• Antibacterial activity of Bixa orellana L. (achiote) against Streptococcus mutans and Streptococcus sanguinis

      Medina Flores, Dyanne Adenea; Ulloa Urizar, Gabriela; Camere Colarossi, Rosella; Caballero García, Stefany; Mayta Tovalino, Frank; Del Valle Mendoza, Juana; jdelvall@upc.edu.pe (2016-03)
      Objective To evaluate the cytotoxic and antibacterial effect of Bixa orellana L. (B. orellana) (achiote) methanol extract against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods Two methanol extracts of B. orellana were prepared in vitro, from the seeds and leaves. The antibacterial activity of extracts against S. mutans and S. sanguinis was evaluated using the cup-plate agar diffusion method. The minimum inhibitory concentration (MIC) was determined using the microdilution method and the cytotoxic activity was determinated by using the cell line MDCK. Results A stronger antibacterial effect was observed with the leaves methanolic extract with an inhibition zone of (19.97 ± 1.31) mm against S. mutans and (19.97 ± 1.26) mm against S. sanguinis. The methanolic extract of the seeds had an activity of (15.11 ± 1.03) mm and (16.15 ± 2.15) mm against S. mutans and S. sanguinis, respectively. The MIC of the leaf and the seed extracts against S. sanguinis was 62.5 and 125 μg/mL, respectively, and the MIC of the leaf extract against S. mutans was 62.5 μg/mL, and for the seed extract it was 31.25 μg/mL. The 50% cytotoxic concentration was 366.45 and 325.05 μg/mL for the leaves and seeds extracts, respectively. Conclusions The experimental findings demonstrated the antibacterial effect of the methanolic extract of B. orellana (achiote) on S. mutans and S. sanguinis. The extract of this plant is cytotoxic at high concentrations.
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    • Antibacterial activity of five Peruvian medicinal plants against Pseudomonas aeruginosa

      Ulloa Urizar, Gabriela; De Lama Odría, María del Carmen; Camarena Lizarzaburu, José; Del Valle Mendoza, Juana; Aguilar-Luis, Miguel Angel (Elsevier B.V., 2015-09-07)
      Objective: To evaluate the susceptibility of Pseudomonas aeruginosa (P. aeruginosa) in vitro to the ethanolic extracts obtained from five different Peruvian medicinal plants. Methods: The plants were chopped and soaked in absolute ethanol (1:2, w/v). The antibacterial activity of compounds against P. aeruginosa was evaluated using the cupplate agar diffusion method. Results: The extracts from Maytenus macrocarpa (“Chuchuhuasi”), Dracontium loretense Krause (“Jergon Sacha”), Tabebuia impetiginosa (“Tahuari”), Eucalyptus camaldulensis Dehn (eucalyptus), Uncaria tomentosa (“Uña de gato”) exhibited favorable antibacterial activity against P. aeruginosa. The inhibitory effect of the extracts on the strains of P. aeruginosa tested demonstrated that Tabebuia impetiginosa and Maytenus macrocarpa possess higher antibacterial activity. Conclusions: The results of the present study scientifically validate the inhibitory capacity of the five medicinal plants attributed by their common use in folk medicine and contribute towards the development of new treatment options based on natural products.
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    • Antibacterial activity of Myrciaria dubia (Camu camu) against Streptococcus mutans and Streptococcus sanguinis

      Camere Colarossi, Rosella; Ulloa Urizar, Gabriela; Medina Flores, Dyanne; Caballero García, Stefany; Mayta Tovalino, Frank; Del Valle Mendoza, Juana Mercedes; jdelvall@upc.edu.pe (Elsevier B.V., 2016-09)
      Objective: To evaluate the antibacterial and cytotoxic effect of Myrciaria dubia (Camu camu) (M. dubia) methanol extract, against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods: Two methanol extracts of M. dubia were prepared in vitro, from the seeds and pulp. Ten independent tests were prepared for each type of extract, using 0.12% chlorhexidine solution as positive control. Agar diffusion test was used by preparing wells with the experimental solutions cultivated in anaerobic conditions for 48 h at 37 °C. Meanwhile, the minimum inhibitory concentration and the cytotoxic effect over MDCK cell line was found. Results: A higher antibacterial effect was observed with the methanol seed extract with an inhibitory halo of (21.36 ± 6.35) mm and (19.21 ± 5.18) mm against S. mutans and S. sanguinis, respectively. The methanol extract of the pulp had an effect of (16.20 ± 2.08) mm and (19.34 ± 2.90) mm, respectively. The minimum inhibitory concentration of the pulp extract was 62.5 µg/mL for both strains, whereas for the seed antibacterial activity was observed even at low concentrations. The CC50 of the seeds extract was at a higher concentration than 800 µg/mL and 524.37 µg/mL for the pulp extract.
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    • Arboviruses emerging in Peru: need for early detection of febrile syndrome during El Niño episodes

      Tantaléan Yépez, Derek; Sánchez-Carbonel, José; Ulloa Urizar, Gabriela; Espinoza Morales, Diego; Silva-Caso, Wilmer; Pons, Maria J; Del Valle Mendoza, Juana; Aguilar-Luis, Miguel Angel; derek.2007.upc@gmail.com (Elsevier B.V., 2016-07)
      The presence of El Niño Southern Oscillation (ENSO) implies the presence of fluctuating rains in coastal areas and these changes influence the occurrence of febrile syndromes outbreaks. In Peru, Aedes aegypti is the vector responsible for various viruses such as the dengue, Zika, chikungunya, which is distributed in 18 Peruvian departments. These viruses cause similar clinical characteristics in the host and for this reason rapid, sensitive and specific diagnostic tests are needed so that the patient can receive timely treatment.
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