scholarly journals Antimicrobial Activity of Snake β-Defensins and Derived Peptides

Toxins ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 1
Author(s):  
Nancy Oguiura ◽  
Poliana Garcia Corrêa ◽  
Isabella Lemos Rosmino ◽  
Ana Olívia de Souza ◽  
Kerly Fernanda Mesquita Pasqualoto
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Micrococcus Luteus ◽  
Peptide Sequence ◽  
Tryptophan Residue ◽  
High Antimicrobial Activity ◽  
Bacteria And Fungi ◽  
Microbroth Dilution ◽  
And Staphylococcus Aureus

β-defensins are antimicrobial peptides presenting in vertebrate animals. They participate in innate immunity, but little is known about them in reptiles, including snakes. Although several β-defensin genes were described in Brazilian snakes, their function is still unknown. The peptide sequence from these genes was deduced, and synthetic peptides (with approximately 40 amino acids and derived peptides) were tested against pathogenic bacteria and fungi using microbroth dilution assays. The linear peptides, derived from β-defensins, were designed applying the bioisosterism strategy. The linear β-defensins were more active against Escherichia coli, Micrococcus luteus, Citrobacter freundii, and Staphylococcus aureus. The derived peptides (7–14 mer) showed antibacterial activity against those bacteria and on Klebsiella pneumoniae. Nonetheless, they did not present activity against Candida albicans, Cryptococcus neoformans, Trychophyton rubrum, and Aspergillus fumigatus showing that the cysteine substitution to serine is deleterious to antifungal properties. Tryptophan residue showed to be necessary to improve antibacterial activity. Even though the studied snake β-defensins do not have high antimicrobial activity, they proved to be attractive as template molecules for the development of antibiotics.

scholarly journals Preliminary phytochemical screening and susceptibility of bacteria pathogens to whole extract of evolvulus alsinoides (L.)

1970 ◽  
Vol 18 ◽  
pp. 16-20
Author(s):  
BA Omogbai ◽  
FA Eze
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Bacillus Cereus ◽  
Pathogenic Bacteria ◽  
Volatile Oil ◽  
Salmonella Typhi ◽  
Phytochemical Screening ◽  
Evolvulus Alsinoides ◽  
And Staphylococcus Aureus

Context: Plant based antimicrobial represent a vast untapped source for medicines and further exploration of plant antimicrobial neeto occur. Evolvulus alsinoides (L) (Convolvulaceae) is a perennial herb is used in traditional medicine in East Asia, India, Africa and Philippines to cure fever, cough, cold, venereal diseases, azoospermia, adenitis and dementia.   Objective: The objective of this research was to evaluate the antimicrobial activity of the extracts of E. alsinoides on some clinical microbial isolates.   Materials and Methods: The ed thanolic and aqueous extracts of the whole plant (leaves and twigs) were analysed for alkanoids, tannins, glycosides, steroids, flavonoids, saponins, volatile oil and resins. The determination of antibacterial activity was done using the agar well diffusion technique. Pure cultures of pathogenic bacteria such as Bacillus cereus, Staphylococcus aureus, Micrococcus leutus, Klebsiella Pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi were used for antibacterial activity assay, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).   Results: The ethanolic extract of the plant had MIC values ranging from 16 mg/ml to 512.5 mg/ml. The least MIC was 16mg-ml against Salmonella typhi while Bacillus cereus and Staphylococcus aureus showed the highest MIC of 512.5 mg-ml. In the aqueous extract the MIC ranged between 512.5 to >1025 mg/ml. Salmonella typhi, Micrococcus luteus and Staphylococcus aureus were not inhibited by the water extract. Phytochemical result showed ethanol to be a better solvent for the extraction of the bioactive agents in this plant which include: glycosides, alkaloids, saponins, tannins, flavonoids and volatile oil.   Conclusion: In this study the gram-negative organisms had the lowest MICs and MBCs. This suggests their higher susceptibility to the extract of this plant. On the basis of the result obtained in this investigation it can be concluded that ethanol extract of Evolvulus alsinoides had significant in vitro broad spectrum antimicrobial activity.   Keywords: Evolvulus alsinoides; Phytochemical screening; Antibacterial activity. DOI: http://dx.doi.org/10.3329/jbs.v18i0.8769 JBS 2010; 18(0): 16-20

scholarly journals Comparative study of antibacterial activity of two different earthworm species, Perionyx excavatus and Pheretima posthuma against pathogenic bacteria

2015 ◽  
Vol 7 (2) ◽  
pp. 666-671 ◽  
Author(s):  
Nitish Bansal ◽  
R. K. Gupta ◽  
Dharambir Singh ◽  
Shashank Shashank
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Micrococcus Luteus ◽  
Disease Outbreaks ◽  
Biologically Active ◽  
Bacterial Strains ◽  
Perionyx Excavatus ◽  
Shigella Spp ◽  
Aquaculture Production

Disease outbreaks are being increasingly recognized as a significant constraint on aquaculture production and trade affecting the economic development of the sector in many countries. Extracting and using biologically active compounds from earthworms has traditionally been practiced by indigenous people throughout the world. The aim of the present study was to shown antimicrobial activity through earthworm extract against fish bacterial pathogens. In total, 8 bacterial strains i.e. 6 gram negative viz. Aeromonas hydrophila, Pseudomonas aeruginosa, P. fluorescens, E.coli, Enterobacter aerogens and Shigella sp. and 2 gram positive viz. Staphylococcus aureus and Micrococcus luteus were identified. The extract of earthworm Perionyx excavatus, Pheretima posthuma were prepared and antimicrobial activity of the extract was determined by antimicrobial well diffusion assay. After 24 hrs of incubation period, it was observed that earthworm extract showed antibacterial activity against isolated bacterial strains. Among earthworm extract of two different species, the maximum zone of inhibition was shown against A. hydrophila by Perionyx excavatus (18.33± 0.66 mm) and P. posthuma (16.66±0.33). P. excavatus showed antibacterial activity against all pathogenic bacteria except Shigella spp. However on the other hand, P.posthuma showed antibacterial activity against A. hydrophila, P. fluorescens, E.coli, and S. aureus. The study has proved that earthworm extract can be effectively used for suppression of bacterial infection in fishes and that it can used as potential antimicrobial drug against commercial antibiotic resistance bacteria.

scholarly journals Proliferation of Antibiotic-Producing Bacteria and Concomitant Antibiotic Production as the Basis for the Antibiotic Activity of Jordan's Red Soils

2009 ◽  
Vol 75 (9) ◽  
pp. 2735-2741 ◽  
Author(s):  
Joseph O. Falkinham ◽  
Thomas E. Wall ◽  
Justin R. Tanner ◽  
Khaled Tawaha ◽  
Feras Q. Alali ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Incubation Period ◽  
Micrococcus Luteus ◽  
Antibiotic Production ◽  
Antibiotic Activity ◽  
Skin Infections ◽  
High Antimicrobial Activity ◽  
Methanol Extracts ◽  
Red Soils

ABSTRACT Anecdotes, both historical and recent, recount the curing of skin infections, including diaper rash, by using red soils from the Hashemite Kingdom of Jordan. Following inoculation of red soils isolated from geographically separate areas of Jordan, Micrococcus luteus and Staphylococcus aureus were rapidly killed. Over the 3-week incubation period, the number of specific types of antibiotic-producing bacteria increased, and high antimicrobial activity (MIC, ∼10 μg/ml) was observed in methanol extracts of the inoculated red soils. Antibiotic-producing microorganisms whose numbers increased during incubation included actinomycetes, Lysobacter spp., and Bacillus spp. The actinomycetes produced actinomycin C2 and actinomycin C3. No myxobacteria or lytic bacteriophages with activity against either M. luteus or S. aureus were detected in either soil before or after inoculation and incubation. Although protozoa and amoebae were detected in the soils, the numbers were low and did not increase over the incubation period. These results suggest that the antibiotic activity of Jordan's red soils is due to the proliferation of antibiotic-producing bacteria.

scholarly journals Antibacterial activity of ginger extracts and its essential oil on some of pathogenic bacteria

2010 ◽  
Vol 7 (3) ◽  
pp. 1159-1165
Author(s):  
Baghdad Science Journal
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Essential Oil ◽  
Pathogenic Bacteria ◽  
Cold Water ◽  
Water Extract ◽  
Ethanolic Extract ◽  
Hot Water ◽  
Diffusion Method ◽  
Resistant Bacteria

The antimicrobial activity of ginger extracts ( cold-water, hot-water, ethanolic and essential oil ) against some of pathogenic bacteria ( Escherichia coli , Salmonella sp , Klebsiella sp , Serratia marcescens, Vibrio cholerae , Staphylococcus aureus , Streptococcus sp) was investigated using Disc diffusion method , and the results were compared with the antimicrobial activity of 12 antibiotics on the same bacteria . The results showed that the ginger extracts were more effective on gram-positive bacteria than gram-negative . V. cholerae and S. marcescens,were the most resistant bacteria to the extracts used , while highest inhibition was noticed against Streptococcus sp (28 mm) . The ethanolic extract showed the broadest antibacterial activity ( 11 to 28 mm ) , in comparison with moderate activity of essential oil , it was observed that the cold-water extract was more effective on the bacteria than hot-water extract . Ginger ethanolic extract presented higher diameter of inhibition zone for Streptococcus sp than in Ciprofloxacin , Cefotaxime , Cefalotin , Cephalexin and Cephaloridine , also it was found a similarity between the higher inhibition zones of ethanolic extract of ginger and some antibiotics for S. aureus , E. coli , Salmonella sp and Klebsiella sp . V. cholerae and S. marcescens,also highly resistant to antibiotics . Phytochemical analysis of ethanolic extract of ginger revealed the present of glycosides, terpenoids, flavonids and phenolic compounds

scholarly journals Identification of Antimicrobial Peptides from the Microalgae Tetraselmis suecica (Kylin) Butcher and Bactericidal Activity Improvement

Marine Drugs ◽  
2019 ◽  
Vol 17 (8) ◽  
pp. 453 ◽  
Author(s):  
Guzmán ◽  
Wong ◽  
Román ◽  
Cárdenas ◽  
Alvárez ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Bioactive Peptides ◽  
De Novo ◽  
Helical Structure ◽  
Antimicrobial Activities ◽  
Peptide Sequence ◽  
Tetraselmis Suecica ◽  
Defense Strategies ◽  
Key Residues

The outburst of microbial resistance to antibiotics creates the need for new sources of active compounds for the treatment of pathogenic microorganisms. Marine microalgae are of particular interest in this context because they have developed tolerance and defense strategies to resist the exposure to pathogenic bacteria, viruses, and fungi in the aquatic environment. Although antimicrobial activities have been reported for some microalgae, natural algal bioactive peptides have not been described yet. In this work, acid extracts from the microalga Tetraselmis suecica with antibacterial activity were analyzed, and de novo sequences of peptides were determined. Synthetic peptides and their alanine and lysine analogs allowed identifying key residues and increasing their antibacterial activity. Additionally, it was determined that the localization of positive charges within the peptide sequence influences the secondary structure with tendency to form an alpha helical structure.

Edible film based on Vicia faba shell gum, nano silver and Helichrysum arenarium essence

2019 ◽  
Vol 50 (2) ◽  
pp. 280-287 ◽  
Author(s):  
Farzane Jahantigh
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Natural Antioxidants ◽  
Inhibition Zone ◽  
Edible Film ◽  
Composition Analysis ◽  
Disk Diffusion Test ◽  
Content Type ◽  
The Difference

Purpose The inclusion of natural antioxidants and nanoparticles into edible coatings can improve their structure, functionality and applicability in foods. This study aims to determine the antibacterial effect of new nano-composite based on bean pod shell gum (BPSG), silver nanoparticle (SNP) and herbal essential oil (EO). Design/methodology/approach For this purpose, BPSG (4 per cent w/v), SNP (0.5-1 per cent w/v) and Helichrysum arenarium EO (1-2 per cent v/v) were mixed. After preparation the edible film, the antibacterial activity was tested on five food-borne pathogenic bacteria in two categories including two-gram positives and three-gram negatives bacteria. The EO composition was determined by GC–mass spectrometry and the antibacterial activity was tested using disk diffusion test. Findings Results showed that gram-positive bacteria were more susceptible than gram-negative bacteria. Increasing Helichrysum arenarium EO and SNP content increased antimicrobial activity of the edible film based on BPSG, so that the treatment containing 2 per cent v/v Helichrysum arenarium EO and 1 per cent w/v SNP led to the highest inhibition zone (8.1-13.1 mm) compared to treatment containing 1 per cent v/v Helichrysum arenarium EO and 0.5 per cent w/v SNP with inhibition zone range of 5.4-9.9 mm and the difference was statistically significant (p = 0.41). Also, the chemical composition analysis of the EO identified a total of 38 compounds in which a-pinene (32 per cent), 1,8-cineole (16 per cent), α-humulene (15 per cent) and ß-caryophyllene (8 per cent) were the main fractions. Other separated components accounted less than 29 per cent of the oil. Originality/value In general, SNP and Helichrysum arenarium EO improved the functional properties including the antimicrobial activity of the edible film based on BPSG, which increases the potential to be used as active packaging for fresh products.

Inhibition of Food-Related Pathogenic Bacteria by god-Transformed Penicillium nalgiovense Strains

1999 ◽  
Vol 62 (8) ◽  
pp. 940-943 ◽  
Author(s):  
ROLF GEISEN
Keyword(s):  
Antibacterial Activity ◽  
Inhibitory Activity ◽  
Type Strain ◽  
Salmonella Enteritidis ◽  
Pathogenic Bacteria ◽  
Wild Type Strain ◽  
Antibacterial Effect ◽  
Wild Type ◽  
Penicillium Nalgiovense ◽  
And Staphylococcus Aureus

Two strains of Penicillium nalgiovense, which carried the god gene of Aspergillus niger and had increased glucose oxidase (GOD) activity compared with the wild-type strain, were tested for their ability to suppress the growth of certain food-related pathogenic bacteria. In contrast to the wild type, which showed no antibacterial effect when grown in mixed culture with different bacteria, the two tranformed strains were highly antagonistic. The strain that expressed higher amounts of GOD in general had higher inhibitory activity. Both strains showed antibacterial activity against Listeria monocytogenes, Salmonella Enteritidis, and Staphylococcus aureus. The inhibitory activity was dependent on the glucose concentration in the medium. S. aureus was completely inhibited at 1% glucose in the presence of the higher GOD-producing transformant. In contrast, if arabinose was used as a carbon source, no inhibition occurred. If catalase was added to the medium, the inhibitory activity of the transformants was completely inactivated, indicating that the hydrogen peroxide produced was responsible for the antibacterial activity of the transformants.

scholarly journals COMPARATIVE ANALYSIS OF METAL NANOPARTICLES SYNTHESIZED FROM HIBISCUS ROSA SINESIS AND THEIR ANTIBACTERIAL ACTIVITY ESTIMATION AGAINST NINE PATHOGENIC BACTERIA

2017 ◽  
Vol 10 (5) ◽  
pp. 323
Author(s):  
Shruti Tyagi
Keyword(s):  
Antibacterial Activity ◽  
Pathogenic Bacteria ◽  
Au Nanoparticles ◽  
Size Range ◽  
Micrococcus Luteus ◽  
Bacterial Species ◽  
Cost Effective ◽  
Antibacterial Activities ◽  
Agar Disc ◽  
Vis Spectroscopy

Objective: This study demonstates  a simple, cost effective protocol  for biosynthesis of stable silver (Ag) and gold (Au) nanoparticles from Hibiscus Rosa sinesis and their comparison by applying antibacterial activities against nine pathogenic bacterial species.Methods: Silver (Ag) and gold (Au) nanoparticles were biosynthesized from Hibiscus Rosa sinesis were characterized by UV–VIS spectroscopy, FTIR and TEM. The antibacterial activities  of AgNPs  and AuNPs were evaluated against  9 pathogenic bacterial species  Pseudomonas aeroginosa, Bacillus subtilis Micrococcus luteus, Staphylococcus aureus, Staphylococcus epidermidis, Enterobacter aerogens, Escherichia coli, Streptococcus pneumoniae, Aeromonas hydrophila by the agar disc diffusion method.Results: Synthesized AgNPs  were obtained in 13.01 to 28.14 nm size range, while AuNPs were in  6.32 to 18.19 nm size range. The results of Fourier transform infrared spectroscopy (FTIR) spectra indicates  that the AuNPs are bound to amine groups and the AgNPs to carboxylate ion groups. The antibacterial activities  of AgNPs,  the zone of inhibition significantly increased with the  increases of concentrations of AgNPs in all pathogenic bacterial species  except  in the case of S. epidermidis at 50%, S. aerogenes and A. hydrophila at 70%, while in case of AuNPs antibacterial activity  was displayed  only against B. subtilis at 20% and 100% concentration.Conclusion: This study suggests that AgNPs exhibits outstanding antibacterial activity against pathogenic bacteria as compared to AuNPs synthesized from Hibiscus Rosa sinensis leaf extract and insights to their potential applicability as an alternative antibacterial  agent in microbial and human health system to reduce the resistance ability of pathogenic bacteria. Keywords: silver nanoparticles; gold  nanoparticles; UV–VIS spectroscopy; FTIR; TEM; antibacterial activities.  

Berberine sulfate: antimicrobial activity, bioassay, and mode of action

1969 ◽  
Vol 15 (9) ◽  
pp. 1067-1076 ◽  
Author(s):  
A. H. Amin ◽  
T. V. Subbaiah ◽  
K. M. Abbasi
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Antibacterial Activity ◽  
Deoxyribonucleic Acid ◽  
Test Organism ◽  
Inoculum Size ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Rna And Protein Synthesis ◽  
And Staphylococcus Aureus

Berberine sulfate was shown to possess antimicrobial activity against a wide variety of microorganisms including Gram-positive and Gram-negative bacteria, fungi, and protozoa. The antibacterial activity against Vibrio cholerae and Staphylococcus aureus was dependent on the inoculum size of the test organism and pH of the medium. A method of microbiological assay sensitive to 5–10 μg/ml of the drug was developed. The drug was shown to exert a more rapid antibacterial activity than chloramphenicol and tetracycline on V. cholerae, the K values being 2.4 ×10−2 sec−1, 7.8 × 10−3 sec−1, and 5.2 × 10−3 sec−1 respectively. Berberine sulfate was shown to be bacteriocidal to V. cholerae and bacteriostatic to S. aureus, at concentrations of 35 and 50 μg/ml. In both these organisms concentrations of 35 and 50 μg/ml of the drug inhibited ribonucleic acid (RNA) and protein synthesis almost immediately after the addition of the drug. There was little effect on deoxyribonucleic acid (DNA) synthesis at these concentrations.

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