AN IN-VITRO ANTIBIOFILM ACTIVITY OF CHLORELLA VULGARIS

Objective: Most of the microbial infection in the body is through biofilm formation. Quorum sensing (QS) is the key regulator in the biofilm formation in both Gram-negative and Gram-positive bacteria. Therefore, interfering with QS is the current strategy to prevent bacterial infection. Methods: In this study, the effect of various extracts of freshwater microalgae – Chlorella vulgaris on the growth of clinical pathogens – Pseudomonas aeruginosa and Staphylococcus aureus which were studied using minimum inhibitory concentration (MIC), antibiofilm activity, and (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay using 96-well flat bottom microtiter plates. The phytochemical analysis of C. vulgaris was also carried using standard procedure. Results: The petroleum ether, dichloromethane, chloroform, ethyl acetate, and methanolic and acetone extract of C. vulgaris showed the presence of carbohydrates, amino acids, proteins, steroids, flavonoids, alkaloids, saponins, and phenolic compounds. The MIC value of methanolic extract of C. vulgaris was found to be 1 mg/ml. The highest inhibition of 82.5% and 88.0% was shown by methanolic extract at a concentration of 1 mg/ml for P. aeruginosa and S. aureus, respectively. The antibiofilm activity by crystal violet and MTT assay confirmed the reduction of biofilm formation in both pathogenic organisms. Conclusion: The present results suggested the possible use of C. vulgaris in attenuation of QS and biofilm formation to control pathogenic bacteria – P. aeruginosa and S. aureus.

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Extract from phyllosphere bacteria with antibiofilm and quorum quenching activity to control several fish pathogenic bacteria

BMC Research Notes ◽

10.1186/s13104-021-05612-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Olivia Nathalia ◽

Diana Elizabeth Waturangi

Keyword(s):

Streptococcus Agalactiae ◽

Aeromonas Hydrophila ◽

Biofilm Formation ◽

Pathogenic Bacteria ◽

Vibrio Harveyi ◽

Quorum Quenching ◽

Indicator Bacteria ◽

Antibiofilm Activity ◽

Fish Pathogen ◽

Phyllosphere Bacteria

Abstract Objective The objective of this research were to screen quorum quenching activity compound from phyllosphere bacteria as well as antibiofilm activity against several fish pathogen bacteria such as Aeromonas hydrophila, Streptococcus agalactiae, and Vibrio harveyi. Results We found eight phyllosphere bacteria isolates with potential quorum quenching activity to inhibit Chromobacterium violaceum as indicator bacteria. Crude extracts (20 mg/mL) showed various antibiofilm activity against fish pathogenic bacteria used in this study. Isolate JB 17B showed the highest activity to inhibit biofilm formation of A. hydrophila and V. harveyi, meanwhile isolate JB 3B showed the highest activity to inhibit biofilm of S. agalactiae. From destruction assay, isolate JB 8F showed the highest activity to disrupt biofilm of A. hydrophila isolate JB 20B showed the highest activity to disrupt biofilm of V. harveyi, isolate JB 17B also showed the highest activity to disrupt biofilm of S. agalactiae.

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Anti-quorum Sensing Potential of Ageratum Conyzoides L. (Asteraceae) Extracts

10.21203/rs.3.rs-492453/v1 ◽

2021 ◽

Author(s):

Eli COMPAORE ◽

Moussa COMPAORE ◽

Vincent OUEDRAOGO ◽

Ablassé ROUAMBA ◽

Martin KIENDREBEOGO

Keyword(s):

Quorum Sensing ◽

Virulence Factors ◽

Biofilm Formation ◽

Pathogenic Bacteria ◽

Methanolic Extract ◽

Negative Impact ◽

Significant Inhibition ◽

High Morbidity ◽

Ageratum Conyzoides ◽

Phytochemical Content

Abstract Background: Pseudomonas aeruginosa causes infections in human particularly immunocompromised patients with cystic fibrosis, severe burns and HIV, resulting in high morbidity and mortality. The pathogenic bacteria P aeruginosa produces virulence factors regulated by the mechanism called quorum sensing system. Objective: The aim of this study was to assess the anti-quorum sensing activity of Ageratum conyzoides extracts Method: Chromobacterium violaceum reporter strain CV026 was used to highlight any interference with bacterium QS and strains derived from P. aeruginosa PAO1 were used to reveal any interference with the expression of quorum sensing genes, and to assess any impact of extract on the kinetics of the production of pyocyanin, elastases and biofilm formation. Results: Hydro-methanolic extract at the sub-inhibitory concentration of 100 μg/mL reduced quorum sensing virulence factors production such as, pyocyanin, elastases, rhamnolipids and biofilm formation in P. aeruginosa PAO1 after 18 hours monitoring. Extract showed significant inhibition in HSL-mediated violacein production on C. violaceum CV026 after 48 hours monitoring. Biofilm formation was inhibited up to 32%. It affected QS gene expression in PAO1. The regulatory genes lasR / rhlR and the lasI synthases were most affected. At 8hours, hydro-methanolic extract reduced both QS gene to more than 30% (lasI/lasR and rhlI/R respectively 33.8% /30.2% and 36% /33.2%). RhlA and lasB genes have been relatively affected (13.4% and 28.9%). After 18 h, this extract reduced significantly the expression of regulatory 30 genes lasR (31%) and rhlR (39.6%) although synthases genes seemed to be less affected (lasI/21.2% and rhlI/11.6%). A limited impact was observed on the downstream genes (lasB /20.0% and rhlA /15.3%). No negative impact was observed on CV026 and PAO1 growth and cell viability. Our study also showed that A. conyzoides having ample amount of phenolics, flavonoids and triterpenoids. This phytochemical content could be one of the factors for showing anti quorum potential. Conclusion: Results indicate that hydro methanol 80 % extract from A. conyzoides could be a source of potential QS inhibition compounds.

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COMPARATIVE STUDIES ON PHYTOCHEMICAL SCREENING OF FOUR DIFFERENT FLOWERS – COUROUPITA GUIANENSIS, BAUHINIA PURPUREA, STENOLOBIUM STANS, AND PLUMERIA RUBRA

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2019.v12i11.35423 ◽

2019 ◽

pp. 119-121

Author(s):

SAI NANDHINI R ◽

NIRMALA NITHYA R

Keyword(s):

Cardiac Glycosides ◽

Methanolic Extract ◽

Standard Procedure ◽

Phytochemical Analysis ◽

Phytochemical Screening ◽

Flower Extract ◽

Couroupita Guianensis ◽

Bauhinia Purpurea ◽

The Rich ◽

Plumeria Rubra

Objective: The present study aims to investigate the phytochemical from the aqueous and methanol flower extracts of four significant medicinal plants, namely, Couroupita guianensis, Bauhinia purpurea, Stenolobium stans, and Plumeria rubra. Methods: The different flowers such as C. guianensis, B. purpurea, P. rubra, and S. stans were collected from Avadi and Koyambedu market, Chennai. Standard procedure was followed for the qualitative analysis of phytocompounds. Results: Preliminary phytochemical analysis resulted that the methanolic flower extract of four plants has rich bioactive compounds comparably to the aqueous flower extracts. Tannins, saponins, flavonoids, terpenoids, and steroids were highly present in B. purpurea compared the other three flowers. Only plant P. rubra contains the rich source of cardiac glycosides in methanolic flower extract. Conclusion: From the results of the current study, we conclude that the methanolic extract of B. purpurea flower has bulk phytocompounds and can be used as a traditional medicine to treat a variety of diseases.

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Phytochemical analysis of medicinal plants of Nepal and their antibacterial and antibiofilm activities against uropathogenic Escherichia coli

BMC Complementary Medicine and Therapies ◽

10.1186/s12906-021-03293-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Sudip Bhandari ◽

Karan Khadayat ◽

Sami Poudel ◽

Sunil Shrestha ◽

Raju Shrestha ◽

...

Keyword(s):

Escherichia Coli ◽

Medicinal Plants ◽

Biofilm Formation ◽

Prunus Persica ◽

Inhibitory Concentration ◽

Total Phenolic ◽

Antibiofilm Activity ◽

Phytochemical Analysis ◽

Biofilm Inhibition ◽

E Coli

Abstract Background A biofilm is an extracellular polymeric substance (EPS) composed of polysaccharides, proteins, nucleic acids, and lipids that impede antibiotics and immune cells, thus providing a shielded environment for bacterial growth. Due to biofilm formation, some microbes can show up to 1000 fold increased resistance towards the antibiotics than the normal planktonic forms. The study was conducted to screen the crude extracts of medicinal plants used in Nepal for their in vitro antibiofilm activities. Methods Total phenolic and total flavonoid contents were determined by using a Folin-Ciocalteau reagent and aluminium trichloride method, respectively. Resazurin assay was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The initial antibiofilm activities and their inhibitory concentration (IC50) values were determined by the microtiter based modified crystal violet staining method. Results Out of 25 different plant extracts were used for the study, methanolic extracts of 20 plants showed a biofilm inhibition activity against five different strong biofilm producing Escherichia coli strains. Calotropis gigantea exhibited inhibition against all five different E. coli strains with IC50 values ranging from 299.7 ± 20.5 to 427.4 ± 2.7 μg/mL. Apart from that, Eclipta prostrata also showed biofilm formation inhibition, followed by Eupatorium adenophorum, Moringa oleifera, Ocimum tenuifolium, Oxalis lantifolia, Prunus persica, and Urtica parviflora. The extracts of C. gigantea, E. prostrata, Mangifera indica, O. tenuifolium, P. persica, and U. parviflora exhibited a moderate to poor MIC value ranging from 625 to 2500 μg/mL. The highest amount of phenolic content (TPC) was found in Acacia catechu followed by Morus alba, which was 38.9 and 25.1 mg gallic acid equivalents, respectively. The highest amount of flavonoid content was found in A. catechu followed by M. indica, which was 27.1 and 20.8 mg quercetin equivalents, respectively. Conclusion Extracts of C. gigantea, E. prostrata, P. persica, U. parviflora, and O. tenuifolium showed antibacterial as well as antibiofilm activity against pathogenic and strong biofilm producing E. coli. Thus, extracts or the pure compound from these medicinal plants could be used as antibiotics in the future.

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Nephroprotective Effect of Cissampelos owariensis Extract on Renal Histomorphology of Wistar Rats during Exposure to Carbon Tetrachloride- induced Nephropathy

Asian Journal of Biology ◽

10.9734/ajob/2019/v8i430071 ◽

2020 ◽

pp. 1-10

Author(s):

Dayo Rotimi Omotoso ◽

Olayinka Simbiat Lawal ◽

Oluwasegun Davies Olatomide ◽

Itohan Grace Okojie

Keyword(s):

Phenolic Compounds ◽

Treatment Group ◽

Wistar Rats ◽

Methanolic Extract ◽

Kidney Tissue ◽

Antioxidant Property ◽

The Body ◽

Control Group ◽

Phytochemical Analysis ◽

Histopathological Changes

To assess nephroprotective potency of methanolic extract of C. owariensis on renal histomorphology of Wistar rats during exposure to nephropathic activity of CCl4. Twenty eight (28) albino Wistar rats divided into four groups which include normal control group administered with vehicles -distilled water (1 ml/kg b.w.) and olive oil (3 ml/kg b.w.), experimental control group administered with CCl4 (3 ml/kg b.w.) twice a week, first treatment group administered with CCl4 (3 ml/kg b.w.) twice a week + methanolic extract of C. owariensis (100 mg/kg b.w.) daily and second treatment group administered with CCl4 (3 ml/kg b.w.) twice a week + methanolic extract of C. owariensis (300 mg/kg b.w.) daily for twenty eight (28) days. Phytochemical analysis of methanolic extract of C. owariensis was carried out using GC-MS. The body weight of study animals was measure at days 0, 7, 14, 21 and 28 of study. Then, kidney tissue of study animals was collected, weighed and processed for histopathological study. Tissue sections were stained using H & E, examined under microscope, photomicrographs were generated and observable histopathological changes were quantified using image-J software. Phytochemical analysis of methanolic extract of C. owariensis showed abundance of phenolic compounds which may in turn confer antioxidant property on the extract. Results of this study also showed that treatment with extract helped to reduce body and tissue weight loss that follows exposure to CCl4. Also, treatment with the extract helped to reduce significantly (p < 0.05) renal histopathological changes following exposure to CCl4. The methanolic extract of C. owariensis contains abundant phenolic compounds which confer antioxidant property that in turn mediate the nephroprotective potency of the extract against nephropathic effect of CCl4.

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Antimicrobial Efficacy of Methanolic and Aqueous Extracts of Partially Purified Protein from Young and Matured Root of Guiera senegalensis (Moshi Medicine)

International Journal of Biochemistry Research & Review ◽

10.9734/ijbcrr/2020/v29i530189 ◽

2020 ◽

pp. 30-39

Author(s):

M. K. Jiyil ◽

M. I. Shago ◽

C. E. Mafuyai ◽

M. Silas ◽

O. A. Olorunyomi

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Candida Albicans ◽

Pathogenic Bacteria ◽

Standard Procedure ◽

Phytochemical Analysis ◽

Gel Chromatography ◽

Aqueous Extracts ◽

Young Root ◽

Guiera Senegalensis

Background: Antibiotic resistance among pathogenic bacteria is increasing at an alarming rate leading to the need for traditional medicine as an alternative. Aim of the Study: The study aimed to evaluate the antimicrobial activity of methanolic and, aqueous extracts of partial purified protein of young and matured roots of Guiera senegalensis. Methodology: Antimicrobial activity was determined by disc diffusion and broth dilution techniques, Quantitative phytochemical analysis was carried out by standard procedure, the gel chromatography technique was used to fractionate the crude protein. The test isolates were Bacillus subtilis, Staphylococcus aureus, E. coli, Salmonella typhimurium and Candida albicans. Results: The antimicrobial activity showed all the extracts were quite effective against most of the test isolates except Candida albicans (fungus). The crude and partially purified proteins were active against Gram-positive bacteria. The maximum zone of inhibition (37.33±5.03b mm) was observed in methanolic extracts of young root against Staphylococcus aureus at 100 mg/ml. Most extracts of methanolic exhibited minimum inhibitory concentration (MIC) at the range of 6.25 mg/ml and 12.5 mg/ml and minimum bactericidal concentration (MBC) at 12.5 mg/ml and 25 mg/ml. The young root was more active than the matured root. Quantitative phytochemicals showed a high amount of saponins (9.98% and 6.42%) in matured and young roots respectively. Conclusion: Guiera senegalensis has broad-spectrum antimicrobial activity and a potential source of new antibiotics that could be useful for the treatment of infectious diseases.

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Antibiofilm Activity of Small-Molecule ZY-214-4 Against Staphylococcus aureus

Frontiers in Microbiology ◽

10.3389/fmicb.2021.618922 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jingyi Yu ◽

Lulin Rao ◽

Lingling Zhan ◽

Yan Zhou ◽

Yinjuan Guo ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Small Molecule ◽

Biofilm Formation ◽

Laser Scanning ◽

Pathogenic Bacteria ◽

Cell Aggregation ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Antibiofilm Activity ◽

Subinhibitory Concentration

Staphylococcus aureus is the most important pathogenic bacteria in humans. As the resistance of S. aureus to existing antibiotics is increasing, there is an urgent need for new anti-infective drugs. S. aureus biofilms cause persistent infections and resist complete eradication with antibiotic therapy. The present study investigated the inhibitory effect of the novel small-molecule ZY-214-4 (C19H11BrNO4) on S. aureus biofilm formation. At a subinhibitory concentration (4 μg/ml), ZY-214-4 had no effect on the growth of S. aureus strains and also showed no cytotoxicity in human normal bronchial epithelial cells (Bease-2B). The results of a semi-quantitative biofilm test showed that ZY-214-4 prevented S. aureus biofilm formation, which was confirmed by scanning electron microscopy and confocal laser scanning microscopy. ZY-214-4 significantly suppressed the production of polysaccharide intercellular adhesion and prevented cell aggregation, and also inhibited the mRNA expression of icaA and other biofilm-related genes (eno, clfA/B, fnbB, fib, ebpS, psmα, and psmβ) in clinical S. aureus isolates. Thus, at a subinhibitory concentration, ZY-214-4 inhibits biofilm formation by preventing cell aggregation, highlighting its clinical potential for preventing or treating S. aureus infections.

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Phytochemical Composition, Antibacterial, and Antibiofilm Activity of Malva sylvestris Against Human Pathogenic Bacteria

Jundishapur Journal of Natural Pharmaceutical Products ◽

10.5812/jjnpp.114164 ◽

2021 ◽

Vol In Press (In Press) ◽

Author(s):

Mahmoud Fathi ◽

Maryam Ghane ◽

Leila Pishkar

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

High Performance ◽

Pathogenic Bacteria ◽

Inhibitory Concentration ◽

Methanolic Extract ◽

Biologically Active ◽

Diffusion Method ◽

Antibiofilm Activity ◽

Malva Sylvestris

Background: Considering the increased rate of microbial resistance to antibiotics and chemical side effects of antibiotics, there is a need for an alternative antimicrobial agent with fewer complications. Medicinal plants are rich resources of phytochemical compounds with antibacterial activity that could fight off this problem. Objectives: The aim of this research was to investigate the chemical composition, antimicrobial, and antibiofilm properties of Malva sylvestris on some pathogenic bacteria. Methods: Antibacterial effect of the extract was assessed by the well diffusion and broth microdilution methods against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli. The anti-biofilm property of the extract was also examined using the crystal violet assay. Finally, the chemical constituents and total phenols of the extract were determined by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC), respectively. Results: The methanolic extract of M. sylvestris showed antimicrobial activity against all tested Gram-negative and Gram-positive strains by the agar well diffusion method. The minimum inhibitory concentration (MIC) of the extract ranged from 21.9 ± 0.1 to 51.9 ± 0.5 mg/mL against the tested microorganisms. In addition, the minimum bactericidal concentration (MBC) spanned from 43.7 ± 0.1 to 85.8 ± 0.3 mg/mL. The biofilm inhibitory concentration (BIC50) of the extract was found to be 40 - 87 mg/mL against the tested bacteria. Analysis of the extract by GC-MS indicated that the most abundant compounds were 1-heptacosanol (38.41%), 17-Pentatriacontene (19.78%), and 6,9,12,15-docosatetraenoic acid, methyl ester (8.08%). High-performance liquid chromatography confirmed the presence of apigenin (6.84 ppm) and salicylic acid (1.5 ppm) as phenolic compounds in M. sylvestris methanolic extract. Conclusions: The results of this study represent the high potency of M. sylvestris extract as a source of biologically-active compounds for the development of future phytotherapeutic products with antibacterial and antibiofilm activity.

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Antibiofilm Action of ZnO, SnO2 and CeO2 Nanoparticles Towards Grampositive Biofilm Forming Pathogenic Bacteria

Recent Patents on Nanotechnology ◽

10.2174/1872210514666200313121953 ◽

2020 ◽

Vol 14 (3) ◽

pp. 239-249 ◽

Cited By ~ 2

Author(s):

Fazlurrahman Khan ◽

Jang-Won Lee ◽

Dung N.T. Pham ◽

Mohammad M. Khan ◽

Seul-Ki Park ◽

...

Keyword(s):

Biofilm Formation ◽

Metallic Nanoparticles ◽

Pathogenic Bacteria ◽

Antibacterial Properties ◽

Antibiofilm Activity ◽

Amyloid Protein ◽

Human Pathogens ◽

Zno Nps ◽

Wide Range

Background: The ability to form biofilm and produce several virulence factors has caused numerous human pathogens to become tremendously resistant towards traditional antibiotic treatments, thus, new alternative strategies are urgently in demand. One of the strategies that have recently been developed involves the application of metallic Nanoparticles (NPs). Up to the present, promising results in terms of antimicrobial and antibiofilm activities have been observed in a wide range of metal NPs. Methods: The present study has selected three metal oxides such as ZnO, SnO2 and CeO2 NPs to comparatively investigate their antibiofilm and antibacterial properties against two Gram-positive human pathogens, which are Listeria monocytogenes and Staphylococcus aureus. Result: The anti-biofilm activities of ZnO, SnO2 and CeO2 NPs against S. aureus and L. monocytogenes were assayed by crystal violet staining and confirmed by microscopic visualization using SEM. The synthesis of amyloid protein by S. aureus and exopolysaccharide by L. monocytogenes in the presence of ZnO, SnO2 and CeO2 NPs was evaluated by Congo red assay. Conclusion: Overall, these results indicated that ZnO, SnO2 and CeO2 NPs can be considered as potential agents for treating the infections caused by L. monocytogenes and S. aureus, especially those associated with biofilm formation. Based on the present study, further studies are required to understand their mechanisms at both phenotypic and molecular levels, as well as their in vivo cytotoxicity, thereby enabling the applications of these metal oxide NPs in biomedical fields and food industry. Discussion: Results have shown that ZnO, SnO2 and CeO2 NPs effectively inhibited biofilm formation of both L. monocytogenes and S. aureus. The microscopic analysis also confirmed the antibiofilm activity of these NPs. It was also found that only ZnO NPs inhibited cell growth as well as the production of amyloid protein in S. aureus.

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Antibiofilm and antivirulence effect of stilbenes on clinically relevant staphylococci

10.5194/biofilms9-32 ◽

2020 ◽

Author(s):

Petra Kašparová ◽

Olga Maťátková

Keyword(s):

Cell Surface ◽

Biofilm Formation ◽

Pathogenic Bacteria ◽

Wide Spectrum ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Antibiofilm Activity ◽

Host Immune System ◽

Abiotic Surfaces ◽

Antibiotic Compounds

Genus Staphylococcus comprises many greatly pathogenic species like S.&#160;aureus, S.&#160;epidermidis or S. saprophyticus. The great pathogenicity of stated species is often facilitated by their capability to form thick complex biofilms on various biotic or abiotic surfaces. Biofilm formation together with extracellular hydrolases or toxins represents important virulence factor, which increases persistence of staphylococci in host via enhancing their ability to evade host immune system and further promote the infection development. With an increased emergence of antibiotic resistance among pathogenic bacteria including staphylococci the search for novel antibiotic compounds with antivirulence effect is sought. Such substances might be stilbenes, phenolic compounds isolated from various plants (Vitis&#160;spp., Vaccinium spp., Pterocarpus spp., Pinus spp.). They possess strong antioxidant activity and a wide spectrum of beneficial pharmacological effects (antitumor, hypolipidemic, hypoglycemic). Apart from that, they also have great antimicrobial activity with a potent ability to enhance antibiotics action in combination. Presented work focused on resveratrol, pterostilbene (PTE) and pinosylvine and their effect on S. aureus and S. epidermidis biofilm formation. The effect of stilbene representatives on production of other virulence factors (proteases, phospholipases, haemolysins), cell surface hydrophobicity and morphology was also observed. PTE was found to be the most effective among studied stilbenes against S. aureus and S. epidermidis biofilm with minimum biofilm inhibitory concentrations (MBIC80) ranging from 40 to 130 mg/l. Its effect on mature staphylococcal biofilm eradication was even greater with 80% eradication rate achieved by 40-75 mg/l. PTE (49 mg/l) was found to have a potent combinatory antibiofilm activity with erythromycin or tetracycline (5 mg/l both) causing more than 80% inhibition in metabolic activity of biofilm cells. It was able to permeabilize cytoplasmic membrane, thus probably enabling antibiotic uptake by the cell. PTE also altered cell surface hydrophobicity and production of haemolysin. PTE might be the solution to increasing biofilm-related resistance problem and a promising candidate with antibiofilm and antivirulence potential for future antibiotic treatment of staphylococcal infections. &#160; This work was supported by the grant of Specific university research &#8211; grant No. A2_FPBT_2020_004.

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