• Journal of Microbiology and Biotechnology
• /
• 제19권9호
• /
• pp.932-945
• /
• 2009

Several species of Gram-positive bacteria have cell wall peptidoglycan (syn. murein) in which not all of the sugar moieties are N-acetylated. This has recently been shown to be a secondary effect, caused by the action of a peptidoglycan N-acetylglucosamine deacetylase. We have found that the opportunistic pathogen Listeria monocytogenes is unusual in having three enzymes with such activity, two of which remain in the cytoplasm. Here, we examine the enzyme (PgdA) that crosses the cytoplasmic membrane and is localized in the cell wall. We purified a hexa-His-tagged form of PgdA to study its activity and constructed a mutant devoid of functional Lmo0415 (PgdA) protein. L. monocytogenes PgdA protein exhibited peptidoglycan N-acetylglucosamine deacetylase activity with natural substrates (peptidoglycan) from both L. monocytogenes and Escherichia coli as well as the peptidoglycan sugar chain component N-acetylglucosamine, but not with N-acetylmuramic acid. As was reported recently [6], inactivation of the structural gene was not lethal for L. monocytogenes nor did it affect growth rate or morphology of the cells. However, the pgdA mutant was more prone to autolysis induced by such agents as Triton X-100 and EDTA, and is more susceptible to the cationic antimicrobial peptides (CAMP) lysozyme and mutanolysin, using either peptidoglycan muramidases or autolysis-inducing agents. The pgdA mutant was also slightly more susceptible than the wild-type strain to the action of certain beta-lactam antibiotics. Our results indicate that protein PgdA plays a protective physiological role for listerial cells.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2018년도 추계학술대회
• /
• pp.113-113
• /
• 2018

Endophthalmitis is a disease that causes ocular inflammation and has a catastrophic effect on eyesight. Recent studies show that Enterococcus faecalis is rapidly increasing causative bacterium of endophthalmitis. It is predicted that the increased endophthalmitis by E. faecalis is presumable due to the high resistance of E. faecalis to moxifloxacin (MFX), which is a common antibiotic used for eye drop. Because of the need for therapeutic agents to overcome this problem, this study sought to explore the feasibility of developing a combination therapy using Orostachys japonicus. The ethylacetate fraction of O. japonicus (OJA) used in this study. Antimicrobial activity was tested 13 E. faecalis strains including one E. faecalis standard strain, eight clinically isolated E. faecalis strains and four quinolone resistant E. faecalis strains using CLSI antibiotic susceptibility test method. Minimal Inhibitory Concentration (MIC) of OJA was confirmed to be $500{\mu}g/ml$ for all 13 strains. Then we tested for the synergistic effect of OJA to MFX using checkboard test method. The MIC of MFX was $0.25{\mu}g/ml$ for the standard strain and 8 for the clinical isolates, and $16{\sim}64{\mu}g/ml$ for the quinolone - resistant strains. When OJA was mixed with MFX, no synergistic effect was observed in all strains, but the antibacterial activity of OJA remained unchanged. Most ocular other strains can be removed by MFX except the MFX resistant E. faecalis, which can be removed by OJA in combination therapy. Therefore, OJA can be a potential candidate for the combined treatment endophthalmitis.

• 동아시아식생활학회지
• /
• 제19권2호
• /
• pp.202-209
• /
• 2009

This study was conducted to gather the basic data on the spread of the domestic kiwifruits, and the development of the manufactured goods and the health functional foods produced using kiwifruits. We determined the chemical compositions of four types of kiwifruits cultivated in Korea, Daeheung, Bidan, Haegeum and Hayward. In addition, we measured the anti-microbial activities and cytotoxicities of these types of kiwifruits. The vitamin C contents of the kiwifruits increased in the order of Bidan (93.82 mg/100 g), Daeheung (85.89 mg/100 g), Haegeum (83.73 mg/100 g) and Hayward (75.28 mg/100 g). The total amino acids contents per 100 g of kiwifruit (dry weight basis) were 483.97 mg (Haegeum), 453.08 mg (Hayward), 437.27 mg (Bidan) and 369.35 mg (Daeheung). The K and Ca contents of the kiwifruits ranged from 14.56~37.12 mg/L and 1.94~8.24 mg/L, respectively; however, the Fe, Mg, Zn and Cr contents all less than 1.83 mg/L. The antimicrobial activities of methanol extracts of kiwifruits against five gram positive bacteria at concentration of 2,000 mg/L in terms of inhibition diameter ranged from 8.8~12.8mm, while raged from 9.2~13.1mm against three gram negative strains of bacteria. The hyperplasia inhibition of lung cancer cells (Calus-6) by 800 mg/L kiwifruits extracts of Bidan, Haegeum, Daeheung and Hayward kiwifruits were 21.2%, 9.5%, 6.7% and 5.0%, respectively. Consequently, it was assumed that kiwifruits was rich in vitamin C, amino acids and K, and that they would therefore be useful in processed goods.

• 한국축산식품학회지
• /
• 제37권3호
• /
• pp.429-439
• /
• 2017

This study investigated the antioxidative and functional effects of a curing agent containing grapefruit seed extract (GSE) on the quality and storage characteristics of chicken breast. The total polyphenol and total flavonoid contents of GSE were 45.06 mg/g and 36.06 mg/g, respectively. The $IC_{50}$ value of 2,2-diphenyl-1-picrylhydrazyl hydroxyl scavenging of GSE was $333.33{\mu}g/mL$. The chicken breast comprised six groups: no-treatment (N), 0.2% ascorbic acid + 70 ppm sodium nitrite (C), 0.05% GSE (G0.05), 0.1% GSE (G0.1), 0.3% GSE (G0.3), and 0.5% GSE (G0.5). The pH and cooking loss of cured chicken breast decreased with increasing GSE levels, and the water holding capacity increased with increasing GSE levels. The hardness and chewiness of GSE-treated chicken breast were higher than those of N and C. Hunter's L and a color values increased significantly after GSE addition. Moreover, 0.1% GSE (G0.1) increased the flavor and total acceptability scores. The 2-thiobarbituric acid and volatile basic nitrogen values of the 0.5% GSE group decreased significantly compared with those of C group. Total microbial counts of GSE-treated chicken breast were higher than those of C, but that lower than those of N. Adding GSE to chicken breast delayed lipid peroxidation and had antimicrobial effects during cold storage. GSE improved shelf life and palatability; therefore, it could be used as a natural antioxidant and functional curing agent ingredient in meat products.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권17호
• /
• pp.7641-7651
• /
• 2015

It has been shown previously that nutritional supplements rich in polyphenolic compounds play a significant role in prostate cancer chemoprevention. Propolis is a natural, resinous hive product that has several pharmacological activities including antimicrobial, antioxidant, anti-inflammatory, and antitumoral activities. The aim of this study was to compare the cytotoxic, antioxidant and antitumoral activities of an ethanolic extract of Egyptian propolis (EEP) in vitro with an established chemotherapeutic drug such as doxorubicin (DOX), and the effects of their combination against the PC3 human prostate cancer cell line. Cellular viability and $IC_{50}$ levels with EEP, DOX and their (v/v) combination were detected by sulphorhodamine-B (SRB) assay after incubation of PC3 cells for 72h with different doses (0, 0.01, 0.1, 1, 10 and $100{\mu}g/ml$). Two selected doses of $IC_{50}$ and $IC_{25}$ were applied to cells for 24h for antitumor evaluation assay of treatment compounds. EEP and its (v/v) combination with DOX showed significant antitumor potential besides high antioxidant properties of superoxide dismutase (SOD), total antioxidant capacity (TAC), catalase (CAT), nitric oxide (NO) and reduced glutathione (GSH) levels when compared with the control untreated cells. DNA fragmentation assay and semi quantitative RT-PCR analyses for p53 and Bax genes showed that EEP activated cellular apoptosis and increased the mRNA expression levels more than other treatment. In conclusion, EEP alone or in combination with DOX at both doses used here showed greater antioxidant, antiproliferative and apoptotic effects against the PC3 cell lines as compared to treatment with DOX alone. Therefore, EEP could be considered as a promising candidate for prostate cancer chemotherapy.

• 한국자원식물학회지
• /
• 제30권5호
• /
• pp.535-541
• /
• 2017

본 연구에서는 카카오 추출물의 알칼로이드계 성분의 함량을 관찰하고 항산화, 항균, 항염증 활성을 확인하였다. CAEt, CAMe추출물 함유 Gel을 제조하여 물리적 안정성을 관찰하였다. 카카오 추출물의 생리활성을 관찰하기 위해 DPPH, SOD 측정을 진행하였으며 세포독성 및 LPS로 유발시킨 일산화질소의 소거능에 대한 연구를 진행하였다. 또한 알칼로이드계 퓨린 구조를 가진 카카오 추출물을 첨가시킨 Gel을 제조하여 60일 동안 상온에서의 안정성을 평가하였다. 카카오 추출물의 항산화 활성 검증에서는 CAEt 추출물에서 $IC_{50}$ 값은 $43.14{\mu}g/m{\ell}$, CAMe 추출물의 $IC_{50}$ 값은 $35.42{\mu}g/m{\ell}$로 관찰되었다. SOD 측정에서도 CAEt 추출물에서 $IC_{50}$ 값은 $90.9{\mu}g/m{\ell}$, CAMe 추출물의 $IC_{50}$ 값은 $52.6{\mu}g/m{\ell}$로 관찰되었다. MeOH 조건에서 추출한 CAMe 추출물의 항산화능이 높은 것을 알 수 있었다. 추출물 3%가 함유된 gel (CAEt-Gel, CAMe-Gel)을 제조하였다. 항균활성 측정 결과 CAMe 추출물이 함유된 gel 제형이 더 높은 항균성을 나타내는 것을 확인하였다. MTT assay로 관찰한 세포독성은 80%이상의 세포 생존율을 보였으며, LPS로 활성화된 Raw 264.7 세포에서 NO 발생을 관찰한 결과 CAMe-Gel을 처리한 군에서 NO 생성량이 유의하게 억제되는 것을 확인할 수 있었다. 본 연구에서는 위와 같은 결과를 근거로 카카오 추출물의 알칼로이드계 성분을 인체내에 적용하기 위해 제조한 Gel은 화장품 및 의료용 소재로 다양한 활용이 가능할 것으로 사료된다.

• 한국약용작물학회지
• /
• 제21권2호
• /
• pp.136-141
• /
• 2013

Chelidonium majus (CM) contains several isoquinoline alkaloids that have been reported to have various biological activities such as anti-inflammatory, antimicrobial, antioxidant, immune-modulatory, and antitumoral. It has been reported that the extract of CM had an antioxidant potential, however the mechanism has not been verified. In this study, we found that CM extract activated FOXO3a. FOXO3a is a transcription factor that involved in various biological processes such as cell cycle arrest, apoptosis, DNA repair, and ROS detoxification. Transcriptional activities of FOXO3a were regulated by post-translational modifications including phosphorylation, acetylation, and ubiquitination. Protein level of FOXO3a was increased by CM extract. Promoter activities of FOXO-transcriptional target genes such as MnSOD, p27 and GADD45 were activated by CM extract in a dose dependent manner. In addition, protein level of MnSOD, major antioxidant enzyme, was increased by CM extract. Thereby ROS level was decreased by CM in old HEF cells. These results suggest that CM extract has an antioxidant activity through FOXO activation.

• 생약학회지
• /
• 제43권4호
• /
• pp.323-327
• /
• 2012

Acne, also known as Acne vulgaris, is a common disorder of human skin involving the sebaceous gland and Propionibacterium acnes (P. acnes). The purpose of this study was to demonstrate whether anti-acne herbal complex (AAHC), a functional extract from herbal complex can be used for acne treatment as a natural product. We first demonstrated anti-acne activity of AAHC in mouse acne model. Acne was induced by injecting P. acnes on the backside $2{\times}10^7$ CFUs in ICR mice and then the mice were treated with AAHC by dermal application once daily. ACFREE$^{(R)}$ (clindamicin phosphate) was used as a positive control. Treatment with AAHC decreased the P. acnes-induced skin swelling and inflammation. AAHC treatment significantly decreased serum DHT concentration in acne-induced mice. Especially, treatment of 20% AACH in mice was more effected than 40%. We next evaluated the antimicrobial property of AAHC against P. acnes, Staphylcococcus aureus (S.aureus), and Escherichia coli (E. coli). Incubation of P. acnes, S. aureus, and E. coli with AAHC showed minimal inhibitory concentration (MIC) values against the bacterial growth lower. Alamar blue method was also carried for the antibacterial activity. It was effectively MIC level at 6.25% of P. acnes. AAHC effectively inhibited the growth of S. aureus and E. coli at 0.097% on MIC level, respectively. Our results showed the potential of using AAHC as an alternative treatment for antibiotic therapy of acne and the application of AAHC as a herbal medicine for acne treatment.

• 한국동물위생학회지
• /
• 제38권1호
• /
• pp.25-30
• /
• 2015

Bee venom has been used as to prevent and treat bovine mastitis as natural antimicrobial compounds in some dairy cattle farms in Korea. It is needed to determine the residual of bee venom in milks of dairy cattle treated with bee venom. Since bee venom is not approved as a raw material for animal drugs, the preprocessing method to detect bee venom residual in milk and the tolerance limit for its residue has not been established yet in Korea. Therefore, the purpose of this study was to develop pre-processing method not affecting major component of bee venom for detection of its residue in milks using ultra-high performance liauid chromatography (UHPLC). In addition, bee venom residue was also analyzed in milk samples of dairy cattle treated for mastitis with bee venom using UHPLC with the developed pre-processing method in this study. As a result, melittin, histamin and phospolipase A2, the major components of bee venom, were all detected by UHPLC with the pre-processing method developed in this study. The results of this study suggest that the pre-processing method developed in this study can be useful to detect bee venom residue in dairy cattle milk. We also found that no bee venom residues were detected in milk samples collected from dairy cattle treated with bee venom after 1 and 3 days, respectively.

• 한국동물위생학회지
• /
• 제39권3호
• /
• pp.159-166
• /
• 2016

Clostridium perfringens, Salmonella thyphimurium and S. Montevideo isolated from the intestines of dead broiler chickens in Korea were tested for antibacterial effects to purifed bee venom. Purified bee venom from Apis mellifera L. has been used as natural antimicrobial compounds in pigs, cows, dairy cattle and chicken farms in Korea. To investigate antibacterial effect of purified bee venom was evaluated by agar well diffusion method, minimum inhibitory concentraion (MIC), minimum bactericidal concentration (MBC), and postantibiotic effect (PAE). Purified bee venom exhibited significant inhibition of bacterial growth of C. perfringens, S. thyphimurium and S. Montevideo with MIC value of 0.85, 0.68 and $0.69{\mu}g/mL$, respectively. The MBC value of purified bee venom against C. perfringens, S. thyphimurium and S. Montevideo were 3.33, 2.66 and $2.86{\mu}g/mL$. Furthermore, the results of PAE values against C. perfringens, S. thyphimurium and S. Montevideo showed the bacterial effect with 3.5, 4.0 and 3.5 hr. Stability of pufifed bee venom at acidity from pH 1 to pH 8 for 24 hr was the antibacterial activity for C. perfringens, S. thyphimurium and S. Montevideo and melittin contents. Also purified bee venom processed through the heating for 15 min, there was no signification loss of the antibacterial activity and melittin at below $100^{\circ}C$. These results obtained in this study suggest that purified bee venom might be utilized as a feed additive in poultry diets.