scholarly journals Comparison of Antivirulence Activities of Black Ginseng against Methicillin-Resistant Staphylococcus aureus According to the Number of Repeated Steaming and Drying Cycles

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 617
Author(s):  
Young-Seob Lee ◽  
Kwan-Woo Kim ◽  
Dahye Yoon ◽  
Geum-Soog Kim ◽  
Dong-Yeul Kwon ◽  
...  

Korean ginseng has been widely used in Eastern medicine for thousands of years. The contents of the compounds in ginseng roots change depending on the amount of steaming and drying, and the drying method used. Black ginseng (BG) is the Korean ginseng processed by repeated steaming and drying. In this study, 5-year-old fresh Korean ginseng roots were steamed and dried 3 or 5 times, and we investigated how many cycles of steaming and drying are preferable for antivirulence activities against methicillin-resistant Staphylococcus aureus (MRSA). As a result, the antivirulence activities was increased by the treatment of BG that was steamed and dried three times, and the effect was further increased by five-time processed BG. Moreover, an ELISA showed that the TNF-α production of RAW264.7 cells stimulated by MRSA supernatants was inhibited by subinhibitory concentrations of BG extract. The expression of Hla, staphylococcal enterotoxin A (SEA), and staphylococcal enterotoxin B (SEB), an important virulence factor in the pathogenicity of MRSA, was found to decrease when bacterial cells were treated with BG extract. The antivirulence activities of BG were not simply due to pathogen growth inhibition; the BG extract was shown to decrease agrA, hla, sea, and seb expression in MRSA. Therefore, BG strongly reduces the secretion of the virulence factors produced by Staphylococcus aureus, suggesting that a BG-based structure may be used for the development of drugs aimed at staphylococcal virulence-related exoproteins. This study suggests that BG could be used as a promising natural compound in the food and pharmaceutical industry.

2021 ◽  
Author(s):  
Lijuan Wang ◽  
Chen Sun ◽  
Suyun Qian ◽  
Yingchao Liu ◽  
Kaihu Yao ◽  
...  

Abstract Background. Methicillin-resistant Staphylococcus aureus (MRSA) Clonal Complex 59 (CC59) clone has spread among Chinese children, resulting in many Staphylococcus aureus infections. α-hemolysin (Hlα) is an important virulence factor of Staphylococcus aureus, but little research has been done on CC59 isolates with negative α-hemolysis. Results. During the 4 periods (2009-2011, 2012-2013, 2016, 2017), 291 MRSA isolates were collected. Isolates with β and δ hemolysis accounted for 60.47% among the MRSA isolates in 2009-2011; 56.41% in 2012-2013; 77.14% in 2016; and 56.25% in 2017. most ST59 isolates (94.38%), 9 ST338 isolates (100%) showed β and δ hemolysis, both ST59 and ST338 clone belong to CC59 clone. Twenty-two ST239 isolates (73.33%), 8 ST88 isolates (80%), 4 ST5 isolates (100%), 13 ST22 isolates (92.86%) and 6 ST398 isolates (85.71%) showed α and δ hemolysis. α hemolysin in most clinical isolates is highly conservative, each showed one amino acid locus variation, the most common mutation was threonine at position 275 instead of isoleucine, then glutamic acid replaced aspartic acid at 208. Seventeen ST59 and 2 ST338 isolates had no mutation, 3 ST59 isolates showed single mutation (C448G), and only one ST59 isolate showed multilocus mutation. Other ST typing, such as ST1, ST5, ST88, ST20, ST239 and ST398, all had multilocus mutations, sites were from 3 to 8, no conservative sequence was found among isolates with the same ST typing. The carrying rates of RNA III, Rot, agrA, SarR, SarU and SigB were all over 93%, the carrying rates of SarZ and SarA genes were 41.86% and 34.88% respectively. Trancriptional levels of hlα in isolates showed α and δ hemolysis and β and δ hemolysis were equal. USA300 and R23 produced Hlα, R23 didn’t showed α hemolysis phenotype.Conclusions. Most clinical CC59 isolates from children in China were α hemolysis negative. There was no statistically significant difference in hlα gene and RNA expression, they produced the protein. The reason for the phenotypic deletion probably related to β hemolysin (Hlβ).


2021 ◽  
Vol 28 (4) ◽  
pp. 24-36
Author(s):  
Mohd Taufiq Mat Jalil ◽  
Darah Ibrahim

Background: The emergence of multidrug-resistant pathogens associated with biofilm formation can cause life-threatening infections to humans. Therefore, the present study aims to evaluate the effects of the fungal extract of Lasiodiplodia pseudotheobromae (L. pseudotheobromae) Industrial Biotechnology Research Laboratory (IBRL) OS-64 on bacterial cells and the biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA). Methods: Broth microdilution and semi-quantitative adherence assays were conducted to determine the anti-biofilm activity of the fungal extract. Light and scanning electron microscopy (SEM) analyses were performed to observe the effect of the fungal extract on biofilm formation by MRSA. Results: The transmission electron microscopy (TEM) microphotographs showed that the bacterial cells were severely damaged upon 24 h exposure to the extract and displayed several symptoms such as cell shrinkage and breakage. Meanwhile, results from the antibiofilm study indicated the extract attenuated the initial and preformed biofilms of MRSA by 80.82% and 61.39%, respectively. The initial biofilm was more sensitive to the extract compared to the pre-formed biofilm, as evidenced by the light microscopy and SEM observations that demonstrated more severe bacterial cell damage on the initial biofilms compared to pre-formed biofilms. Conclusion: The ethyl acetate extract of L. pseudotheobromae IBRL OS-64 significantly inhibited bacterial cells growth and eliminated biofilm formation by MRSA.


2020 ◽  
Vol 33 (04) ◽  
pp. 243-251
Author(s):  
Bahar Gerivani ◽  
Hamid Staji ◽  
Maryam Rassouli ◽  
Nooshin Ghazaleh ◽  
Abbas Javaheri Vayeghan

Abstract Objective Erythromycin (Ery) and leech saliva (LS) can inhibit Staphylococcus aureus growth in in vitro conditions. This study aimed to evaluate the activities and synergy between Ery and LS on chronic osteomyelitis in male Wistar rat's tibia induced by methicillin-resistant S. aureus (MRSA). Materials and Methods Four weeks after osteomyelitis induction, rats were divided into four groups including no treatment (control), Ery monotherapy (orally), LS monotherapy, or Ery + LS twice daily for 2 weeks. Staphylococcus aureus growth, pathological signs and inflammatory cytokine tumour necrosis factor-alpha (TNF-α) levels were assessed. Results Rats tolerated all therapeutic strategies well during the experiment. The Ery treatment alone significantly decreased bacterial growth, pathological signs and TNF-α levels. Leech saliva alone reduced TNF-α level significantly, but did not produce a significant reduction in bacterial growth and pathological signs. Ery + LS treatment significantly decreased bacterial growth, considerably alleviated bone pathological signs and decreased TNF-α levels compared with other groups. Statistical analysis suggested that there was a stronger efficiency and synergistic action of Ery and LS when combined against MRSA-induced osteomyelitis in rats. Clinical Significance The present study suggests that LS may have clinical utility to treat MRSA-induced osteomyelitis when combined with Ery or other therapeutics.


2020 ◽  
Vol 21 (11) ◽  
Author(s):  
Ratna Setyaningsih ◽  
Ari Susilowati ◽  
Dina Prasetyani

Abstract. Endophytic fungi associated with medicinal plants are able to produce bioactive compounds which potentially contain medicinal ingredients. Matoa (Pometia pinnata J. R. Forst & G. Forst) is one of Indonesian medicinal plants. This research aims to test antibacterial activities of ethyl acetate extract of matoa’s endophytic fungi to Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus (MRSA) and also identify isolates having high antibacterial activity. Initial test on antibacterial activity was conducted by using paper disc diffusion, while advanced test was conducted by determining minimum inhibitory concentration (MIC). The fungi were identified in morphological and molecular manner with amplification and sequencing of ITS region. Bacterial cells exposed to the extract were observed by using scanning electron microscope (SEM). Isolate AM72 was found out to have the highest antibacterial activity compared to other 12 isolates tested, with inhibition zone diameter of 31.57 mm to S. aureus and 22.87 mm to MRSA. Isolate AM72 was identified as Lasiodiplodia theobromae. Isolate BMB identified as Aspergillus oryzae produced inhibition zone with 21.96 mm diameter to S. aureus and 21.50 mm diameter to MRSA. Advanced test to isolate AM72 gave the same MIC results to S. aureus and MRSA of 1.56%. Antibacterial compound produced by isolate AM72 were found out to be able to damage bacterial cell walls. Keywords: Antibacterial, Endohpytic Fungi, Matoa, S. aureus, MRSA  


2019 ◽  
Vol 17 ◽  
pp. 205873921983838
Author(s):  
Janet R Hume ◽  
Yuan Zhang ◽  
Lei Zhang ◽  
Marnie Peterson ◽  
Deborah L Carlson

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an important cause of invasive infections, including sepsis associated with myocardial dysfunction. Caspases 1 and 11, involved in activation of the inflammasome, have been shown to be critical in response to sepsis as well as myocardial dysfunction of numerous etiologies. We examined the survival, myocardial function, and production of inflammatory mediators in mice lacking caspases 1 and 11. Cas 1/11 KO mice demonstrated no significant difference in mortality or in cardiac shortening fraction relative to control mice. Cas 1/11 KO mice had significantly reduced upregulation of expression of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the heart relative to control mice after CA-MRSA infection, as well as reduced serum production of IL-1β, TNF-α, and IL-6, with no difference in IL-10 production. Other inflammatory mediators beyond IL-1β, TNF-α, and IL-6 may be involved in myocardial dysfunction in CA-MRSA sepsis.


RSC Advances ◽  
2015 ◽  
Vol 5 (8) ◽  
pp. 5830-5845 ◽  
Author(s):  
Rashmi Gaur ◽  
Vivek Kumar Gupta ◽  
Anirban Pal ◽  
Mahendra Padurang Darokar ◽  
Rajendra Singh Bhakuni ◽  
...  

The present investigation shows that certain substituted chalcone derivatives diminish the escalation of bacterial cellsviainhibiting bacterial efflux pump and exhibit a synergistic interaction with norfloxacin.


2020 ◽  
Vol 18 (2) ◽  
Author(s):  
Mohammad Hanif Bariman ◽  
Mohammed Imad A. Mustafa Mahmoud ◽  
Hairul Aini Binti Hamzah

Introduction: Methicillin-resistant Staphylococcus aureus is globally a major public health threat. Resistance to methicillin originates from a modified protein (PBP2a) encoded by the mecA gene. The PVL gene as an important virulence factor increases the pathogenicity of MRSA. Epidemiology and characteristics of MRSA differ in different geographical regions. This study was conducted to characterize and determine the antibiotic susceptibility profile of MRSA strains isolated from patients in Hospital Tengku Ampuan Afzan, Pahang, Malaysia and to detect the presence of the mecA and PVL genes in the isolates. Materials and methods: In this study a total of 36 isolates of MRSA have been collected during a period of three months (1stFebruary –30thApril 2018). The susceptibility pattern of the isolates to ten different commonly used antibiotics were determined and the target genes were addressed by real-time PCR experiment. Results: Based on the identifying criteria, 44.4% of the isolates were CA-MRSA, and 55.5% were HA-MRSA. Resistance to oxacillin, cefoxitin and penicillin was 100%, gentamicin 88.8%, erythromycin 33.3%, tetracycline 77.7%, trimethoprim-sulfamethoxazole 61.1%, clindamycin 13.8%, chloramphenicol 11.1%, but no resistant strain of vancomycin was detected. Most of the isolates were resistant to more than three groups of antibiotics. Realtime PCR revealed that all the isolates were mecA positive and 4 isolates were PVL-positive. PVL-positive strains were CA-MRSA and susceptible to clindamycin. Conclusion: The study confirms multi-drug resistant MRSA in the study area, and shows that resistance to methicillin is mecA mediated. PVL carrier strains were present and related to CA-MRSA strains of the isolates.


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