Fibrous protein composite scaffolds (3D) for tissue regeneration: An in vitro study on skeletal muscle regeneration.

The present study explores the differentiation of myoblasts in bioengineered 3D composite scaffolds containing keratin and gelatin. Based on the composition and rheological properties three different scaffolds namely HM1, HM2 and HM3 were prepared, characterized and employed for the present study. The scaffolds were then subjected to C2C12 myoblasts differentiation under in vitro conditions as per the standard protocols. Results reveal a wide variation in the elastic modulus, water uptake and degradation rate of the scaffolds significantly impact the myogenesis processes. Composite scaffolds HM2 and HM3 ease the myogenesis compared to HM1, wherein, results in nil myogenesis. Among HM2 and HM3, accelerated myogenesis and the significant expression of myogenin mRNA levels along with extensive myotube development were observed in the HM3 scaffold. In conclusion, scaffolds modulus play a vital role in myogenesis and the observations of the present study provide a possible strategy for better skeletal muscle regeneration using composite scaffolds.

Preparation, characterization and cell response studies on bioconjugated 3D protein hydrogels with wide-range stiffness: An approach on cell therapy and cell storage.

The present study emphasizes the preparation and characterization of bioconjugated keratin-gelatin (KG) 3D hydrogels with wide-range stiffness to study cell response for cell therapy and cell storage applications. In brief, human hair keratin and bovine gelatin at different ratios bioconjugated using EDC/NHS provide five hydrogels (KG-1, KG-2.5, KG -5, KG-7.5 and KG-9) with modulus ranging from 0.9 ±â€¯0.1 to 10.9 ±â€¯0.4 kPa. Based on swelling, stability, porosity, and degradation parameters KG-5 and KG-9 are employed to assess the human dermal fibroblast (HDF) cell response, cell delivery and cell storage respectively. Characterization studies revealed the concentration of keratin determines the modulus/stiffness of the hydrogels, whereas gelatin concentration plays a vital role in porosity, swelling percentage, and degradation properties. HDF cell behaviour in the chosen hydrogels assessed based on cell adhesion, cell proliferation, PCNA expression, MTT assay, and DNA quantification. We observed the best cell behaviour in KG-5 hydrogels than in the KG-9 matrix. In cell storage and cell delivery studies, the KG-9 matrix displayed promising results. Thus, the present study concludes bioconjugated keratin-gelatin 3D hydrogel with modulus below 3.0 kPa facilitates the proliferation of HDFs, whereas matrix above 10 kPa modulus supports cell storage and cell recovery. The observations of the present study suggest the suitability of bioconjugated fibrous protein 3D hydrogel for cell therapy and cell storage.

Elucidation of 2, 4-Dichlorophenol degradation by Bacillus licheniformis strain SL10.

2,4-Dichlorophenol (2,4-DCP) is a priority pollutant according to US Environmental Protection Agency. Its use in various chemical industries and its presence in the effluent necessitate effective removal studies. The present study focuses on degradation of 2,4-DCP by phenol adapted bacteria Bacillus licheniformis strain SL10 (MTCC 25059) at a relatively faster rate. The organism exhibited tolerance to 150 ppm of 2,4-DCP and showed a linear relationship between the growth and substrate concentration (µmax 0.022/h) and the inhibitory concentration was 55.74 mg/L. The degradation efficiency of the organism was 74% under optimum conditions but increased to 97% when the growth medium containing nil sodium chloride. The degradation of 2,4-DCP was effected by the action of extracellular cocktail enzyme containing Catechol 2, 3 dioxygenase (C23DO), phenol hydroxylase and Catechol, 1,2 dioxygenase (C12DO). In vitro enzymatic degradation studies exhibit 98% degradation of 50 ppm of 2,4-DCP within 2 h. Analyses of degradation products infer that the chosen organism followed a meta-cleavage pathway while degrading 2,4-DCP. In conclusion, the bacteria Bacillus licheniformis strain SL10 finds potential application in the remediation of 2,4-DCP.

Plant growth promotion and chilli anthracnose disease suppression ability of rhizosphere soil actinobacteria.

AIM: The aim of this study was to screen potential plant growth promoting rhizobacterial (PGPR) actinobacterial isolate with effective inhibition against anthracnose causing fungal pathogen Colletotrichum capsici. METHODS AND RESULTS: In this study, actinobacterias were isolated from rhizosphere soil using dilution plate method and tested for antagonistic potential against pathogenic fungi C. capsici. In primary and secondary screening tests, the actinobacterial isolate BS-26 displayed high antagonistic activity against the fungal pathogen. Isolate BS-26 was identified as Streptomyces violaceoruber based on 16S rDNA sequencing. Furthermore, indole acetic acid production, phosphate solubilization and ammonia production have been confirmed in the S. violaceoruber that suggest their potential to be used as PGPR bacteria. A green house experiment showed that application of S. violaceoruber fermentation broth reduced the incidence of the chilli anthracnose and promoted the growth of chilli seedlings with a significant increase in germination %, total plant height, fresh weight and chlorophyll content when compared to controls. CONCLUSION: Streptomyces violaceoruber can be applied as a biofertilizer and biocontrol agent for growing chillies against the attack of fungal pathogen C. capsici. SIGNIFICANCE OF IMPACT OF THE STUDY: The damage caused by anthracnose disease is an issue of concern, affecting negatively the economy involved in chilli cultivation. As chemical methods of control have serious disadvantages, biocontrol approach using beneficial (PGPR) micro-organisms shall be a better alternative to control crop diseases.

Efficacy of free and encapsulated Bacillus lichenformis strain SL10 on degradation of phenol: A comparative study of degradation kinetics.

The present study exemplifies phenol degradation efficacy of the free and encapsulated bacterial isolate, explored the degradation kinetics and storage stability in detail. In brief, isolation, identification and phenol degradation potential of the bacterial made from wastewater treated sludge samples. The organism identified as B. licheniformis demonstrates phenol degradation at a concentration more than 1500 ppm. Optimization of environmental parameters reduces the time taken for degradation considerably. The organism has further been encapsulated using whey protein and the efficacy of encapsulated species suggested that encapsulation protects the cells from high concentration of phenol and at the same time expedite the degradation of the chosen pollutant at appreciable level. The encapsulated species effectively degrade 3000 ppm concentration of phenol within 96 h of incubation. Both pH and temperature stability observed in the encapsulated species suggests the effectiveness of the encapsulation. The encapsulated cells displayed storage stability for a four week period at 4 C and reusability up to three exposures. Degradation effected through intracellular catechol 2,3 dioxygenase. In conclusion, encapsulation of B. licheniformis (i) protects the cells from direct exposure to toxic pollutants; (ii) facilitates the field scale application and (iii) eliminate the practical difficulties in handling wet biomass in field application and assures the best possible way of remediating the phenol contaminated soil.