A tangible prospect for the treatment of gingivitis using a potentially probiotic strain Lactobacillus plantarum MK06 isolated from traditional dairy products: a triple blind randomized clinical trial.

BACKGROUND: Frequent bacterial plaque buildup at the gingival margin and crevice can provoke an inflammatory reaction in gingival tissues which manifests as gingivitis. Probiotics could serve as a beneficial complementary therapy for treating gingival inflammation. The main aim of this research was to investigate the effect of the Lactobacillus plantarum MK06 probiotic strain on the treatment of gingivitis. METHODS: Patients with gingivitis, who were referred to a private clinic and were systematically healthy, were included in this randomized, triple-blind, placebo-controlled trial. They were instructed to use either placebo or Lactobacillus plantarum suspensions for one minute two times a day after tooth-brushing for four weeks. Then, the clinical parameters of gingivitis, including plaque index (PI), gingival index (GI), bleeding on probing (BOP), and oral hygiene index (OHI-s), were measured in the first, second, and fourth weeks. A total of forty-two patients were randomly assigned to the experimental (n = 21) and control (n = 21) groups. The mean age of the experimental and control groups was 29.10 and 28.48, respectively. RESULTS: The mean scores of BOP, GI, PI, and OHI-s reduced over time in both the control and test groups. However, according to the Mann-Whitney test, the difference between the two groups was not significant at the same time intervals (P ≥ 0.05) and only GI showed a significant difference in the fourth week (GI-3, P = 0.006). Nevertheless, the experimental group experienced a higher overall reduction rate than the control group. The BOP, GI, PI, and OHI-s scores decreased by 0.081, 0.204, 0.186, and 0.172 times in the second week, respectively, resulting from the interaction of time and the intervention, which considerably diminished these indices. CONCLUSION: This study shows the potential of the probiotic Lactobacillus plantarum MK06 suspension as a promoting therapeutic adjuvant in the treatment of gingivitis.

Desertifilum sp. EAZ03 cell extract as a novel natural source for the biosynthesis of zinc oxide nanoparticles and antibacterial, anticancer and antibiofilm characteristics of synthesized zinc oxide nanoparticles.

AIMS: The use of cyanobacterial cell extracts for the synthesis of zinc oxide nanoparticles (ZnO NPs) seems to be superior to other methods of synthesis because of its a green, environmentally friendly and low-cost approach. In this study, the cell extract of a newly characterized cyanobacterial strain Desertifilum sp. EAZ03 was used for the biosynthesis of ZnO NPs. The antimicrobial, antibiofilm and anticancer activities of the biosynthesized ZnO NPs (hereinafter referred to as CED-ZnO NPs) were examined as well. METHODS AND RESULTS: UV-Vis spectroscopy analysis of CED-ZnO NPs showed an absorbance band at 364 nm, and powder X-ray diffraction analysis confirmed the purity of the synthesized nanoparticles. The analyses of scanning electron microscopy and transmission electron microscopy images revealed that CED-ZnO NPs were rod-shaped with a size of 88 nm. The study of the biological features of CED-ZnO NPs showed a significant antimicrobial potential against the bacterial strains tested. CED-ZnO NPs were able to impede the biofilm formation by Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa up to 80%, 89% and 85%, respectively. The nanoparticles also showed 69%, 70% and 62% degrading activity against S. aureus, E. coli and P. aeruginosa 1-day-old biofilms, respectively. The antibiofilm activity of the synthesized nanoparticles was investigated by confocal laser scanning microscopy. The MTT assay showed that CED-ZnO NPs, at a concentration of 100 µg/ml, had less cytotoxicity towards normal lung (MRC-5) cells, at the half, compared to cancerous lung alveolar epithelial (A549) cells. The minimum inhibitory concentration and minimum bactericidal concentration values of CED-ZnO NPs against E. coli, P. aeruginosa and S. aureus were 1500, 2000 and 32 µg/ml, and 2500, 3500 and 64 µg/ml, respectively. CONCLUSIONS: The multifunctional CED-ZnO NPs seem to be promising for possible applications in the therapeutic and pharmaceutical industries. SIGNIFICANCE AND IMPACT OF THE STUDY: This study proposes a new approach for the biosynthesis of zinc oxide nanoparticles using a newly characterized cyanobacterial strain Desertifilum sp. EAZ03. The considerable antimicrobial, antibiofilm and anticancer activities of the biosynthesized zinc oxide nanoparticles further emphasize the emerging role of microbial systems in the green synthesis of metal oxide nanoparticles.

Biosurfactant-producing bacterium, Pseudomonas aeruginosa MA01 isolated from spoiled apples: physicochemical and structural characteristics of isolated biosurfactant.

An extensive investigation was conducted to isolate indigenous bacterial strains with outstanding performance for biosurfactant production from different types of spoiled fruits, food-related products and food processing industries. An isolate was selected from 800 by the highest biosurfactant yield in soybean oil medium and it was identified by 16S rRNA and the two most relevant hypervariable regions of this gene; V3 and V6 as Pseudomonas aeruginosa MA01. The isolate was able to produce 12 g/l of a glycolipid-type biosurfactant and generally less efficient to emulsify vegetable oils compared to hydrocarbons and could emulsify corn and coconut oils more than 50%. However, emulsification index (E(24)) of different hydrocarbons including hexane, toluene, xylene, brake oil, kerosene and hexadecane was between 55.8% and 100%. The surface tension of pure water decreased gradually with increasing biosurfactant concentration to 32.5 mNm(-1) with critical micelle concentration (CMC) value of 10.1mg/l. Among all carbon substrates examined, vegetable oils were the most effective on biosurfactant production. Two glycolipid fractions were purified from the biosurfactant crude extracts, and FTIR and ES-MS were used to determine the structure of these compounds. The analysis indicated the presence of three major monorhamnolipid species: R(1)C(10)C(10), R(1)C(10)C(12:1), and R(1)C(10)C(12); as well as another three major dirhamnolipid species: R(2)C(10)C(10), R(2)C(10)C(12:1), and R(2)C(10)C(12). The strain sweep experiment for measuring the linear viscoelastic of biosurfactant showed that typical behavior characteristics of a weak viscoelastic gel, with storage modulus greater than loss modulus at all frequencies examined, both showing some frequency dependence.

Enhanced phenol degradation by Pseudomonas sp. SA01: gaining insight into the novel single and hybrid immobilizations.

In this work, Pseudomonas sp. SA01 cells were immobilized in a series of singular and hybrid immobilization techniques to achieve enhanced phenol removal. The singular immobilization strategies consisted of various concentrations of alginate (2-4%) and pectin (3-5%), while the hybrid strategies incorporated polyvinyl alcohol (PVA)-alginate and glycerol-alginate beads and alginate-chitosan-alginate (ACA) capsules. Immobilization protected cells against phenol and resulted in remarkable reduction (65%) in degradation time by cells immobilized in either alginate (3%) beads, in a hybrid PVA-alginate beads, or in ACA capsules compared to freely suspended cells. Cells immobilized in PVA-alginate and ACA provided the best performance in experiments using elevated phenol concentrations, up to 2000 mg/L, with complete degradation of 2000 mg/L phenol after 100 and 110 h, respectively. Electron microscopy examination indicated that cell loading capacity was increased in PVA-alginate hybrid beads through reduced cell leakage, resulting in higher activity of PVA-alginate hybrid beads compared to all other immobilization methods.

An efficient biosurfactant-producing bacterium Pseudomonas aeruginosa MR01, isolated from oil excavation areas in south of Iran.

A bacterial strain was isolated and cultured from the oil excavation areas in tropical zone in southern Iran. It was affiliated with Pseudomonas. The biochemical characteristics and partial sequenced 16S rRNA gene of isolate, MR01, was identical to those of cultured representatives of the species Pseudomonas aeruginosa. This bacterium was able to produce a type of biosurfactant with excessive foam-forming properties. Compositional analysis revealed that the extracted biosurfactant was composed of high percentages lipid ( approximately 65%, w/w) and carbohydrate ( approximately 30%, w/w) in addition to a minor fraction of protein ( approximately 4%, w/w). The best production of 2.1g/l was obtained when the cells were grown on minimal salt medium containing 1.2% (w/v) glucose and 0.1% (w/v) ammonium sulfate supplemented with 0.1% (w/v) isoleucine at 37 degrees C and 180rpm after 2 days. The optimum biosurfactant production pH value was found to be 8.0. The MR01 could reduce surface tension to 28mN/m and emulsified hexadecane up to E24 approximately 70. The results obtained from time course study indicated that the surface tension reduction and emulsification potential was increased in the same way to cell growth. However, maximum biosurfactant production occurred and established in the stationary growth phase (after 84h). Fourier Transform Infrared spectrum of extracted biosurfactant indicates the presence of carboxyl, amine, hydroxyl and methoxyl functional groups. Thermogram of biosurfactant demonstrated three sharp endothermic peaks placing between 200 and 280 degrees C. The core holder flooding experiments demonstrated that the oil recovery efficiencies varied from 23.7% to 27.1% of residual oil.