Antiadhesion and antibiofilm potential of Fagonia indica from Cholistan desert against clinical multidrug resistant bacteria

High resistance to antimicrobials is associated with biofilm formation responsible for infectious microbes to withstand severe conditions. Therefore, new alternatives are necessary as biofilm inhibitors to control infections. In this study, the antimicrobial and antibiofilm activities of Fagonia indica extracts were evaluated against MDR clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica has antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against multidrug resistant (MDR) clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica had antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against MDR isolates. The maximum inhibitory effects of Fagonia indica chloroform extract on biofilm formation was observed on Staphylococcus aureus (71.84%) followed by Klebsiella pneumoniae (70.83%) after 48 hrs showing that inhibition is also time dependent. Our results about bacterial cell protein leakage indicated that MDR isolates treated with chloroform extract of Fagonia indica showed maximum protein leakage of K. pneumoniae (59.14 µg mL-1) followed by S. aureus (56.7 µg mL-1). Cell attachment assays indicated that chloroform extract resulted in a 43.5-53.5% inhibition of cell adherence to a polystyrene surface. Our results revealed that extracts of Fagonia indica significantly inhibited biofilm formation among MDR clinical isolates, therefore, could be applied as antimicrobial agents and cost effective biofilm inhibitor against these MDR isolates.

Antimicrobial activity of essential oils against Pasteurella spp. isolated from the oral cavity of domestic cats

ABSTRACT: Pasteurella spp. have been identified predominantly in the oral microbiota of domestic cats. However, Pasteurella spp. was significantly more prevalent in cats with inflammatory oral disease; and consequently, it was considered as part of the etiology in this disease. In addition, in animals, Pasteurella spp. have become increasingly resistant to a large number of antimicrobials. Natural products, especially essential oils, could contribute to minimizing this issue. This study determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of six essential oils against Pasteurella spp. isolates from the oral cavity of domestic cats. Our results showed that essential oils with better antimicrobial effectiveness against most of the Pasteurella isolates were lemongrass, tea tree and clove, with inhibition values between 50 to 800 µg mL-1. All essential oils showed bacteriostatic activity against the species of Pasteurella isolated from the domestic cats. These results suggested that lemongrass, tea tree and clove oils have potential to be used in products for oral hygiene and treatment of oral infections in domestic cats.

https://acgpubs.org/doc/20220107214746A3-RAFC-2107-2149.pdf

In this study, antibacterial and antifungal properties of four medlar extracts obtained using four different solvents, ethanol, methanol, acetone and water, were investigated. The disk diffusion method was used to determine the antimicrobial effects of the extracts. In addition, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) values were determined. The antibacterial effect of the pure water extract of medlar on S. aureus bacteria was found to be high (11.46 mm). In addition, the MIC and MBC values of the pure water extract were determined as 35.15 and 23.39 µg/mL for S. aureus bacteria. When the antifungal effect was examined, the antifungal effect of the pure water extract of medlar against P. crysogenum was found to be high (14.00 mm). The MIC and MFC values of the pure water extract of medlar are 23.43 and 11.72 µg/mL for P. crysogenum, respectively. Therefore, it was concluded that the pure water extract had the highest antimicrobial effect.

Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) for Twelve Antimicrobials (Biocides and Antibiotics) in Eight Strains of Listeria monocytogenes

When selecting effective doses of antimicrobials, be they biocides or antibiotics, it is essential to know the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of these substances. The present research determined the MICs and MBCs for three biocides, sodium hypochlorite (SH), benzalkonium chloride (BC), and peracetic acid (PAA), and nine antibiotics in eight strains of Listeria monocytogenes of varying serotypes. Marked intra-species differences were observed in the resistance of L. monocytogenes to the biocides and antibiotics. The MICs (ppm) for the biocides ranged between 1750 and 4500 for SH, 0.25 and 20.00 for BC, and 1050 and 1700 for PAA. Their MBCs (ppm) ranged from 2250 to 4500 for SH, 0.50 to 20.00 for BC, and 1150 to 1800 for PAA. The MICs (ppm) for antibiotics lay between 1 and 15 for ampicillin, 8 and 150 for cephalothin, 20 and 170 for cefoxitin, 0.05 and 0.20 for erythromycin, 4 and 50 for chloramphenicol, 3 and 100 for gentamicin, 2 and 15 for tetracycline, 2 and 80 for vancomycin, and 160 and 430 for fosfomycin. The corresponding MBCs (ppm) were from 5 to 20 for ampicillin, 9 to 160 for cephalothin, 70 to 200 for cefoxitin, 4 to 5 for erythromycin, 9 to 70 for chloramphenicol, 5 to 100 for gentamicin, 3 to 30 for tetracycline, 3 to 90 for vancomycin, and 160 to 450 for fosfomycin. Notably, erythromycin showed considerable efficacy, demonstrated by the low values for both MIC and MBC. Based on EUCAST and the CLSI criteria, all strains were susceptible to erythromycin. All strains were resistant to cephalothin, cefoxitin, gentamicin, and fosfomycin. Further values for resistance were 87.50% for ampicillin and vancomycin, 75.00% for tetracycline, and 62.50% for chloramphenicol. The high prevalence of antibiotic resistance is a matter for concern. A positive correlation was found between MIC and MBC values for most of the biocides and antibiotics. The higher the hydrophobicity of the cell surface, the higher the susceptibility to biocides, suggesting that surface characteristics of bacterial cells influence resistance to these compounds.

The in vitro efficacy of neutral electrolysed water and povidone-iodine against CRS-associated biofilms

Background: Despite best medical and surgical practice, some cases of chronic rhinosinusitis (CRS) can remain recalcitrant. Bacterial biofilms have been associated with the recalcitrance of sinonasal inflammation. Biofilms are highly resistant to commonly prescribed antibiotics. Accordingly, more effective antimicrobial treatment options are needed to treat refractory CRS. The aim of this study was to determine the in vitro efficacy of neutral electrolysed water (NEW) and povidone-iodine (PVI) against CRS-associated Staphylococcus aureus biofilms. Methods: Mature S. aureus biofilms were grown in a Centre for Disease Control (CDC) biofilm reactor. The antimicrobial activity of NEW, PVI and doxycycline was determined for both planktonic and biofilm cultures of a clinical S. aureus isolate using minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum biofilm eradication concentration (MBEC) assays. Results: MICs and MBCs were determined for all antimicrobials. MBC values were similar to MICs for both antiseptics, but doxycycline MBCs were significantly higher than the associated MICs. Biofilms were highly resistant to NEW and doxycycline. The MBEC for doxycycline was between 500 and 1000 µg/mL. NEW was ineffective against biofilms and no MBEC could be determined. In contrast, a concentration of 10% of the commercial PVI solution (10 mg/mL PVI) led to effective eradication of mature biofilms. Conclusion: In this study, only PVI showed promising antibiofilm activity at physiological concentrations. The in vivo efficacy of PVI warrants further investigation of its potential as a treatment for recalcitrant CRS.

Comparative Study of Phenolic Compound Antioxidant and Antimicrobial Activities of Fruits Peel and Cladodes from Tunisian Opuntia Stricta

Similarly, the bacterial strains tested were most sensitive to fruit peels than especially against Staphylococcus aureus with inhibition zones (DIZ), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 15.22±2.14 mm, 4.68 mg/mL and 37.5 mg/mL respectively. However, aqueous extract of cladodes have high antifongical activity particularly against Fusarium oxysporum with DIZ (20±0.2 mm), MIC (4.68mg/mL) and MFC (75 mg/mL) value

Multi-Omics Analysis Reveals Anti-Staphylococcus aureus Activity of Actinomycin D Originating from Streptomyces parvulus

Staphylococcus aureus (S. aureus) is a common pathogen that causes various serious diseases, including chronic infections. Discovering new antibacterial agents is an important aspect of the pharmaceutical field because of the lack of effective antibacterial drugs. In our research, we found that one anti-S. aureus substance is actinomycin D, originating from Streptomyces parvulus (S. parvulus); then, we further focused on the anti-S. aureus ability and the omics profile of S. aureus in response to actinomycin D. The results revealed that actinomycin D had a significant inhibitory activity on S. aureus with a minimum inhibitory concentration (MIC) of 2 μg/mL and a minimum bactericidal concentration (MBC) of 64 μg/mL. Bacterial reactive oxygen species (ROS) increased 3.5-fold upon treatment with actinomycin D, as was measured with the oxidation-sensitive fluorescent probe DCFH-DA, and H2O2 increased 3.5 times with treatment by actinomycin D. Proteomics and metabolomics, respectively, identified differentially expressed proteins in control and treatment groups, and the co-mapped correlation network of proteomics and metabolomics annotated five major pathways that were potentially related to disrupting the energy metabolism and oxidative stress of S. aureus. All findings contributed to providing new insight into the mechanisms of the anti-S. aureus effects of actinomycin D originating from S. parvulus.

Insights into the mechanism of Cymbopogan martinii essential oil in topical therapy of acne vulgaris

Aim: The present study investigated the essential oil of Cymbopogan martinii (palmarosa oil; PRO) as a potential topical therapy in acne vulgaris. Materials & methods: GC-MS profiling and biocompatibility studies of PRO were undertaken. The antimicrobial potential was assessed against Cutibacterium acnes. anti-inflammatory, antityrosinase activity and lipid peroxidation were also evaluated. Results: Geraniol was identified as the major phytoconstituent, and the oil was found to be safe for topical application. The minimum inhibitory concentration and minimum bactericidal concentration values were noted as 16 μl/ml. PRO reduced the cytokine levels of TNF-α, IL-12 and IL-8 and inhibited tyrosinase. A low concentration of the oil (up to 0.5 μl/ml) produced malondialdehyde levels equivalent to that of untreated cells. Conclusion: PRO may prove useful as a natural topical agent in the management of acne.

Aktivitas antibakteri ekstrak kulit jeruk nipis (Citrus aurantifolia) terhadap bakteri Prevotella intermediaAntibacterial activity of lime (Citrus aurantifolia) peel extract towards Prevotella intermedia

Pendahuluan: Prevotella intermedia merupakan salah satu bakteri utama pada penyakit periimplantitis. Periimplantitis merupakan inflamasi jaringan lunak dan keras disekitar implan yang dapat dicegah menggunakan ekstrak tanaman antibakteri. Salah satunya yaitu kulit jeruk nipis, yang dapat menghambat proses inflamasi karena mengandung alkaloid, steroid, saponin, flavonoid, tanin sebagai senyawa antibakteri. Penelitian ini bertujuan untuk mengetahui peranan antibakteri kulit jeruk nipis dengan mengukur Konsentrasi Hambat Minimal (KHM) dan Konsentrasi Bunuh Minimal (KBM) ekstrak kulit jeruk nipis terhadap pertumbuhan bakteri Prevotella intermedia. Metode: Eksperimental laboratorium dengan rancangan penelitian post test only control group design. Pengujian KHM dan KBM dilakukan dengan metode dilusi, kulit jeruk nipis dimaserasi menggunakan pelarut etanol 70% sehingga didapatkan ekstrak kulit jeruk nipis dengan konsentrasi 0,78, 1,56, 3,125, 6,25, 12,5, 25, 50, dan 100% dengan chlorhexidine sebagai kontrol positif dan akuades sebagai kontrol negatif. Media kultur bakteri menggunakan Tripton Soya Agar. Hasil: Berdasarkan analisis statistik menggunakan Kruskal Wallis menunjukkan perbedaan penurunan jumlah koloni bakteri yang signifikan (p=0,0001) pada KBM dan KHM dari berbagai konsentrasi ekstrak kulit jeruk nipis terhadap pertumbuhan bakteri Prevotella intermedia, uji lanjutan Mann Whitney menunjukkan perbedaan penurunan jumlah koloni bakteri yang signifikan (p=0,021) antar masing-masing konsentrasi dan kelompok kontrol. Simpulan: Konsentrasi hambat minimal ekstrak kulit jeruk nipis terhadap bakteri Prevotella intermedia 12,5%, konsentrasi bunuh minimalnya 25%. Kata kunci: agen antibakteri; ekstrak jeruk nipis; Prevotella intermediaABSTRACTIntroduction: Prevotella intermedia is one of the main bacteria in periimplantitis. Periimplantitis is inflammation of the soft and hard tissues around the implant that can be prevented using antibacterial plant extracts. One of them is lime peel, which can inhibit the inflammatory process due to its alkaloids, steroids, saponins, flavonoids, and tannins as antibacterial compounds. This study was aimed to determine the antibacterial activity of lime peel by measuring the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of lime peel extract on the growth of Prevotella intermedia. Methods: Experimental laboratory with post-test only control group design. The MIC and MBC tests were performed by the dilution method. The lime peel was macerated using 70% ethanol solvent to obtain lime peel extract with concentrations of 0.78, 1.56, 3.125, 6.25, 12.5, 25, 50, and 100% with chlorhexidine as a positive control and aquadest as a negative control. Bacterial culture media using Tripton Soy Agar. Results: Based on statistical analysis using Kruskal Wallis showed a significant difference in the decrease of the number of bacterial colonies (p=0.0001) in MBC and MIC from various concentrations of lime peel extract on the growth of Prevotella intermedia bacteria. Furthermore, the Mann Whitney follow-up test showed differences in the decrease of the number of bacterial colonies, which was significant (p=0.021) between each concentration and control group. Conclusions: The minimum inhibitory concentration of lime peel extract towards the growth of Prevotella intermedia was 12.5%, with the minimum bactericidal concentration of 25%. Keywords: antibacterial agent; citrus extracts; Prevotella intermedia

Antimicrobial Activities of Laurus nobilis Leaves Ethanol Extract on Staphylococcus aureus, Salmonellae typhi, and Escherichia coli.

Laurus nobilis is one of the most well-known, most frequently used plants is from Lauraceae family which contains up 2.500 species that grow in the subtropics and tropics of the Mediterranean region and Indonesia. This study was supposed to investigate the antimicrobial eff ect of L.nobilis leaves ethanol extract on Staphylococcus aureus, Salmonellae typhi, and Escherichia coli. This preliminary study examined the antimicrobial eff ect of L.nobilis leaves ethanol extract. The method used Agar-well diff usion for determination of the zone of inhibition and the minimum bactericidal concentration to investigate the activity of L.nobilis leaves ethanol extract at 100% concentration . The results revealed that extract of L. nobilis leaves had the antibacterial activity against Staphylococcus aureus with a zone of inhibition (16.3 ±1.5 mm), Staphylococcus aureus with (14.5±0.5 mm), and weak antimicrobial activity against Escherichia coli (11.3±1.1mm). Also, through the minimum bactericidal concentration experiment, the L.nobilis leaves ethanol extract had activity on Staphylococcus aureus and Salmonellae typhi, it’s killed the bacteria in all concentration start it from 5×107 to 5×104. But the activity on Escherichia coli just weaken concentration 5×107 and 106. This research has concluded that the L.nobilis leaves ethanol extract exhibited a signifi cant antimicrobial eff ect against Staphylococcus aureus and Salmonellae typhi then Escherichia coli that is considered a kind of multidrug-resistant bacteria.