Curcuma longa L. (turmeric), Rosmarinus officinalis L. (rosemary), and Thymus vulgaris L. (thyme) extracts aid murine macrophages (RAW 264.7) to fight Streptococcus mutans during in vitro infection.

Finding an effective alternative way to aid defense cells to fight Streptococcus mutans was the main goal of this study. The effect of plant extracts from Curcuma longa L. (turmeric), Rosmarinus officinalis L. (rosemary), and Thymus vulgaris L. (thyme) was evaluated on murine macrophages (RAW 264.7) infected by S. mutans. Minimum inhibitory concentration (MIC) of the extracts was determined. Macrophages were infected by S. mutans and treated with each extract. From the supernatants, it was measured nitric oxide (NO) level. Posteriorly, RAW 264.7 were lysed to expose living and phagocytosed bacteria. Cytotoxicity was checked by lysosomal activity analysis, using neutral red assay. Each extract helped RAW 264.7 to eliminate S. mutans during infection, as observed by a significant bacterial reduction. Significant cell viability was also found. Besides, an increased production of NO was verified using R. officinalis L. and T. vulgaris L. extracts. The evaluated extracts demonstrated an effective action to assist RAW 264.7 to fight S. mutans during infection.

Titanium alloys: in vitro biological analyzes on biofilm formation, biocompatibility, cell differentiation to induce bone formation, and immunological response.

Biological effects of titanium (Ti) alloys were analyzed on biofilms of Candida albicans, Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans, and Streptococcus sanguinis, as well as on osteoblast-like cells (MG63) and murine macrophages (RAW 264.7). Standard samples composed of aluminum and vanadium (Ti-6Al-4V), and sample containing niobium (Ti-35Nb) and zirconium (Ti-13Nb-13Zr) were analyzed. Monomicrobial biofilms were formed on the Ti alloys. MG63 cells were grown with the alloys and the biocompatibility (MTT), total protein (TP) level, alkaline phosphatase (ALP) activity, and mineralization nodules (MN) formation were verified. Levels of interleukins (IL-1ß and IL-17), tumor necrosis factor alpha (TNF-α), and oxide nitric (NO) were checked, from RAW 264.7 cells supernatants. Data were statically analyzed by one-way analysis of variance (ANOVA) and Tukey's test, or T-test (P ≤ 0.05). Concerning the biofilm formation, Ti-13Nb-13Zr alloy showed the best inhibitory effect on E. faecalis, P. aeruginosa, and S. aureus. And, it also acted similarly to the Ti-6Al-4V alloy on C. albicans and Streptococcus spp. Both alloys were biocompatible and similar to the Ti-6Al-4V alloy. Additionally, Ti-13Nb-13Zr alloy was more effective for cell differentiation, as observed in the assays of ALP and MN. Regarding the stimulation for release of IL-1ß and TNF-α, Ti-35Nb and Ti-13Nb-13Zr alloys inhibited similarly the synthesis of these molecules. However, both alloys stimulated the production of IL-17. Additionally, all Ti alloys showed the same effect for NO generation. Thus, Ti-13Nb-13Zr alloy was the most effective for inhibition of biofilm formation, cell differentiation, and stimulation for release of immune mediators.

Antimicrobial activity of noncytotoxic concentrations of Salvia officinalis extract against bacterial and fungal species from the oral cavity.

The use of medicinal plants can be an alternative method for the control of microorganisms responsible for human infections. This study evaluated the antimicrobial activity of Salvia officinalis Linnaeus (sage) extract on clinical samples isolated from the oral cavity and reference strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Candida albicans, Candida tropicalis, and Candida glabrata. In addition, testing assessed the cytotoxic effect of S officinalis on murine macrophages (RAW 264.7). Minimum inhibitory, minimum bactericidal, and minimum fungicidal concentrations of S officinalis extract were determined by broth microdilution method in 60 microbial samples. The cytotoxicity was checked by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The quantities of the proinflammatory cytokines interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) produced by RAW 264.7 were analyzed by an enzyme-linked immunosorbent assay. An S officinalis concentration of 50.0 mg/mL was effective against all microorganisms. Regarding cytotoxicity, the groups treated with 50.0-, 25.0-, and 12.5-mg/mL concentrations of S officinalis presented cell viability statistically similar to that of the control group, which was 100% viable. The production of IL-1ß and TNF-α was inhibited at a 50.0-mg/mL concentration of S officinalis. Thus, S officinalis extract presented antimicrobial activity on all isolates of Staphylococcus spp, S mutans, and Candida spp. No cytotoxic effect was observed, as demonstrated by the survival of RAW 264.7 and inhibition of IL-1ß and of TNF-α.

Rosmarinus officinalis L. (rosemary) as therapeutic and prophylactic agent.

Rosmarinus officinalis L. (rosemary) is a medicinal plant native to the Mediterranean region and cultivated around the world. Besides the therapeutic purpose, it is commonly used as a condiment and food preservative. R. officinalis L. is constituted by bioactive molecules, the phytocompounds, responsible for implement several pharmacological activities, such as anti-inflammatory, antioxidant, antimicrobial, antiproliferative, antitumor and protective, inhibitory and attenuating activities. Thus, in vivo and in vitro studies were presented in this Review, approaching the therapeutic and prophylactic effects of R. officinalis L. on some physiological disorders caused by biochemical, chemical or biological agents. In this way, methodology, mechanisms, results, and conclusions were described. The main objective of this study was showing that plant products could be equivalent to the available medicines.

Thymus vulgaris L. and thymol assist murine macrophages (RAW 264.7) in the control of in vitro infections by Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans.

Microorganisms are capable to combat defense cells by means of strategies that contribute to their stabilization and proliferation in invaded tissues. Frequently antimicrobial-resistant strains appear; therefore, alternative methods to control them must be investigated, for example, the use of plant products. The capacity of the thyme extract (Thymus vulgaris L.) and phytocompound thymol in the control of in vitro infections by Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans in murine macrophages (RAW 264.7) was evaluated. Minimal inhibitory concentrations (MIC) of the plant products were used. The effect of these MIC were analyzed in the assays of phagocytosis and immunoregulation by analysis of the production of cytokines (IL-1ß, TNF-α, and IL-10) and nitric oxide (NO). The plant products effectively assisted the macrophages in the phagocytosis of microorganisms, presenting significant reductions of S. aureus and P. aeruginosa. The macrophages also regulated the production of inflammatory mediators in the infections by S. aureus, P. aeruginosa, and C. albicans. In addition, thyme provided a satisfactory effect in response to the bacterial infections, regarding generation of NO. Thus, the effectiveness of the thyme and thymol to control in vitro infections by S. aureus, P. aeruginosa, and C. albicans was observed. HIGHLIGHTS: Phagocytosis of S. aureus by RAW 264.7 was enhanced with thymol Thyme enhanced the phagocytosis of P. aeruginosa by RAW 264.7 Plant products provided immunoregulation of inflammatory cytokines Production of nitric oxide was improved with the treatments in bacterial infections.

Biological activities of Rosmarinus officinalis L. (rosemary) extract as analyzed in microorganisms and cells.

R. officinalis L. is an aromatic plant commonly used as condiment and for medicinal purposes. Biological activities of its extract were evaluated in this study, as antimicrobial effect on mono- and polymicrobial biofilms, cytotoxicity, anti-inflammatory capacity, and genotoxicity. Monomicrobial biofilms of Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans and Pseudomonas aeruginosa and polymicrobial biofilms composed of C. albicans with each bacterium were formed in microplates during 48 h and exposed for 5 min to R. officinalis L. extract (200 mg/mL). Its cytotoxic effect was examined on murine macrophages (RAW 264.7), human gingival fibroblasts (FMM-1), human breast carcinoma cells (MCF-7), and cervical carcinoma cells (HeLa) after exposure to different concentrations of the extract, analyzed by MTT, neutral red (NR), and crystal violet (CV) assays. The anti-inflammatory activity was evaluated on RAW 264.7 non-stimulated or stimulated by lipopolysaccharide (LPS) from Escherichia coli and treated with different concentrations of the extract for 24 h. Interleukin-1 beta (IL-1ß) and tumor necrosis factor alpha (TNF-α) were quantified by ELISA. Genotoxicity was verified by the frequency of micronuclei (MN) at 1000 cells after exposure to concentrations of the extract for 24 h. Data were analyzed by T-Test or ANOVA and Tukey Test ( P ≤ 0.05). Thus, significant reductions in colony forming units per milliliter (CFU/mL) were observed in all biofilms. Regarding the cells, it was observed that concentrations ≤ 50 mg/mL provided cell viability of above 50%. Production of proinflammatory cytokines in the treated groups was similar or lower compared to the control group. The MN frequency in the groups exposed to extract was similar or less than the untreated group. It was shown that R. officinalis L. extract was effective on mono- and polymicrobial biofilms; it also provided cell viability of above 50% (at ≤ 50 mg/mL), showed anti-inflammatory effect, and was not genotoxic. Impact statement Rosmarinus officinalis L. extract effectively contributed to in vitro control of important species of microorganisms such as Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, and Pseudomonas aeruginosa in mono- and polymicrobial biofilms that are responsible for several infections in oral cavity as in other regions of the body. Furthermore, this extract promoted also cell viability above 50% at concentrations ≤ 50 mg/mL, excellent anti-inflammatory effect, showing inhibition or reduction of the synthesis of proinflammatory cytokines, being also non-genotoxic to cell lines studied. Thus, this extract may be a promising therapeutic agent that can be added in some medical and dental formulations such as toothpastes, mouthwashes, irrigating root canals, ointments, soaps, in order to control pathogenic microorganisms and biofilms, with anti-inflammatory effect and absence of cytotoxic and genotoxic.

Control of microorganisms of oral health interest with Arctium lappa L. (burdock) extract non-cytotoxic to cell culture of macrophages (RAW 264.7).

OBJECTIVES: To evaluate the antimicrobial activity of Arctium lappa L. extract on Staphylococcus aureus, S. epidermidis, Streptococcus mutans, Candida albicans, C. tropicalis and C. glabrata. In addition, the cytotoxicity of this extract was analyzed on macrophages (RAW 264.7). DESIGN: By broth microdilution method, different concentrations of the extract (250-0.4 mg/mL) were used in order to determine the minimum microbicidal concentration (MMC) in planktonic cultures and the most effective concentration was used on biofilms on discs made of acrylic resin. The cytotoxicity A. lappa L. extract MMC was evaluated on RAW 264.7 by MTT assay and the quantification of IL-1ß and TNF-α by ELISA. RESULTS: The most effective concentration was 250 mg/mL and also promoted significant reduction (log10) in the biofilms of S. aureus (0.438 ± 0.269), S. epidermidis (0.377 ± 0.298), S. mutans (0.244 ± 0.161) and C. albicans (0.746 ± 0.209). Cell viability was similar to 100%. The production of IL-1ß was similar to the control group (p>0.05) and there was inhibition of TNF-α (p<0.01). CONCLUSIONS: A. lappa L. extract was microbicidal for all the evaluated strains in planktonic cultures, microbiostatic for biofilms and not cytotoxic to the macrophages.

Cytotoxicity of Brazilian plant extracts against oral microorganisms of interest to dentistry.

BACKGROUND: With the emergence of strains resistant to conventional antibiotics, it is important to carry studies using alternative methods to control these microorganisms causing important infections, such as the use of products of plant origin that has demonstrated effective antimicrobial activity besides biocompatibility. Therefore, this study aimed to evaluate the antimicrobial activity of plant extracts of Equisetum arvense L., Glycyrrhiza glabra L., Punica granatum L. and Stryphnodendron barbatimam Mart. against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Candida albicans, Candida tropicalis, and Candida glabrata, and to analyze the cytotoxicity of these extracts in cultured murine macrophages (RAW 264.7). METHODS: Antimicrobial activity of plant extracts was evaluated by microdilution method based on Clinical and Laboratory Standards Institute (CLSI), M7-A6 and M27-A2 standards. The cytotoxicity of concentrations that eliminated the microorganisms was evaluated by MTT colorimetric method and by quantification of proinflammatory cytokines (IL-1ß and TNF-α) using ELISA. RESULTS: In determining the minimum microbicidal concentration, E. arvense L., P. granatum L., and S. barbatimam Mart. extracts at a concentration of 50 mg/mL and G. glabra L. extract at a concentration of 100 mg/mL, were effective against all microorganisms tested. Regarding cell viability, values were 48% for E. arvense L., 76% for P. granatum L, 86% for S. barbatimam Mart. and 79% for G. glabra L. at the same concentrations. About cytokine production after stimulation with the most effective concentrations of the extracts, there was a significant increase of IL-1ß in macrophage cultures treated with S. barbatimam Mart. (3.98 pg/mL) and P. granatum L. (7.72 pg/mL) compared to control (2.20 pg/mL) and a significant decrease of TNF-α was observed in cultures treated with G. glabra L. (4.92 pg/mL), S. barbatimam Mart. (0.85 pg/mL), E. arvense L. (0.83 pg/mL), and P. granatum L. (0.00 pg/mL) when compared to control (41.96 pg/mL). CONCLUSIONS: All plant extracts were effective against the microorganisms tested. The G. glabra L. extract exhibited least cytotoxicity and the E. arvense L. extract was the most cytotoxic.