Combination Studies of Eucalyptus torelliana F. Muell. Leaf Extracts and Clarithromycin on Helicobacter pylori

Antiviral, antifungal, and insecticidal activities of Eucalyptus bark extract: HPLC analysis of polyphenolic compounds

In this study, the antiviral, antifungal, and insecticidal and HPLC analysis of polyphenolic compounds of Eucaluptus camaldulensis Dehnh. bark extract (ECBE) were evaluated. Three fungi, namely Fusarium culmorum MN398395, Rhizoctonia solani MN398397, and Botrytis cinerea MN398399 were used to colonize wood blocks of chinaberry that was previously treated with different concentrations of ECBE at 1%, 2%, and 3%. Antiviral evaluations (protective, curative, and inactivating activities) of the extract at 100 μg/mL were assayed against Tobacco mosaic virus (TMV) MG264131 using the half-leaf method to determine the inhibitory percentage towards the number of local lesions. The protective treatment of Nicotiana glutinosa leaves exhibited excellent activity (72.22%) with a 91.1-fold reduction in TMV-CP accumulation in infected tissues. Furthermore, Real-time quantitative PCR revealed that the expression level of PAL and PR-1 (salicylic acid marker) genes were significantly up regulated at four days-post inoculation (dpi) for all treatments compared to untreated leaves. The insecticidal effect was screened by the contact and fumigant methods against Tribolium castaneum (Herbst) and Sitophilus oryzae L. in vitro. In contact assay, all concentrations 1, 5, 10, 20 and 30 ppm caused 100% toxicity to the two tested pests within 24 h, whereas the fumigant assay, gave the highest mortality against T. castaneum and S. oryzae by 20 ppm (61.66%) and 30 ppm (57.77%), respectively after 24 h. The HPLC analysis of ECBE revealed that benzoic acid, quinol, salicylic acid, myricetin, and rutin were the most abundant polyphenolic compounds found in the extract. In conclusion, when the extract concentration increases, the growth of fungal mycelia was decreased compared with the control, especially against F. culmorum. According to the hypotheses of the results, the ECBE recommended to prevent the wood from discoloration, fungal molds by acting as bio-preservative, also trigger the resistance of plants against viral infection and high toxicity against stored-product insects.

In vitro activity of Aloe vera inner gel against Helicobacter pylori strains

Aloe barbadensis Miller (Aloe vera) is a herbal remedy widely used for a variety of illnesses; A. vera leaf extracts have been promoted for detoxification, cure constipation, help flush out toxins and wastes from the body, promote digestion and are used in the treatment of peptic ulcer for cytoprotective action. The aim of this study was to evaluate the antibacterial activity of A. vera inner gel against both susceptible and resistant Helicobacter pylori strains isolated in Abruzzo region, Italy. The inner gel of leaves of a 5-year-old plant of A. vera was extracted, homogenized and tested from 800 to 1.56 mg ml(-1) against 14 clinical strains and one reference strain of H. pylori using the broth microdilution methodology. Furthermore, the sample of A. vera was investigated for the chemical fingerprint of anthraquinones. The inhibitory concentrations of A. vera inner gel were similar to the bactericidal ones, with values ranging from 6.25 to 800 mg ml(-1) . Fifty per cent of the detected strains, independently of their susceptibility profile, were inhibited in their growth at 100 mg ml(-1) . Aloe vera inner gel expresses antibacterial properties against H. pylori and, therefore, in combination with antibiotics, could represent a novel strategy for the treatment of the infection of H. pylori, especially in cases of multiresistance.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study demonstrates that the Aloe vera inner gel expresses antibacterial properties against both susceptible and resistant Helicobacter pylori strains. These findings may impact on the antimicrobial resistance phenomenon of H. pylori, proposing the A. vera inner gel as a novel effective natural agent for combination with antibiotics for the treatment of H. pylori gastric infection.

Potentiating therapeutic effects by enhancing synergism based on active constituents from traditional medicine

Shifting current drug discovery tide from 'finding new drugs' to 'screening natural products' may be helpful for overcoming the 'more investment, fewer drugs' challenge. Traditional Chinese medicine (TCM), relying on natural products, has been playing a very important role in health protection and disease control for thousands of years in Asia, whose therapeutic efficacy is based on the 'synergism', that is, the combinational effects to be greater than that of the individual drug. Based on syndromes and patient characteristics and guided by the theories of TCM, formulae are designed to contain a combination of various kinds of crude drugs that, when combined, generally assume that a synergism of all ingredients will bring about the maximum of therapeutic efficacy. The increasing evidence has shown that multiple active component combinations of TCM could amplify the therapeutic efficacy of each agent, representing a new trend for modern medicine. However, the precise mechanism of synergistic action remains poorly understood. The present review highlights the concept of synergy and gives some examples of synergistic effects of TCM, and provides an overview of the recent and potential developments of advancing drug discovery towards more agile development of targeted combination therapies from TCM.

The Effects of Two Novel Copper-Based Formulations on Helicobacter pylori

We investigated the effects of two novel copper-based inorganic formulations for their activity against 60 isolates of Helicobacter pylori (Hp). The two copper-based formulations were tested against three NCTC Helicobacter pylori isolates and 57 clinical strains isolated from the UK and Italy in time-kill assays. Both copper-based formulations were bio-cidal against all Helicobacter pylori strains tested reducing the viable count by 4-5 log within 2 h. These two copper-based anti-microbial agents deserve further study in relation to the treatment of H. pylori-related gastric disease.