scholarly journals Response surface methodology mediated optimization of Lignin peroxidase from Bacillus mycoides isolated from Simlipal Biosphere Reserve, Odisha, India

2022 ◽  
Vol 20 (1) ◽  
Author(s):  
Subhashree Rath ◽  
Manish Paul ◽  
Hemanta Kumar Behera ◽  
Hrudayanath Thatoi
Keyword(s):  
Methylene Blue ◽  
Response Surface Methodology ◽  
Bacterial Strain ◽  
Biosphere Reserve ◽  
Minimal Salt Medium ◽  
Lignin Biodegradation ◽  
Bioethanol Production ◽  
Salt Medium ◽  
Bacterial Strains ◽  
Bacillus Mycoides

Abstract Background Lignin is a complex polymer of phenyl propanoid units found in the vascular tissues of the plants as one of lignocellulose materials. Many bacteria secrete enzymes to lyse lignin, which can be essential to ease the production of bioethanol. Current research focused on the study of ligninolytic bacteria capable of producing lignin peroxidase (LiP) which can help in lignin biodegradation and bioethanol production. Ligninolytic bacterial strains were isolated and screened from the soil samples of Simlipal Biosphere Reserve (SBR), Odisha (India), for the determination of their LiP activity. Enzymatic assay and optimization for the LiP activity were performed with the most potent bacterial strain. The strain was identified by morphological, biochemical, and molecular methods. Results In this study, a total of 16 bacteria (Simlipal ligninolytic bacteria [SLB] 1–16) were isolated from forest soils of SBR using minimal salt medium containing lignin. Out of the 16 isolates, 9 isolates showed decolourization of methylene blue dye on LB agar plates. The bacterial isolates such as SLB8, SLB9, and SLB10 were able to decolourize lignin with 15.51%, 16.80%, and 33.02%, respectively. Further enzyme assay was performed using H2O2 as substrate and methylene blue as an indicator for these three bacterial strains in lignin containing minimal salt medium where the isolate SLB10 showed the highest LiP activity (31.711 U/mg). The most potent strain, SLB10, was optimized for enhanced LiP enzyme activity using response surface methodology. In the optimized condition of pH 10.5, temperature 30 °C, H2O2 concentration 0.115 mM, and time 42 h, SLB10 showed a maximum LiP activity of 55.947 U/mg with an increase of 1.76 times from un-optimized condition. Further chemical optimization was performed, and maximum LiP activity as well as significant dye-decolourization efficiency of SLB10 has been found in bacterial growth medium supplemented individually with cellulose, yeast extract, and MnSO4. Most notably, yeast extract and MnSO4-supplemented bacterial culture medium were shown to have even higher percentage of dye decolourization compared to normal basal medium. The bacterial strain SLB10 was identified as Bacillus mycoides according to morphological, biochemical, and molecular (16S rRNA sequencing) characterization and phylogenetic tree analysis. Conclusion Result from the present study revealed the potential of Bacillus mycoides bacterium isolated from the forest soil of SBR in producing LiP enzyme that can be evaluated further for application in lignin biodegradation and bioethanol production. Scaling up of LiP production from this potent bacterial strain could be useful in different industrial applications. Graphical Abstract

scholarly journals Evidence for Enhanced Dissipation of Chlorpyrifos in an Agricultural Soil Inoculated with Serratia Rubidaea Strain ABS 10

2021 ◽  
Author(s):  
Asma Ben Salem ◽  
Hanene Chaabane ◽  
Tesnime Ghazouani ◽  
Pierluigi Caboni ◽  
Valentina Coroneo ◽  
...  
Keyword(s):  
16S Rrna ◽  
Bacterial Strain ◽  
Agricultural Soil ◽  
Liquid Culture ◽  
Minimal Salt Medium ◽  
Salt Medium ◽  
Sterile Soil ◽  
Rrna Sequencing ◽  
Biochemical Analyses ◽  
Serratia Rubidaea

Abstract Important mineralization of 14C-chlorpyrifos was found in a Tunisian soil exposed repeatedly to this insecticide. A bacterial strain able to grow in minimal salt medium (MSM) supplemented with 25 mg L− 1 of chlorpyrifos was isolated from this soil. It was characterized as Serratia rubidaea strain ABS 10 using morphological and biochemical analyses, as well as 16S rRNA sequencing. In liquid culture S. rubidaea stain ABS 10 was able to almost entirely dissipate chlorpyrifos within 48 hours of incubation. Although, S. rubidaea strain ABS 10 was able to grow on MSM supplemented with chlorpyrifos and to dissipate it in liquid culture, it was not able to mineralize 14C-chlorpyrifos. Therefore, one can conclude that the dissipation capability of this bacteria might be attributed to its capacity to adsorb CHL. In both non-sterile and sterile soil inoculated with S. rubidaea strain ABS 10, chlorpyrifos was more rapidly dissipated than in respective controls.

scholarly journals Optimization of xylanase from Pseudomonas mohnii isolated from Simlipal Biosphere Reserve, Odisha, using response surface methodology

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Manish Paul ◽  
Dipti Pravamayee Nayak ◽  
Hrudayanath Thatoi
Keyword(s):  
Response Surface Methodology ◽  
Enzyme Activity ◽  
Response Surface ◽  
Incubation Time ◽  
Bacterial Strain ◽  
Biosphere Reserve ◽  
Nutrient Agar ◽  
Corn Cob ◽  
Xylanase Production ◽  
Rsm Optimization

Abstract Background Xylanase has long been recognized as a widely used industrially important enzyme. There are some bacterial species already reported to produce xylanase which have potent xylanolytic activity towards the use of this enzyme in the production of bioethanol from lignocellulosic biomass. In this view, an efficient xylanolytic bacterial strain was isolated and screened from the soil sample of Simlipal Biosphere Reserve. Enzymatic assay for the xylanase activity was evidenced from the most potent bacterial strain, and the culture condition was optimized for obtaining the maximum enzyme activity. The most potent xylanolytic strain was also identified using biochemical and molecular methods. Results Nineteen xylanolytic bacteria (SXB1-SXB19) were isolated from Simlipal forest soil samples following dilution plate technique using corn cob xylan-enriched nutrient agar medium and screened for their xylanase-producing ability. Among these isolates, SXB19 showed maximum xylanolytic potential with a halozone size of 2.5 cm as evident in the formation of prominent yellow patches surrounding its growth in xylan-enriched nutrient agar plate. In unoptimized condition, SXB19 showed the highest enzymatic activity of 22.5 IU/ml among the 19 bacterial strains. In order to optimize the culture conditions for maximizing the xylanase production, Box-Behnken design of response surface methodology (RSM) was used. Four variables such as incubation time, pH, substrate (corn cob xylan) concentration, and temperature were considered for the RSM optimization study. From the results, it is evident that in an optimized condition of incubation time 36 h, pH 6.0, xylan concentration 0.5%, and temperature 42.5 °C, the enzyme activity reached a maximum of 152 IU/ml with nearly 6.75 times increase from the unoptimised condition. Besides, xylanase production from SXB19 was considerable in the presence of xylan followed by starch, nitrogen source such as urea followed by yeast extract, and mineral ion sources such as KCl followed by MgSO4 and ZnSO4. From different biochemical tests, 16S rRNA gene sequencing, and phylogenetic analysis, the bacterial strain SXB19 was identified as Pseudomonas mohnii. Conclusion The isolation of Pseudomonas mohnii, a potent xylanolytic bacterium from Simlipal, is a new report which opens up an opportunity for industrial production of xylanase for bioethanol production and other applications. Graphical abstract

scholarly journals Effect of TiO2 on Selected Pathogenic and Opportunistic Intestinal Bacteria

2021 ◽  
Author(s):  
Ewa Baranowska-Wójcik ◽  
Dominik Szwajgier ◽  
Klaudia Gustaw
Keyword(s):  
Titanium Dioxide ◽  
Bacterial Strain ◽  
Intestinal Bacteria ◽  
Food Additive ◽  
Bacterial Strains ◽  
Gastrointestinal Microbiota ◽  
Food Grade ◽  
The Eu

AbstractFood-grade titanium dioxide (TiO2) containing a nanoparticle fraction (TiO2 NPs-nanoparticles) is widely used as a food additive (E171 in the EU). In recent years, questions concerning its effect on the gastrointestinal microbiota have been raised. In the present study, we examined interactions between bacteria and TiO2. The study involved six pathogenic/opportunistic bacterial strains and four different-sized TiO2 types: three types of food-grade E171 compounds and TiO2 NPs (21 nm). Each bacterial strain was exposed to four concentrations of TiO2 (60, 150, 300, and 600 mg/L TiO2). The differences in the growth of the analyzed strains, caused by the type and concentration of TiO2, were observed. The growth of a majority of the strains was shown to be inhibited after exposure to 300 and 600 mg/L of the food-grade E171 and TiO2 NPs.

Genetics of symbiosis and nitrogen fixation in legumes

1969 ◽  
Vol 172 (1029) ◽  
pp. 417-437 ◽  
Keyword(s):  
Nitrogen Fixation ◽  
Bacterial Strain ◽  
Host Plants ◽  
Strain Differences ◽  
Homogeneous Material ◽  
Developmental Sequence ◽  
Bacterial Strains ◽  
Nodule Bacteria ◽  
Microbial Genetics ◽  
Nodular Tissue

Soon after the isolation of nodule bacteria in 1888, differences were recognized in the ability of bacterial strains to form nodules on particular host plants and in the nitrogen-fixing ability of the nodules so formed. These and other symbiotic heterogeneities were attributed, sometimes correctly, to bacterial strain differences, not then thought to be open to formal genetic analysis. The realization that the host plant was an essential component of this variability came only gradually, stimulated by observations of host varietal differences and by the demand for reliable and homogeneous material for experimental work. Only within the last two decades has host variability been studied by plant breeding, and bacterial strain differences by some of the methods of microbial genetics. This review, except for a brief reference to earlier work of some historic interest, will consider only genetic problems open to investigation by these methods. The developmental sequence in all legume nodules is broadly similar. The initial infection phases are followed by the induction of the nodule, the invasion of part of the nodular tissue and culminate in bacteroid formation and nitrogen fixation; the genetics of symbiosis will be considered in this context.

scholarly journals Wild type Bacillus subtilis treated with ethyl methyl sulphonate produced catabolite insensitive mutants with improved cellulase production

2021 ◽  
Author(s):  
Oladipo Olaniyi
Keyword(s):  
Bacillus Subtilis ◽  
Carbon Source ◽  
Enzyme Production ◽  
Cellulase Activity ◽  
Cellulase Production ◽  
Minimal Salt Medium ◽  
Salt Medium ◽  
Production Medium ◽  
Wild Type ◽  
Ethyl Methyl

Abstract The goal of this present investigation was to mutagenize Bacillus subtilis with Ethyl Methyl Sulphonate (EMS), screen the mutants for cellulase production and evaluate the influence of different glucose concentrations on their cellulase production potentials. The wild type B. subtilis was treated with 20, 40, 60 and 80 µl of EMS and the mutants generated were screened for cellulase production in minimal salt medium containing carboxylmethylcellulose (CMC) as the carbon source. Quantitatively, cellulase activity and protein contents were determined by dinitrosalicylic acid and Lowry methods respectively. Seven mutants were developed from each of the EMS concentration bringing the total to twenty-eight from all the concentrations. Approximately 14 and 57% of the mutants developed from 40 and 60µl of EMS had higher cellulase activities than the wild type, while none of the mutants developed from 20 and 80 µl of EMS had better activities than the wild type. The supplementation of 0.2, 0.5, 1.0 and 1.5% glucose in enzyme production medium caused approximately 100, 14, 29 and 14% cellulase repression respectively in the mutants developed from 60µl EMS. Mutants MSSS02 and MSSS05 were considered as catabolite insensitive mutants because their cellulase production were enhanced in comparison to wild type.

scholarly journals Influence of cultivation conditions on IAA - producing activity of endophytic bacterial strains isolated from morning-glory (IPOMOEA PES-CAPRAE (L.) R.Br.)

2021 ◽  
Vol 36 ◽  
pp. 05003
Author(s):  
Nguyen Van Zhang ◽  
Nguyen Thi Thu ◽  
Vu Thi Linh ◽  
V.V. Pylnev ◽  
M.I. Popchenko
Keyword(s):  
Carbon Source ◽  
Culture Medium ◽  
Nitrogen Sources ◽  
Morning Glory ◽  
Bacterial Strains ◽  
Cultivation Conditions ◽  
Bacillus Mycoides ◽  
Carbon And Nitrogen Sources ◽  
Carbon And Nitrogen ◽  
Study Results

This work presents the experimental study results of the influence of the culture medium on the ability to IAA synthesis of three endophytic strains TH10R, TH11T, and TH13T from roots of Ipomoea pes-caprae. Three investigated strains give the highest IAA concentration after 96 h of cultivation. A significant increase in IAA biosynthesis was obtained by cultivating the TH10R strain in a medium containing lactose or starch as a carbon source and NH4Cl or KNO3 as a nitrogen source. The TH11T strain produces the maximum amount of IAA, using glucose or xylose and KNO3 or NH4NO3 as carbon and nitrogen sources, respectively. Sucrose is a suitable carbon source for the TH13T strain; on a sucrose-containing medium, the TH13T strain produces the highest IAA amount. The most active strain is TH10R, identified as Bacillus mycoides and named Bacillus mycoides TH10R.

Sign in / Sign up

Export Citation Format

Share Document