Cytotoxicity and Biological Activities of Geopopolis Extract from the Stingless bee (Melipona scutellaris) in Isolates of Staphylococcus aureus.

Geopropolis resins are produced by stingless bees (Meliponinae), developed from the collection of resinous materials, waxes and exudates, from the flora of the region where stingless bees are present, in addition to the addition of clay or earth in its composition. Several biological activities are attributed to Ethanol Extracts of Geopropolis (EEGP). The bioactive properties are associated with the complex chemical composition that the samples have. This work aims to evaluate the biological activities of the EEGP, in order to contribute with a natural therapeutic alternative, to face infections, mainly those caused by resistant strains of Staphylococcus aureus. The EEGP MIC tests showed antibacterial activity against two strains of S. aureus, both at concentrations of 550 µg/mL. The MBC performed with the inhibition values showed that the EEGP has bacteriostatic activity in both strains. Biofilm inhibition rates exhibited an average value greater than 65 % at the highest concentration. The EEGP antioxidant potential test showed good antioxidant activity (IC50) of 11.05±1.55 µg/mL. In the cytotoxicity test against HaCat cells, after 24 hours, EEGP induced cell viability at the three tested concentrations (550 µg/mL: 81.68±3.79 %; 1100 µg/mL: 67.10±3.76 %; 2200 µg/mL: 67.40±1.86 %). In view of the above, the safe use of EEGP from the brazilian northeast could be proven by the cytotoxicity test, and its use as an antioxidant and antibacterial agent has proven to be effective, as an alternative in combating oxidative stress and microorganisms such as S. aureus, which, through the spread and ongoing evolution of drug resistance, generates an active search for effective solutions.

Novel Therapeutic Options for Chagas Disease Based on Bioactive Compounds from Algae, Bacteria and Fungi Species.

Chagas Disease, also known as American trypanosomiasis, is a Neglected Tropical Disease that affects around seven million people, especially in Latin America. Noteworthy, there has been an increase in the numbers of case reports in non-endemic areas, such as North America, Europe, Japan, and Australia. The disease is a vector-borne disease caused by the pathogen Trypanosoma cruzi being transmitted by infected bugs. It is known that about forty percent of infected patients develop cardiac, digestive, or neurological alterations. There are only two drugs currently used for treatment, benznidazole and nifurtimox. However, both therapeutic regimens present several limitations, such as toxicity, mutagenicity and low efficiency during the chronic phase. Some reports in the literature point to the occurrence of parasite resistance. To overcome these limitations, the bioprospection of novel molecules as alternatives is one of the major goals to improve therapeutic success in this chronic disease. Bioprospecting active metabolites from natural resources might bring new hopes for disease control and parasite elimination. Here we summarize the most recent advances to identify and test Algae, Bacteria and Fungi-derived bioactive compounds with trypanocidal activity using experimental models, in vitro testing and in silico approaches.