scholarly journals Dermaseptins fromPhyllomedusa oreadesandPhyllomedusa distincta

2002 ◽  
Vol 277 (51) ◽  
pp. 49332-49340 ◽  
Author(s):  
Guilherme D. Brand ◽  
José Roberto S. A. Leite ◽  
Luciano P. Silva ◽  
Sérgio Albuquerque ◽  
Maura V. Prates ◽  
...  

Amphibian skin secretions are known as a rich source of biologically active molecules, most of which are alkaloids, biogenic amines, and peptides. Dermaseptins are a class of antimicrobial peptides present in tree frogs of thePhyllomedusagenus. They are cationic molecules of 28–34 residues that permeabilize the membrane of Gram-positive and Gram-negative bacteria, yeasts, and filamentous fungi, showing little or no hemolytic activity. This work reports the isolation, molecular mass analysis, primary structure determination, biological activities, and potential therapeutic applications of an antimicrobial peptide found in the skin secretion ofPhyllomedusa oreades,which is a newly described amphibian species endemic of the Brazilian savanna. DS 01 is a 29-residue-long peptide with a molecular mass of 2793.39 Da showing antibacterial properties against Gram-positive and Gram-negative bacteria in the range of 3–25 μm. Anti-protozoan activity was investigated usingT. cruziin its trypomatigote and epimastigote forms cultivated in both cell culture and blood media. Within 2 h after incubation with DS 01 at a final concentration of ∼6 μm, no protozoan cells were detected. Two synthetic dermaseptins, described previously by our group and named dermadistinctins K and L (DD K and DD L), also had their anti-Trypanosoma cruziactivity investigated and demonstrated similar properties. Toxicity of DS 01 to mouse erythrocytes and white blood cells was evaluated by means of atomic force microscopy and flow cytometry. No morphological alterations were observed at a lytic concentration of DS 01, suggesting its therapeutic value especially as an anti-T. cruziagent to prevent infections during blood transfusion.

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Eti Nurwening Sholikhah ◽  
Maulina Diah ◽  
Mustofa ◽  
Masriani ◽  
Susi Iravati ◽  
...  

Pycnarrhena cauliflora (Miers.) Diels., local name sengkubak, is one of indigenous plants from West Kalimantan that has been used as natural flavor. Pycnorrhena cauliflora is one of species of Menispermaceae family which is rich in bisbenzylisoquinoline alkaloids. This alkaloids are known to have various biological activities including antiprotozoal, antiplasmodial, antifungal and antibacterial activities. This study aimed to investigate antimicrobial activity of  the P. cauliflora (Miers.) Diels. methanolic extracts against gram-positive and gram-negative bacteria. The methanolic extract of P. cauliflora (Miers.) Diels., root, leaf and stem were prepared by maceration. The disk-diffusion method was then used to determine the antimicrobial activity of the extracts against Streptococcus pyogenes, S. mutants, Staphylococcus aureus, S. epidermidis, Salmonella typhi, Shigella flexneri, Pseudomonas aeruginosa and Escherichia coli after 18-24 h incubation at 37 oC. Amoxicillin was used as positive control for gram-positive bacteria and ciprofloxacin was used as gram-negative bacteria. The inhibition zones were then measured in mm. Analysis were conducted in duplicates. The results showed in general the methanolic extracts of P. cauliflora (Miers.) Diels. root (inhibition zone diameter= 10-23 mm) were more active than that leaf (0-15 mm) and stem (0-17 mm) extracts against gram-positive bacteria. The zone inhibition diameter of amoxicillin as positive control was 8-42 mm. In addition, the methanolic extracts of P. cauliflora (Miers.) Diels. root (12-17 mm) were also more active than that leaf (0-12 mm) and stem (0-12 mm) extracts against gram-negative bacteria. The zone inhibition diameter of ciprofloxacin as positive control was 33-36 mm. In conclusion, the methanolic extract of P. caulifloria (Miers.) Diels. root is the most extract active against both gram-positive and gram-negative bacteria. Further study will be focused to isolate active compounds in the methanolic extract of the root.


2021 ◽  
Vol 13 (1) ◽  
pp. 106-112
Author(s):  
Sri Kasmiyati ◽  
Elizabeth Betty Elok Kristiani ◽  
Maria Marina Herawati ◽  
Andreas Binar Aji Sukmana

The medicinal plant-derived bioactive compounds have a potential for many biological activities, including antimicrobial activity. Artemisia cina is a medicinal plant from the Compositae family with the potential of having antitumor, antifungal, and antibacterial activity. This study aimed to determine the antibacterial activity and the flavonoid content of A. Cina’s ethyl acetate extract. Plants samples were extracted by ethyl acetate maceration method. Antibacterial activity was tested against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) by a disk diffusion method using 25, 50, and 100 mg/l extract concentrations. The flavonoid contents (quercetin and kaempferol) were measured using High-Performance Liquid Chromatography. The extracts of diploid and polyploid A. cina displayed some antibacterial activity, with the Gram-negative bacteria being more resistant than the Gram-positive counterpart. However, no significant difference was observed between the diploid and polyploid extracts. As for the flavonoid content, the highest quercetin content (0.5501 mg/ml) was found in the polyploid A. cina (J), while the highest kaempferol content (0.5818 mg/ml) was observed in the diploid A. cina (KJT). Although A. cina is widely grown in Indonesia, compared to other Artemisia species, A. cina has not been widely studied, especially its antibacterial  potential and in related to its flavonoid content and the use of ethyl acetate as the extraction solvent.  This study reveals the potential of A. cina as a natural antibacterial agent. 


2018 ◽  
Vol 6 (2) ◽  
pp. 110-114
Author(s):  
Bimala Subba

Phytochemical and biological activities of methanolic extract of Taxus wallichiana Zucc. (Leaf, stem) were carried out. The brine shrimp bioassay showed T. wallichiana is pharmacologically active. The antibacterial potential was studied against one gram positive bacteria (Staphylococcus aureus) and one gram negative bacteria (Escherichia Coli) using Agar Well Diffusion Method. Stem of T. wallichiana showed significant zone of inhibition against gram positive bacteria while the leaf of T. wallichiana did not show significant zone of inhibition against both gram positive and gram negative bacteria. Antioxidant activity was evaluated by 2, 2-diphenyl-1-picryl hydrazyl (DPPH) free radical scavenging activity and FRAP assay. Both assay showed that T. wallichiana leaves has high antioxidant activities.Int. J. Appl. Sci. Biotechnol. Vol 6(2): 110-114


2016 ◽  
Vol 34 (2) ◽  
pp. 35
Author(s):  
Prayna P. P. Maharaj ◽  
Riteshma Devi ◽  
Surendra Prasad

Fiji is highly populated with plants containing essential oils (EO). The essential oils extracted from the leaves of the selected Fijian leafy plants were screened against two Gram-negative bacteria (Salmonella typhimurium, Pseudomonas aeruginosa) and three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis). The agar diffusion method was used to examine the antimicrobial activities of the extracted EO. All the EO tested showed antibacterial properties against one or more strains while none of the EO was active against Pseudomonas aeruginosa. Viburnum lantana (Wayfaring tree), Annona muricata (Soursop), Coleus amboinicus (Spanish thyme) and Cinnamomum zeylancium (Cinnamon) showed good inhibition against both Gram-positive and Gram-negative bacteria and proved as worthy source of antimicrobial agent. These findings will help the Pacific population to use the studied plants leaves as antimicrobial agent.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
José Carlos Vilar Junior ◽  
Daylin Rubio Ribeaux ◽  
Carlos Alberto Alves da Silva ◽  
Galba Maria De Campos-Takaki

This research aims to study the production of chitosan from shrimp shell (Litopenaeus vannamei) of waste origin using two chemical methodologies involving demineralization, deproteinization, and the degree of deacetylation. The evaluation of the quality of chitosan from waste shrimp shells includes parameters for the yield, physical chemistry characteristics by infrared spectroscopy (FT-IR), the degree of deacetylation, and antibacterial activity. The results showed (by Method 1) extraction yields for chitin of 33% and for chitosan of 49% and a 76% degree of deacetylation. Chitosan obtained by Method 2 was more efficient: chitin (36%) and chitosan (63%), with a high degree of deacetylation (81.7%). The antibacterial activity was tested against Gram-negative bacteria (Stenotrophomonas maltophiliaandEnterobacter cloacae) and Gram-positiveBacillus subtilisand the Minimum Inhibitory Concentrations (MIC) and the Minimum Bactericidal Concentration (MBC) were determined. Method 2 showed that extracted chitosan has good antimicrobial potential against Gram-positive and Gram-negative bacteria and that the process is viable.


2011 ◽  
Vol 14 (1) ◽  
pp. 85-89 ◽  
Author(s):  
Wally J. Bartfay ◽  
Emma Bartfay ◽  
Julia Green Johnson

The emergence of new pathogens and the increase in the number of multidrug-resistant strains in well-established pathogens during the past decade represent a growing public health concern globally. With the current lack of research and development of new antibiotics by large pharmaceutical companies due to poor financial returns, new alternatives need to be explored including natural herbal or plant-based extracts with reported antibacterial properties. Willow herb ( Epilobium angustifolium) preparations have been used in traditional aboriginal and folk medicine preparations externally as an antiphlogistic to treat prostate and gastrointestinal disorders and as an antiseptic to treat infected wounds. The authors hypothesized that a whole plant extract of willow herb would exhibit antimicrobial properties on a variety of both Gram-positive and gram-negative bacteria in culture. The authors found that, in comparison to growth controls, willow herb extract significantly inhibited the growth of Micrococcus luteus ( p < .01), Staphylococcus aureus ( p < .05), Escherichia coli ( p < .001), and Pseudomonas aeruginosa ( p < .001). They also found that willow herb extract inhibited the growth of bacteria in culture more effectively than vancomycin ( p < .05) or tetracycline ( p < .004). These results provide preliminary support for the traditional folkloric claim that the plant willow herb possesses antibacterial properties against a variety of gram-positive and gram-negative bacteria. Given that whole plant extract was utilized for this study, further investigations are warranted to determine which specific part of the plant (i.e., leaves, stem, roots, and flowers) possess the antibacterial properties.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Zahra Moodi ◽  
Ghodsieh Bagherzade ◽  
Janny Peters

Quercetin (3,3′,4′,5,7-pentahydroxyflavone) is one of the dietary flavonoids, distributed in medicinal plants, vegetables, and fruits. Quercetin has the ability to bind with several metal ions to increase its biological activities. In the last two decades, quercetin has attracted considerable attention due to the biological and pharmaceutical activities such as antioxidant, antibacterial, and anticancer. In the present study, quercetin and ethanolamine were used for the synthesis Schiff base complex, which was characterized by IR, 1H NMR, and 13C NMR spectroscopy. The Schiff base has been employed as a ligand for the synthesis of novel nanoscale Cu (II) complex. The product was characterized by FT-IR spectroscopy, FESEM, and XRD. Significantly, the product showed remarkable catalytic activity towards the oxidation of primary and secondary alcohols. The antibacterial activity of the final product was assessed against Staphylococcus aureus (Gram‐positive) and Escherichia coli (Gram‐negative) bacteria using an inhibition zone test. The synthesized nanoscale Cu (II) complex exhibited a strong antibacterial activity against both Gram-positive and Gram-negative bacteria.


2018 ◽  
Vol 22 (2) ◽  
pp. 140-147 ◽  
Author(s):  
Bimala Subba ◽  
Susila Thapa

Phytochemical and biological activities of methanolic extract of seven plants viz. Scindapsus officinalis Schott. , Lepisorus loriformis, Nicotiana tabacum L., Clematis buchananiana DC., Astilbe rivularis D. Don, Potentilla fulgens Wall. ex Hook and Taxus wallichiana Zucc. were carried out. The brine shrimp bioassay showed that N. tabacum, A. rivularis, and P. fulgens were pharmacologically active. The antibacterial potential was studied against Staphylococcus aureus (gram positive bacteria) and Escherichia coli (gram negative bacteria) using Agar Well Diffusion Method. Roots of P. fulgens showed inhibition against gram positive bacteria while the rhizome of A. rivularis showed inhibition against both gram positive and gram negative bacteria. Antioxidant activity was evaluated by 2, 2-diphenyl-1-picryl hydrazyl (DPPH) free radical scavenging activity and ferric reducing antioxidant power FRAP assay. Both assays showed that P. fulgens has high antioxidant activities with (IC50 =15.57 ± 3.6) lower than standard ascorbic acid.  Journal of Institute of Science and TechnologyVolume 22, Issue 2, January 2018, Page: 140-147


BIBECHANA ◽  
2020 ◽  
Vol 17 ◽  
pp. 104-109
Author(s):  
Shanta Pokhrel ◽  
Kalpana Chaulagain

Phytochemical and biological activities of methanolic and hexane extract of Acorus calamus rhizome were carried out. Phytochemical analysis showed the presence of flavonoid, glycoside, saponin, resin and carbohydrates which are responsible for the antibacterial activities. The antibacterial potential was studied against Staphylococcus aureus (gram positive bacteria) and Escherichia coli, Salmonella typhi (gram negative bacteria) using Agar Well Diffusion Method. The activity was shown by both methanolic and hexane extract of Acorus calamus rhizome against both Gram positive and Gram negative bacteria. Antioxidant activity of methanolic extract was evaluated by 2, 2-diphenyl-1-picryl hydrazyl (DPPH) free radical scavenging activity showed potent antioxidant activities with IC50 value 3.74 μg/mL slightly higher than standard ascorbic acid (IC50 = 3.56 μg/mL). BIBECHANA 17 (2020) 104-109


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shooq Yousef Al-blooshi ◽  
Mustafa Amir Abdul Latif ◽  
Nour K. Sabaneh ◽  
Michael Mgaogao ◽  
Ashfaque Hossain

Abstract Objective Although many bacterial culture media are available commercially, there is a continuous effort to develop better selective media for bacteria, which cannot be grown on existing media. While exploring antibacterial properties of clove, we observed that it has the potential to selectively inhibit growth of certain types of bacteria. This led us to do the experiments, which resulted in developing a new media which selectively allowed the growth of only Gram-negative bacteria, while inhibiting the Gram-positive bacteria. Results Mueller Hinton Agar (MHA) was used as the base media and was modified to develop MHA-C15 (MHA containing 15% volume/volume water extract of clove). Gram-negative bacterial pathogens Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium and Pseudomonas aeruginosa grew on MHA-C15. However, none of the major Gram-positive bacterial pathogens such as Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus mutans, Bacillus spp. and Enterococcus spp. grew on it. Taken together, these findings show that MHA-C15 is a newly developed selective media for culture of Gram-negative bacteria.


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