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1.
Braz. j. biol ; 83: e243874, 2023. graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1285606

ABSTRACT

Abstract In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.


Resumo Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.


Subject(s)
Bacillus/metabolism , Bacillus pumilus/metabolism , Sewage , Temperature , Dietary Fiber , Endo-1,4-beta Xylanases/metabolism , Fermentation , Hydrogen-Ion Concentration
2.
Braz. j. microbiol ; 49(3): 452-462, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951792

ABSTRACT

Abstract Exopolysaccharide (EPS) biopolymers produced by microorganisms play a crucial role in the environment such as health and bio-nanotechnology sectors, gelling agents in food and cosmetic industries in addition to bio-flocculants in the environmental sector as they are degradable, nontoxic. This study focuses on the improvement of EPS production through manipulation of different culture and environmental conditions using response surface methodology (RSM). Plackett-Burman design indicated that; molasses, yeast extract and incubation temperature are the most effective parameters. Box-Behnken RSM indicated that; the optimum concentration for each parameter was 12% (w/v) for molasses, 6 g/L yeast extract and 30 °C for incubation temperature. The most potent bacterial isolate was identified as Bacillus velezensis KY498625. After production, EPS was extracted, purified using DEAE-cellulose, identified using Fourier transform infrared (FTIR), gel permeation chromatography (GPC) and gas chromatography-mass spectroscopy (GC-MS). The result indicated that; it has molecular weight 1.14 × 105 D consisting of glucose, mannose and galactose.


Subject(s)
Polysaccharides, Bacterial/metabolism , Bacillus/metabolism , Polysaccharides, Bacterial/isolation & purification , Polysaccharides, Bacterial/chemistry , Bacillus/chemistry , Industrial Microbiology , Spectroscopy, Fourier Transform Infrared , Culture Media/metabolism , Culture Media/chemistry , Molecular Weight
3.
An. acad. bras. ciênc ; 90(1): 73-84, Mar. 2018. tab
Article in English | LILACS | ID: biblio-886885

ABSTRACT

ABSTRACT The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.


Subject(s)
Animals , Oligopeptides/pharmacology , Staphylococcus aureus/drug effects , Bacteriocins/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Bacillus/isolation & purification , Bacillus/metabolism , Bacteriocins/isolation & purification , Bacterial Adhesion/drug effects , Microbial Sensitivity Tests , Analysis of Variance
4.
Braz. j. microbiol ; 49(supl.1): 15-24, 2018. tab, graf
Article in English | LILACS | ID: biblio-974338

ABSTRACT

Abstract This study was aimed to investigate the effect of bio-organic phosphate either alone or in combination with phosphorus solubilizing bacteria strain (Bacillus MWT-14) on the growth and productivity of two wheat cultivars (Galaxy-2013 and Punjab-2011) along with recommended (150-100 NP kg ha−1) and half dose (75-50 NP kg ha−1) of fertilizers. The combined application of bio-organic phosphate and the phosphorous solubilizing bacteria strain at either fertilizer level significantly improved the growth, yield parameters and productivity of both wheat cultivars compared to non-inoculated control treatments. The cultivar Punjab-2011 produced the higher chlorophyll contents, crop growth rate, and the straw yield at half dose of NP fertilizer; while Galaxy-2013, with the combined application of bio-organic phosphate and phosphorous solubilizing bacteria under recommended NP fertilizer dose. Combined over both NP fertilizer levels, the combined use of bio-organic phosphate and phosphorous solubilizing bacteria enhanced the grain yield of cultivar Galaxy-2013 by 54.3% and that of cultivar Punjab-2011 by 83.3%. The combined application of bio-organic phosphate and phosphorous solubilizing bacteria also increased the population of phosphorous solubilizing bacteria, the soil organic matter and phosphorous contents in the soil. In conclusion, the combined application of bio-organic phosphate and phosphorous solubilizing bacteria offers an eco-friendly option to harvest the better wheat yield with low fertilizer input under arid climate.


Subject(s)
Phosphates/pharmacokinetics , Phosphorus/metabolism , Bacillus/metabolism , Triticum/growth & development , Fertilizers/analysis , Crop Production/methods , Phosphates/analysis , Phosphorus/analysis , Soil Microbiology , Triticum/metabolism , Triticum/microbiology , Climate
5.
Braz. j. microbiol ; 49(supl.1): 40-46, 2018. tab
Article in English | LILACS | ID: biblio-974339

ABSTRACT

Abstract Bacterial endophytes are considered to have a beneficial effect on host plants, improving their growth by different mechanisms. The objective of this study was to investigate the capacity of four endophytic Bacillus strains to solubilize iron phosphate (Fe-P), produce siderophores and indole-acetic acid (IAA) in vitro, and to evaluate their plant growth promotion ability in greenhouse conditions by inoculation into pearl millet cultivated in a P-deficient soils without P fertilization, with Araxá rock phosphate or soluble triple superphosphate. All strains solubilized Fe-P and three of them produced carboxylate-type siderophores and high levels of IAA in the presence of tryptophan. Positive effect of inoculation of some of these strains on shoot and root dry weight and the N P K content of plants cultivated in soil with no P fertilization might result from the synergistic combination of multiple plant growth promoting (PGP) traits. Specifically, while B1923 enhanced shoot and root dry weight and root N P content of plants cultivated with no P added, B2084 and B2088 strains showed positive performance on biomass production and accumulation of N P K in the shoot, indicating that they have higher potential to be microbial biofertilizer candidates for commercial applications in the absence of fertilization.


Subject(s)
Bacillus/metabolism , Food/metabolism , Pennisetum/growth & development , Pennisetum/microbiology , Endophytes/metabolism , Indoleacetic Acids/metabolism , Phosphates/analysis , Phosphates/metabolism , Bacillus/genetics , Siderophores/metabolism , Plant Roots/growth & development , Plant Roots/metabolism , Plant Roots/microbiology , Pennisetum/metabolism , Endophytes/genetics , Iron/metabolism
6.
Braz. j. microbiol ; 48(4): 656-670, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-889178

ABSTRACT

ABSTRACT This study aimed to explore the effects of two siderophore-producing bacterial strains on iron absorption and plant growth of peanut in calcareous soil. Two siderophore-producing bacterial strains, namely, YZ29 and DZ13, isolated from the rhizosphere soil of peanut, were identified as Paenibacillus illinoisensis and Bacillus sp., respectively. In potted experiments, YZ29 and DZ13 enhanced root activity, chlorophyll and active iron content in leaves, total nitrogen, phosphorus and potassium accumulation of plants and increased the quality of peanut kernels and plant biomass over control. In the field trial, the inoculated treatments performed better than the controls, and the pod yields of the three treatments inoculated with YZ29, DZ13, and YZ29 + DZ13 (1:1) increased by 37.05%, 13.80% and 13.57%, respectively, compared with the control. Based on terminal restriction fragment length polymorphism analysis, YZ29 and DZ13 improved the bacterial community richness and species diversity of soil surrounding the peanut roots. Therefore, YZ29 and DZ13 can be used as candidate bacterial strains to relieve chlorosis of peanut and promote peanut growth. The present study is the first to explore the effect of siderophores produced by P. illinoisensis on iron absorption.


Subject(s)
Arachis/growth & development , Arachis/microbiology , Bacillus/metabolism , Paenibacillus/metabolism , Iron/metabolism , Arachis/metabolism , Arachis/chemistry , Seeds/growth & development , Seeds/metabolism , Seeds/microbiology , Seeds/chemistry , Soil/chemistry , Soil Microbiology , Bacillus/isolation & purification , Bacillus/classification , Bacillus/genetics , Biological Transport , Siderophores/metabolism , Plant Roots/microbiology , Paenibacillus/isolation & purification , Paenibacillus/classification , Paenibacillus/genetics , Rhizosphere , Agricultural Inoculants/metabolism
7.
Braz. j. microbiol ; 48(3): 451-460, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-889134

ABSTRACT

Abstract This study was focused on the polyhydroxybutyrate (PHB) accumulation property of Bacillus aryabhattai isolated from environment. Twenty-four polyhydroxyalkanoate (PHA) producers were screened out from sixty-two environmental bacterial isolates based on Sudan Black B colony staining. Based on their PHA accumulation property, six promising isolates were further screened out. The most productive isolate PHB10 was identified as B. aryabhattai PHB10. The polymer production maxima were 3.264 g/L, 2.181 g/L, 1.47 g/L, 1.742 g/L and 1.786 g/L in glucose, fructose, maltose, starch and glycerol respectively. The bacterial culture reached its stationary and declining phases at 18 h and 21 h respectively and indicated growth-associated PHB production. Nuclear Magnetic Resonance (NMR) spectra confirmed the material as PHB. The material has thermal stability between 30 and 140 °C, melting point at 170 °C and maximum thermal degradation at 287 °C. The molecular weight and poly dispersion index of the polymer were found as 199.7 kDa and 2.67 respectively. The bacterium B. aryabhattai accumulating PHB up to 75% of cell dry mass utilizing various carbon sources is a potential candidate for large scale production of bacterial polyhydroxybutyrate.


Subject(s)
Bacillus/metabolism , Polyhydroxyalkanoates/biosynthesis , Starch/metabolism , Bacillus/isolation & purification , Bacillus/growth & development , Bacillus/genetics , Culture Media/metabolism , Culture Media/chemistry , Environmental Microbiology , Polyhydroxyalkanoates/chemistry , Glycerol/metabolism
8.
Braz. j. microbiol ; 47(4): 931-940, Oct.-Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-828205

ABSTRACT

Abstract Twelve bacterial strains isolated from shrimp farming ponds were screened for their growth activity on chitin as the sole carbon source. The highly chitinolytic bacterial strain was detected by qualitative cup plate assay and tentatively identified to be Cohnella sp. A01 based on 16S rDNA sequencing and by matching the key morphological, physiological, and biochemical characteristics. The cultivation of Cohnella sp. A01 in the suitable liquid medium resulted in the production of high levels of enzyme. The colloidal chitin, peptone, and K2HPO4 represented the best carbon, nitrogen, and phosphorus sources, respectively. Enzyme production by Cohnella sp. A01 was optimized by the Taguchi method. Our results demonstrated that inoculation amount and temperature of incubation were the most significant factors influencing chitinase production. From the tested values, the best pH/temperature was obtained at pH 5 and 70 °C, with Km and V max values of chitinase to be 5.6 mg/mL and 0.87 µmol/min, respectively. Ag+, Co2+, iodoacetamide, and iodoacetic acid inhibited the enzyme activity, whereas Mn2+, Cu2+, Tweens (20 and 80), Triton X-100, and EDTA increased the same. In addition, the study of the morphological alteration of chitin treated by enzyme by SEM revealed cracks and pores on the chitin surface, indicating a potential application of this enzyme in several industries.


Subject(s)
Bacillus/metabolism , Chitinases/metabolism , Phosphorus/metabolism , Temperature , Bacillus/isolation & purification , Bacillus/genetics , Bacillus/ultrastructure , Enzyme Stability/drug effects , Carbon/metabolism , RNA, Ribosomal, 16S/genetics , Kinetics , Chitinases/chemistry , Sequence Analysis, DNA , Enzyme Activation , Hydrogen-Ion Concentration , Ions , Metals , Nitrogen/metabolism
9.
Braz. j. microbiol ; 47(1): 120-128, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775124

ABSTRACT

Abstract Cyclodextrin glycosyltransferase (CGTase) catalyzes the conversion of starch into non-reducing cyclic sugars, cyclodextrins, which have several industrial applications. This study aimed to establish optimal culture conditions for β-CGTase production by Bacillus sp. SM-02, isolated from soil of cassava industries waste water lake. The optimization was performed by Central Composite Design (CCD) 2, using cassava flour and corn steep liquor as substrates. The maximum production of 1087.9 U mL−1 was obtained with 25.0 g L−1 of cassava flour and 3.5 g L−1 of corn steep after 72 h by submerged fermentation. The enzyme showed optimum activity at pH 5.0 and temperature 55 °C, and maintained thermal stability at 55 °C for 3 h. The enzymatic activity was stimulated in the presence of Mg+2, Ca+2, EDTA, K+, Ba+2 and Na+ and inhibited in the presence of Hg+2, Cu+2, Fe+2 and Zn+2. The results showed that Bacillus sp. SM-02 have good potential for β-CGTase production.


Subject(s)
Bacillus/isolation & purification , Bacillus/metabolism , Culture Media/chemistry , Glucosyltransferases/metabolism , Enzyme Activators/metabolism , Enzyme Inhibitors/analysis , Hydrogen-Ion Concentration , Manihot/metabolism , Soil Microbiology , Temperature , Zea mays/metabolism
10.
Braz. j. microbiol ; 47(1): 1-9, Jan.-Mar. 2016. tab, graf
Article in English | LILACS | ID: lil-775132

ABSTRACT

Abstract This study was conducted to isolate an acid-producing, alkaliphilic bacterium to reduce the alkalinity of cement industry waste (cement kiln dust). Gram-positive isolate KG1 grew well at pH values of 6–12, temperatures of 28–50 °C, and NaCl concentrations of 0–16% and thus was further screened for its potential to reduce the pH of an alkaline medium. Phenotypic characteristics of the KG1 isolate were consistent with those of the genus Bacillus, and the highest level of 16S rRNA gene sequence similarity was found with Bacillus halodurans strain DSM 497 (94.7%). On the basis of its phenotypic characteristics and genotypic distinctiveness from other phylogenetic neighbors belonging to alkaliphilic Bacillus species, the isolated strain was designated B. halodurans strain KG1, with GenBank accession number JQ307184 (= NCIM 5439). Isolate KG1 reduced the alkalinity (by 83.64%) and the chloride content (by 86.96%) of cement kiln dust and showed a potential to be used in the cement industry for a variety of applications.


Subject(s)
Bacillus/growth & development , Bacillus/metabolism , Biotechnology/methods , Industrial Waste , Waste Management/methods , Bacterial Typing Techniques , Bacillus/classification , Bacillus/isolation & purification , Cluster Analysis , Construction Materials , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , Temperature
11.
Electron. j. biotechnol ; 19(1): 23-28, Jan. 2016. ilus
Article in English | LILACS | ID: lil-781166

ABSTRACT

Background: Lignocellulosic biomass is a renewable, abundant, and inexpensive resource for biorefining process to produce biofuel and valuable chemicals. To make the process become feasible, it requires the use of both efficient pretreatment and hydrolysis enzymes to generate fermentable sugars. Ionic liquid (IL) pretreatment has been demonstrated to be a promising method to enhance the saccharification of biomass by cellulase enzyme; however, the remaining IL in the hydrolysis buffer strongly inhibits the function of cellulase. This study aimed to isolate a potential IL-tolerant cellulase producing bacterium to be applied in biorefining process. Result: One Bacillus sp., MSL2 strain, obtained from rice paddy field soil was isolated based on screening of cellulase assay. Its cellulase enzyme was purified and fractionated using a size exclusion chromatography. The molecular weight of purified cellulose was 48 kDa as revealed by SDS-PAGE and zymogram analysis. In the presence of the IL, 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) concentration of 1 M, the cellulase activity retained 77.7% of non-IL condition. In addition, the optimum temperature and pH of the enzyme is 50°C and pH 6.0, respectively. However, this cellulase retained its activity more than 90% at 55°C, and pH 4.0. Kinetic analysis of purified enzyme showed that the Km and Vmax were 0.8 mg/mL and 1000 μM/min, respectively. Conclusion: The characterization of cellulase produced from MSL2 strain was described here. These properties of cellulase made this bacterial strain become potential to be used in the biorefining process.


Subject(s)
Bacillus/enzymology , Cellulase/isolation & purification , Cellulase/biosynthesis , Oryza , Soil Microbiology , Temperature , Bacillus/metabolism , Biomass , Ionic Liquids , Biofuels , Hydrogen-Ion Concentration , Hydrolysis , Lignin
12.
Braz. j. microbiol ; 46(4): 1065-1076, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769637

ABSTRACT

Abstract Thermophilic 32 isolates and 20 reference bacilli were subjected to Rep-PCR and ITS-PCR fingerprinting for determination of their genotypic diversity, before screening lipase activities. By these methods, all the isolates and references could easily be differentiated up to subspecies level from each other. In screening assay, 11 isolates and 7 references were found to be lipase producing. Their extracellular lipase activities were measured quantitatively by incubating in both tributyrin and olive oil broths at 60 °C and pH 7.0. During the 24, 48 and 72-h period of incubation, the changes in the lipase activities, culture absorbance, wet weight of biomass and pH were all measured. The activity was determined by using pNPB in 50 mM phosphate buffer at pH 7.0 at 60 °C. The lipase production of the isolates in olive oil broths varied between 0.008 and 0.052, whereas these values were found to be 0.002-0.019 (U/mL) in the case of tyributyrin. For comparison, an index was established by dividing the lipase activities to cell biomass (U/mg). The maximum thermostable lipase production was achieved by the isolates F84a, F84b, and G. thermodenitrificans DSM 465T (0.009, 0.008 and 0.008 U/mg) within olive oil broth, whereas G. stearothermophilus A113 displayed the highest lipase activity than its type strain in tyributyrin. Therefore, as some of these isolates displayed higher activities in comparison to references, new lipase producing bacilli were determined by presenting their genotypic diversity with DNA fingerprinting techniques.


Subject(s)
Bacillus/chemistry , Bacillus/classification , Bacillus/enzymology , Bacillus/genetics , Bacillus/growth & development , Bacillus/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/classification , Bacterial Proteins/enzymology , Bacterial Proteins/genetics , Bacterial Proteins/growth & development , Bacterial Proteins/metabolism , Enzyme Stability/chemistry , Enzyme Stability/classification , Enzyme Stability/enzymology , Enzyme Stability/genetics , Enzyme Stability/growth & development , Enzyme Stability/metabolism , Genetic Variation/chemistry , Genetic Variation/classification , Genetic Variation/enzymology , Genetic Variation/genetics , Genetic Variation/growth & development , Genetic Variation/metabolism , Genotype/chemistry , Genotype/classification , Genotype/enzymology , Genotype/genetics , Genotype/growth & development , Genotype/metabolism , Hot Temperature/chemistry , Hot Temperature/classification , Hot Temperature/enzymology , Hot Temperature/genetics , Hot Temperature/growth & development , Hot Temperature/metabolism , Hydrogen-Ion Concentration/chemistry , Hydrogen-Ion Concentration/classification , Hydrogen-Ion Concentration/enzymology , Hydrogen-Ion Concentration/genetics , Hydrogen-Ion Concentration/growth & development , Hydrogen-Ion Concentration/metabolism , Lipase/chemistry , Lipase/classification , Lipase/enzymology , Lipase/genetics , Lipase/growth & development , Lipase/metabolism , Phylogeny/chemistry , Phylogeny/classification , Phylogeny/enzymology , Phylogeny/genetics , Phylogeny/growth & development , Phylogeny/metabolism
13.
Braz. j. microbiol ; 46(4): 1183-1191, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769666

ABSTRACT

Abstract Adhirasam is a cereal based, doughnut shaped, deep fried dessert consumed in the southern regions of India. The dough used to prepare adhirasam is fermented and contains rice flour and jaggery. The aim of the present study was to characterize the cultivable bacteria associated with this fermented dough and to identify a suitable starter culture for the production of quality adhirasam. In total, one hundred and seventy bacterial isolates were recovered from de Man Rogosa Sharp (MRS) agar, nutrient agar, lysogeny agar and tryptic soy agar media. Out of the 170 bacterial isolates, sixteen isolates were selected based on their ability to tolerate glucose and sucrose. All the bacterial isolates tolerated 15% glucose and 30% sucrose. Analyses of 16S rDNA gene sequences of the bacterial isolates showed that the dominant cultivable bacteria were members of the genus Bacillus. These strains were further used as starters and tested for their ability to ferment rice flour with jaggery to produce adhirasam dough. Organoleptic evaluation was carried out to choose the best starter strain. Adhirasam prepared from Bacillus subtilis isolates S4-P11, S2-G2-A1 and S1-G15, Bacillus tequilensis isolates S2-H16, S3-P9, S3-G10 and Bacillus siamensis isolate S2-G13 were highly acceptable to consumers. Adhirasam prepared using these starter cultures had superior product characteristics such as softness in texture, flavor and enhanced aroma and sweet taste.


Subject(s)
Humans , Bacillus/growth & development , Bacillus/metabolism , Food Microbiology , Bacterial Typing Techniques , Bacillus/classification , Bacillus/isolation & purification , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , India , Oryza/metabolism , /genetics , Sequence Analysis, DNA
14.
Braz. j. microbiol ; 46(4): 977-989, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769669

ABSTRACT

Abstract A total of 48 endophytic bacteria were isolated from surface-sterilized tissues of the medicinal plant Lonicera japonica, which is grown in eastern China; six strains were selected for further study based on their potential ability to promote plant growth in vitro (siderophore and indoleacetic acid production). The bacteria were characterized by phylogenetically analyzing their 16S rRNA gene similarity, by examining their effect on the mycelial development of pathogenic fungi, by testing their potential plant growth-promoting characteristics, and by measuring wheat growth parameters after inoculation. Results showed that the number of endophytic bacteria in L. japonica varied among different tissues, but it remained relatively stable in the same tissues from four different plantation locations. Among the three endophytic strains, strains 122 and 124 both had high siderophore production, with the latter showing the highest phosphate solubilization activity (45.6 mg/L) and aminocyclopropane-1-carboxylic acid deaminase activity (47.3 nmol/mg/h). Strain 170 had the highest indoleacetic acid (IAA) production (49.2 mg/L) and cellulase and pectinase activities. After inoculation, most of the six selected isolates showed a strong capacity to promote wheat growth. Compared with the controls, the increase in the shoot length, root length, fresh weight, dry weight, and chlorophyll content was most remarkable in wheat seedlings inoculated with strain 130. The positive correlation between enzyme (cellulose and pectinase) activity and inhibition rate on Fusarium oxysporum, the IAA production, and the root length of wheat seedlings inoculated with each tested endophytic strain was significant in regression analysis. Deformity of pathogenic fungal mycelia was observed under a microscope after the interaction with the endophytic isolates. Such deformity may be directly related to the production of hydrolytic bacterial enzymes (cellulose and pectinase). The six endophytic bacterial strains were identified to be Paenibacillus and Bacillus strains based on the results of 16S rRNA gene sequencing analysis and their physiological and biochemical characteristics. Results indicate the promising application of endophytic bacteria to the biological control of pathogenic fungi and the improvement of wheat crop growth.


Subject(s)
Bacillus/classification , Bacillus/genetics , Bacillus/growth & development , Bacillus/isolation & purification , Bacillus/metabolism , Bacillus/microbiology , China/classification , China/genetics , China/growth & development , China/isolation & purification , China/metabolism , China/microbiology , Endophytes/classification , Endophytes/genetics , Endophytes/growth & development , Endophytes/isolation & purification , Endophytes/metabolism , Endophytes/microbiology , Indoleacetic Acids/classification , Indoleacetic Acids/genetics , Indoleacetic Acids/growth & development , Indoleacetic Acids/isolation & purification , Indoleacetic Acids/metabolism , Indoleacetic Acids/microbiology , Lonicera/classification , Lonicera/genetics , Lonicera/growth & development , Lonicera/isolation & purification , Lonicera/metabolism , Lonicera/microbiology , Molecular Sequence Data/classification , Molecular Sequence Data/genetics , Molecular Sequence Data/growth & development , Molecular Sequence Data/isolation & purification , Molecular Sequence Data/metabolism , Molecular Sequence Data/microbiology , Paenibacillus/classification , Paenibacillus/genetics , Paenibacillus/growth & development , Paenibacillus/isolation & purification , Paenibacillus/metabolism , Paenibacillus/microbiology , Phylogeny/classification , Phylogeny/genetics , Phylogeny/growth & development , Phylogeny/isolation & purification , Phylogeny/metabolism , Phylogeny/microbiology , Plant Roots/classification , Plant Roots/genetics , Plant Roots/growth & development , Plant Roots/isolation & purification , Plant Roots/metabolism , Plant Roots/microbiology , Siderophores/classification , Siderophores/genetics , Siderophores/growth & development , Siderophores/isolation & purification , Siderophores/metabolism , Siderophores/microbiology , Triticum/classification , Triticum/genetics , Triticum/growth & development , Triticum/isolation & purification , Triticum/metabolism , Triticum/microbiology
15.
Braz. j. microbiol ; 46(3): 659-666, July-Sept. 2015. ilus
Article in English | LILACS | ID: lil-755822

ABSTRACT

Ten bacterial strains that utilize cyanide (CN) as a nitrogen source were isolated from cassava factory wastewater after enrichment in a liquid media containing sodium cyanide (1 mM) and glucose (0.2% w/v). The strains could tolerate and grow in cyanide concentrations of up to 5 mM. Increased cyanide levels in the media caused an extension of lag phase in the bacterial growth indicating that they need some period of acclimatisation. The rate of cyanide removal by the strains depends on the initial cyanide and glucose concentrations. When initial cyanide and glucose concentrations were increased up to 5 mM, cyanide removal rate increased up to 63 and 61 per cent by Bacillus pumilus and Pseudomonas putida. Metabolic products such as ammonia and formate were detected in culture supernatants, suggesting a direct hydrolytic pathway without an intermediate formamide. The study clearly demonstrates the potential of aerobic treatment with cyanide degrading bacteria for cyanide removal in cassava factory wastewaters.

.


Subject(s)
Biodegradation, Environmental , Bacillus/metabolism , Cyanides/metabolism , Pseudomonas putida/metabolism , Waste Water/chemistry , Ammonia/metabolism , Bacillus/isolation & purification , Bioreactors/microbiology , Formates/metabolism , Glucose/metabolism , India , Manihot , Pseudomonas putida/isolation & purification , /genetics
16.
Braz. j. microbiol ; 46(2): 347-354, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749729

ABSTRACT

Halophilic microorganisms are able to grow in the presence of salt and are also excellent source of enzymes and biotechnological products, such as exopolysaccharides (EPSs) and polyhydroxyalkanoates (PHAs). Salt-tolerant bacteria were screened in the Organic Composting Production Unit (OCPU) of São Paulo Zoological Park Foundation, which processes 4 ton/day of organic residues including plant matter from the Atlantic Rain Forest, animal manure and carcasses and mud from water treatment. Among the screened microorganisms, eight halotolerant bacteria grew at NaCl concentrations up to 4 M. These cultures were classified based on phylogenetic characteristics and comparative partial 16S rRNA gene sequence analysis as belonging to the genera Staphylococcus, Bacillus and Brevibacterium. The results of this study describe the ability of these halotolerant bacteria to produce some classes of hydrolases, namely, lipases, proteases, amylases and cellulases, and biopolymers. The strain characterized as of Brevibacterium avium presented cellulase and amylase activities up to 4 M NaCl and also produced EPSs and PHAs. These results indicate the biotechnological potential of certain microorganisms recovered from the composting process, including halotolerant species, which have the ability to produce enzymes and biopolymers, offering new perspectives for environmental and industrial applications.


Subject(s)
Bacillus/isolation & purification , Biological Products/analysis , Brevibacterium/isolation & purification , Hydrolases/analysis , Soil Microbiology , Sodium Chloride/metabolism , Staphylococcus/isolation & purification , Brazil , Bacillus/classification , Bacillus/genetics , Bacillus/metabolism , Brevibacterium/classification , Brevibacterium/genetics , Brevibacterium/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Soil , Staphylococcus/classification , Staphylococcus/genetics , Staphylococcus/metabolism
17.
Braz. j. microbiol ; 46(2): 455-464, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749744

ABSTRACT

Biomineralization is a known natural phenomenon associated with a wide range of bacterial species. Bacterial-induced calcium carbonate precipitation by marine isolates was investigated in this study. Three genera of ureolytic bacteria, Sporosarcina sp., Bacillus sp. and Brevundimonas sp. were observed to precipitate calcium carbonate minerals. Of these species, Sporosarcina sp. dominated the cultured isolates. B. lentus CP28 generated higher urease activity and facilitated more efficient precipitation of calcium carbonate at 3.24 ± 0.25 × 10−4 mg/cell. X-ray diffraction indicated that the dominant calcium carbonate phase was calcite. Scanning electron microscopy showed that morphologies of the minerals were dominated by cubic, rhombic and polygonal plate-like crystals. The dynamic process of microbial calcium carbonate precipitation revealed that B. lentus CP28 precipitated calcite crystals through the enzymatic hydrolysis of urea, and that when ammonium ion concentrations reached 746 mM and the pH reached 9.6, that favored calcite precipitation at a higher level of 96 mg/L. The results of this research provide evidence that a variety of marine bacteria can induce calcium carbonate precipitation, and may influence the marine carbonate cycle in natural environments.


Subject(s)
Bacillus/isolation & purification , Calcium Carbonate/metabolism , Caulobacteraceae/isolation & purification , Geologic Sediments/microbiology , Sporosarcina/isolation & purification , Ammonium Compounds/metabolism , Bacillus/classification , Bacillus/genetics , Bacillus/metabolism , Cluster Analysis , Caulobacteraceae/classification , Caulobacteraceae/genetics , Caulobacteraceae/metabolism , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Molecular Sequence Data , Phylogeny , /genetics , Sequence Analysis, DNA , Sporosarcina/classification , Sporosarcina/genetics , Sporosarcina/metabolism , Urea/metabolism , X-Ray Diffraction
18.
Electron. j. biotechnol ; 18(3): 244-251, May 2015. graf, tab
Article in English | LILACS | ID: lil-750654

ABSTRACT

Background Integrated statistical experimental designs were applied to optimize the medium constituents for the production of a dimethyl phthalate (DMP)-degrading strain Bacillus sp. QD14 in shake-flask cultures. A Plackett-Burman design (PBD) was applied to screen for significant factors, followed by the Steepest Ascent Method (SAM) to find the nearest region of maximum response. A Box-Behnken design (BBD) of the Response Surface Methodology (RSM) was conducted to optimize the final levels of the medium components. Results After the regression equation and response surface contour plots were analyzed, the concentrations of glucose, corn meal and NaCl were found to significantly influence the biomass of DMP-degrading bacteria. A combination of 22.88 g/L of glucose, 11.74 g/L of corn meal, and 10.34 g/L of NaCl was optimum for maximum biomass production of Bacillus sp. QD14. A 57.11% enhancement of the biomass production was gained after optimization in shake-flask cultivation. The biomass production of Bacillus sp. QD14 reached 9.13 ± 0.29 × 10(8) CFU/mL, which was an excellent match for the predicted value, and the mean value of the match degree was as high as 99.30%. Conclusion In this work, the key factors affected by the fermentation of DMP-degrading strain Bacillus sp. QD14 were optimized by PBD, SAM and BBD (RSM); the yield was increased by 57,11% in the conditions in our study. We propose that the conditions optimized in the study can be applied to the fermentation for commercialization production.


Subject(s)
Phthalic Acids/metabolism , Bacillus/metabolism , Biodegradation, Environmental , Fermentation
19.
Braz. j. microbiol ; 45(3): 903-910, July-Sept. 2014. ilus, graf
Article in English | LILACS | ID: lil-727019

ABSTRACT

A soil screened Bacillus flexus XJU-1 was induced to simultaneously produce alkaline amylase, alkaline lipase and alkaline protease at their optimum levels on a common medium under submerged fermentation. The basal cultivation medium consisted of 0.5% casein, 0.5% starch and 0.5% cottonseedoil as an inducer forprotease, amylase, and lipase, respectively. The casein also served as nitrogen source for all 3 enzymes. The starch was also found to act as carbon source additive for both lipase and protease. Maximum enzyme production occurred on fermentation medium with 1.5% casein, 1.5% soluble starch, 2% cottonseed oil, 2% inoculum size, initial pH of 11.0, incubation temperature of 37 °C and 1% soybean meal as a nitrogen source supplement. The analysis of time course study showed that 24 h was optimum incubation time for amylase whereas 48 h was the best time for both lipase and protease. After optimization, a 3.36-, 18.64-, and 27.33-fold increase in protease, amylase and lipase, respectively was recorded. The lipase was produced in higher amounts (37.72 U/mL) than amylase and protease about 1.27 and 5.85 times, respectively. As the 3 enzymes are used in detergent formulations, the bacterium can be commercially exploited to secrete the alkaline enzymes for use in detergent industry. This is the first report for concomitant production of 3 alkaline enzymes by a bacterium.


Subject(s)
Amylases/metabolism , Bacillus/enzymology , Bacillus/metabolism , Bacterial Proteins/metabolism , Detergents/metabolism , Endopeptidases/metabolism , Enzyme Inhibitors/metabolism , Lipase/metabolism , Bacillus/growth & development , Bacillus/isolation & purification , Carbon/metabolism , Culture Media/chemistry , Fermentation , Hydrogen-Ion Concentration , Nitrogen/metabolism , Soil Microbiology , Temperature , Time Factors
20.
Braz. j. microbiol ; 45(3): 1089-1094, July-Sept. 2014. ilus, tab
Article in English | LILACS | ID: lil-727042

ABSTRACT

P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 10(4.5) TCID50 to 10(2.75) TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.


Subject(s)
Animals , Animals, Domestic/virology , Antimicrobial Cationic Peptides/pharmacology , Antiviral Agents/pharmacology , Bacillus/metabolism , Viruses/drug effects , Antimicrobial Cationic Peptides/isolation & purification , Antiviral Agents/isolation & purification , Brazil , Bacillus/isolation & purification , Bacterial Proteins/isolation & purification , Bacterial Proteins/pharmacology , Fishes/microbiology , Gastrointestinal Tract/microbiology , Microbial Viability/drug effects , Temperature , Time Factors , Viral Load , Virus Replication/drug effects
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