Bacillus Cereus Bacterium: A Human Pathogen

Background & Objectives: Monotherapy and combination therapy studies were to determine antileishmanial activities of the methanolic and water leaf extracts from Aloe secundiflora and Plumbago capensis.

Methods: The plants were analyzed by determining the Minimum Inhibition Concentration (MIC), Nitric Oxide (NO) production stimulation, Infection Rates (IR) and Multiplication Index (MI). Cytotoxicity of these plant extracts was also assessed.

Results: The MIC levels of water and methanolic plant extracts, amphotericin B and Pentostam were 2000μg/ml, 1000μg/ml, 125μg/ml and 250μg/ml respectively against Leishmania major promastigotes. Study revealed that water and methanolic plant extracts significantly inhibited the growth of Leishmania parasites (P≤0.05) as compared to amphotericin B with respect to the parasite infection rates and MIC levels. The IC50 for the water and methanolic plant extracts was 279.488μg/ml and 42.824μg/ml respectively. A similar extraction procedure was done for P.capensis. When administered orally, a combination of P.capensis and A.secundiflora proved to be more effective than that of the methanolic extract with LDU units of 4,800 and 15,300 respectively. Water extracts of P.capensis when used alone gave LDU of 5,200 units, methanolic extract gave 11,000 units. Aloe secundiflora water and methanolic extracts gave the same LDU of 10,700. Methanolic extract combinations of the two plants were the least effective, yielding the highest LDU of 21,000 units.

Interpretation & Conclusion: The results suggest that a combination oral therapy of extracts of the two plants and monotherapy using P.capensis can be effective methods of partially treating leishmaniasis.

Melanoma occurs when the pigment-producing cells (melanocytes) that give colour to the skin become cancerous. Malignant melanoma has become one major problem for its higher rate of occurrence among patients than any other type of cancer throughout the world. Hence, it has become very crucial to treat melanoma skin cancers by early detection and prevention. It is remarkable how an advanced therapy like gene therapy is leading towards a better solution for melanoma skin cancer. Not only can gene therapy cure an individual, it also prevents same set of diseases throughout a blood line. With supported evidences from research and clinical trials, gene therapy also provides clue for a new generation treatment for different diseases including cancer.

Twelve quarters of six lactating cows were inoculated with Mycoplasma leachii strain GN407 through intramammary ductal infusion, and another twelve quarters were inoculated with Mycoplasma culture medium as controls. One lactating cow was used as negative control, in which two quarters were inoculated with Mycoplasma culture medium, and another two quarters were not inoculated with any medium. Clinical observations, histopathology and Immunohistochemistry (IHC) detection were performed on Post Inoculation Days (PIDs) 3, 6 and 9 to elucidate the pathogenicity of M. leachii in bovine mastitis. From PIDs 3 to 9, twelve inoculated quarters developed mild to severe clinical mastitis and mammary tissue histopathological changes, including inflammatory cell infiltration and architectural destruction of mammary gland ducts; on PID 9, the control quarters also developed mild mastitis and histopathological changes. Throughout the experimental period, the quarters of the negative control cow were clinically and pathologically normal. The M. leachii antigen was detected by IHC in the mammary tissues of the inoculated quarters as a weak signal on PID 6 and as a strong signal on PID 9; on PID 9, the M. leachii IHC signal was also detected in mammary gland epithelial cells of the control quarters of the inoculated cattle. The M. leachii antigen was not detected in the mammary tissues from the quarters of the negative control cow on PID 9. In conclusion, direct histological and immunohistochemical evidence confirmed that M. leachii causes clinical bovine mastitis through histopathological lesions induced by the invasion of the pathogen into mammary gland cells and inflammatory cell infiltration

G. lucidum is a typical representative of wood-rotting polypores of the Ganodermataceae family (Basidiomycetes). In Russia, G. lucidum is predominantly found in southern regions: in Stavropol and Krasnodar krais, Northern Caucasus, as well as in Altai taiga in logging areas. In this study we investigated the phylogeny of G. lucidum specimens from Altai based on the ITS1 ribosomal spacer, and compared them to reishi from other regions of the world. We also studied the phytochemical content of reishi fruit bodies. Results of the screening suggest that ethanol fractions contain mostly flavonoids, phenols, and coumarins; water fractions are dominated by tannins, carbohydrates, and coumarins; and hexane and ethyl acetate extracts, by terpenoids. The main fatty acids were palmitic, oleic, linoleic, and linolenic acids. We found that fruit bodies of Altai G. lucidum contained 32.4 mg of phenols per 1 g of extract (in pyrocatechol equivalent), while flavonoids made up 11.1 mg per g (in quercetin equivalent). Polysaccharide content was 10.72% of the absolutely dry substance.

Objective: The aim of the study wasto isolate bacterial consortium from the effluent contaminated site that is used in the mineralizing both natural rubber and synthetic rubber, to optimise the growth conditions for efficient mineralisation and to biochemically characterise and to use 16s RNA sequencing for identifying the bacterial strains.

Materials and Methods: Natural rubber mineralizing bacterial consortium was isolated from effluent contaminated soil. The mineralisation study was performed for five days at every 24 h interval. Optimization studies were performed with different parameters such as varying concentrations of latex, pH, carbon sources, nitrogen sources, mixed carbon and nitrogen source and different temperature. The bacterial consortium mineralizing nr latex was used to mineralize Synthetic Rubber Gloves (SRG) using the same medium for 40 days at every 5 days interval. Effect of pre-treatment was studied by pre-treating the SRG with acetone and exposing it to sunlight. Mineralisation of the Rubber was confirmed by spectrophotometric and Fourier Transform Infra-Red
(FTIR) studies.

Results: Isolated organism was identified as Enterobater cloacae, Microbacterium laevaniformans and Methylobacterium rhodesianum. Maximum mineralisation of (1.66x10-4) was shown on the 4th day of incubation. Conformation of NR degradation was done by FTIR analysis that shows the presence of aldehyde and ketone produced due to bacterial degradation. The parameters giving optimum results were concentration of latex -1%, pH- 8.5, carbon source- Xylose, nitrogen source - Ammonium Nitrate, temperature- 37°C. Maximum mineralisation of synthetic rubber was shown on the 20th day (1.3x10-4). Among the pre-treated and the untreated samples most prominent distortions were visible on the surface of the sunlight sample when visualized under
scanning electron microscopy.

Conclusion: From the present investigation, it can be concluded that the isolated bacterial consortium containing the strains Enterobater cloacae, Microbacterium laevaniformans and Methylobacterium rhodesianum were able to mineralize natural rubber as well as synthetic rubber. This could be applied in the removal of waste rubber products present in the environment.

Dermatophytes are a group of fungi that can invade keratinized tissues of humans and other animals and produce an infection called Dermatophytosis. As chitosan possesses antimicrobial activity, it can potentially be used to treat dermatophytic infections. The main objective of this work was therefore, to evaluate the antifungal activity of chitosan upon some dermatophytes, namely Microsporum canis and Trychophyton rubrum. In view of this, Minimum Inhibitory (MICs) and Minimum Fungicidal Concentrations (MFCs) of chitosans upon the fungi were determined. Moreover, in order to understand the effect of chitosan on fungal activity, hair was infected with these fungi in the presence and absence of chitosan and Scanning Electron Microscopy (SEM) images were obtained and analyzed. Lastly, keratin-azure was used as substrate to evaluate the effect of chitosan on keratin degradation by M. canis and T. rubrum. The results showed that chitosan possesses antifungal activity against T. rubrum and M. canis, presenting MICs and MFCs ranging from 1.1 to 2.2 mg/mL. The antifungal activity of chitosan is concentration dependent. The analysis of SEM images of hair infected with these dermatophytes revealed that chitosan seems to have a protective effect on the hair, reducing the extent of damage when compared to the control. Chitosan also displayed important activity in preventing proteases’ action and in preventing hair damage. Based on the obtained results, it’s possible to conclude that chitosan showed relevant antifungal activity against dermatophytes, which opens good prospects to the use of chitosan as an alternative for the conventional fungal treatments.

A total of 9347 fungal and bacterial endophytes were isolated from the roots, stem and leaves of chia plant. Roots harbored more number of fungal endophytes than either stem or leaves whereas stem supported more number of bacterial endophytes than either roots or leaves. The nutritious plant supported more of gram negative compared to gram positive bacterial endophytes. The most common bacteria isolated were Pseudomonas Bacillus, and Cocci. The fungal endophytes isolated from root, stem and leaves of the chia plant showed the presence of Penincillium, Aspergillus, Fusarium, and Macrophomina spps. Dominant fungal endophyte was Aspergillus spp. which was found in all the plant parts instigated. Roots of the plant possessed maximum nitrogen fixers followed by stem and leaves. A proportion of 55% for the bacterial endophytes isolated from the plant chia plant were able to fix nitrogen whereas 25% were able to solubilize phosphorous. The phosphate solubilization efficiency was found to be highest for the Aspergillus spp at 83%.

Aims:
The objectives of this research work were isolation of Bifidobacteria from the human milk and its Probiotic characterization such as low pH, bile and in-vitro antimicrobial activity against diarrhea causing pathogen.

Methodology and Results:
In this research work, 47 bifidobacterial isolates were isolated from the human milk of the 50 lactating women and identified by using phenotypic methods. The isolates were examined in-vitro for their tolerance to unfavorable condition at low pH of 2 and 4 and at different concentrations of bile 0.3%, 0.5% and 1%. Further the isolates were tested for the antimicrobial activities by using diarrhea causing indicator stains such as E. coli, Salmonella enterica and Shigella boydii. Antibiotic susceptibility test was performed for the isolates which showed zone of inhibition in antimicrobial testing. Based on the result of in-vitro Probiotic test, the best four isolates Dbs18, Smk9, Smk4 and Smk5 were selected for further evaluation of tolerance test of phenol (0.1%, 0.2%, 0.4%), NaCl (5%, 8%, 12%). Auto aggregation and hydrophobicity assay were also done for the four selected isolates. In in-vitro test of low pH, out of 47 isolates only 14 isolates were able to grow whereas in bile tolerance assay most of the isolates grew well at 0.3% bile concentration but variability of growth of isolates were observed at 0.5% and 1% bile. In antimicrobial assay, 15 isolates out of 47 isolates showed antimicrobial activity after ruling out the inhibitory activity of low pH. In NaCl and phenol tolerance test all the four selected isolates were able to survive the different concentration of phenol and NaCl. The percentage of hydrophobicity and auto aggregation was highest in Dbs18 followed by Smk9 among the four isolates.

Conclusion, significance and impact of study:
Among the four isolates Dbs18 and Smk9 showed good hydrophobicity and auto aggregation ability. These bifidobacterial isolates Dbs18 and Smk9 are found to possess desirable Probiotic properties and will be selected for the in-vivo test and molecular identification will be done for the selected isolates. These bifidobacterial strains may act as a potential candidate of novel Probiotic strain isolated from human milk for the treatment of bacterial gastrointestinal diarrhea.

The enhancement of bioelectricity generation in the Microbial Fuel Cell (MFC) necessitated the introduction of exogenous compound (s) (i.e. mediators). The effect of 1ml of various synthetic exogenous mediators including dyes and metallorganics such as Ethylene Diamine Tetra Acid [EDTA], potassium ferricyanide [K3 Fe(CN)6 ], methylene blue [MB], neutral red [NR] and potassium permanganate [KMnO4 ] was investigated in a 21day study during electricity generation in an MFC. The maximum Power Density (PD) obtained without the addition of any mediator was 84.58mW/m2, while those MFCs which utilized mediators recorded higher energy yield. The highest power density and percentage energy contribution of 924.79mW/m2 (993.39%) was obtained using K3 Fe(CN)6, while values obtained with EDTA [803.71mW/m2 (850.24%)]; MB [340.45mW/m2 (302.52%)] and KMnO4 [192.14mW/m2 (121.17%)] as mediators were appreciably higher. Further study on the use of these mediators showed inhibitory effects with the % reduction of microbial load in the following trend as MB (4.96%) < EDTA (6.13%) < NR (11.67%) < Ferricyanide (19.16%) < KMnO4 (21.89%) when compared to the control. Although the application of mediators improved energy production, minimum inhibitory concentration of the mediators should be ascertained to prevent the eradication of electrogens during electricity production.

Microbial fuel cells (MFCs), which can be use bacterial cultures as biocatalyst for the conversion of chemical energy into the electricity from the biomass. The bacteria that can be able to synthesis the electron from biodegradation of organic content and transfer the electron are known as exoelectrogen. The objective of this study was to investigate the electricity generation from the extremophilic bacterium isolated from Lonar Lake (India). Oceanobacillus iheyensis BS1(2), an alkalophilic, Gram-positive, spore forming, was isolated from the anode of a lonar lake sediment MFC that was continuously operated under pH 10.0. Before the culture transfer in anode, strain Oceanobacillus iheyensis BS12 was aerobically cultivated in medium Horikoshi II medium. A totally fifty seven bacterial culture were isolated, from which BS12 was selected for the further investigation of MFC. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BS1(2) was affiliated with the genus Oceanobacillus. The experimental results performed that the strain BS1(2) was capable of utilizing organic acids and sugars as electron donors to generate electricity. The MFC was constructed and the electricity generation was measured after various intervals using various parameters, 644mV electricity was generated after 1h, but after 48h the electricity generation dramatically decreases 420mV. The effect of pH on MFC was also studied, pH enhanced electricity (644mV), indicating requirement of pH for bacterium BS12. The present studies, thus serve in finding the proximate values of these course features which basic consequence in optimum bioelectricity generation.