Development of Paper Biosensor for the Detection of Phenol from Industrial Effluents Using Bioconjugate of Tyr-AuNps Mediated by Novel Isolate Streptomyces tuirus

Paper biosensor was developed using Tyr-AuNps bioconjugate produced by Streptomyces for the detection of phenol from the effluent of wine, paper, and plastic industries. Among three filter papers assessed, Whatman number 2 filter paper was proved to be the best paper base for the development of biosensor. Tyrosinase and gold nanoparticles being produced by a single novel isolate Streptomyces tuirus DBZ39 proved to be efficient bioconjugate for the detection of phenol constituents, due to its biocompatibility. The substrate specific catalytic activity of the tyrosinase and unique Surface Plasmon Resonance attribute of gold nanoparticles are the cause for efficient detection of phenol constituents from the effluent of wine, paper, and plastic industries in 3 min. The different types and quantity of phenolic constituents in various industrial effluents, such as phenol in wine, dopamine in paper, and catechol in plastic effluents, were accurately detected by the bioconjugate. The efficacy of tyrosinase in the detection of phenol constituents was expected to be enhanced by the gold nanoparticles because of their electron, optical, and magnetic properties. This novel paper strip biosensor could be cost-effective and efficient means of future devices for the detection of phenolic pollutants from any environmental samples

Novel application of Nerium leaf and Image J software in drop collapse assay for rapid screening of biosurfactant producing microorganisms

484-492Biosurfactants are attractive molecules with varied applicationsmainly oil degradation, emulsification, bioremediation, therapeutics and conjugation of nanoparticles. The existing screening methods for biosurfactants are inappropriate and too tedious. Here, we have explored a novel approach with drop collapse assay wherein we replaced the microtiter well plate with the naturally hydrophobic Nerium (Nerium oleander L.) leaf. The stability of beaded drops on the leaf indicates negative phenomenon, and spreading of drop indicates positive phenomenon for surfactant property, as confirmed by the measuring drop diameter using Image J software. Fifty five bacterial cultures isolated from oil contaminated site were screened through this novel approach which revealed that the isolates DNM49 (6.75±0.29 mm), DNM50 (7.45±0.19 mm) and DNM51 (6.14±0.82 mm) were the best in terms of surface tension reduction, although thirty other isolates were also found to be positive. A gradation of activity in terms of surface tension reduction was also established based on drop diameter. The results demonstrated promising application of Nerium leaf with Image J software in drop collapse assay as an eco-friendly and cost-effective and technically authenticated alternative to the existing assays

Novel application of Nerium leaf and Image J software in drop collapse assay for rapid screening of biosurfactant producing microorganisms

Biosurfactants are attractive molecules with varied applicationsmainly oil degradation, emulsification, bioremediation, therapeutics and conjugation of nanoparticles. The existing screening methods for biosurfactants are inappropriate and too tedious. Here, we have explored a novel approach with drop collapse assay wherein we replaced the microtiter well plate with the naturally hydrophobic Nerium (Nerium oleander L.) leaf. The stability of beaded drops on the leaf indicates negative phenomenon, and spreading of drop indicates positive phenomenon for surfactant property, as confirmed by the measuring drop diameter using Image J software. Fifty five bacterial cultures isolated from oil contaminated site were screened through this novel approach which revealed that the isolates DNM49 (6.75±0.29 mm), DNM50 (7.45±0.19 mm) and DNM51 (6.14±0.82 mm) were the best in terms of surface tension reduction, although thirty other isolates were also found to be positive. A gradation of activity in terms of surface tension reduction was also established based on drop diameter. The results demonstrated promising application of Nerium leaf with Image J software in drop collapse assay as an eco-friendly and cost-effective and technically authenticated alternative to the existing assays

Purification and characterization of tyrosinase from Streptomyces vinceudrauppus DSV 5

145-153Streptomyces vinceudrauppus DSV 5 is the first investigated report for tyrosinase activity. The studies presented in this research show that this organism may be a future source for larger production of tyrosinase. The enzyme was purified initially with 140 ml of culture filtrate. The crude enzyme was primarily purified by centrifugation, followed by ammonium sulfate precipitation and ultrafiltration and employed to ion exchange chromatography. Thereafter, the enzyme was loaded on a Sephadex G-75 column and, after ultra filtration, 0.54 mg of purified tyrosinase were obtained and confirmed results from sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Tyrosinase kinetics was determined with L-DOPA as substrate, the kinetic parameters are Km - 0.17 mM and Vmax - 227 IU/ml were determined

The Occurrence of potential and novel isolates of Oceanobacillus sp. JAS12 and Salinicoccus sp. JS20 recovered from West Coast of Arabian Sea, India

Many halophiles were considered to be extremophiles due to their inborn industrial potentials and tolerance to hostile environmental conditions. The isolated halophilic bacteria described in the present study are not only grown at environmentally adverse conditions, also they can be able to produce bioactive molecules. Among the isolated strains, Oceanobacillus iheyensis strain JAS12 and Salinicoccus roseus strain JS20 are known for the unique biotechnological applications. The isolate Oceanobacillus sp. grows well at 35-55 degrees C (optimum 45 degrees C) and pH 6 to 12 (maximum growth at pH 8), interestingly the strain could hydrolyze casein, starch and gelatin. The G+C content was 40.2 mol % and the major fatty acids are iso-15:0: 30.52%, primary-C15: 0 (29.29 %), iso-14:0 (16.15%) anteiso-C17: 0 (4.03%). Another isolate was Salinicoccus sp. JS20 The DNA G+C content was 50.4 mol % and the major fatty acids are anteiso-C15: 0 (26.23%), iso15:0, (17.62%)Y, 16:0 (11.5%), anteiso-C17: 0 (7.7 %), iso- C16: 0 (10.20 %), iso-17:0: (5.43%) and iso-C14: 0 (3.97 %). These isolates are also producers of many extracellular enzymes such as protease, amylase, inulinases, gelatinase and beta-fructofurinosidase above the optimal conditions. Oceanobacillus sp. JAS12 16S rRNA gene sequence similarity is 99% similar to the reported genera. Salinicoccus sp. JS20 indicated 96% 16S rRNA sequence similarity with near species Salinicoccus genus, thus, they were found to be novel concerning to their genetic makeup and biochemical features.Peer reviewe

Production and Cytotoxicity of Extracellular Insoluble and Droplets of Soluble Melanin by Streptomyces lusitanus DMZ-3

A Streptomyces lusitanus DMZ-3 strain with potential to synthesize both insoluble and soluble melanins was detected. Melanins are quite distinguished based on their solubility for varied biotechnological applications. The present investigation reveals the enhanced production of insoluble and soluble melanins in tyrosine medium by a single culture. Streptomyces lusitanus DMZ-3 was characterized by 16S rRNA gene analysis. An enhanced production of 5.29 g/L insoluble melanin was achieved in a submerged bioprocess following response surface methodology. Combined interactive effect of temperature (50°C), pH (8.5), tyrosine (2.0 g/L), and beef extract (0.5 g/L) were found to be critical variables for enhanced production in central composite design analysis. An optimized indigenous slant culture system was an innovative approach for the successful production (264 mg/L) of pure soluble melanin from the droplets formed on the surface of the culture. Both insoluble and soluble melanins were confirmed and characterized by Chemical, reactions, UV, FTIR, and TLC analysis. First time, cytotoxic study of melanin using brine shrimps was reported. Maximum cytotoxic activity of soluble melanin was Lc50-0.40 µg/mL and insoluble melanin was Lc50-0.80 µg/mL

<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Development of bioconjugate from <i style="mso-bidi-font-style:normal">Streptomyces </i><span style="mso-bidi-font-style:italic">tyrosinase and gold nanoparticles for rapid detection of phenol constituents</span></span>

1071-1081Most of the phenol compounds are toxic and have been considered as hazardous pollutants. Several physicochemical and biological methods are available to detect and monitor the phenol pollutants in water and soil. In the present study, phenol constituents of winery, paper and plastic industrial effluents were successfully detected employing tyrosinase-gold nanoparticles bioconjugate. The synthesis of extracellular tyrosinase and gold nanoparticles was achieved by a single isolate of Streptomyces sp. DBZ-39. Enhanced production (369.41 IU) of tyrosinase was produced in submerged bioprocess employing response surface method with central composite design. Extracellular gold nanoparticles synthesized (12-18 nm) by Streptomyces sp. DBZ-39 were characterized with TEM, EDAX and FTIR analysis. A rapid detection (within 10 min) of phenol constituents from winery effluents was achieved by bioconjugate, when compared to tyrosinases and gold nanoparticles independently. Streptomyces tyrosinase could exhibit relatively a better performance than commercially available mushroom tyrosinase in the detection of phenol constituents. Winery effluent has shown much higher content (0.98 O.D) of phenol constituents than paper and plastic effluents based on the intensity of color and U.V absorption spectra. </span

Characterization and Cytotoxicity of Pseudomonas Mediated Rhamnolipids Against Breast Cancer MDA-MB-231 Cell Line

A biosurfactant producing bacterium was identified as Pseudomonas aeruginosa DNM50 based on molecular characterization (NCBI accession no. MK351591). Structural characterization using MALDI-TOF revealed the presence of 12 different congeners of rhamnolipid such as Rha-C8-C8:1, Rha-C10-C8:1, Rha-C10-C10, Rha-C10-C12:1, Rha-C16:1, Rha-C16, Rha-C17:1, Rha-Rha-C10:1-C10:1, Rha-Rha-C10-C12, Rha-Rha-C10-C8, Rha-Rha-C10-C8:1, and Rha-Rha-C8-C8. The radical scavenging activity of rhamnolipid (DNM50RL) was determined by 2, 3-diphenyl-1-picrylhydrazyl (DPPH) assay which showed an IC50 value of 101.8 mu g/ ml. The cytotoxic activity was investigated against MDA-MB-231 breast cancer cell line by MTT (4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide) assay which showed a very low IC50 of 0.05 mu g/ ml at 72 h of treatment. Further, its activity was confirmed by resazurin and trypan blue assay with IC50 values of 0.01 mu g/ml and 0.64 mu g/ ml at 72 h of treatment, respectively. Thus, the DNM50RL would play a vital role in the treatment of breast cancer targeting inhibition of p38MAPK