scholarly journals New Antibacterial Bagremycins F and G from the Marine-Derived Streptomyces sp. ZZ745

Marine Drugs ◽  
2018 ◽  
Vol 16 (9) ◽  
pp. 330 ◽  
Author(s):  
Di Zhang ◽  
Chenyan Shu ◽  
Xiaoyuan Lian ◽  
Zhizhen Zhang

As part of our research to discover novel bioactive natural products from marine microorganisms, five bagremycin analogues, including the previously unreported bagremycins F (1) and G (2), were isolated from a marine actinomycete Streptomyces sp. ZZ745. The structures of these compounds were determined by means of NMR spectroscopic analysis, HRESIMS data, and optical rotation. Both bagremycins F (1) and G (2) showed antibacterial activity against Escherichia coli, with MIC values of 41.8 and 61.7 μM, respectively.

Author(s):  
Gouse Basha Sheik ◽  
Muazzam Sheriff Maqbul ◽  
Gokul Shankar S. ◽  
Ranjith M S

Objective: To isolate and characterize novel actinomycetes and to evaluate their antibacterial activity against drug-resistant pathogenic bacteriaMethods: In the present study, 19 soil samples were collected from different localities of Ad-Dawadmi, Saudi Arabia. Actinomycetes were isolated from these samples using serial dilution and plating method on Actinomycetes isolation agar supplemented with nalidixic acid and actidione to inhibit bacteria and fungi. Crude extracts of potential actinomycetes were produced by submerged fermentation. The antimicrobial activity of crude extracts of actinomycetes was tested against different bacteria using the agar well diffusion method. Characterization of the isolates was done by morphological, physiological and biochemical methods.Results: A total of 9 (47%) isolates of actinomycetes were isolated from 19 different soil samples tested. Among them, 4 (44%) isolates confirmed as Streptomyces sp. showed potential antimicrobial activity against one or more test organisms. Crude extracts were made from these 4 actinomycetes isolates(DOM1, DOM3, DP3, DP4)and tested for their antibacterial activities against 4 different clinical bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus). Crude extract from DP3 isolate showed highest antibacterial activity against all the four test organisms (28 mm, 21 mm, 20 mm and 18 mm) respectively and DP4 showed lowest antibacterial activity against all the four test organisms (14 mm, 12 mm, 0 mm, 6 mm) respectively. The highest zone of inhibition was shown by DP3 against Staphylococcus aureus (28 mm) and Escherichia coli was resistant for DP4. Most of the Inhibition zones produced by crude extracts showed significant differences when compared with control, tested against test organisms (P<0.05). Inhibition zones produced by DP3 and DOM1 against Staphylococcus aureus were 28 mm and 23 mm, respectively which were strong active when compared with control Ciprofloxacin (18 mm).Conclusion: Further studies for purification of bioactive metabolites and molecular characterization analysis of isolated Streptomyces sp. are in progress which would be helpful in discovering novel compounds of commercial value.


2018 ◽  
Vol 85 (0) ◽  
Author(s):  
Gabriela Silva Moura ◽  
Ivan Júnior de Oliveira ◽  
Lisandro Tomas da Silva Bonome ◽  
Gilmar Franzener

ABSTRACT: Natural products extracted from plants have always played an important role in the discovery of bioactive substances. This work carried out a review of the literature on the bioactive activities of Eugenia uniflora L. (Surinam cherries), as a potential plant in the various uses, be it medicinal, antimicrobial, antioxidant, insecticide and protective. In the literature, studies were found to confirm the antibacterial activity of E. uniflora leaves extract on Streptococcus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The presence of antioxidant compounds as total phenolics, such as anthocyanins and flavonoids, induction in the protection of plants by phytoalexins, as well as insecticidal and anthelmintic effects by the use of the extract of the E. uniflora tree. Although these different potential biotics of E. uniflora have already been reported, further studies are still needed on the use of natural products extracted from E. uniflora for employment for different purposes.


2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Mengxuan Chen ◽  
Weiyun Chai ◽  
Tengfei Song ◽  
Mingzhu Ma ◽  
Xiao-Yuan Lian ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Fernando G. Figueredo ◽  
Emerson O. Ferreira ◽  
Bruno F. F. Lucena ◽  
Cícero M. G. Torres ◽  
Daniel L. Lucetti ◽  
...  

The aim of this study was to verify the possible interactions between ethanol extracts ofAmburana cearensisA. C. Smith andAnadenanthera macrocarpa(Benth.) Brenan, combined with six antimicrobial drugs against multiresistant strains ofStaphylococcus aureusandEscherichia coliisolated from humans. The antibacterial activity of the extracts was determined using the minimum inhibitory concentration (MIC). The microdilution assay was performed to verify the interactions between the natural products and the antibiotics using a subinhibitory concentration. The activity of amikacin associated with the extract ofAnadenanthera macrocarpaagainst EC 27 was enhanced, demonstrating an MIC reduction from 128 to 4 μg/mL. Among theβ-lactams, no potentiation on its activity was observed, with exception to the antagonism of the natural products with ampicillin againstS. aureus358.


2003 ◽  
Vol 75 (2-3) ◽  
pp. 343-352 ◽  
Author(s):  
P. Proksch ◽  
R. Ebel ◽  
R. A. Edrada ◽  
P. Schupp ◽  
W. H. Lin ◽  
...  

This review article presents our group's recent research findings with regard to bioactive natural products from marine sponges and tunicates, as well as from sponge derived fungi. The organisms discussed originate in the Indopacific region, which has an exceptionally rich marine biodiversity. Major topics that are covered in our review include the chemical ecology of sponges, focusing on defense against fishes, as well as the isolation and identification of new bioactive constituents from sponges and tunicates. Sponge derived fungi are introduced as an emerging source for new bioactive metabolites, reflecting the currently growing interest in natural products from marine microorganisms.


2018 ◽  
Vol 12 (02.1) ◽  
pp. 3S
Author(s):  
Antoine Abou Fayad ◽  
Dana Itani ◽  
Mariam Miari ◽  
Arax Tanelian ◽  
Sereen Iweir ◽  
...  

Introduction: Antimicrobial resistance (AMR) is emerging at an alarming rate as mortality due to resistant pathogens could rise to 10 million per year by 2050. Since AMR is against all clinically utilized antibiotics, finding novel antimicrobials with unexploited targets remains the main goal worldwide.  Soil microorganisms produce natural products as a significant number of drugs in clinical use are derived from these metabolites. Actinomycetes and Myxobacteria are soil dwelling microorganisms that produce secondary metabolites to be screened for antibacterial activity. More than 80% of clinically utilized antibiotics are either natural products or natural product-derived molecules such as vancomycin, teicoplanin, daptomycin, and tetracycline. This study aims to isolate and identify novel antimicrobials from Actinomycetes and Myxobacteria. Methodology: Soil samples were collected from several areas in Lebanon. Samples were serially diluted for Actinomycetes isolation and boiled for Myxobacteria extraction, then plated on suitable media. Colonies obtained were purified and subjected to genomic DNA extraction then 16s rRNA analysis. Novel isolates were tested for their antimicrobial activity against Gram-positive Bacillus subtilis (ATCC 6051), Staphylococcus aureus (ATCC 29213, Newman, N315), Enterococcus faecalis (ATCC 19433), and Enterococcus faecium (DSMZ 17050), and Gram-negative Escherichia coli (ATCC 9637), Klebsiella pneumoniae (DSMZ), Pseudomonas aeruginosa (ATCC 27853, MEXAB), and Acinetobacter baumannii (ATCC 15308). Results: Strain isolation and cultivation yielded a number of novel isolates whose extracts demonstrated strong antibacterial activity against pathogens including MRSA, VRE, and Escherichia coli (ATCC 9637). Conclusion: Our efforts now focus on purifying these compounds, elucidate their structures and study their mode of action.


2021 ◽  
Author(s):  
◽  
Hadeel Alhazmi

This thesis describes phytochemical studies on the methanolic extract of Curcuma longa; a medicinally important plant used as indigenous medicine for the treatment of wounds in South Asian and African countries. The crude extract displayed antibacterial activity against the Gram-positive bacterium, Staphylococcus aureus, but was inactive against Gram-positive bacterium Streptococcus agalactiae. This extract also did not show antibacterial activity against Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa. Based on the observed antibacterial activity, it was decided to carry out phytochemical investigation of crude methanolic extract of C. longa to isolate and characterize natural products and evaluate them for antimicrobial activity. These efforts resulted in the identification of three known natural products: curcumin (39) sclareolide (40) and atalantoflavone (41). Structures of these compounds were established with the aid of NMR spectroscopic studies. Compounds (40) and (41) have been isolated for the first time from this plant. Compounds (39-41) were found to be inactive against the Gram-positive bacterium, Staphylococcus aureus, and Gram-negative bacterium, Escherichia coli.


Marine Drugs ◽  
2019 ◽  
Vol 17 (10) ◽  
pp. 559 ◽  
Author(s):  
Fadia S. Youssef ◽  
Mohamed L. Ashour ◽  
Abdel Nasser B. Singab ◽  
Michael Wink

Fungal marine microorganisms are a valuable source of bioactive natural products. Fungal secondary metabolites mainly comprise alkaloids, terpenoids, peptides, polyketides, steroids, and lactones. Proteins and peptides from marine fungi show minimal human toxicity and less adverse effects comparable to synthetic drugs. This review summarizes the chemistry and the biological activities of peptides that were isolated and structurally elucidated from marine fungi. Relevant fungal genera including Acremonium, Ascotricha, Aspergillus, Asteromyces, Ceratodictyon, Clonostachys, Emericella, Exserohilum, Microsporum, Metarrhizium, Penicillium, Scytalidium, Simplicillium, Stachylidium, Talaromyces, Trichoderma, as well as Zygosporium were extensively reviewed. About 131 peptides were reported from these 17 genera and their structures were unambiguously determined using 1D and 2D NMR (one and two dimensional nuclear magnetic resonance) techniques in addition to HRMS (high resolution mass spectrometry). Marfey and Mosher reactions were used to confirm the identity of these compounds. About 53% of the isolated peptides exhibited cytotoxic, antimicrobial, and antiviral activity, meanwhile, few of them showed antidiabetic, lipid lowering, and anti-inflammatory activity. However 47% of the isolated peptides showed no activity with respect to the examined biological activity and thus required further in depth biological assessment. In conclusion, when searching for bioactive natural products, it is worth exploring more peptides of fungal origin and assessing their biological activities.


Author(s):  
Muhammad Alfid Kurnianto ◽  
Harsi Dewantari Kusumaningrum ◽  
Hanifah Nuryani Lioe

Saluran pencernaan (terutama usus) ikan perairan estuaria merupakan salah satu ceruk lingkungan potensial Actinobacteria yang belum tereksplorasi. Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi karakteristik morfologi Actinobacteria asal ikan bandeng (Chanos chanos) dan belanak (Mugil cephalus) serta mengevaluasi aktivitas antimikroba yang dihasilkannya. Penelitian ini diawali dengan mengambil usus ikan, kemudian digesta usus secara perlahan dipisahkan untuk dieksplorasi keberadaan Actinobacteria dengan menggunakan media isolasi selektif. Isolat yang diperoleh dikarakterisasi berdasarkan ciri makroskopik dan mikroskopik, serta dilakukan penapisan antibakteri awal menggunakan metode double-layer diffusion. Isolat dengan zona penghambatan terbaik dipilih untuk dilakukan produksi dan ekstraksi senyawa antibakteri, serta uji aktivitas antibakteri dengan metode difusi cakram terhadap bakteri uji Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa dan Escherichia coli. Sebanyak 44 isolat Actinobacteria telah diisolasi dari digesta usus ikan bandeng (Chanos chanos) dan belanak (Mugil cephalus) menggunakan media strach casein dan actinomycete isolation agar. Sebagian besar isolat yang diperoleh menunjukkan karakteristik morfologi genus Streptomyces sp., seperti koloni memiliki tekstur menyerupai serbuk, bertepung dan kasar, memiliki aerial miselium berwarna putih dan substrat miselium berwarna krim susu, serta memiliki bentuk rantai spora rectus-flexibilis. Proses penapisan antibakteri isolat Actinobacteria menunjukkan 22 isolat memiliki indeks penghambatan terhadap sedikitnya satu bakteri uji, dengan aktivitas terbaik ditunjukkan oleh isolat A-SCA-11. Uji antibakteri terhadap ekstrak kasar isolat A-SCA-11 menunjukkan aktivitas antibakteri berspektrum luas yang mampu menghambat seluruh bakteri uji dengan zona hambat tertinggi pada P. aeruginosa.  AbstractThe gut of estuary fish is one of the potential novel niches of Actinobacteria that has not yet been explored. This study aimed to isolate and identify the morphological characteristics of Actinobacteria from milkfish (Chanos chanos) and blue-spot mullet fish (Mugil cephalus) and to evaluate the antibacterial activity produced. This research was started by taking the fish gut, and then the digesta were slowly separated to explore the presence of Actinobacteria using selective isolation media. The isolates obtained were characterized by macroscopic and microscopic characteristics, and antibacterial preliminary screening of isolates was performed using a double-layer diffusion method. The isolates with the best inhibition zone were selected for production and extraction of antibacterial compounds, and antibacterial activity tests using the disk-diffusion method against the test bacteria Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, and Escherichia coli. A total of 44 isolates of Actinobacteria have been isolated from the gut of fish using starch casein and actinomycete isolation agar. Most isolates showed morphological characteristics of the genus Streptomyces sp., such as colonies with a tough or powdery texture, antibacterial have white aerial mycelium and milk-cream substrate mycelium, and rectus-flexibilis spore chain. The antibacterial preliminary screening of Actinobacteria isolates showed 22 isolates had inhibitory index against at least one test bacterium, with the best activity indicated by A-SCA-11. Antibacterial test of A-SCA-11 crude extract showed broad-spectrum antibacterial activity that was able to inhibit all test bacteria with the highest inhibitory zone on P. aeruginosa.


Author(s):  
Nguyễn Thị Thủy Tiên ◽  
Lê Thị Thu Hiền ◽  
Trần Thị Lệ Ngân ◽  
Trần Văn Trung ◽  
Nguyễn Thị Thúc ◽  
...  

Streptomyces là những vi sinh vật có khả năng sinh tổng hợp các chất kháng sinh. Nghiên cứu này nhằm sàng lọc và chọn chủng có khả năng kháng khuẩn cao nhất từ 59 chủng Streptomyces có nguồn gốc từ đất đã được cung cấp dựa trên phương pháp cấy vạch vuông góc đối với 5 vi khuẩn gây bệnh chỉ thị, bao gồm Bacillus cereus, Escherichia coli, Salmonella typhi, Staphylococcus aureus và Pseudomonas aeruginosa. Mười lăm chủng thể hiện hoạt tính kháng khuẩn ở các mức độ khác nhau, các chủng còn lại không thể hiện khả năng kháng. Chủng có khả năng kháng khuẩn cao nhất là HĐM3.2, kháng 4/5 vi khuẩn chỉ thị đã sử dụng, gồm B. cerius, S. aureus, S. typhi và E. coli với kích thước vùng kháng đạt 9,5, 10,5, 16,5 và 14,5 mm. Chủng HĐM3.2 được xác định là chủng Streptomyces sp. dựa trên cây phát sinh loài đã xây dựng của trình tự gene 16S rRNA. Điều kiện nuôi cấy để chủng HĐM3.2 thể hiện hoạt tính kháng khuẩn cao nhất đã được khảo sát dựa trên phương pháp khuếch tán qua giếng thạch. Môi trường International Streptomyces Project 2 có pH 8, nhiệt độ nuôi cấy 28oC là điều kiện thích hợp để chủng Streptomyces sp. HĐM3.2 tạo ra vùng ức chế các loại vi khuẩn B. cereus, E. coli, S. typhi, S. aureus cao nhất. ABSTRACT Streptomyces is the microorganism that has capable of producing antibiotics. The current study aimed to screen and to select a strain that had the highest antibacterial activity from 59 available soil-derived Streptomyces strains based on the perpendicular culture method on 5 indicator pathogenic bacteria, including Bacillus cereus, Escherichia coli, Salmonella typhi, Staphylococcus aureus và Pseudomonas aeruginosa. Fourteen strains exhibited their antibacterial activity at various levels, the remaining did not have that activity. The strain that had the highest antibacterial ability was HĐM3.2 against 4/5 indicator microorganisms, including B. cerius, S. aureus, S. typhi and E. coli with inhibitory areas were 9.5, 10.5, 16.5, and 14.5 mm respectively. Strain HĐM3.2 was identified as strain Streptomyces sp. based on a phylogenetic tree built on the 16S rRNA gene sequences. Suitable conditions that made the strain HĐM3.2 showed the highest antibacterial activity were investigated based on agar well diffusion assay. The medium of International Streptomyces Project 2 with pH 8, the ambient temperature at 28oC were suitable conditions for Streptomyces sp. HĐM3.2 produced the highest inhibitory areas against B. cereus, E. coli, S. typhi, S. aureus.  


Sign in / Sign up

Export Citation Format

Share Document