The contribution of phenolic acids to the anti-inflammatory activity of mushrooms: Screening in phenolic extracts, individual parent molecules and synthesized glucuronated and methylated derivatives

In the present study, the ethanolic extracts of fourteen edible mushrooms were investigated for their anti-inflammatory potential in LPS (lipopolysaccharide) activated RAW 264.7 macrophages. Furthermore the extracts were chemically characterized in terms of phenolic acids and related compounds. The identified molecules (p-hydroxybenzoic, p-coumaric and cinnamic acids) and their glucuronated and methylated derivatives obtained by chemical synthesis were also evaluated for the same bioactivity, in order to establish structure-activity relationships and to comprehend the effects of in vivo metabolism reactions in the activity of the compounds. The extracts of Pleurotus ostreatus, Macrolepiota procera, Boletus impolitus and Agaricus bisporus revealed the strongest anti-inflammatory potential (EC50 values 96 ± 1 to 190 ± 6 µg/mL, and also the highest concentration of cinnamic acid (656 to 156 µg/g), which was also the individual compound with the highest anti-inflammatory activity. The derivatives of p-coumaric acid revealed the strongest properties, specially the derivative methylated in the carboxylic group (CoA-M1) that exhibited similar activity to the one showed by dexamethaxone used as anti-inflammatory standard; by contrast, the derivatives of p-hydroxybenzoic revealed the lowest inhibition of NO production. All in all, whereas the conjugation reactions change the chemical structure of phenolic acids and may increase or decrease their activity, the glucuronated and methylated derivatives of the studied compounds are still displaying anti-inflammatory activity.

In vitro anti-Candida activity of Glycyrrhiza glabra L.

The severity and frequency of opportunistic fungal infections still growing, concomitantly to the increasing rates of antimicrobial drugs resistance. Natural matrices have been used over years due to its multitude of health benefits, including antifungal potential. Thus, the present work aims to evaluate the anti-Candida potential of the phenolic extract and individual phenolic compounds of Glycyrrhiza glabra L. (licorice), by disc diffusion assay, followed by determination of the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for both planktonic cells and biofilms. Licorice extract evidenced inhibitory potential against the nineteen tested Candida strains, but no pronounced effect was observed by testing the most abundant individual phenolic compounds. Candida tropicalis strains were the most sensible, followed by Candida glabrata, Candida parapsilosis and, then, Candida albicans. Lower MIC and MFC values were achieved to C. glabrata and C. tropicalis, which confirms its susceptibility to licorice extract; however, for C. tropicalis strains a higher variability was observed. Anti-biofilm potential was also achieved, being most evident in some C. glabrata and C. tropicalis strains. In general, a twice concentration of the MIC was necessary for planktonic cells to obtain a similar potential to that one observed for biofilms. Thus, an upcoming approach for new antifungal agents, more effective and safer than the current ones, is stablished; notwithstanding, further studies are necessary in order to understand its mechanism of action, as also to assess kinetic parameters.

Impact of an educational hands-on project on the antimicrobial, antitumor and anti-inflammatory properties of plants on Portuguese students' awareness, knowledge, and competences

Promoting environmental and health education is crucial to allow students to make conscious decisions based on scientific criteria. The study is based on the outcomes of an Educational Project implemented with Portuguese students and consisted of several activities, exploring pre-existent Scientific Gardens at the School, aiming to investigate the antibacterial, antitumor and anti-inflammatory properties of plant extracts, with posterior incorporation in soaps and creams. A logo and a webpage were also created. The effectiveness of the project was assessed via the application of a questionnaire (pre- and post-test) and observations of the participants in terms of engagement and interaction with all individuals involved in the project. This project increased the knowledge about autochthonous plants and the potential medical properties of the corresponding plant extracts and increased the awareness about the correct design of scientific experiments and the importance of the use of experimental models of disease. The students regarded their experiences as exciting and valuable and believed that the project helped to improve their understanding and increase their interest in these subjects and in science in general. This study emphasizes the importance of raising students’ awareness on the valorization of autochthonous plants and exploitation of their medicinal properties.

Anti-inflammatory and antinociceptive activities of Bauhinia monandra leaf lectin

A galactose-specific lectin from Bauhinia monandra leaves (BmoLL) have been purified through ammonium sulphate fractionation followed by guar gel affinity chromatography column. This study aimed to evaluate the potential anti-inflammatory and antinociceptive activity of pure BmoLL in mice. Anti-inflammatory activity was evaluated by 1% carrageenan-induced inflammation in mice treated with BmoLL. Acetic acid-induced abdominal writhing and hot plate methods evaluated antinociceptive activity. BmoLL significantly inhibited the carrageenan-induced paw edema by 47% (30 mg/kg) and 60.5% (60 mg/kg); acetylsalicylic acid (ASA, 100 mg/kg) showed inhibition of 70.5%, in comparison to controls. Leukocyte migration, an immune response to the inflammation process, was significantly reduced in presence of BmoLL; in mice treated with \ASA\ the decrease in leukocyte migration was similar to 15 mg/kg of the lectin. BmoLL at doses of 15, 30 and 60 mg/kg significantly reduced the number of animal contortions by 43.1, 50.1 and 71.3%, respectively.BmoLL leukocyte migration was significantly reduced; in mice treated with \ASA\ the decrease in leukocyte migration was similar to 15 mg/kg of the lectin. BmoLL at doses of 15, 30 and 60 mg/kg significantly reduced the number of animal contortions by 43.1, 50.1 and 71.3%, respectively. The lectin (30 and 60 mg/kg) showed a significant effect in the hot plate assay. BmoLL anti-inflammatory and antinociceptive effects were dose-dependent. The search for new and natural compounds, with minimal side effects, to control pain and inflammation, is constantly increasing. BmoLL has great potential as a natural anti-inflamatory product that can be explored for pharmacological purposes.

Synthesis and anticancer activity of N3-substituted-6,8-diaminopurines

[Excerpt] Cancer is the second most common cause of death in developed countries appearing just after cardiovascular diseases. The treatment of cancer remains a major medical challenge and the development of new anticancer drugs is an emerging topic for the scientific community. During the past three decades several chemical classes of anticancer drugs have been identified. In particular, 2,6-diamino purines proved to be important candidates as new anti-cancer agents.

In vivo antioxidant activity of phenolic compounds: facts and gaps

Background: Numerous diseases have been related with free radicals overproduction and oxidative stress. Botanical preparations possess a multitude of bioactive properties, including antioxidant potential, which has been mainly related with the presence of phenolic compounds. However, the mechanisms of action of these phytochemicals, in vivo effects, bioavailability and bio-efficacy still need research. Scope and Approach: The present report aims to provide a critical review on the aspects related with the in vivo antioxidant activity of phenolic extracts and compounds from plant origin. Key findings: Biological functions beyond the human metabolism were discussed, comparing in vivo vs. in vitro studies, as also focusing the conditioning factors for phenolic compounds bioavailability and bio-efficacy. Furthermore, an upcoming perspective about the use of phytochemicals as life expectancy promoters and anti-aging factors in human individuals was provided. Conclusions: Overall, and despite all of those advances, the study of the biological potential of numerous natural matrices still remains a hot topic among the scientific community. In fact, the available knowledge about the responsible phytochemicals for the biological potential, their mechanisms of action, the establishment of therapeutic and prophylactic doses, and even the occurrence of biochemical inter-relations, is considerable scarce.