In Vitro Antibacterial, Anti-Adhesive and Anti-Biofilm Activities of Krameria lappacea (Dombey) Burdet & B.B. Simpson Root Extract against Methicillin-Resistant Staphylococcus aureus Strains.

Methicillin-resistant Staphylococcus aureus (MRSA) represents a serious threat to public health, due to its large variety of pathogenetic mechanisms. Accordingly, the present study aimed to investigate the anti-MRSA activities of Krameria lappacea, a medicinal plant native to South America. Through Ultra-High-Performance Liquid Chromatography coupled with High-Resolution Mass spectrometry, we analyzed the chemical composition of Krameria lappacea root extract (KLRE). The antibacterial activity of KLRE was determined by the broth microdilution method, also including the minimum biofilm inhibitory concentration and minimum biofilm eradication concentration. Besides, we evaluated the effect on adhesion and invasion of human lung carcinoma A549 cell line by MRSA strains. The obtained results revealed an interesting antimicrobial action of this extract, which efficiently inhibit the growth, biofilm formation, adhesion and invasion of MRSA strains. Furthermore, the chemical analysis revealed the presence in the extract of several flavonoid compounds and type-A and type-B proanthocyanidins, which are known for their anti-adhesive effects. Taken together, our findings showed an interesting antimicrobial activity of KLRE, giving an important contribution to the current knowledge on the biological activities of this plant.

In vitro evaluation of biological activities of Orobanche crenata Forssk. leaves extract.

Orobanche crenata Forssk. (Orobanchaceae) is a holoparasitic plant noxious to legumes. Orobanchaceae are well known in traditional medicine for their hypotensive, antihyperglycemic, antispasmodic, analgesic and antimicrobial effects. In this work, the biological activities of the acetonic leaves extract were evaluated. Qualitative chemical analysis was determined through thin layer chromatography. Total phenols and flavonoids content was obtained by the Folin-Ciocalteu and the Aluminium chloride colorimetric methods, respectively. The antimicrobial activity was performed by the broth microdilution method. The extract showed antibacterial activity, particularly against Gram-positive strains, with MIC ranging from 376.00 to 3011.00 µg/ml. Besides, it exhibited antifungal effects on Candida spp. with MIC ranging from 94.10 to 3011.00 µg/ml. In addition, O. crenata inhibited superoxide anion formation and showed a DPPH quenching capacity, particularly at 80 µg/ml. Interestingly, our results are promising thus indicating the importance of O. crenata as a significant source of biologically active natural compounds.

Combined systemic (fluconazole) and topical (metronidazole + clotrimazole) therapy for a new approach to the treatment and prophylaxis of recurrent candidiasis.

Recurrent vulvovaginal candidiasis (RVVC) is an important pathological and infectious condition that can greatly impact a woman's health and quality of life. Clinical and epidemiological studies show that different types of therapies are able to eliminate the signs and symptoms of mycotic vaginitis in the acute phase, but so far none of these has proved able to significantly reduce the risk of long-term recurrence. In this review, based on the available literature and original data from a preliminary in-vitro microbiological study on the compatibility between fluconazole, clotrimazole and metronidazole a new therapeutic approach to RVVC is discussed and presented. The treatment proposed is a combined scheme using both systemic antimicrobial drug therapy with oral fluconazole 200 mg and topical drug therapy using the association metronidazole 500 mg and clotrimazole 100 mg (vaginal ovules) with adjuvant oral probiotic therapy. In detail, at the time of diagnosis in the acute symptom phase, we propose the following treatment scheme: fluconazole 200 mg on day 1, 4, 11, 26, then 1 dose/month for 3 months at the end of the menstrual cycle; plus metronidazole/clotrimazole ovules 1/day for 6 days the first week, then 1 ovule/day for 3 days the week before the menstrual cycle for 3 months; plus probiotic 1 dose/day for 10 days for 3 months starting from the second month to the end of the menstrual cycle. This scheme aims to address the recurrent infection aggressively from the outset by attempting not only to treat acute symptoms, but also to prevent a new event by countering many of the potential risk factors of recurrence, such as the intestinal Candida reservoir, the mycotic biorhythm, the formation of biofilm, the phenotype switching and the presence of infections complicated by the presence of C. non albicans or G. Vaginalis, without interfering, but rather favoring the restoration of the vaginal lactobacillus species. Future clinical studies will be useful to confirm the proposed scheme.

Effects of a new combination of plant extracts plus d-mannose for the management of uncomplicated recurrent urinary tract infections.

Urinary tract infections (UTIs) are an economic burden for public health. The increasing prevalence of resistant bacteria which cause UTIs may be related to the inappropriate prescription of antibiotics. The aim of this preliminary study was to evaluate whether three different combinations of plant extracts plus d-mannose are effective in preventing the recurrence of UTIs. Three groups of patients received three combinations of plant extracts in conjunction with d-mannose. These were: berberine, arbutin and birch (group A); berberine, arbutin, birch and forskolin (group B); and proanthocyanidins (group C). The clinical recurrence of cystitis at the end of treatment and during follow-up was determined by comparison with baseline measurements using the microbiological assessment of urine samples, vaginal swabs and vaginal smear slides. Patients in groups A and B had a lower incidence of episodes of recurrent cystitis during treatment and follow-up, samples with a significantly lower median bacterial load and a reduction of the grade of lactobacillary flora compared to patients in group C.

Fosfomycin tromethamine in uncomplicated urinary tract infections: a clinical study.

The aim of our study was to verify if the empiric therapy with a single dose of 3 g fosfomycin tromethamine in patients with uncomplicated urinary tract infections (UTIs) was able to clinically resolveand to microbiologically eradicate the infection. A total of 387 out of the 400 patients (274 cases with acute and 113 cases with recurrent uncomplicated UTIs) were enrolled in the clinical study. Clinical and microbiological assessments were performed before and at 8-10 days after the administration. At follow-up high clinical recovery (88.9%) and bacteriological (94.9%) eradication rates were achieved. Gastrointestinal side effects were found in only 4.3% of patients. In conclusion, a single-dose administration regimen of fosfomycin tromethamine should be encouraged as a first choice of drug therapy for uncomplicated UTIs.