Microorganisms In Soil Samples Research Articles

Metagenomic evidence for antibiotic-associated actinomycetes in the Karamay Gobi region.

Due to the misuse of antibiotics, there is an increasing emergence and spread of multidrug-resistant (MDR) bacteria, leading to a human health crisis. To address clinical antibiotic resistance and prevent/control pathogenic microorganisms, the development of novel antibiotics is essential. This also offers a new approach to discovering valuable actinobacterial flora capable of producing natural bioactive products. In this study, we employed bioinformatics and macro-genome sequencing to collect 15 soil samples from three different locations in the Karamay Gobi region. First, we assessed the diversity of microorganisms in soil samples from different locations, analyzing the content of bacteria, archaea, actinomycetes, and fungi. The biodiversity of soil samples from outside the Gobi was found to be higher than that of soil samples from within and in the center of the Gobi. Second, through microbial interaction network analysis, we identified actinomycetes as the dominant group in the system. We have identified the top four antibiotic genes, such as Ecol_fabG_TRC, Efac_liaR_DAP, tetA (58), and macB, by CARD. These genes are associated with peptide antibiotics, disinfecting agents and antiseptics, tetracycline antibiotics, and macrolide antibiotics. In addition, we also obtained 40 other antibiotic-related genes through CARD alignment. Through in-depth analysis of desert soil samples, we identified several unstudied microbial species belonging to different families, including Erythrobacteriaceae, Solirubrobacterales, Thermoleophilaceae, Gaiellaceae, Nocardioidaceae, Actinomycetia, Egibacteraceae, and Acidimicrobiales. These species have the capability to produce peptide antibiotics, macrolide antibiotics, and tetracycline antibiotics, as well as disinfectants and preservatives. This study provides valuable theoretical support for future in-depth research.

Investigation of Environmental Effect of Plants in Smoking Area through Analysis of Cadmium and Microorganisms

Objectives:The purpose of this study was to investigate the effect of plants on smoking area and its environment. For this purpose, two different smoking areas (with and without plants) were selected, and the number of smokers and spitting behaviors were monitored. Soil and leaves samples of each smoking area were taken to analyze the concentration of cadmium and distribution of soil microorganisms. Through this investigation, the role of plants in smoking area for the cadmium and microorganisms was estimated. Methods:In the selected smoking areas, number of smokers and the number of spitting behaviors were monitored. Cadmium (Cd) concentrations of leaves, topsoil and rhizosphere obtained from the smoking areas were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). The microorganisms in soil samples were analyzed using denaturing gradient gel electrophoresis (DGGE) and 16s rRNA amplicon sequencing based metagenomics.Results and Discussion:In the case of smoking area with plants, number of smokers and number of total spitting behaviors were 176.67 ± 7.85 and 918.67 ± 40.8 times per hour, respectively. In smoking area without plants, the 153.67 ± 5.44 (smokers) and (829.8 ± 29.36 (spitting behavior) per hour were observed. Among the collected samples from the smoking areas, the highest Cd values (347.117 ± 24.542 μg/kg) were found in leaves of smoking area. In the case of smoking area without plants, the top soil samples showed the highest Cd concentration (295.77 ± 16.64 μg/kg). The results indicate that Cd released from cigarette ash, saliva and smoke can be accumulated in plants and soil. The results suggested that the presence of plants in the smoking area protect the accumulation of Cd in surrounding environments (soil and atmosphere). The metagenomic analysis of the soil samples showed that smoking and spitting behavior also affected microbial system in the smoking areas. The results showed that the microorganisms in smoking area were closely related to the heavy metal removing activities. Conclusion:Results suggested that the cadmium distribution in the smoking areas was significantly affected by the presence of live plants. In addition, the presence of plants in the smoking area induced the difference species microorganisms. These results suggested that the presence of plants in smoking area can protect the spread of cadmium to the surrounding environment.

ISOLATION OF BACTERIA FROM THE SITES OF FEED AND NESTING ACTIVITY OF LARUS DOMINICANUS (GALINDEZISLAND, THE MARITIMEANTARCTIC) AND THEIR CHARACTERISTICS

The aim of the study was to investigate the number of different groups of microorganisms in soil samples from sites of feed and nesting activity of Larus dominicanus (Galindez Island, the maritime Antarctic) and to characterize the physiological and biochemical properties of isolated microorganisms. Methods. In the work standard microbiological and biochemical research methods were used (cultural, microscopy methods, determination of enzymatic activity). Genomic DNA was isolated by soft lysis. The 16 S rRNA gene was amplified using universal primers 27F and 1492R. Identification of isolates was performed based on the determination of the 16 S rRNA gene sequence, physiological and biochemical properties. Results. The number of microorganisms of different groups in soil samples from sites of food and nesting activity of Larus dominicanus (Galindez Island, the maritime Antarctic) was established. 74 isolates of bacteria were isolated. Isolate 2U-K-37, that was isolated from upper layer of soil, and isolate 2B-K-54, that was isolated from a depth of 2–5 cm, were characterized by amylase, lipase, phospholipase, protease activities, the ability to form exopolysaccharides.They were identified by sequencing of the 16 S rRNA gene, physiological and biochemical properties as Pedobacter sp. 2U-K-37 and Pseudarthrobacter sp. 2B-K-54. In the soil samples from sites of feed and nesting activity of Larus dominicanus microorganisms that metabolize nitrogen of organic compounds were the most numerous. Oligotrophic microorganisms and microorganisms that metabolize nitrogen of inorganic compounds were less numerous. The number of microorganisms of groups in the samples from the soil surface and lower layers differed statistically significant. Isolated and identified obligate psychrophilic strain Pedobacter sp. 2U-K-37 and psychrotolerant strain Pseudarthrobacter sp. 2B-K-54 are moderate halophiles that are able to hydrolyze starch, gelatin, tween-20 and synthesize exopolysaccharides.

Influence of hydrocarbon pollution on the structure of the microbial community of soils of the Zaburunye deposit

This article presents the results of determining the microorganisms number in contaminated soil samples from Zaburunye field. This study is devoted to the study of the soil microbial community as a result of the inhibitory effect of hydrocarbon pollution. The relationship between hydrocarbons and the number of ecological and physiological groups of microorganisms was assessed using soil samples with different contamination levels. To study the number of microorganisms, several soil samples (heavily contaminated and slightly contaminated) from Zaburunye field were used. The number of ecological and physiological groups of microorganisms is considered as an important indicator of the soil biological activity, which is influenced by oil pollution. Thus, the results showed that hydrocarbon pollution inhibited the number of microorganisms in soil samples with a degree of hydrocarbon pollution from 22560 ± 28.8 to 33265 ± 19.8 mg/kg soil. A relatively high number of all ecological and physiological groups was noted in all soil samples with a low content of hydrocarbons. Thus, the number on Starch-ammonia Agar was 138.6 ± 8.91 thousand CFU / g soil, and on Nutrient Agar 98.6 ± 2.23 thousand CFU / g soil. The selective effect of oil on the structure of the microbial community of Zaburunye field soils is expressed in the fact that the number of microorganisms is not significantly high in the contaminated soils. Key words: oil, soil, number of microorganisms, bacteria, actinobacteria, micromycetes, hydrocarbon – oxidizing microorganisms.

DIAZINON IMPACT ASSESSMENT ON SOME GEOBIONTS IN THE REPUBLIC OF BASHKORTOSTAN

Background The article shows the effect of the insecticide «Zemlin», the active substance of which is diazinone, on soil organisms and on some plant species. This pesticide is actively used in the agroindustrial sector of the country in the fight against various pests. Aims and Objectives In order to detect the anthropogenic load of the soil ecosystem in the effects of the drug «Zemlin» containing diazinone, and to assess the toxicity of the insecticide on soil organisms, earthrworms ( Lumbricus terrestris L .) and bacteria living in the soil: Pseudomonas sp., Bacillus sp., Arthrobacter sp., Azotobacter sp., Flavobacterium sp. The drug was analyzed for phytotoxicity on onion sprouts ( Allium cepa ), cabbage ( Brassica oleracea ) and Helichrysum arenarium . Biodestruction of diazinon with soil microorganisms-destructors has been investigated. Methods The material for experiments was the drug «Zemlin» in which the active substance is diazinone. A fertile black-and-yellow product, selected from the environmentally friendly territory of the Karmaskalinsky Region of the Republic of Bashkortostan. In this work, experiments were conducted on the effects of the drug on earthworms, taking into account their behavior, modeled the condition of contact of earthworms ( Lumbricus terrestris L.) with the drug. Studies on phytotoxicity were carried out, as test objects used vegetable and floral crops (onion, cabbage, helichrysum). Determining the number of microorganisms in soil samples before and after exposure to insecticide in PC concentrations (production concentration), 2PC and 5PC were carried out by «fingerprinting» in petri dishes on meatpepton agar (MPA) taken as nutrient environment. We planted soil samples and cultivated them from 2 to 5 days in a thermostat at 28 °С. Microorganisms used diazinone as a source of carbon and energy. The change in the destructive material was determined with the help of a thinlayer chromatogram (TSX), the plates SilufolUV-254 were used, the ehuent was acetone, the developer of phosphorus-molybdenic acid ( Rf = 0.3). Chromato-mass spectral analysis was carried out on the device ShimadzuGC-9A. Results Analysis of the effects of the insecticide on the basis of diazinone on earthworms showed that the drug has a high toxic effect. In PC for 3 days live earthworms were observed 60 %. In an experiment to study phytotoxicity, the analysis showed that after treatment with the drug «Zemlin» with different concentrations: PC, 2PC, 5PC and control (drug free) the length of the above-ground and underground parts of plants that were etched, different from the control sample. It has been established that the length of the sprouts increases when the concentration of diazinon increases. Diazinon does not have toxicity to seeds, and enhances their growth and development. In an experiment to establish the effects of the insecticide on soil bacteria, it was found that in soil, untreated toxicant, the dominant microorganisms are Pseudomonas sp., Bacillus sp., Arthrobacter sp., Azotobacter sp. and Azotobacter sp. and Flavobacterium sp. When the concentration of the substance of the drug (PC, 2PC, 5 PC) increases, there is a change in the quality and quantitative composition of soil microorganisms. The decrease in the number of microorganisms occurs already during the production concentration. 2 PC pollution of leads to the disappearance from the microenvironment of the soil Azotobacter sp., Arthrobacter sp. and Flavobacterium sp. Toxic action of diazinon is sustained by bacteria of the species Pseudomonas sp. and Bacillus sp. Biodestruction of the diazinon was carried out for 65 days. After 14 days in the NMR and GLC-MS spectrums products of hydralise diazinone appeared. The complete chemical transformation of the studied pesticide takes place on 65 days (control on TLH), in the NMR 31P spectrum there are no signals of the phosphorus atom. At the same time, there is no diazinone in the GLC-MS spectrum, but there has been a peak identified as 4.6- dimethyl-N-phenylpiridin-2-amin, which can be considered as a biodegradation product under the influence of Pseudomonas sp. bacteria.

Soil microorganisms' carbon transformation test for Picoxystrobin 25% SC (w/v) in loamy sand soil

The effect of Picoxystrobin 25% SC on soil microorganisms (carbon transformation) was assessed in a test that measured induced respiration rate following the application of Picoxystrobin 25% SC to soil. Picoxystrobin 25% SC was incubated in loamy sand soil over a period of 28days for the carbon turnover at 1-fold and 5-fold concentrations, equivalent to 0.340mg/kg dry weight (T1) and 1.700mg/kg dry weight (T2) on product basis, respectively (corresponding to a field application rates of 400mL/ha and 2000mL/ha). Control consists of soil treated with equivalent quantity of distilled water and it was also incubated in the dark along with the treated soil samples. Carbon transformation was determined by short term respiration of soil microorganisms by amending soil samples with glucose. The oxygen consumption (BOD) during short term respiration of soil microorganisms in soil samples was measured up to 12 consecutive hours following addition of glucose on days 0, 7, 14 and 28 after application of Picoxystrobin 25% SC. In loamy sand soil respiration study at the end of the 28th day, deviations in respiration rates compared to controls after applying the test item to soil were −18.34% and −19.55% for the test concentrations of 0.340mg and 1.700mg of Picoxystrobin/kg soil dry weight, respectively. The dose concentrations (T1 and T2 levels) of Picoxystrobin 25% SC ware determined by validated HPLC method.

Total Colony Counts of Some Microorganisms in Soil Samples Exposed To Electromagnetic Radiations from Mobile Phones

Effect of electromagnetic radiations (EMR) from mobile phones on some soil bacterial ( Bacillus, Micrococcus, Staphylococcus, Corynebacterium and Enterococcus) and fungi ( Saccharomyces, Penicillium and Geotrichum) strains were studied. At the study periods of 0, 30, 60, and 90 days, the total colony counts (CFU/g) and viability ratios of Bacteria and fungi strains were determined on both the EMR unexposed and exposed soil samples. At the exposure per iods of 30, 60, and 90 days, the mean total colony counts of all the organisms in the EMR exposed samples were statistically (p<0.05) lower than those of the EMR unexposed samples. The percentage changes in total colony counts of the EMR unexposed and expo sed soil samples between 0 to 90 days for Bacillus, Micrococcus, Staphylococcus, Corynebacterium, Enterococcus, Saccharomyces, Penicillium and Geotrichum were 2.54% and - 70.51%, 33.18% and - 75.80%, 11.79% and - 63.93%, 20.12% and - 91.96%, 30.00% and - 98.94% , 62.36% and - 61.06%, 42.40% and - 100%, and

Diffuse hydrothermal methane output and evidence of methanotrophic activity within the soils at Sousaki (Greece)

Methane soil flux measurements have been made in 38 sites at the geothermal system of Sousaki (Greece) with the closed chamber method. Fluxes range from )47.6 to 29 150 mg m day, and the diffuse CH4 output of the system has been estimated at 19 t a. Contemporaneous CO2 flux measurements showed a moderate positive correlation between CO2 and CH4 fluxes. Comparison of the CO2 ⁄CH4 soil flux ratios with the CO2 ⁄CH4 ratio of the gases of the main gas manifestations provided evidence for methanotrophic activity within the soil. Laboratory CH4 consumption experiments confirmed the presence of methanotrophic microorganisms in soil samples collected at Sousaki. Consumption was generally in the range from )4.9 to )38.9 pmolCH4 h )1 g but could sometimes reach extremely high values ()33 000 pmolCH4 h )1 g). These results are consistent with recent studies on other geothermal systems that revealed the existence of thermoacidophilic bacteria exerting methanotrophic activity in hot, acid soils, thereby reducing methane emissions to the atmosphere.

Drug Development from Natural Fermentation Products: Establishing a Manufacturing Process Which Maximizes the Potential of Microorganisms

Natural fermentation products have long been studied as attractive targets for drug discovery due to their amazing diverse, complex chemical structures and biological activities. As such, a number of revolutionary drugs developed from natural fermentation products have contributed to global human health. To commercialize a drug derived from natural fermentation products, an effective chemical entity must be identified and thoroughly researched, and an effective manufacturing process to prepare a commercial supply must be developed. To construct such a manufacturing process for tacrolimus and micafungin, the following studies were conducted: first, we focused on controlling the production of the tacrolimus-related compound FR900525, a fermentation by-product of tacrolimus which was critical for quality assurance of the drug substance. FR900525 production was reduced by using a mutant strain which produced more pipecolic acid, the biosynthesis material of tacrolimus, than the original strain. Then, to optimize the fermentation process of FR901379, an intermediate of micafungin, a fed-batch culture was adopted to increase FR901379 productivity. Additionally, FULLZONE(TM) impeller was installed into the scaled-up fermenter, reducing the agitation-induced damage to the mycelium. As a result, the mycelial form changed from filamentous to pellet-shaped, and the air uptake rate during fermentation was drastically improved. Finally, we conducted screening for FR901379 acylase-producing microorganisms, as FR901379 acylase is necessary to manufacture micafungin. We were able to easily discover FR901379 acylase-producing microorganisms in soil samples using our novel, convenient screening method, which involves comparing the difference in antibiotic activity between FR901379 and its deacylated product.

Incorporating variations in pesticide catabolic activity into a GIS-based groundwater risk assessment

The catabolic activity of incumbent microorganisms in soil samples of eleven dissimilar soil series was investigated, with respect to the herbicide isoproturon. Soils were collected from a 30 × 37 km area of river catchment to the north-west of London, England. Catabolic activity in each soil type during a 500 h assay was determined by 14C-radiorespirometry. Results showed four soils that exhibited high levels of catabolic activity (33–44% mineralisation) while the remaining seven soils showed lower levels of catabolic activity (12–16% mineralisation). There was evidence to suggest that soils exhibiting high catabolic activity had low (< 22%) clay content and tended towards lower organic carbon content (< 2.7%), but that these higher levels of catabolic activity were also related to pre-exposure to isoproturon. The 14C-radiorespirometric results were used to produce a GIS layer representing levels of catabolic activity for the dissimilar soils across the study area. This layer was combined with other GIS layers relating to pesticide attenuation, including soil organic carbon content, depth to groundwater and hydrogeology, to produce a map showing risk of groundwater contamination by isoproturon. The output from this approach was compared with output from an attenuation-only approach and differences appraised. Inclusion of the catabolism layer resulted in a lowering of risk in the model in 15% of the study area. Although there appears to be limited benefit in including pesticide catabolic activity in this regional-scale groundwater risk model, this type of addition could be useful in a site-specific risk assessment.

Characterisation of Collagenolytic Enzymes Produced by Thermophylic Actinomycetes

ABSTRACTThe aim of the present investigation was to characterize enzymes, produced by extremophilic microorganisms in soil samples, collected from different regions in Bulgaria. The cultivation conditions for obtaining high yield of collagenolytic activity were optimized for two active strains—A 35 and E 15. The molecular mass of the active fractions in the cultural liquid of both strains was determined by means of gel chromatography on Sephadex G-100 and were in the range from 40 to 140 kDa. The proteolytic enzymes were stable against high ethanol concentrations, which allows an effective elimination of different byproducts (pigments, nutrient medium components and metabolites). The electrophoretic patterns show a certain isomorphism of the fractions. The comparison with clostridiopeptidase A, as well as the inhibitory analysis show that these enzymes might be considered as “collagenase-like” enzymes. Preliminary experiments show that they could be applied for pre-treatment of collagen-rich raw materials, e.g. in the pelt industry.

Determinação do número mais provável de microrganismos do solo pelo método de plaqueamento por gotas

A determinação do número mais provável (NMP) de fungos e bactérias do solo foi realizada pelo método de plaqueamento por gotas, por meio do qual foi possível economizar meio de cultura e trabalho. O método foi apresentado e comparado com o procedimento convencional de contagem de microrganismos do solo em amostras de solo de diferentes texturas. A sensibilidade desse método foi também observada em experimentos para contagem de microrganismos quando da adição de diferentes fontes de matéria orgânica e de sais de crômio.

Microcalorimetric study of some Amazonian soils

Microcalorimetric method was applied to study some Amazonian soils in order to establish the way by which the microbial soil activity is affected by the actual deforestation and burning suffered by the Amazonian rain forest. Different soil samples were collected in the Amazonian State of Brazil. Places with autochthonal vegetation and places that which had been deforested or burnt were elected due to its use in agriculture and cattle raising in an attempt to explore the difference in microbial growth behaviour. An LKB 2277 heat-flow microcalorimeter was used for all measurements at 298.15±0.02 K. The microcalorimetric data are presented together with some other measurements such as the physicochemical parameters and the number of microorganisms in soil samples. Power–time curves recorded from soil samples amended with the same quantity of glucose showed significant differences among soils used in the study. Results obtained were systematically studied in a more quantitative way and the values of the microbial growth rate constant, μ, total thermal effect, Q T , and duration of the peak-time, PT, were calculated from power–time curves. The collected data showed again important differences in the microbial activity among the soil samples suggesting that the native microbial activity of soils in tropical rain forests are dramatically affected by the deforestation and burning.

Quantitative flow cytometric detection of specific microorganisms in soil samples using rRNA targeted fluorescent probes and ethidium bromide.

Specific detection and accurate enumeration of microorganisms in the environment have been hampered by the lack of suitable techniques. A three-parameter flow cytometric method (FCM) was developed to detect quantitatively Sphingomonas sp. strain 107 inoculated into soil samples. By combining light scattering profiles (i.e., morphological properties), ethidium bromide (EtBr) influx (i.e., wall permeability), and fluorescence in situ hybridization against the 16S rRNA (i.e., detection specificity), we could accurately discriminate the bacterium of interest from the indigenous microflora and soil debris. EtBr was used, first, to determine the optimal cell wall permeabilization treatment to allow oligonucleotide probes to enter the bacterial cells and, second, to achieve clear discrimination of fixed cells from debris in soil samples. This method allowed effective qualitative and quantitative analysis by fluorescence in situ hybridization. The results showed that the detection threshold by FCM was 3 x 10(4) cells/g of dry soil. Cell counts deduced from FCM analysis were similar to those obtained by the colony forming unit assay when soils contained fewer than 3 x 106 cells/g dry soil. This method should be useful for either quantitative monitoring of microorganisms inoculated in contaminated soil samples during bioremediation or detecting known bacterial strains in environmental samples.

Fate of Dissolved Toluene during Steady Infiltration through Unsaturated Soil: I. Method Emphasizing Chloroform as a Volatile, Sorptive, and Recalcitrant Tracer

AbstractChloroform can be used as a volatile, sorptive, and recalcitrant tracer compound relative to volatile and transformable organic compounds, such as toluene, in aerobic unsaturated soil column experiments. Chloroform concentrations &lt;4 mg/L did not affect the rate of toluene oxidation and chloroform itself was not transformed aerobically. In the current experiments, chloroform was applied at lower concentrations than the degradable compound. Chloroform was used to estimate the column mass balance without degradation so that mass loss for the degradable compound in the column could be confidently attributed to transformation. Consistent numbers of viable heterotrophic microorganisms in soil samples from column experiments with and without chloroform added suggest that the added chloroform did not have a negative effect on the soil microorganism population.

Effect of alder(Alnus glutinosaL. Gaertn.) roots on distribution of proteolytic, ammonifying, and nitrifying bacteria in soil

The aim of this study was to determine the main factor affecting mineralizing and nitrifying bacteria in a riparian bank, where alder ( Alnus glutinosa L. Gaertn., diazotrophic plant), willow (Salix alba L.) and poplar (Populus × hybrida Moench 1–214) were the main species of vegetation. This was investigated by estimating the most probable number of microorganisms in soil samples from roots collected in spring, summer, autumn, and winter. The numbers of the total microbial population and the ammonifying and proteolytic microorganisms were higher in the plant rhizosphere and rhizoplane than in the shaded soil, litter, and root‐free soil under the trees. Nitrifier densities were the lowest around alder roots. Principal components analysis showed that the main factor affecting microorganism density was the rhizosphere of alder trees. Our results suggest that roots favor microorganism colonization (proteolytic and ammonifying microorganisms) and that roots, particularly alder roots, inhibit nitrifying microorganisms.

Microbial Ecology of Constructed Wetlands Used for Treating Pulp Mill Wastewater

Objectives were to evaluate microbial populations in two free-water surface (FWS) constructed wetland cells receiving secondary treated pulp-mill wastewater, identify the microorganisms having decomposition activity of selected organic substances and discuss diversity of actinomycetes isolated from soil, plant and wastewater samples. The populations of microorganisms in soil samples in the two wetland cells showed similar size in both cells; 6–7 × 106 cfu/g, 0.7–1.0 × 106 cfu/g, and 0.8–1.0 × 104 cfu/g, respectively, for total bacteria, actinomycetes and fungi. The population of bacteria in wastewater was similar in size to bacteria isolated from soil, but those of actinomycetes and fungi exhibited a very small size: 2–3 × 103 cfu/ml and only about 10 cfu/ml, respectively. In the populations on the surface of bulrush stems, the number of bacteria, actinomycetes and fungi found on the top portion of the stems was 4 × 105 cfu/cm2, 1.4 × 103 cfu/cm2 and 0.5 × 102 cfu/cm2, respectively. Actinomycetes and fungi occurred in very low numbers on the bottom of stems. More than 90% of actinomycetes isolated from the wetland cells had amylase activity, and 60 and 25% of them had chitinase and xylanase activity, respectively. Approximately 70 and 50% of fungi had protease and amylase activities, respectively. Fungi also had xylanase activity in about 40% of isolates. On the other hand, about 40% of bacteria exhibited protease activity, but a very low proportion of them had chitinase and xylanase activities. The number of actinomycete species isolated from wastewater and the surface of plant stems was restricted in comparison to that of actinomycetes isolated from soil.

Distribution of poly(?-hydroxybutyrate) and poly(?-caprolactone)aerobic degrading microorganisms in different environments

To assess the capacity of the natural environment for degrading plastics, the populations of poly(β-hydroxybutyrate)(PHB)-and poly(e-caprolactone)(PCL)-degrading aerobic microorganisms and their ratios to the total number of microorganisms in soil samples were estimated by the plate count method with agar medium containing emulsified PHB or PCL. The numbers of the degrading microorganisms were determined by counting colonies that formed clear zones on the plate. It was found that PHB- and PCL-degrading (depolymerizing) microorganisms are distributed over many kinds of material, including landfill leachate, compost, sewage sludge, forest soil, farm soil, paddy soil, weed field soil, roadside sand, and pond sediment. Of total colony counts, the percentages of PHB and PCL degrading microorganisms were 0.2–11.4 and 0.8–11.0%, respectively. The results suggest that many kinds of degrading microorganisms are present in each environment and that specific consortia differing in biodegradation capacity are constructed.