SARS-CoV-2 in river water: Implications in low sanitation countries

Since the beginning of COVID-19 pandemic studies on viral shedding have reported that this virus is excreted in feces in most patients. High viral loads are found at the sewage pipeline or at the entrance of wastewater treatment plants from cities where the number of COVID-19 cases are significant. In Quito (Ecuador) as in many other cities worldwide, wastewater is directly discharged into natural waters. The aim of this study was to evaluate SARS-CoV-2 presence in urban streams from a low sanitation context. Three river locations along the urban rivers of Quito were sampled on the 5th of June during a peak of COVID-19 cases. River samples were evaluated for water quality parameters and afterwards, concentrated for viral analysis using skimmed milk flocculation method. The viral concentrates were quantified for SARS-CoV-2 (N1 and N2 target regions) and Human Adenovirus as a human viral indicator. The results showed that SARS-CoV-2 was detected for both target regions in all samples analyzed in a range of 2,91E+05 to 3,19E+06 GC/L for N1 and from 2,07E+05 to 2,22E+06 GC/L for N2. The high values detected in natural waters from a low sanitation region have several implications in health and ecology that should be further assessed.Universidad de Las Américas (Ecuador)Fideicomiso Sumar Juntos del Banco del PichinchaDepto. de Genética, Fisiología y MicrobiologíaFac. de Ciencias BiológicasTRUEpu

Honey quality parameters, chemical composition and antimicrobial activity in twelve Ecuadorian stingless bees (Apidae: Apinae: Meliponini) tested against multiresistant human pathogens

[EN] Ecuadorian honey samples of eight genera and 12 stingless bee species from three geographic regions (Andes, Amazon and Pacific) were studied for their physicochemical parameters, chemical composition, mineral elements and antimicrobial activity. Meliponine honey is acidic and has a high water content, but our study revealed substantial chemical variation. Oxytrigona mellaria was highest in proteins, while Melipona sp. had the most free amino acid content. Five species of honey contained vitamin C, which was highest in O. mellaria. The most abundant minerals were the macronutrients, potassium and calcium. All honey inhibited microbial growth in gram-negative and gram-positive multiresistant human pathogens, with O. mellaria and Trigona silvestriana being most effective against both bacteria

Effect of thermal liquefaction on quality, chemical composition and antibiofilm activity against multiresistant human pathogens of crystallized eucalyptus honey

Thermal liquefaction is a conventional method used by beekeepers to liquefy crystallized honey. However, an abusive use of heat may affect its quality, chemical composition and bioactivity. The purpose of this study was to investigate the effect of thermal liquefaction on the quality, chemical composition and antibiofilm properties of eucalyptus honey. Thermal liquefaction (at 45 and 60 ◦C) did not affect the honey’s quality; however, a significant reduction in the reducing capacity, total phenolic content and hydrogen peroxide content was observed. At 60 ◦C, a significant reduction in the honey’s ability to inhibit biofilm formation was observed in Pseudomonas aeruginosa, as well as a reduction in its ability to remove preformed biofilms in both Staphylococcus aureus and Pseudomonas aeruginosa. Structural changes in biofilm architecture caused by honey were not affected by thermal treatment. Therefore, we recommend liquefaction at 45 ◦C as the most convenient for honey liquefaction without affecting its characteristics