Screening Of Actinomycetes Research Articles

Screening of actinomycetes from Ninh Thuan and Binh Thuan sea for antimicrobial producers

The sea is a unique ecosystem for finding secondary metabolites from marine microorganisms. Many compounds produced by marine microorganisms with antibacterial activity have been applied in life. Furthermore, microorganisms are renewable raw materials and media for drug production, thus crucial for sustainable development in our life. In this study, we screened for antibacterial activity of microbial strains isolated from tern samples from Ninh Thuan and Binh Thuan seas. The antibacterial activity of the marine microbial crude extracts was performed by the Bioassay method in a 96-well tray. The minimum inhibitory concentration (MIC) test results showed that from 86 strains of microorganisms isolated from the waters of Ninh Thuan and Binh Thuan, 68 strains were able to inhibit the growth of 1 to 6 strains of the tested microorganisms, and 27 over 86 strains had antibacterial activity against at least three strains of microorganisms tested. In which strains G631, G756, G769, and G778 inhibited 4 to 6 tested microorganisms with MIC values equal to or lower than positive controls. Morphological characteristics and molecular biological analysis identified the four most active strains. The results showed that all four strains were actinomycetes.

CHARACTERIZATION, IDENTIFICATION AND OPTIMIZATION OF CHITINOLYTIC RARE ACTINOMYCETES ISOLATED FROM SINAI SOIL, EGYPT

Actinomycetes are highly economic and biotechnologically useful prokaryotes able to produce wide range of bioactive secondary metabolites such as antibiotics and enzymes. The present study, aimed to isolate and screen actinomycetes from various soil samples collected from different regions of Saini, Egypt for chitinase production. In instantaneous isolation and screening of actinomycetes from Sixty-one soil samples, only eight isolates were found to have the capability to produce chitinase on colloidal media. Actinomycete strain A13 exhibit highest chitinase production while other strain shown poor production as compared to an index of relative enzyme activity. The most potent chitinolytic actinomycete isolate No. A13 was selected for further studies concerning their identification. Morphological, physiological, and phylogenetic analysis (16S rRNA). In addition to biochemical studies and culture characteristics as well as the chemical analysis of the cell wall, were carried out for the isolate under study. Based on the phenotypic and genotypic accumulated characteristics of the most potent chitinolytic actinomycetes isolate and consulting the recommended International Key’s of Bergey’s Manual for identification of actinomycetes, it was found that this isolate matched with Amycolatopsis orientalis by 97% with some differences and was given the name Amycolatopsis orientalis A13 sp. nova. The results revealed that the chitinase produced by Amycolatopsis orientalis A13 sp. nova can be optimized to produce the highest yield of chitinase and used as biocontrol agent.

Screening of Actinomycetes from Soil for Antibacterial Activity

Actinomycetes are Gram positive, free living saprophytes which are distributed in soil as one of the major populations and are primary source of antibiotics. This study was carried out with a quest to isolate actinomycetes from soil samples of different places and assess their antibacterial activity. Isolation of actinomycetes was carried out by serial dilution of soil sample followed by spread plate method. The antimicrobial extract was extracted using ethyl acetate. Assessment of antimicrobial activity was performed by using Agar cup plate assay against test organisms (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Salmonella paratyphi, Bacillus subtilis, Staphylococcus aureus). Antibacterial activity was tested against Methicillin Sensitive Staphylococcus aureus and Methicillin Resistant Staphylococcus aureus in the isolates having effective inhibitory activity against Staphylococcus aureus. From 15 soil samples of 12 different locations, 121 actinomycetes isolates were isolated. Among them, 58 (47.9%) isolates were inhibitory against at least 1 test organism in primary screening, of which 22 isolates effective against more than 1 test organism was chosen for secondary screening. Out of them, 8 were inhibitory against 2 test organisms while 14 were inhibitory against 3 test organisms. Staphylococcus aureus was found to be the most susceptible test organism with its susceptibility against 12 actinomycetes isolates. Among 12 isolates effective against Staphylococcus aureus, 10 were found to have an inhibitory effect against Methicillin Susceptible Staphylococcus aureus while 6 were found to have inhibitory effect against Methicillin Resistant Staphylococcus aureus strain. The findings of this study highlight the inhibitory potential of actinomycetes and the need for further investigation for obtaining novel antimicrobial agents from actinomycetes from various unexplored areas.

Study of Antimicrobial Activity of Actinomycetes Isolates from Non-Medicinal Plants Produced Soil & Soil Surrounding Medicinal Plants in Junagadh, India

Isolation and screening of actinomycetes and compare its antimicrobial activity from non-medicinal plant produced soil with soil surrounding medicinal plant. In this study total 22 soil samples collected in two sets one from soil surrounding medicinal plant area of Junagadh and other not nearby medicinal plant of same region. Primary screening of isolate done using cross streak method with 8 test pathogens. Secondary screening of most potent 10 isolates equal from both sets by agar well diffusion. Thirty two isolate observed from soil samples of 11 places which were not nearby medicinal plants and 36 isolate observed from soil samples collected surrounding 11 different medicinal plants. (A)OS1, (A)OS3, (A)AI1, (A)TF1 and (A)RI1 were most potent isolates produced from soil surrounding medicinal plant compare to set 2. It was found set1 showed 72.22 % and set 2 showed 53.12 % activity.

Interspecies interactions of halophilic and halotolerant actinomycetes: An example from a salt

Interspecies interaction of actinomycetes will express new gene clusters and may therefore affect the pigmentation, sporulation and production of secondary metabolites. Actinomycetes strains were isolated from Howze Soltan Salt Lake. Binary actinomycete interaction assay was conducted to evaluate its effect on colony morphology and antibiotic production. The molecular identification of the induced strains was performed. A total of 18% of isolates induced antibiotic production of 22% of the other strains against methicillin resistance Staphylococcus aureus (MRSA) and 44 % of them inhibited that of 31 % of antibiotic production in other actinomycete strains. The extract of the selected strains had an inhibitory effect on the pathogen growth. Based on molecular identification, the selected isolates, called act 32, shared 98% similarity with Streptomyces peucetius. It is expected that by screening of actinomycetes from untouched environments and co-culture method, new metabolites can be found to treat antibiotic-resistant infectious diseases.

Isolation and screening of actinomycetes from Ulva lactuca compost sample for their enzymatic and antibacterial activities

Isolation and screening of actinomycetes from Ulva lactuca compost sample for their enzymatic and antibacterial activities

English

English

Isolation and Screening of Antimicrobial and Extracellular Pigment Producing Actinomycetes from Chambal Territory of Madhya Pradesh Region, India

In present study the objective is to isolate, characterize and study of biological activity of pigment producing actinomycetes. Samples were collected from rhizosphere soil of Chambal territory and other parts of Madhya Pradesh regions. Screening of actinomycetes was done on the basis of pigment diffusion ability in different media. Characterization of the actinomycete was made by scanning electron microscopy and 16s rRNA molecular sequencing. The antimicrobial activity of selected actinomycete was done by over lay agar method and well agar diffusion method against various pathogenic microorganisms. Among 85 actinomycetes isolates, only ARITM02 showed pigment producing and diffusion ability in media. The Gram staining and scanning electron microscopy confirmed the linear chain structure of actinomycete. Morphological, biochemical and molecular analysis confirmed the isolate belong to genus Streptomyces. Streptomyces isolate also shown notable antimicrobial activities against various pathogens. These significant results make Streptomyces suitable for further investigation and industrial exploitation. Present investigation reveals that Chambal territory region of Madhya Pradesh has great ability to produce potent actinomycetes which possess pigment production and antimicrobial activities against various pathogens.

Isolation and screening of actinomycetes from Algerian soil for their enzymatic and antimicrobial activities

Isolation and screening of actinomycetes from Algerian soil for their enzymatic and antimicrobial activities

DIVERSITY AND ANTIMICROBIAL ACTIVITY OF MANGROVE SOIL ACTINOMYCETES ISOLATED FROM TANJUNG LUMPUR, KUANTAN

Actinomycetes are biotechnologically important for their unrivalled capacity to produce bioactive secondary metabolites. Although thousands of antibiotics have been discovered from actinomycetes, these represent only a small fraction of the entire reservoir. Thus, screening of actinomycetes from poorly studied environment is a valuable attempt. In the present study, an effort was made to isolate, identify and evaluate the antimicrobial activities of actinomycetes from Tanjung Lumpur Mangrove Forest of Pahang, Malaysia; an underexplored ecosystem. Out of 1366 actinomycetes that were successfully enumerated, a total of 40 representative isolates were selected for further evaluation. The antimicrobial activity of the representative isolates were first assessed using the cross streak method against Bacillus subtilis, Candida albicans, Escherichia coli, Serratia marcescens and Staphylococcus aureus. Twenty five isolates displayed antagonistic potential against at least one of the test organisms. Of this, 40% exhibited antibacterial activity, 24% exhibited antifungal activity and 36% displayed both. The cell–free supernatant of the active isolates were then further evaluated using the agar well diffusion method, in which only 4 isolates displayed inhibitory activity. A total of 13 representative isolates were identified and characterized using 16S rRNA gene partial sequencing. They were further classified into 7 genera namely Streptomyces, Micromonospora, Rhodococcus, Gordonia, Pseudonocardia, Mycobacterium and Actinophytocola. These findings suggested that mangrove of Tanjung Lumpur is a rich source of actinomycetes for the discovery of bioactive secondary metabolites.

Screening of Actinomycetes From Lipar Area of Oman Sea to Investigate the Antibacterial Compounds

compounds. Objectives: The purpose of this study was to isolate the actinomycetes producing antibacterial compounds. Materials and Methods: A total of 35 actinomycetes were isolated from Oman Sea (Lipar Area). To investigate antibacterial activity, the isolated actinomycetes were assessed against reference and pathogenic bacteria, including Staphylococcus epidermidis, Staphylococcu intermedius, Staphylococcu chromogenes, Staphylococcu saprophyticus, Bacillus cereus and methicillin-resistance Staphylococcu aureus, Pseudomonas, Listeria, Klebsiella, Salmonella, Acinetobacter, and Escherichia coli O157:H7, using the cross streak method. Results: Based on the morphological characterization, 35 isolated cases belonged to actinomycetes and %94 of them had the ability to produce antibacterial compounds. In the cross streak method, most of the isolated bacteria have antibacterial activity against reference S. aureus among Gram-positive bacteria and Acinetobacter among Gram-negative bacteria. Inhibition zone diameters were measured between 2-25 and 1-20 mm for Gram-positive and -negative bacteria, receptivity. Conclusions: Preliminary results indicate that the native Iranian Actinobacteria could be considered a suitable option for screening of the new antibacterial compounds. Molecular research and antibacterial compound extraction against the aforementioned pathogenic strains are also being conducted.

Screening of Actinomycetes for Enzyme and Antimicrobial Activities from the Soil Sediments of Northern Tamil Nadu, South India

The present study involves the screening of actinomycetes for enzymes and antimicrobial activities from the soil sediments of Northern Tamil Nadu, South India. Actinomycetes from the soil samples were isolated by pour plate technique on Actinomycetes Isolation Agar. Morphological characteristics of the isolates were studied based on microscopic appearance. Actinomycetes isolates was screened for the production of different extracellular enzymes like amylase, protease and lipase. In the screening for enzyme activity, the actinomycetes strains showed amylase activity, protease activity and lipase activity. Preliminary screening for antimicrobial activity of actinomycetes isolates were performed by cross streak plate method. Active form of 82 isolated strains showed activity against one or more bacteria and exhibited potential antifungal activity. The active strain was subjected to cultural, molecular identification and optimization of fermentation medium, solvent extraction and antimicrobial activity for crude extracts. Based on the primary antimicrobial proficiency, Loyola AR1 strain was selected for further studies. Ethyl acetate extract showed good antimicrobial activity when compared to butanol extract. The partial 16s rRNA sequence analysis of Loyola AR1 isolate identified to be Streptomyces sp. and the sequence was submitted to the Gene Bank (HM163569).

Selman A. Waksman, Winner of the 1952 Nobel Prize for Physiology or Medicine

The history of the discovery and development of streptomycin is reviewed here from the personal standpoint of a member of Dr. Selman Waksman's antibiotic screening research team. The team approach of eight individuals illustrates how the gradual enhancement of the screening methodology was developed. I illustrate three study periods with key aspects in the development of streptomycin which led to a Nobel Prize being granted to Professor Waksman. One item not previously emphasized is the employment of a submerged culture technique for large-scale production of streptomycin, thus enabling rapid animal testing and human clinical trials with Mycobacterium tuberculosis. Another is that purified streptomycin was shown by Dr. Waksman to be distinctly different from the substances called natural products, which are no longer patentable in the United States; therefore, streptomycin was found to be patentable. A third item not previously emphasized is his emphasis on the screening of actinomycetes, including the newly named Streptomyces genus. All of these factors contributed to the success of streptomycin in the treatment of tuberculosis. In combination, their successes led to Dr. Waksman's department becoming a new pharmacological research area, specializing in drug discovery. These unique accomplishments all burnish the prior rationales used by the Karolinska Institute in granting Dr. Waksman alone the 1952 Nobel Prize for Physiology or Medicine.

Isolation and screening of antibiotic producing actinomycetes from soils in Gondar town, North West Ethiopia

ObjectiveTo isolate and screen antibiotic producing actinomycetes from potential soil samples of Gondar town, Ethiopia. MethodsFifteen soil samples were collected, serially diluted and spread on starch casein and oat meal agar supplemented with amoxicillin and cyclohexamide for inhibition of bacteria and fungi, respectively. Cross streak method was used to check antagonistic activity of isolated actinomycetes against test organisms. Solid state fermentation and crude extraction were used for the production of antibiotics from isolates. Agar well diffusion was used for antimicrobial activity of crude extracts against test organisms. ResultsThree isolates (Ab18, Ab28 and Ab43) have been shown high antagonistic activity during primary screening. Inhibition zones obtained from crude extracts showed significance differences when compared with standard antibiotics tested against test organisms (P<0.05). Inhibition zone of crude extracts from isolate Ab18 against Klebsiella pneumonia ATCC7000603 and Escherichia coli ATCC25922 were (14±1) mm and (35±1) mm, respectively which were strong active when compared to amoxicillin (0 mm) and tetracycline [(13±1) mm for Klebsiella pneumonia ATCC7000603 and (33±1) mm for Escherichia coli ATCC25922]. Crude extracts from isolate Ab18 showed (20±1) mm and (15±1) mm inhibition zones against methicillin resistant Staphylococcus aureus strains 2 (MRSA2) and MRSA4, respectively. Crude extract from isolate Ab43 has shown inhibition zones of (16±1) mm and (17±1) mm against MRSA2 and MRSA4, respectively. Combination of Ab18 and Ab43 has shown high antimicrobial activity (18±1) mm against MRSA2 and MRSA4. ConclusionsThere was not any scientific report on soil actinomycetes producing antibiotic in the study areas. Therefore, isolation and screening of actinomycetes from such areas in optimum condition may contribute the discovery of new antibiotics. Potent antibiotics from these actinomycetes could contribute a lot to fight against antibiotic resistant pathogens. Selected isolates have been shown strong antimicrobial activity against resistant pathogens. Further purification, structural elucidation and characterization are recommended to know the quality, novelty and commercial value of these antibiotics.

Screening of Actinomycetes from Marine Environments and the Inhibitory Activity against Pathogen &lt;i&gt;Staphylococcus aureus&lt;/i&gt;

Forty-one actinomycetes isolated from sea sand of beach in Weihai were tested using the agar diffusion method, and Staphylococcus aureus was selected as the tested bacteria. Strains with significant inhibitory activity were chosen to ferment in the GS medium, then the supernatant was extracted using ethyl acetate, and the vitro assay of crude extracts was performed. Results indicate: there are eight strains having significant activity, accounting for 31.7% of the total. The suppression of MA27 and MA41 are much significant than the other six strains, and their inhibitory diameter is 15.00±1.14mm and 14.00±2.83mm, respectively. Six extracts of antibacterial metabolites with ethyl acetate were assayed. Three strains (MA27, MA36, SHXF02) have antibacterial activity under the concentration of 2mg/disc, their inhibitory diameter is 29.00±2.64mm, 18.67±2.31mm and 14.33± 0.58mm, respectively.

Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes

Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes

Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes.

Actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. A total of 48 isolates were obtained from 12 samples of earthworm castings. Highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). The growth patterns, mycelial coloration of abundance actinomycetes were documented. The dominant genera Identified by cultural, morphological and physiological characteristics were Streptomyces (60.41%) followed by Streptosporangium (10.41%),Saccharopolyspora (6.25%) and Nocardia (6.25%). Besides these, other genera like Micromonospora, Actinomadura, Microbispora, Planobispora and Nocardiopsis were also recovered but in low frequency. Among the 48 isolates, 52.08% were found active against one or more test organisms. Out of 25 active isolates 16% showed activity against bacterial, human fungal as well as phytopathogens. Among 48 isolates 38, 32, 21, 20, 16 and 14 produced enzyme amylase, caseinase, cellulase, gelatinase, xylanase and lipase respectively while 10 isolates produced all the enzymes. More interestingly 2, 3, and 1 isolates produced amylase, xylanase and lipase at 45°C respectively. In the view of its antimicrobial activity as well as enzyme production capability the genus Streptomyces was dominant. The isolate EWC 7(2) was most promising on the basis of its interesting antimicrobial activity and was identified as Streptomyces rochei. The results of these findings have increased the scope of finding industrially important actinomycetes from earthworm castings and these organisms could be promising sources for industrially important molecules or enzymes.

Screening of Actinomycetes with High Producing Xylanase

Xylanase has a wide range of potential biotechnological applications in pulp and bleaching processes, textile industries, food and bread making, fruit juice clarification and so on. In order to explore and utilize xylanases using actinomycetes, collected dozens of soil samples beneath decaying wood or leaf debris of different parts of China, 102 xylanase producing actinomycetes were isolated by plate screening with home-made corncob xylan as the sole carbon source. All strains degraded xylan and produced evident xylan hydrolyzed circles. 37 actinomycetes were selected by shake flask cultivation, and among them 7 stains with high producing xylanase were submerged fermentation again. Xylanase activities of 7 strains except L1904 (158U/ml) were all beyond 200U/ml and stable. L2001 as the most promising strain, xylanolytic activity of which was 815U/ml. The project set up foundation for the further study in the future.

Screening of Actinomycetes from Mangrove Ecosystem for L-asparaginase Activity and Optimization by Response Surface Methodology

Marine actinomycetes were isolated from sediment samples collected from Pitchavaram mangrove ecosystem situated along the southeast coast of India. Maximum actinomycete population was noted in rhizosphere region. About 38% of the isolates produced L-asparaginase. One potential strain KUA106 produced higher level of enzyme using tryptone glucose yeast extract medium. Based on the studied phenotypic characteristics, strain KUA106 was identified as Streptomyces parvulus KUA106. The optimization method that combines the Plackett-Burman design, a factorial design and the response surface method, which were used to optimize the medium for the production of L-asparaginase by Streptomycetes parvulus. Four medium factors were screened from eleven medium factors by Plackett-Burman design experiments and subsequent optimization process to find out the optimum values of the selected parameters using central composite design was performed. Asparagine, tryptone, d) extrose and NaCl components were found to be the best medium for the L-asparaginase production. The combined optimization method described here is the effective method for screening medium factors as well as determining their optimum level for the production of L-asparaginase by Streptomycetes parvulus KUAP106.

Comparative Evaluation of Two Methods for Determination of Proteinase Inhibitory Activity of Actinomycete

ABSTRACTTwo highly sensitive analytical methods were used for screening of actinomycetes with the aim to select perspective producers of proteinase inhibitors (PI). There was a correlation between the results obtained by means of both methods for the highly active strains (inhibitory activity over 1000 KIU/ml). The proteinase inhibitors produced by the atypical streptomycetes Micromonospora sp. and Streptosporangium longisporum are active towards trypsin and subtilisin BPN'. Some of the strains did not inhibit trypsin but there was such activity towards subtilisin BPN' according to the “plate assay”. The inhibition of trypsin by the low active strains is proved quantitatively. The results obtained by the “plate assay” are negative towards both enzymes. There was an interesting phenomenon by the strain S. albogriseolus 444, which was proved by both methods. Its variant, active in the synthesis of antibiotic substances, produces PI against trypsin and subtilisin BPN', whereas the non-active variant produces PI only against subtilisin.