Antibiotic-producing Bacteria Research Articles

Resistance\u2010guided isolation and characterization of antibiotic\u2010producing bacteria from river sediments

BackgroundTo tackle the problem of antibiotic resistance, an extensive search for novel antibiotics is one of the top research priorities. Around 60% of the antibiotics used today were obtained from the genus Streptomyces. The river sediments of Bangladesh are still an unexplored source for antibiotic-producing bacteria (APB). This study aimed to isolate novel APB from Padma and Kapotakkho river sediments having the potential to produce antibacterial compounds with known scaffolds by manipulating their self-protection mechanisms.ResultsThe antibiotic supplemented starch-casein-nitrate agar (SCNA) media were used to isolate antibiotic-resistant APB from the river sediments. The colonies having Streptomyces-like morphology were selectively purified and their antagonistic activity was screened against a range of test bacteria using the cross-streaking method. A notable decrease of the colony-forming units (CFUs) in the antibiotic supplemented SCNA plates compared to control plates (where added antibiotics were absent) was observed. A total of three azithromycin resistant (AZR) and nine meropenem resistant (MPR) isolates were purified and their antagonistic activity was investigated against a series of test bacteria including Shigella brodie, Escherichia coli, Pseudomonas sp., Proteus sp., Staphylococcus aureus, and Bacillus cereus. All the AZR isolates and all but two MPR isolates exhibited moderate to high broad-spectrum activity. Among the isolates, 16S rDNA sequencing of NAr5 and NAr6 were performed to identify them up to species level. The analyses of the sequences revealed that both belong to the genus Streptomyces.ConclusionsThe results from these studies suggest that manipulation of the self-resistance property of APB is an easy and quick method to search for novel APB having the potential to produce potentially novel antibacterial compounds with known scaffolds.

Isolation, Identification and Screening of Bacteria with Antibiotic Production Potential from Termite Mounds

Antibiotics are of great importance in medicine, that are harmful to the growth and metabolic activities of bacteria. Ever increasing search is going on in the hope that agents’ superior to these and other antibiotics now in use might be isolated. Present study seeks to screen bacteria with antibiotic producing potentials from termite mounds. Eight (8) termite mound samples were collected from the study sites (Shamawa, Dundaye, G/Yaro and Gumburawa), processed and bacteria were isolated and identified using culturing methods, gram staining and biochemical characterization methods. The isolates were further tested for antibiotic production using crowded plate techniques on muellar-hilton agar. Morphological and cultural studies shows that twenty gram positive and six gram negative bacteria species were identified namely Bacillus spp, Citrobacter freundii, Enterococcus cloacae, Enterococcus faecalis, E. coli, K-pneumoniae, Pseudomonas spp, Staph aureus, Staph lentus and Staph ureae. Eleven bacteria species out of the fourteen isolates showed antibiotic production activity against Staphylococcus epidermidis and 3 were not active against the test organism. These include E. coli and Pseudomonas spp. The zone of inhibition formed are Bacillus cereus 4 mm, Bacillus subtilis 5 mm, Bacillus megaterium 2 mm, Citrobacter freundii 4 mm, Enterococcus cloacae 2 mm, and Enterococcus faecalis 2 mm respectively. The result of this research indicates that termites mound may be used as a source of antibiotic producing bacteria.

Anthill Inhibiting Bacteria, a Promising Source of Bio Efficacy

The investigation into soil bacteria has been widely studied and becoming increasingly appreciated as an exceptional reservoir of unique naturally occurring biologically active metabolites with pharmaceutical applications. This article aimed to isolate, identify and biochemically characterize antibiotic-producing bacteria from anthill soils in the permanent site of Ibrahim Badamasi Babangida University, Lapai (IBBUL), Niger State, Nigeria. The sum of ten samples were collected from five sampling sites, the sampling was done in threefold (morning, noon and evening) and analyzed adopting standard microbiological protocols. The obtained result revealed that the total bacteria count in the morning ranges from 2.1×107 cfu/mL to 1.4×106 cfu/mL, noon count ranges from 3.1×107 to 2.6×106 cfu/mL while evening count was in the range of 2.1×107 cfu/mL to 1.7×106 cfu/mL. A total number of five (5) bacteria were isolated as Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Bacillus lentus and Micrococcus reseus. The total prevalence of the bacterial isolates in the morning, noon and evening were calculated as B. subtilis (109.08%), S. epidermidis (36.36%), M. reseus (36.36%), B. lentus (63.63%), and S. aureus (54.54%) respectively. These isolates were further assayed against Escherichia coli, Salmonella typhi, Klebsiella sp. and Staphylococcus aureus. The antibacterial outcome showed that two (2) (40%) anthill isolates exhibited antibacterial activity against three (3) tested bacteria (Escherichia coli, Salmonella typhi and Staphylococcus aureus). This research study has showcased that the production of inhibitory substances are common among some of the bacterial strains isolated from anthills.

ISOLATION OF ANTIBIOTIC PRODUCING BACTERIA FROM POND SOIL, GUDLAVALLERU

Soil being a major reservoir for microorganisms it is a source of interest for isolation of antibiotic producing organisms. The emergence of antibiotic resistance and need for better, broad spectrum antibiotics is always in high demand. In the present study, antibiotic producing bacteria were isolated from a local soil sample. Total ten soil samples were collected from local pond aseptically and subjected to serial dilution. Crowded plate technique was employed for the isolation of the colony. Total five isolated were isolated which exhibited zone of inhibition around the colony. The isolated colonies were subjected to morphological, microscopical and biochemical characterization. All five colonies were found to be gram positive, non-sporulating organisms and found they belong to the Actinobacteria class. The isolated colonies were subjected to screening for antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis and Yeast by perpendicular streak method. The primary screening results conclude that except one colony all have good antimicrobial activity. One colony found to be highly potential activity which had inhibition towards gram positive, gram negative, sporulating and fungal activity. This study may contribute in providing information on the antibiotic producing microorganisms in soil. Further characterization, purification, and structural elucidation are recommended to know the novelty, quality and commercial value of these antibiotics.

Implementation of Antibiotic Discovery by Student Crowdsourcing in the Valencian Community Through a Service Learning Strategy.

Antibiotic misuse is a public health problem due to the appearance of resistant strains in almost all human pathogens, making infectious diseases more difficult to treat. The search for solutions requires the development of new antimicrobials as well as novel strategies, including increasing social awareness of the problem. The Small World Initiative (SWI) and the Tiny Earth (TE) network are citizen science programs pursuing the discovery of new antibiotics from soil samples and the promotion of scientific culture. Both programs aim to bring scientific culture and microbiological research closer to pre-university students through a crowdsourcing strategy and a Service Learning (SL) educational approach, with a 2-fold objective: to encourage students to pursue careers in science and to involve them in the discovery of soil microorganisms producing new antimicrobials. SWI and TE projects were put into practice in Spain under the common name MicroMundo. MicroMundo@Valencia was implemented at the Universitat de València (UV) during the academic years 2017–2018 and 2018–2019. It trained 140 university students to disseminate this initiative into 23 high/secondary schools, and one primary school, involving about 900 people (teachers and students) as researchers. A total of 7,002 bacterial isolates were obtained from 366 soil samples and tested for antibiosis at UV and high/secondary school centers. About 1 or 7% of them produced inhibition halos for the Escherichia coli or Bacillus cereus target strains, respectively. Geolocation of sampling sites by an application developed ad hoc and Kriging analysis also allowed detection of soil foci of antibiotic-producing bacteria. Evaluation of the project by university, high/secondary, and primary school students revealed their strong positive perception and their increased interest in science, as a consequence of acquiring new scientific and pedagogical concepts and skills that they were able to pass on to other classmates, younger students, or relatives. To further expand the dissemination of the project in the Valencian Community, diverse extramural activities deemed to include a gender perspective and aimed at different age groups, were also carried out, obtaining very satisfactory results, increasing sensitivity and awareness to the global antibiotic crisis.

Keanekaragaman Mikrob Fungsional Rizosfer Nanas dengan Berbagai Tingkat Produktivitas

Functional microbes of rhizosphere play important roles in nutrient transformation and controlling disease as well as in supporting plant growth and development. However, there is no study on the role of functional microbes on pineapple productivity. The purpose of this study was to investigate the abundance and diversity of soil functional microbes at different growth phases at two levels of productivity and their correlations to disease incidence. The research process included sampling of pineapple rhizospheric soil from vegetative and generative phases pineapples at low and high plant productivity sites, observations of disease incidence, and isolations of functional microbes. Functional groups of bacteria were Azotobacter, phosphate-solubilizing bacteria, potassium-solubilizing bacteria, antibiotics-producing bacteria, IAA-producing bacteria, and chitinolytic bacteria. The soil sampling method was simple randomized sampling at 6 locations with an area of each location ± 5 ha with a depth of 20 cm. Rhizosphere were taken in plants grown in high productivity area (>60tons/ha) and low productivity area (<60 tons/ha) in vegetative and generative phases. The results showed that potassium-solubilizing bacteria, chitinolytic bacteria, and IAA-producing bacteria were more abundant during the generative phase compared to those during vegetative phase. While Azotobacter, phosphate-solubilizing bacteria, and antibiotic-producing bacteria were more predominant during vegetative phase at various crop productivy. Total density of microbes was higher in soil with high crop productivity than that in soil with low crop productivity. The abundance of chitinolytic bacteria and IAA-producing bacteria had negative correlation with disease caused by Erwinia chrysanthemi and Phytophthora cinnamomi.
 Keywords: chitinolytic bacteria, growth phase, IAA, pineapple disease

Isolation of Antibiotic Producing Bacteria from Lake Soil

Isolation of Antibiotic Producing Bacteria from Lake Soil

MicroMundo Upside Down: Targeted Searching for Antibiotics-Producing Bacteria From Soil With Reverse Antibiosis Approaches.

Tiny Earth (TE) is a popular international citizen science program aimed at improving public awareness on the growing antimicrobial resistance problem of which MicroMundo Albacete is a Spanish node. With a protocol that is focused on the isolation of antibiotics-producing actinomycetes from soil, 70% of the high school students in MicroMundo Albacete 2020 isolated colonies with antagonistic activity against Gram-positive tester bacteria. However, no activity was found against Gram-negative bacteria. Here, we further adapted the protocol toward a more targeted screening that also enables isolation of antagonistic bacteria against Gram negatives using two different reverse-antibiosis approaches involving a spraying technique or flipping soil sample disks upside down. Exploiting the soil samples from MicroMundo Albacete 2020, the new approaches yielded isolation of actinomycete bacteria with antagonistic activity against Gram-negative as well as Gram-positive tester bacteria. We propose that (educational) science programs which aim to search for antibiotic-producing bacteria may implement these approaches in their protocol to promote a successful and stimulating outcome of the experiment for the participating students.

Isolation of Antibiotic-Producing Bacteria from Extreme Microhabitates in Mangrove Ecosystem

This study aims to isolate and identify the antibiotic-producing bacteria from extreme microhabitates in the marine ecosystem against fish pathogenic bacteria (V. alginolyticus, A. hydrophila, dan Pseudomonas sp). Microbes from samples were grown on NA and TSA media. Well grown colonies were examined for their ability to produce antibiotics against the pathogens by the streaking and paperdisc diffusion method on MHA. Potential isolates were identified through a series of phenotypic and genotypic test. A number of 4 antibiotic-producing bacteria were selected. DNA of the bacteria were extracted using DNA easy mini column and amplified by using Kappa PCR kit with 16S rDNA 1A and 16S rDNA2A primers. The PCR results were analyzed on a 1.5% agarose gel in Tris-acetat-EDTA (TAE) electrophoresisuffer (4 mM Tris-acetate and 1 mM disodium EDTA at pH 8.0). The electrophoresis process was carried out at 60 mA (100-120 v) for 30-45 minutes read by UV Transilluminator. Isolate Ni5 have a 99% homological similarity to Bacillus amyloliquefaciens strain SH20. Bacterial isolate Xy3 has a 100% homological similarity with Bacillus cereus strain NY180. Isolate S11 has a 97% homological similarity with Enterobacter hormaechei strain CGAPGPBBS-064. Isolate K22 has a 99% homological resemblance to Klebsiella pneumoniae strain MW-W 754.

Interaction of mutant PBP2a and bioactive compounds from Streptomyces with anti-MRSA activities

Methicillin-Resistant Staphylococcus aureus (MRSA) is the leading cause of nosocomial infections in hospitals. Treatment of MRSA infection using ceftaroline has been reported to be resistant due to mutations in the Penicillin Binding Protein (PBP)2a. In silico’s approach through virtual screening can analyze the bioactive compounds that can bind effectively to mutant PBP2a. The potential source of bioactive compounds with anti-MRSA activities is Streptomyces, which is the main antibiotic-producing bacteria. Thus, the study aimed to analyze the interactions of PBP2a/mutant PBP2a against ceftaroline and the interactions between mutant PBP2a against bioactive compounds from Streptomyces. The protein receptors were PBP2a (PDB 3ZG0) and mutant PBP2a (PDB 4CPK). The ligands used were ceftaroline (CID 9852981) as control and nine bioactive compounds produced by Streptomyces. Protein preparation and visualization used Discovery Studio, ligand preparation used Marvin, and molecular docking used Autodock4. The alignment results showed that mutant PBP2a has a more extended amino acid sequence (643 amino acids) than PBP2a (641 amino acids). The mutations that occurred in mutant PBP2a caused conformation changes in the active site of mutant PBP2a so that the interaction between ceftaroline and mutant PBP2a decreased. The virtual screening results indicated that 1-acetyl-β-carboline was the most potent compound as anti-MRSA with the lowest binding energy (-7.12 Kcal/mol) compared to ceftaroline (-6.32 Kcal/mol). The amino acids involved in the binding of 1-acetyl-β-carboline with PBP2a mutant were Ser403, Ser461, Asn464, Thr600; Ser462, Tyr446, and Ala642. This result suggests that 1-acetyl-β-carboline has better interaction with mutant PBP2a, hence might serve as a potential anti-MRSA compound.

Autoclaving Nest-Material Remains Influences the Probability of Ectoparasitism of Nestling Hoopoes (Upupa epops).

Simple SummaryMicroorganisms may have direct negative effects on their animal hosts and cause diseases, but some others provide animals with protection against infections, parasites, and even predators. However, parasites or predators might take their cue from odors produced by bacteria, even those from protecting microorganisms, which could turn net benefits of bacteria that are a priori considered beneficial into a neutral or even negative outcome. This possibility has scarcely been studied in wildlife populations; we manipulated the bacterial community of nest-material of hoopoes and detected a negative effect in terms of the intensity of parasitism by blood-sucking flies that nestlings suffer. We also detected a positive link between the bacterial density of the nest-materials and the intensity of ectoparasitism, which further points at the importance of the bacteria determining the level of parasitism. Blood-sucking ectoparasites are also disease vectors, affecting both humans and livestock, and considering the role of the bacterial environment might help to establish new transmission control protocols.Nest bacterial environment influences avian reproduction directly because it might include pathogenic- or antibiotic-producing bacteria or indirectly because predators or ectoparasites can use volatile compounds from nest bacterial metabolism to detect nests of their avian hosts. Hoopoes (Upupa epops) do not build nests. They rather reuse holes or nest-boxes that contain remains of nest-materials from previous breeding seasons. Interestingly, it has been recently described that the nest’s bacterial environment partly affects the uropygial gland microbiota of hoopoe females and eggshells. Blood-sucking ectoparasites use chemical cues to find host nests, so we experimentally tested the hypothetical effects of microorganisms inhabiting nest-material remains before reproduction regarding the intensity of ectoparasitism suffered by 8-day-old nestling hoopoes. In accordance with the hypothesis, nestlings hatched in nest-boxes with autoclaved nest-material remains from the previous reproductive seasons suffered less from ectoparasites than those hatched in the control nest-boxes with nonautoclaved nest-material. Moreover, we found a positive association between the bacterial density of nest-material during the nestling phase and ectoparasitism intensity that was only apparent in nest-boxes with autoclaved nest-material. However, contrary to our expectations, nest bacterial load was positively associated with fledgling success. These results suggest a link between the community of microorganisms of nest-material remains and the intensity of ectoparasitism, and, on the other hand, that the nest bacterial environment during reproduction is related to fledging success. Here, we discuss possible mechanisms explaining the experimental and correlative results, including the possibility that the experimental autoclaving of nest material affected the microbiota of females and nestlings’ secretion and/or nest volatiles that attracted ectoparasites, therefore indirectly affecting both the nest bacterial environment at the nestling stage and fledging success.

Florida woodrat nests are laced with antibiotic-producing bacteria

Florida woodrat nests are laced with antibiotic-producing bacteria

Changes in the ballast water tank bacterial community during a trans-sea voyage: Elucidation through next generation DNA sequencing

Ballast water (BW) mediated bioinvasion is one of the greatest threats to the health of aquatic ecosystems. Bacteria, unlike higher organisms, are transferred in large numbers through BW. Owing to their abundance and potential pathogenicity, they pose a direct threat to the prevailing microbiome in the recipient waters and also to human health. This study investigated the changes in the BW tank bacterial community during a trans-sea voyage from Visakhapatnam port, located along the east coast of India (Bay of Bengal) to Mumbai port, located along the west coast of India (Arabian Sea). Next generation sequencing was used to explore the unculturable segment of bacteria. The BW tank conditions led to a decrease in photoautotrophs and non-spore forming bacteria. On the other hand, biofilm forming and antibiotic producing bacteria, nutrient limiting condition sustaining bacteria, and those capable of synthesizing enzymes prerequisite for active metabolism under stress, increased over time. The shifts in the bacterial community were dependent on mechanisms adopted by the clades to cope with the BW tank conditions. Functional prediction of the bacterial community revealed a significant increase in the core metabolic functions, which enabled the survival of such bacteria. As the voyage progressed, an increase in the total viable bacteria in BW tanks could be attributed to the decrease in the abundance of phytoplankton and zooplankton. At the end of the voyage, the bacterial community in the BW tanks was significantly different, and the species diversity and richness were higher than that of the natural seawater (source water). Pathogenic species were more abundant during mid-voyage than at the end of the voyage, suggesting that voyage duration influences the pathogenic bacterial community. Investigating the fate of the discharged bacterial population at the deballasting point is a way forward in the assessment of marine bioinvasion.

Preliminary Screening of Bacteria Isolated from Insects Living in Poultry for Antibiotic Production

Aim: This present study was conducted to isolate antibiotic producing bacteria from insects living in poultry.
 Place and Duration of Study: Insects living in poultry were collected from poultry farms within Onitsha metropolis in Anambra State between April 2018 and September 2018.
 Methodology: The gut of one hundred insects; (Musca domestica and Alphitobius diaperinus) were analyzed. The insects were dissected and emulsified in 10ml of peptone water. The dilutions were cultured on Nutrient agar and Blood agar for 24 h. The bacterial isolates were characterized using molecular identification. The DNA was extracted from the identified isolates and analyzed by 16S rRNA. In preliminary screening, the isolates were inoculated into Muller Hinton agar using agar plug. The promising isolate showing antagonism was subjected to submerged fermentation method and the secondary metabolites were extracted. Screening of the secondary metabolites extract was done using agar well diffusion. The minimum inhibitory concentration (MIC) of the secondary metabolite was determined using broth dilution method at different concentrations. The inhibitory activity of the organism was checked against four bacteria namely; Bacillus subtilis, Salmonella serovar typhi, Escherichia coli and Staphylococcus aureus.
 Results: The sequence analysis revealed the strains to be Lysinibacillus macroides, Paealcaligenes hermetiae, Bordetella flabilis, Bacillus aerophilus, Klebsiella variicola. Lysinibacillus macroides showed antagonism against the test bacteria during the preliminary test. After fermentation, the secondary metabolite extracts from Lysinibacillus macroides exhibited antibacterial activities against Salmonella Serovar Typhi, Staphyloccus aureus and Bacillus subtilis at different concentrations.
 Conclusion: The extracts from bacterial isolate; Lysinibacillus macroides exhibited antibacterial activities against Bacillus subtilis, Salmonella serovar typhi and Staphylococcus aureus. The extracts may serve as a new drug molecule produced from natural source when purified.

Isolation and Characterization of an Antibiotic‐producing Advenella Species

Antibiotic resistance mechanisms in pathogenic bacteria paired with the general overuse of antibiotics has caused an exponential decrease in the efficiency of many antibiotics. To search for producers of novel antibiotics, this scientific research has turned to the most naturally abundant microbial source, soil. Specifically, the isolation and identification of antibiotic‐producing bacteria from a soil sample was the primary objective of this research. A soil sample collected in late January of 2019 from a mountain edge located at the Chalon campus of Mount Saint Mary’s University‐Los Angeles underwent serial dilutions and plating to isolate bacteria. Once isolated, the bacteria were screened against various ESKAPE relatives, and a viable producer against Bacillus subtilis was identified. The producer’s 16S rRNA gene was amplified through colony PCR, purified through gel electrophoresis, and sequenced. The gene sequence of the producer identified it as a lesser known soil microbe, Advenella kashmirensis (98.41%). Prior research has described Advenella kashmirensis as a sulfur‐oxidizing, chemolithotrophic, gram‐negative soil bacteria, but this bacteria species has not been previously linked to antibiotic production or pathogen inhibition. Therefore, research continued with repeated, successful screenings against B. subtilis, as well as with efforts to support the identification of the producer through the following biochemical tests: urease (positive), catalase (positive), nitrate (positive, reduction beyond nitrite), gelatin (negative), and citrate utilization (negative). Future work will involve further characterization of the isolate through additional biochemical testing as well as attempts to isolate and purify the antibiotic.

Screening and Characterization of Antibiotic Producing Organisms from Waste Dump Soil Sample

This study was designed to screen and characterize antibiotic producing bacteria and fungi from soil samples from a waste dump site in Enugu. The molecular characterization of the isolates was performed by using Zymo Research Quick-DNA fungi/bacteria miniprep kit. The bacteria isolates were Providencia stuartii, Providencia alcalifaciens. Bacillus sp., Streptococcus sp., Micrococcus sp., and Staphylococcus sp while Aspergillus fumigatus and Aspergillus niger were fungal isolates. The efficacy of the Crude Extract (CE) of the antibiotics produced was tested against species of Staphylococcus aureus and Escherichia coli. The CE of antibiotics when compared with a conventional antibiotic (Ciprofloxacin) showed lower antimicrobial activity. The minimum inhibitory concentration of the crude extracts ranged between 12.5% and 25% concentrations while the minimum bactericidal concentration ranged from 25% and 50% concentrations. The findings suggest that these organisms have the potential to produce antibiotics and could be harnessed by pharmaceutical industries for the production of newer antibiotics.

Identification of Antibiotic-Producing Bacteria from Extreme Microhabitat in Molecular Mangrove Ecosystems and Their Activity on Pathogenic Bacteria (Vibrio alginolyticus)

The presence of antibiotic-producing bacteria from microhabitat in mangrove ecosystems can be useful to produce new antibiotics for industrial and environmental conservation. Mangrove ecosystems in Dumai have the potential to possess antibiotic-producing bacteria that have not been much studied. The objective of this research was to obtain antibiotic-producing bacteria from extreme microhabitats in the mangrove ecosystem in suppressing the growth of pathogenic bacterial pathogens (Vibrio alginolyticus). Samples were taken from several microhabitat mangrove areas in Dumai (Kelurahan Purnama Dumai), Riau Province. The survey method is used for identification, antibacterial test against pathogenic bacteria (V. alginolyticus). Bacterial isolation was carried out using the pour plate method and purification was carried out using the quadrant streak method. Identification is carried out through observations of macroscopic, microscopic morphology, biochemical tests, antagonism tests (agar diffusion method on agar nutrient media) and DNA analysis. Sequencing of 16S rDNA from the best antibiotic-producing bacterial isolates indicated that molecularly identified of Bacillus amyloliquefaciens, Bacillus cereus, Enterobacter hormaechei, Klebsiella pneumonia, and Enterococcus gallinarum. All bacteria were able to inhibit the growth of V. alginolyticus

Optimizing Small World Initiative service learning by focusing on antibiotics-producing actinomycetes from soil.

Small World Initiative and Tiny Earth are popular citizen science programs that are implemented worldwide in response to the global antibiotic resistance crisis. When starting up the program in Albacete (Spain), we noted that rates of isolated antibiotic-producing bacteria are generally low. To make the activity more stimulating for participating students, we modified the protocol to obtain more positive results by focusing on isolation of actinomycetes, the main producers of most clinically used antibiotics. Adaptations involved redesigning culture media, incubation times and temperatures, and modification of the ESKAPE antibiosis experiment by employing an agar-transplantation step. Of 390 bacterial isolates tested, almost 6% tested positive in antibiosis experiments and DNA sequence analysis confirmed that all positives are actinomycetes, demonstrating that our protocol is efficient toward isolating antibiotic-producing actinomycetes from soil. Evaluation forms filled by participating students indicated that the program was received very positively and that our modifications contribute to make this educational program more stimulating and efficient.

Isolation and Identification of Antibiotic Producing Bacteria from Soil Samples of Abattoir in Lapai, Niger State, Nigeria

Antimicrobial agents or antibiotics are the most significant commercially available and utilized secondary metabolites, which are highly produced by the soil microbes (bacteria and fungi) and found to be effective and broad spectrum. Microbes produce metabolic products (antimicrobial agents) through the process called antibiosis. Majority of the classes of antibiotics used are derivatives of animals (microbes) and floras (plants). But currently, the microbial resistance is at the top gear which requires more effort to come up with novel structure, effectual, toxic free and reasonable cost of new antimicrobial products against microbial infections. In the present study, a trial was made to isolate, identify and characterize the antibiotic producing bacteria from the soil samples collected from different sites of abattoir in Lapai, using the standard microbiological techniques. A total of nine (9) bacterial of both groups (Gram positive and negative) which includes Corynebacterium diphtheriae, Bacillus cereus, Escherichia coli, Enterobacter aerogene, Clostridium specie, Bacillus subtilis, Pseudomonas species, Staphylococcus aureus and Klebsiella pneumoniae were isolated in the course of the study. Pseudomonas species was the most frequently isolated bacteria (33.33%) while the rest of the isolates were 8.33% across the five different sampling sites. These isolates were further screened against some pathogenic microbes viz, Salmonella sp, Klebsiella pneumoniae, Pseudomonas aeruginosa and Candida albicans. Three of the bacterial isolates isolated from the abattoir were found to exhibits antimicrobial activity against two pathogenic bacteria used in this study. This study indicates that some of the soil microorganisms could be an interesting source of antimicrobial bioactive substances.

Screening for Antibiotic-Producing Bacteria from Imbak Canyon Conservation Area (ICCA)

Antibiotic resistance is an escalating threat to public health. Therefore, there is an urgent need for new antibiotics. This study aims to screen for antibiotic-producing microorganisms from the forest soil of Batu Timbang. Soil samples were collected, diluted and spread plated onto 1/5 Nutrient Agar (NA) and Actinomycete Isolation Agar (AIA) for the isolation of antibiotic-producing microorganisms. A total of 180 bacterial isolates were screened for their antibiotic-producing ability, and ten were tested positive for inhibitory activity against one or more test pathogens via agar overlay assay (Staphylococcus aureus ATCC BAA-1717, Enterococcus faecalis ATCC 700802, and Acinetobacter baumannii ATCC BAA-1605). Ten bacterial isolates were subjected to 16S rRNA gene amplification and gene sequence analysis. The isolates were identified to be closely related to the genus Variovorax, Streptomyces, Kitasatospora, Chromobacterium, Burkholderia, Pseudomonas and Massilia. Three isolates (Variovorax sp. A5, Variovorax sp. A6 and Kitasatospora sp. H8) are potentially novel as these isolates form a different clade from their respective closely related species via phylogenetic tree analysis using reference sequences obtained from GenBank/EMBL/DDBJ databases. The antibiotics produced by the bacterial isolates might potentially be new, as novel species might possess unique biosynthetic gene clusters to produce new compounds. Nevertheless, further taxonomic identification and antibiotic isolation work is required. This study has revealed the potential of antibiotic discovery from Batu Timbang (Imbak Canyon Conservation Area) and its implications in tackling antibiotic resistance.