다. 발효 음료의 기호도를 조사한 결과, 발효 전후 모든 항목에서 유의적 차이는 없었으며 종합적 선호도는 각각 4.72, 4.22로 나타났다(p<0.05). 이러한 결과들을 토대로 JBE245 균주를 이용한 발효 음료가 산화방지 및 항당뇨 기능이 향상된 프로바이오틱 발효 식품이라는 점에서 유용할 것으로 보인다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권4호
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• pp.281-286
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• 2009

Introduction: Enamel matrix derivative (EMD) is a protein which is secreted by Hertwig root sheath and plays a major role in the formation of cementum and attachment of peridontium. Several studies have shown that EMD promoted the proliferation and differentiation of preosteoblasts, osteoblasts and periodontal ligament cells in vitro: however, reports showing the inhibition of osteogenic differentiation by EMD also existed. This study was designed to simultaneously evaluate the effect of EMD on the two cell lines (human mesenchymal stem cells: hMSC, human periodontal ligament derived fibroblasts: hPDLCs) by means of quantitative analysis of some bone related matrices (Alkaline phosphatase : ALP, osteopontin ; OPN, osteocalcin ; OC). Materials and Methods: hMSCs and hPDLCs were expanded and cells in the 4${\sim}$6 passages were adopted to use. hMSc and hPDLCs were cultured during 1,2,7, and 14 days with 0, 50 and 100 ${\mu}g/ml$ of EMD, respectively. ALP activity was assessed by SensoLyte ALP kit and expressed as values of the relative optical density. Among the matrix proteins of the bony tissue, OC and OPN were assessed and quantification of these proteins was evaluated by means of human OC immunoassay kit and human OPN assay kit, respectively. Results: ALP activity maintained without EMD at $1,2^{nd}$ day. The activity increased at $7^{th}$ day but decreased at $14^{th}$ day. EMD increased the activity at $14^{th}$ day in the hPDLCs culture. In the hMSCs, rapid decrease was noted in $7^{th}$ and $14^{th}$ days without regard to EMD concentrations. Regarding the OPN synthesis in hPDLCs, marked decrease of OPN was noted after EMD application. Gradual decrease tendency of OPN was shown over time. In hMSCs, marked decrease of OPN was also noted after EMD application. Overall concentration of OPN was relatively consistent over time than that in hPDLCs. Regarding the OC synthesis, in both of hPDLCs and hMSCs, inhibition of OC formation was noted after EMD application in the early stages but EMD exerted minimal effect at the later stages. Conclusion: In this experimental condition, EMD seemed to play an inhibitory role during the differentiation of hMSCs and hPDLCs in the context of OC and OPN formation. In the periodontium, there are many kinds of cells contributing to the regeneration of oral tissue. EMD enhanced ALP activity in hPDLCs rather than in hMSCs and this may imply that EMD has a positive effect on the differentiation of cementoblasts compared with the effect on hMSCs. The result of our research was consistent with recent studies in which the authors showed the inhibitory effect of EMD in terms of the differentiation of mineral colony forming cells in vitro. This in vitro study may not stand for all the charateristics of EMD; thus, further studies involving many other bone matrices and cellular attachment will be necessary.