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TWENTY FIVE Aspergillus isolates were screened from Giza Governorate and Saint Catherine Protectorate soils in Egypt. The antimicrobial activity of the crude extracts was tested against two Gram positive bacteria (Bacillus subtilis NRRL-B-4219, Staphylococcus aureus ATCC29213), four Gram negative bacteria (Alcaligenes faecalis B-170, Escherichia coli ATCC25922, Klebsiella pneumoniae ATCC10131, Pseudomonas aeruginosa ATCC27953), and one yeast (Candida albicans ATCC10231). The antioxidant activity using free radical scavenging model was assayed for the crude extracts. The antitumor activity for all of crude extracts was determined against HCT116 (Colon carcinoma cell line), HEPG2 (Liver carcinoma cell line), and MCF-7 (Breast carcinoma cell line). Aspergillus nomius was the most potent fungal species accordingly, it was chosen for bioactivity assay. Identification of this species was further confirmed at the molecular level based on nuclear ribosomal DNA 18s identities. An accession number, LC199488, was given at the DDBJ GenBank. The column chromatography of its crude extract yielded five distinguished fractions. The biological (antimicrobial, antioxidant and antitumor) activities of these fractions were assayed. Fraction B proved to be of most potential. HPLC analysis of this fraction showed that there was a sharp and clear peak at about 18.1 min. This denoted the presence of an active compound. The compound at this peak was purified and its structure was elucidated via 1HNMR and 13CNMR spectroscopy. It was concluded that it would be 1,2,3,9 tetrahydropyrrolo [2,1-b] quinazolin-3-ol.

Acinetobacter baumannii (A. baumannii) is widely known as an opportunistic bacterial pathogen that causes infection more frequently among immunocompromised individuals. Our case demonstrated the limitation of the current VITEK 2 system for the idendification of A. baumannii. Four clinical isolates of A. baumannii were identified as Alcaligenes faecalis by the VITEK 2 system. Misidentification might lead to unnecessary tests and inappropriate treatments. Additional methods appear to be helpful for the accurate identification of A. baumannii for clinical microbiology laboratories.

Two genes encoding nitrilases with different properties have been found in an Alcaligenes denitrificans C-32 strain with high nitrilase activity that is currently used as a biocatalyst for commercial ammonium acrylate production. Both genes were expressed in E. coli, and the properties of the recombinant nitrilases were studied. One of these genes, which is designated as nitC1, controlled the formation of nitrilase that preferred aliphatic nitriles (acrylonitrile and butyronitrile) as best substrates. The nucleotide sequence of the gene nitC1 was almost (99%) identical to the gene sequence of an aliphatic nitrilase from Acidovorax facilis 72W (DQ4444267). In turn, nitC2 had a high level of homology (85%) with the arylacetonitrilase gene from Alcaligenes faecalis JM3 (D13419). Benzyl cyanide was shown to be the best substrate for nitC2-encoded nitrilase. In light of the results of DNA homology and differences in substrate specificity, the NitC2 and NitC1 nitrilases from Alcaligenes denitrificans C-32 were allocated to the groups of aliphatic nitrilases and arylacetonitrilases, respectively.

Silver nanoparticles have attracted much attention due to their potential applications in biomedical fields. In this study, silver nanoparticles (PAgNPs) were first synthesized using crude polysaccharides from Psidium guajava L. leaf (CP-PGL). The synthesized PAgNPs were characterized using several instrumental techniques and were regular spheres with an average size of 25–35 nm and a maximum absorbance at 435 nm. The results indicated that CP-PGL contains potential reducing agents for the rapid synthesis of benign and stable nanoparticles. Moreover, PAgNPs exhibited a high radical scavenging activity for DPPH and ABTS + as well as strong inhibition against five selected bacteria, especially Alcaligenes faecalis and Escherichia coli . The current study revealed that biosynthesis of PAgNPs with polysaccharides can be potentially applied to produce an antioxidant or antimicrobial agent for use in biomedical and cosmetic products.

The potential and mechanism of synthesized magnetic octahedral molecular sieve (Fe3O4@OMS-2) nanoparticles in enhancing the aerobic microbial ability of sequencing batch reactor (SBR) for treating dye wastewater have been revealed in this study. The addition of Fe3O4@OMS-2 of 0.25 g/L enhanced the decolorization of SBRs with an operation cycle of 24 h by more than 20%. The 16S rRNA gene high-throughput sequencing indicated Fe3O4@OMS-2 increased the microbial richness and diversity of SBRs, and more importantly, promoted the potential dye-degrading bacteria. After a series of enriching and screening, four bacterial strains with the considerable decolorizing ability were isolated from SBRs, designating Alcaligenes faecalis FP-G1, Bacillus aryabhattai FP-F1, Escherichia fergusonii FP-D1 and Rhodococcus ruber FP-E1, respectively. The growth and decolorization of these pure strains were promoted in the presence of Fe3O4@OMS-2, which agrees with the result of high-throughput sequencing. Monitoring dissolved Fe/Mn ions and investigating the change of oxidation states of Fe/Mn species discovered OMS-2 composition played the critical role in modulating the microbial community. The significant enhancement of Mn-oxidizing/-reducing bacteria suggested microbial Mn redox may be the key action mechanism of Fe3O4@OMS-2, which can provide numerous benefits for the microbial community and decolorization of SBRs.

A heterogeneous biocatalyst for the biotransformation of nitriles and amides of carboxylic acids in the form of cells of nitrile-hydrolyzing bacteria immobilized on the carrier, was created based on multiwalled carbon nanotubes (MWCNTs). It was shown that bacterial cells form aggregates in contact with powderformed purified or unpurified MWCNTs. The amount of both gram-positive and gram-negative bacteria binding with unpurified MWCNTs was significantly higher than with purified. The nitrile hydratase and amidase activity of bacterial aggregates of purified MWCNTs was preserved to a greater extent as compared to that of unpurified MWCNTs and cells adhered to the surface of the carbonized pyrosealing material with MWCNTs. Both gram-positive Rhodococcus ruber gt1 and gram-negative Alcaligenes faecalis 2 remained viable when cultured in the presence of purified or unpurified MWCNTs. The obtained heterogeneous biocatalyst can be easily separated from the medium by filtration and can be used repeatedly.

AIMS: The aim of this study is to report on the hydrolytic action of Alcaligenes faecalis isolated from soil samples and its ability to degrade ochratoxin A. METHODS AND RESULTS: An A. faecalis strain was identified and characterized by employing both a phenotypic analysis and 16S rDNA sequence analysis. The results show that this strain could degrade ochratoxin A efficiently but could not use it as a sole carbon source. Ochratoxin α was confirmed as a degradation product in the intracellular extract of A. faecalis using UPLC‐MS/MS. Our results suggest that the biodegradation of ochratoxin A by the A. faecalis strain occurs through the hydrolysis of the ochratoxin A amide bond by a putative peptidase. This is the first report to date on the degradation of ochratoxin A by A. faecalis. CONCLUSION: The A. faecalis strain is presumably a suitable candidate for use in the biodegradation of ochratoxin A. SIGNIFICANCE AND IMPACT OF THE STUDY: Ochratoxin A, which is produced by some filamentous fungi, severely impacts human and animal health by contaminating several types of food and feed. Our study contributes to the identification of the function of A. faecalis 0D‐1, which is capable of producing hydrolytic enzyme(s) to biodegrade ochratoxin A into nontoxic ochratoxin α, to minimize the risk associated with ochratoxin A exposure.

Hydrocarbons degrading bacteria were isolated from sediments of the Soummam watershed of Bejaia (Algeria). Eleven bacteria strains were isolated using an enrichment technique, method in mineral salt medium, with various hydrocarbons as the sole carbon source. The biodegradation confirmation of various hydrocarbons by these isolates was tested by hole-plate diffusion technique. Out of eleven cultures, nine had shown the growth around the holes. The isolates were screened for biosurfactant producing using oil spreading test and emulsification activity. The value of emulsification activity varied from 55.7 ± 1.1 to 78.5 ± 0.5%. The diameter of clear zone obtained varied between 20.7 ± 1.2 mm and 33.7 ± 1.2 mm, it was hence important compared to the negative control. Five bacterial strains were identified as Alcaligenes faecalis, Ochrobactrum, Cellulosimicrobium, Pseudomonas stutzeri, and Rhodococcus ruber by using physiochemical characterization and MALDI-TOF mass spectrometry tools. The best production of crude biosurfactant by the identified bacterial strains was found in R. ruber which produced 6.7 ± 0.1 g/L of the crude biosurfactant after 168 h incubation in mineral salt medium (MSM) supplemented with 2% of glucose and 0.1 g/L of yeast extract. The biosurfactant produced by all bacterial strains showed a high emulsification index (E24), where P. stutzeri revealed the highest one (92.2 ± 1.1%). © 2017 American Institute of Chemical Engineers Environ Prog, 2017

Solvent extracts of Mazus japonicus and Fumaria indica were investigated individually and in combinations (1:1, 1:2, or 2:1) for their antibacterial potency against Bacillus subtilis, Pseudomonas geniculata, Streptomyces laurentii, Klebsiella pneumoniae, Microbacterium oxydans, Alcaligenes faecalis, and Enterococcus faecium. Minimum inhibition concentration (MIC) and fractional inhibitory concentration (FIC) were investigated. Petroleum ether extracts showed moderate (6.06 mg.mL–1 MIC for M. japonicus and 1.65 mg.mL–1 MIC for F. indica), aqueous extract had the lowest, 1.619 mg.mL–1 MIC for M. japonicus and18.36 mg.mL–1 MIC of F. indica), and methanolic extract showed the highest (0.740 mg.mL–1 MIC for M. japonicus and 1.065 mg.mL–1 MIC for F. indica) antibacterial activities (individual analysis). When analyzing mixtures, none of the aqueous extracts showed synergistic effect against any bacteria. Methanolic extract mixtures demonstrated synergy against B. subtilis (0.082 mg.mL–1 MIC with 2:1); t...

Polycyclic aromatic hydrocarbons (PAHs) in soil retain for a quite long period due to their hydrophobicity and aggregation properties. Biofilm-forming marine bacterial consortium (named as NCPR), composed of Stenotrophomonas acidaminiphila NCW702, Alcaligenes faecalis NCW402, Pseudomonas mendocina NR802, Pseudomonas aeruginosa N6P6, and Pseudomonas pseudoalcaligenes NP103, was used for the bioremediation of PAHs in a soil microcosm. Phenanthrene and pyrene were used as reference PAHs. Parameters that can affect PAH degradation, such as chemotaxis, solubility of PAHs in extracellular polymeric substances (EPS), and catechol 2,3-dioxygenase (C23O) activity, were evaluated. P. aeruginosa N6P6 and P. pseudoalcaligenes NP103 showed chemotactic movement towards both the reference PAHs. The solubility of both the PAHs was increased with an increase in EPS concentration (extracted from all the 5 selected isolates). Significantly (P < 0.001) high phenanthrene (70.29%) and pyrene (55.54%) degradation was observed in the bioaugmented soil microcosm. The C23O enzyme activity was significantly (P < 0.05) higher in the bioaugmented soil microcosm with phenanthrene added at 173.26 ± 2.06 nmol min−1 mg−1 protein than with pyrene added at 61.80 ± 2.20 nmol min−1 mg−1 protein. The C23O activity and gas chromatography-mass spectrometer analyses indicated catechol pathway of phenanthrene metabolism. However, the metabolites obtained from the soil microcosm added with pyrene revealed both the catechol and phthalate pathways for pyrene degradation.

Contamination of the environment by heavy metals has been increasing in recent years due to industrial activities. Thus research involving microorganisms capable of surviving in multi-contaminated environments is extremely important. The objectives of the present study were to evaluate the removal of mercury alone and in the presence of cadmium, nickel and lead by four mercury-resistant microorganisms; estimate the removal of Cd, Ni and Pb; understand the mechanisms involved (reduction, siderophores, biofilms, biosorption and bioaccumulation) in the metal resistance of the isolate Pseudomonas sp. B50D; and determine the capacity of Pseudomonas sp. B50D in removing Hg, Cd, Ni and Pb from an industrial effluent. It was shown that the four isolates evaluated were capable of removing from 62% to 95% of mercury from a culture medium with no addition of other metals. The isolate Pseudomonas sp. B50D showed the best performance in the removal of mercury when evaluated concomitantly with other metals. This isolate was capable of removing 75% of Hg in the presence of Cd and 91% in the presence of Ni and Pb. With respect to the other metals it removed 60%, 15% and 85% of Cd, Ni and Pb, respectively. In tests with effluent, the isolate Pseudomonas sp. B50D removed 85% of Hg but did not remove the other metals. This isolate presented reduction, biosorption, biofilm production and siderophore production as its metal resistance mechanisms. Pseudomonas sp. B50D was thus a candidate with potential for application in the bioremediation of effluents with complex metal contaminations.

Folia microbiologica 62(6), 453-461 (2017). doi:10.1007/s12223-017-0516-9, Published by Springer, [S.l.]

Carbapenemase-producing Alcaligenes species has been described in only few studies, with none so far from the African continent. Here, we report the whole genome sequence of Peanalcaligenes suwonensis bearing bla

Tebuconazole is a widely used fungicide that may impair soil health. Presently, limited information is available on the bioremediation of tebuconazole-contaminated soil using biochar as a carrier for bacteria. In this study, we firstly isolated a tebuconazole-degrading strain and identified it as Alcaligenes faecalis WZ-2. Then, we used wheat straw-derived biochar as carrier to capture strain WZ-2 to assemble microorganism-immobilized composite. Finally, we investigated the effects of strain WZ-2 and biochar-immobilized WZ-2 on tebuconazole biodegradation, microbial enzyme activities and community composition in the contaminated soil. Results showed that, as compared to control, the strain WZ-2 and biochar-immobilized WZ-2 accelerated the degradation of tebuconazole, while reducing the half-life of tebuconazole from 40.8 to 18.7 and 13.3 days in soil, respectively. However, biochar alone than control slightly retarded the degradation of tebuconazole in soil. Though tebuconazole (10 mg/kg) negatively affected the soil enzyme activities (urease, dehydrogenase, and invertase) and microbiome community structure, the biochar-immobilized WZ-2 not only accelerated the degradation of tebuconazole but also restored native soil microbial enzyme activities and microbiome community composition. Our results suggest that a compatible combination of bacteria with biochar is an attractive and efficient approach for remediation of pesticide-contaminated soil and improvement of soil biological health.

Background: Diabetic foot ulcers are an increasingly common complex problem and are associated with a very considerable health care burden. Diabetic foot ulcer with Alcaligenes faecalis infection is rarely reported in the literature. We report a case series of diabetic foot ulcer with Alcaligenes faecalis infection treated at our facility. Methods: We conducted a retrospective analysis of all patients with diabetic foot ulcer with Alcaligenes faecalis infection seen from January 2014 to April 2019. We analyzed the clinical characteristics, ulcer lesion classification, comorbidities, prior intravenous antibiotic use within three months, wound culture, antibiotics sensitivity test, and clinical outcomes of these patients. Results: Eight cases of diabetic foot ulcer with Alcaligenes faecalis infection were seen in five males and three females. The mean age was 54.6 years. All patients had other comorbidities, and all ulcer lesions were of chronic duration ( more than 14 days ). All wound cultures revealed polymicrobial infection, with two cases of diabetic foot with extensive-drug resistant Alcaligenes faecalis infection found in 2019. All patients needed intravenous antibiotic therapy and surgical interventions for the chronic ulcer lesion. The wound failed to heal in three patients. Conclusions: All diabetic foot ulcers with Alcaligenes faecalis infection were of chronic duration ( more than 14 days ) and had polymicrobial infection. Extensive-drug resistant Alcaligenes faecalis emerged in 2019. Definitive antibiotic therapy is necessary for all infected wounds and should be based on both the culture results and susceptibility data. All patients will need appropriate wound care, and most will need rapid surgical intervention for an optimal outcome.

A laccase producing new bacterial strain (Alcaligenes faecalis XF1) was isolated from green site of Chandigarh (India) by standard screening method. Nutrient broth medium containing 0.2 mM CuSO4 was used for the production of laccase. Maximum production (110 U/ml) was achieved after four days of incubation. The extracellular laccase from the medium was purified by simple salt precipitation and ion exchange technique to get 3.8 fold purified protein with 1637.8 U/mg specific activity. Purified laccase (named as LAC1*) revealed its optimum activity at pH 8.0 and 80 °C temperature, and displayed remarkable stability in the range of 70–90 °C and in the pH range (pH 7.0–9.0). The single bands on SDS-PAGE represents the purity of LAC1* with molecular weight of ∼71 kDa. The kinetic parameters for 2,6-DMP oxidation was Km, Vmax and kcat were 480 μM, 110 U/mL and 1375 s−1. Enzyme activity of the LAC1* was significantly enhanced by Cu2+, Mg2+, Mn2+, SDS and NaCl, and was slightly inhibited in the presence of conventional inhibitors like cysteine, EDTA and sodium azide. Extracellular nature and significant stability of LAC1* under extreme conditions of temperature, pH, heavy metals, halides and detergents confined its suitability for various biotechnological and industrial applications which required these qualities of laccase. So after recognizing all these properties the purified laccase was studied for its application in decolorization of industrial dyes. Keywords: Laccase, Alcaligenes faecalis, Decolorization

In this study, simultaneous removal of ammonium plus phenol could be achieved by Alcaligenes faecalis strain WY-01 with the addition of acetate, although acetate delayed the phenol degradation, probably due to the delayed expression of phenol hydroxylase gene under the presence of acetate. Moreover, the successful expression of key enzyme genes in strain WY-01 provided some evidence to illustrate its metabolic pathways of ammonium and phenol under aerobic conditions. Furthermore, SEM was used to clarify the role of acetate in resisting phenol toxicity, and these results demonstrated that strain WY-01 has the ability to form cell flocs when sodium acetate is used as co-substrate for a high concentration of phenol, and these flocs could protect cells against the toxicity of phenol, further enhancing phenol degradation in a high concentration of phenol. All these will provide further insights into the efficacy of strain WY-01 for treating wastewater cocontaminated by ammonium and phenol.

In this study, a bacterial strain exhibiting high selenite (Na₂SeO₃) tolerance and reduction capacity was isolated from the gut of

Carbapenemase-producing Alcaligenes species has been described in only few studies, with none so far from the African continent. Here, we report the whole genome sequence of Peanalcaligenes suwonensis bearing bla(VIM-5) metallo-beta-lactamase and first detection of carbapenemase producing Alcaligenes faecalis isolated from patients attending tertiary healthcare facilities in Nigeria. The isolates were identified by MALDI-TOF Mass Spectrometry. Antibiotic susceptibility assay, modified Carba NP test and genomic investigation revealed that two isolates of Alcaligenes faecalis and an isolate of Paenalcaligenes suwonensis harboured bla(VIM-5) gene. The genome sequence analysis of the P. suwonensis 191B isolate, responsible for acute gastroenteritis, reveal the presence of 18 antibiotic resistance genes coding for resistance to five different classes of antibiotics. Three of the genes (bla(OXA-368), bla(CARB-4) and bla(VIM-5)) codes for resistance to beta-lactam antibiotics. To our best knowledge, we describe here the first genome sequence of P. suwonensis species and the first detection of class B carbapenemase bla(VIM-5) in a clinical isolate of P. suwonensis species and Alcaligenes faecalis in Nigeria. The finding of this study is of concern, as lateral dissemination of the genes into clinically important Gram-negative pathogens is highly likely.

Coke oven wastewater produced from steel industry contains hazardous constituents like phenols, cyanides, ammonia, SCN−, etc., which needs to be treated before expulsion to the environment. Therefore, pre-treatment of these large volume of wastewater is required for maintaining environmental standards. Simulated coke oven wastewater pertaining to effluent characteristics discharged by industrial sector was synthesized. Initially, treatment of wastewater was performed with ozone which was used in combination with activated carbon (AC) and H2O2 to increase the degradation of COD. The maximum degradation achieved in the O3/AC was 76.8% while in with O3/H2O2, the COD removal was 75.8%. The O3/AC process was found more acceptable in terms of fast rate of COD degradation, time and economy efficiency suitable for handling large volume of wastewater. However, problems of sludge disposal and process hazards diverted the adoption towards microbial treatment using bacterial strain Alcaligenes faecalis JF339228 where phenol was degraded up to 80.88% in 76 h from the coke oven mixture. Due to the high toxicity level of coke oven wastewater, only biological treatment fails to treat them effectively. Combined microbial treatment as well as membrane-based separation process (thin-film composite—reverse osmosis membrane) for wastewater purification was also applied. Thin-film composite (TFC) RO membrane was used to treat this solution at pressure of 200 and 300 psi and at different pH of 5, 7 and 8, respectively. The maximum quantity of phenol removed by TFC RO membrane at 300 psi pressure and pH of 8 was 76%. Thus, an amalgamated approach of bioremediation and reverse osmosis was sustainable.

Made available in DSpace on 2021-06-25T10:44:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01 Here we present and analyze the complete genome of Alcaligenes faecalis strain Mc250 (Mc250), a bacterium isolated from the roots of Mimosa calodendron, an endemic plant growing in ferruginous rupestrian grasslands in Minas Gerais State, Brazil. The genome has 4,159,911 bp and 3,719 predicted protein-coding genes, in a single chromosome. Comparison of the Mc250 genome with 36 other Alcaligenes faecalis genomes revealed that there is considerable gene content variation among these strains, with the core genome representing only 39% of the protein-coding gene repertoire of Mc250. Mc250 encodes a complete denitrification pathway, a network of pathways associated with phenolic compounds degradation, and genes associated with HCN and siderophores synthesis; we also found a repertoire of genes associated with metal internalization and metabolism, sulfate/sulfonate and cysteine metabolism, oxidative stress and DNA repair. These findings reveal the genomic basis for the adaptation of this bacterium to the harsh environmental conditions from where it was isolated. Gene clusters associated with ectoine, terpene, resorcinol, and emulsan biosynthesis that can confer some competitive advantage were also found. Experimental results showed that Mc250 was able to reduce (∼60%) the virulence phenotype of the plant pathogen Xanthomonas citri subsp. citri when co-inoculated in Citrus sinensis, and was able to eradicate 98% of juveniles and stabilize the hatching rate of eggs to 4% in two species of agricultural nematodes. These results reveal biotechnological potential for the Mc250 strain and warrant its further investigation as a biocontrol and plant growth-promoting bacterium. Núcleo de Pesquisas em Ciências Biológicas (NUPEB) Universidade Federal de Ouro Preto Departamento de Ciências Biológicas (DECBI) Instituto de Ciências Exatas e Biológicas (ICEB) Universidade Federal de Ouro Preto (UFOP) Instituto Pristino Departamento de Bioquimica (DBQ) Instituto de Quimica (IQ) Universidade de São Paulo (USP) Instituto de Biotecnologia Aplicada a Agropecuária (BIOAGRO) Universidade Federal de Vicosa (UFV) Departamento de Tecnologia Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV) Universidade Estadual Paulista (UNESP) Faculdade de Computação (FACOM) Universidade Federal de Mato Grosso do Sul Departamento de Tecnologia Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV) Universidade Estadual Paulista (UNESP)

In this study, the mechanism for converting citrus peel wastes (CPW) into bioflocculants using Alcaligenes faecalis subsp. phenolicus ZY-16 was analysed. The results demonstrated that the ZY-16 strain could produce various lignocellulolytic enzymes, containing cellulase, hemicellulase, pectinase, protease, and ligninase, enhancing the hydrolysis of citrus peel wastes. Molecular distillation removes antimicrobial limonene, which could inhibit bioflocculant production. The optimal fermentation conditions with the highest bioflocculant yield (3.49 g/L) were 38.79 g/L of CPW, 35.54 °C, and pH 4.48. Furthermore, the bioflocculant was used to eliminate microcystins for the first time, and the highest removal efficiency (90.05%) was achieved at a pH of 3.0, after 800 mg/L of bioflocculant was added into the microcystins solution (10 mg/L) for 60 min. Therefore, this paper demonstrated that CPW could be a cost-effective feedstock for the production of bioflocculants, which have potential application in microcystin removal.

Rahma H, Nurbailis, Kristina N. 2019. Characterization and potential of plant growth-promoting rhizobacteria on rice seedling growth and the effect on Xanthomonas oryzae pv. oryzae. Biodiversitas 20: 3654-3661. Xanthomonas oryzae pv. oryzae (Xoo), a major limiting factor in rice production, and the use of resistant Xoo varieties have failed to control the bacterial pathogens as well as increased yield. It is due to the diversity in pathotypes, caused by environmental factors, the nature of resistant variety used, and gene mutation. The aims of this study were to select rhizobacterial strains with the potential of suppressing Xoo growth and promoting the growth of rice seedlings. This experiment was conducted in a completely randomized design (CRD) using seven rhizobacterial isolates selected through a dual culture test, with four replications. There were four isolates that potential in inhibiting the growth of Xoo, namely KJKB5.4, LMTSA5.4, Bacillus cereus AJ34, and Alcaligenes faecalis AJ14, with inhibition diameters greater than 11.50 mm. Rhizobacterial supernatant of 4 potential isolates has a zone of inhibition ranging from 12.25 to 24.00 mm. Four potential isolates were also able to solubilize phosphate, produce indole acetic acid (IAA) growth hormone, and siderophore, as well as enhance the growth of rice seedlings. Based on the nucleic acid sequencing of LMTSA5.4, KJKB5.4, and RK12 isolates were identified as Stenotrophomonas malthopilia strain LMG 958 (99.13%) accession NR 119220.1, Stenotrophomonas pavanii strain LMG 25348 (95.84%) accession NR 118008.1 and Ochrobactrum ciceri strain ca-34 (92.91%) accession NR115819.1.

Background and Objectives: Fibrinolytic drugs are commonly used for fibrin clot lysis but due to their inappropriate side effects, as well as their high costs, using fibrinolytic enzymes has been paid attention. Bacterial sources of this enzyme are a good alternative for this purpose. The aim was fibrinolysin production through screening of fibrinolysin producing bacteria from environmental samples. Materials and Methods: Bacterial isolation was performed from different environmental samples and was screened based on sheep blood clot digestion and culture on plasma plate. The most potent isolate was optimized for different growth parameters including temperature, pH and fibrinolysin production at optimum growth conditions. The stability of produced enzyme at various temperatures and pH and treatment with MgSO4, NiSO4, SDS and EDTA was then investigated. Finally this isolate was identified based on the 16S rRNA sequencing. Results: As a result, from 79 different isolates, the most potent fibrinolysin producer was identified as Alcaligenes faecalis strain 26. This isolate produced 12 mm halo zone on plasma plate. Its optimum growth temperature and pH was 43°C and 7, respectively. The produced enzyme had the best stability at pH 7 and was also active up to 60°C. The fibrinolytic activity of this isolate was reduced following treatment with MgSO4, NiSO4 and also with protease inhibitors, such as SDS and EDTA. Conclusion: Based on the obtained results it can be suggested that Alcaligenes faecalis strain 26 has appropriate efficiency for fibrinolysin production that can be used in food industry and medicine.