Antibacterial activity of medicinal plants against uropathogenic Escherichia coli

Urinary tract infections (UTIs) are one of the most common bacterial infections with uropathogenic Escherichia coli (UPEC) being the most prevalent causative agent in both complicated and uncomplicated UTIs. Antibiotic resistance among UPEC has been already demonstrated against a wide variety of antibiotics and the situation is continuing to deteriorate increasing the rate of recurrence and the difficulty of treatment and prophylaxis. Recently, a big attention has been paid to non-antibiotic approaches as an alternative to conventional antibiotics. Among many strategies, phytotherapy has gained a special attention worldwide. Herbal remedies have been used in traditional medicine since ancient times and they are well known for their effectiveness in treating many health conditions including UTIs. Researches are conducted continuously to validate the use of many medicinal plants against UPEC, investigate their mechanisms of action, and determine their active constituents. Our extensive review of the recent literature revealed that many phytochemicals are shown to target and inhibit a wide variety of bioprocesses in UPEC, such as adhesion, motility, biofilm formation, and quorum sensing. Such natural approaches are very promising in confronting the antibiotic resistance of UPEC and can be further used to develop plant-based strategies and pharmaceutical products to treat and prevent UTIs caused by UPEC.

Cranberry extract initiates intrinsic apoptosis in HL-60 cells by increasing BAD activity through inhibition of AKT phosphorylation

Background

Cranberry has been studied as a potential anticancer agent as it is capable of inducing apoptosis within cancer cells. The aim of this study was to better define the mechanism by which cranberry triggers apoptosis in HL-60 cells.

Methods

The study was carried on cranberry extracts (CB). Anti-apoptotic B-cell lymphoma-2 (BCL-2) and pro-apoptotic BCL-2-associated death promoter death (BAD) proteins in cell lysates were detected through Western blotting techniques. Equivalent protein loading was confirmed through anti-α-tubulin antibody.

Results

The results showed that treatment of HL-60 cells with CB causes a significant increase in the levels of caspase-9 and caspases-3/7 and increased mitochondrial outer membrane permeability, leading to the release of cytochrome C and Smac. These apoptotic events were associated with a significant decrease in protein kinase B (AKT) phosphorylation, which caused significant increase in BAD de-phosphorylation and promoted a sequence of events that led to intrinsic apoptosis.

Conclusion

The study findings have described a molecular framework for CB-initiated apoptosis in HL-60 cells and suggested a direction for future in vivo studies investigating the anticancer effect of cranberry.

Rapid Screening of Natural Plant Extracts with Calcium Diacetate for Differential Effects Against Foodborne Pathogens and a Probiotic Bacterium

This study focused on advancing a rapid turbidimetric bioassay to screen antimicrobials using specific cocktails of targeted foodborne bacterial pathogens. Specifically, to show the relevance of this rapid screening tool, the antimicrobial potential of generally recognized as safe calcium diacetate (DAX) and blends with cranberry (NC) and oregano (OX) natural extracts was evaluated. Furthermore, the same extracts were evaluated against beneficial lactic acid bacteria. The targeted foodborne pathogens evaluated were Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes, and Staphylococcus aureus using optimized initial cocktails (∼10⁸ colony-forming unit/mL) containing strains isolated from human food outbreaks. Of all extracts evaluated, 0.51% (w/v) DAX in ethanol was the most effective against all four pathogens. However, DAX when reduced to 0.26% and with added blends from ethanol extractions consisting of DAX:OX (3:1), slightly outperformed or was equal to same levels of DAX alone. Subculture of wells in which no growth occurred after 1 week indicated that all water and ethanol extracts were bacteriostatic against the pathogens tested. All the targeted antimicrobials had no effect on the probiotic organism Lactobacillus plantarum. The use of such rapid screening methods combined with the use of multistrain cocktails of targeted foodborne pathogens from outbreaks will allow rapid large-scale screening of antimicrobials and enable further detailed studies in targeted model food systems.

Cranberry Products for the Prophylaxis of Urinary Tract Infections in Pediatric Patients

Objective: To evaluate the existing data regarding the use of cranberry products for the prevention of urinary tract infections (UTIs) in pediatric patients. Data Sources: A literature search of Medline databases from 1966 to June 2015 was conducted. Study Selection and Data Extraction: The databases were searched using the terms “pediatrics,” “children,” “cranberry,” “cranberry juice,” and “urinary tract infections.” The identified trials were then searched for additional references applicable to this topic. Data Synthesis: A total of 8 clinical trials were identified that examined the use of cranberry products, mostly juice, for the prevention of UTIs in children. Three trials examined the use in otherwise healthy children. Five trials examined the use in pediatric patients with underlying urogenital abnormalities of which 2 compared cranberry to antibiotics. In healthy pediatric patients, cranberry use was associated with a reduction in the overall number of UTIs and a decrease in the number of antibiotic days per year for UTI treatment. In patients with urogenital abnormalities, results were conflicting, with some studies showing no reduction in UTIs compared with placebo, but others demonstrating a significant reduction. However, cranberry products had similar efficacy when compared with both cefaclor and trimethoprim. All studies used a wide variety of doses and frequencies of cranberry, making specific product recommendations difficult. Conclusions: Cranberry appears effective for the prevention of UTIs in otherwise healthy children and is at least as effective as antibiotics in children with underlying urogenital abnormalities. However, recommendations for cranberry dosing and frequency cannot be confidently made at this time. Larger, well-designed trials are recommended.

Interactions between cranberries and fungi: the proposed function of organic acids in virulence suppression of fruit rot fungi

Cranberry fruit are a rich source of bioactive compounds that may function as constitutive or inducible barriers against rot-inducing fungi. The content and composition of these compounds change as the season progresses. Several necrotrophic fungi cause cranberry fruit rot disease complex. These fungi remain mostly asymptomatic until the fruit begins to mature in late August. Temporal fluctuations and quantitative differences in selected organic acid profiles between fruit of six cranberry genotypes during the growing season were observed. The concentration of benzoic acid in fruit increased while quinic acid decreased throughout fruit development. In general, more rot-resistant genotypes (RR) showed higher levels of benzoic acid early in fruit development and more gradual decline in quinic acid levels than that observed in the more rot-susceptible genotypes. We evaluated antifungal activities of selected cranberry constituents and found that most bioactive compounds either had no effects or stimulated growth or reactive oxygen species (ROS) secretion of four tested cranberry fruit rot fungi, while benzoic acid and quinic acid reduced growth and suppressed secretion of ROS by these fungi. We propose that variation in the levels of ROS suppressive compounds, such as benzoic and quinic acids, may influence virulence by the fruit rot fungi. Selection for crops that maintain high levels of virulence suppressive compounds could yield new disease resistant varieties. This could represent a new strategy for control of disease caused by necrotrophic pathogens that exhibit a latent or endophytic phase.

Deacidification of cranberry juice by electrodialysis with bipolar membranes

Cranberry is recognized for its many benefits on human health; however, its high acidity may be a limiting factor for its consumption. This study aimed to investigate the deacidification of cranberry juice using a two simultaneous step electrodialysis with bipolar membranes (EDBM) process. In step 1 (deacidification), during the 6 h treatment, the pH of the juice increased from 2.47 to 2.71 and a deacidification rate of 22.84% was obtained, whereas in step 2 (pH lowering) the pH of juice 2 was almost stable. Citric, quinic, and malic acid were extracted with a maximum of 25% and were mainly transferred to the KCl 2 fraction. A significant loss of anthocyanins in juice 2 (step 2) was observed, due to their oxidation by oxygen incorporated by the centrifugal pump. This also affected its coloration. The first step of the EDBM process was successful for cranberry juice deacidification and could be improved by increasing the number of membranes stacked.

Comparing procyanidins in selected Vaccinium species by UHPLC-MS(2) with regard to authenticity and health effects

Cranberry procyanidins have been associated with an effect against urinary tract infections (UTI) for decades, and European health claims are requested. This study compares the procyanidin profiles and concentrations of American cranberry ( Vaccinium macrocarpon Ait.), European cranberry ( Vaccinium oxycoccus L.), and lingonberry ( Vaccinium vitis-idaea L.) analyzed using ultrahigh-performance liquid chromatoraphy coupled to a triple-quadrupole mass spectrometer with electrospray interface (UHPLC-MS(2)). Concentrations of A-type trimers, procyanidin A2, catechin, epicatechin, and B-type dimers and trimers have been evaluated and compared for the first time in the three berries. The data clearly show remarkable differences in the procyanidin profiles and concentrations, especially the lack of A-type trimers in V. oxycoccus; thus, the effectiveness against UTI may vary among the Vaccinium species. These differences can be used to prove authenticity.