No abstract

The productivity parameters of 2 Pleurotus spp. cultivated with two mixtures of wheat straw (WS) and peat moss (MG) were evaluated, the chemical composition of the mushrooms and also the antioxidant, antibacterial activities of hexanic extracts of the fruit bodies were determined. Pleurotus strains were fructified using the mixture 1 (60% of WS + 40% of MG) obtained the highest biological efficiencies, production rates and yields. The strain of Pleurotus ostreatus (XC005) cultivated using the mixture 2 (80% WS + 20% of MG) presented fruit bodies with highest protein content being of 25.28%, and also the strain of Pleurotus djamor (XC007) fructified on the mixture 2 showed mushrooms with highest protein content being of 30.98%. The highest antioxidant effect resulted in the hexanic extract of the Pleurotus ostreatus cultivated on M2 was found using the TBARS inhibition assay (EC50 = 0.12 mg mL- 1), while the highest antioxidant activity showed the hexanic extract of the Pleurotus djamor produced on M1 was found using the TBARS inhibition assay (EC50 = 0.21 mg mL- 1). The bactericidal effect of the hexanic extracts of Pleurotus ostreatus was obtained between 21.09 to 27.90 mg mL−1, whereas the bacteriostatic activity of the hexanic extracts of Pleurotus djamor was achieved since 19.82 to 30.98 mg mL−1. The results evidenced that the Pleurotus spp. cultivated on the mixture 2 presented highest protein content and better biological properties, encouraging the production of edible fungi strains and their use in the industrial field.

Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)

Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)

The water quality of the San Camilo and Mojahuevo estuaries was monitored in the months of April (rainy season) and June (dry season) of 2016. The water of the Mojahuevo estury presented in both seasons the lowest values of turbidity between 17.20 and 33.70 UNT, biochemical oxygen demand being in a range between 14.00 and 19.00 mg/L, zinc content (0.02-0.05 mg/L) and copper content (0.07 mg/L), ammonia content (0.21-0.35 mg/L), fats and oils (0.23-0.29 mg/L), phosphates (0.39-2.34 mg/L) and nitrates (0.84-2.29 mg/L), while the water of the two estuaries San Camilo and Mojahuevo (rainy season) showed similar phenolic content (0.019 mg/L). The results showed that the Mojahuevo estuary presented the high quality of water recommended for being used in productive process like aquaculture due to the low presence of pollutants.

Colletotrichum gloeosporioides (GC003) and Rhizopus stolonifer (RS001) were cultivated in two different liquid culture media: LC1 (glucose 40 g L-1, yeast extract 3 g L-1 and tryptone peptone 2 g L-1) and LC2 (glucose 40 g L-1, yeast extract 3 g L-1 and tryptone peptone 10 g L-1) for the production of mycelial biomass and exopolysaccharides (EPS). By using the liquid culture (LC2) under pH of 4.5 presented the highest biomass content (15.73 g L-1) in the propagation of Rhizopus stolonifer. The highest production of exopolysaccharides (1.74 g L-1) was obtained by the liquid culture (LC2) under pH of 4.5 in the cultivation of Colletotrichum gloeosporioides. The results presented that the production of biomass and exopolysaccharides (EPS) is directly related with the pHs values and the strain used in the cultivation.

Since 2013, there has been an increase (>23%) in naval traffic using maritime routes and ports on the coastal fringe of Santa Marta, Colombia. Of major concern, and described by several studies, is the relationship between maritime traffic and coastal contamination. This study proposed a maritime traffic indicator considering the simultaneous effects of several relevant measurements of water quality parameters to estimate the impact of naval activity. The approach involved developing a model including the number of vessels, hull length, and permanence time in berths. In addition, water quality variables, considering climatic seasons, were used to verify association with maritime traffic and touristic activities. The high concentrations of total coliforms (TC) and dissolved/dispersed petroleum hydrocarbons in chrysene equivalents (DDPH) reported by the International Marina of Santa Marta (SM) were affected by the local anthropic activities, including tourism, naval traffic, and urban wastewater discharges. Moreover, our results suggest the occurrence of multiple chemical impacts within Tayrona National Natural Park (PNNT) affecting conservation goals. The estimation of the maritime traffic indicator proposed in this study may be an easy and more complete tool for future studies evaluating the impact of naval activities on environmental quality.