Yeasts Associated with Various Amazonian Native Fruits.

Yeasts, commonly present on the surface of fruits, are of industrial interest for the production of enzymes, flavorings, and bioactive compounds, and have many other scientific uses. The Amazonian rainforest may be a good source of new species or strains of yeasts, but their presence on Amazonian fruits is unknown. The aim of this study was to identify and characterize yeasts isolated from Amazonian native fruits using molecular and phenotypic methods. In total, 81 yeast isolates were obtained from 10 fruits species. Rep-PCR showed 29 strain profiles. Using a combination of restriction-fragment length polymorphism (RFLP) of the 5.8S-ITS region and D1/D2 sequencing of the 26S rRNA gene, 16 species were identified belonging to genera Candida, Debaryomyces, Hanseniaspora, Kodamaea, Martiniozyma, and Meyerozyma. The most dominant species were Candida tropicalis, Debaryomyces hansenii, Hanseniaspora opuntiae, and Hanseniaspora thailandica. H. opuntiae and H. thailandica showed the highest number of the strain profiles. Phenotypic profiles were variable between species, and even among strains. Screening for hydrolases showed lipolytic activity in only one isolate, while proteolytic, cellulolytic and amylolytic capabilities were not detected. Yeast presence among fruits varied, with cidra (Citrus medica) and ungurahui (Oenocarpus bataua) having the highest number of species associated. This investigation broadens the understanding and possible biotechnological uses of yeast strains obtained from Amazonian native fruits.Yeasts, commonly present on the surface of fruits, are of industrial interest for the production of enzymes, flavorings, and bioactive compounds, and have many other scientific uses. The Amazonian rainforest may be a good source of new species or strains of yeasts, but their presence on Amazonian fruits is unknown. The aim of this study was to identify and characterize yeasts isolated from Amazonian native fruits using molecular and phenotypic methods. In total, 81 yeast isolates were obtained from 10 fruits species. Rep-PCR showed 29 strain profiles. Using a combination of restriction-fragment length polymorphism (RFLP) of the 5.8S-ITS region and D1/D2 sequencing of the 26S rRNA gene, 16 species were identified belonging to genera Candida, Debaryomyces, Hanseniaspora, Kodamaea, Martiniozyma, and Meyerozyma. The most dominant species were Candida tropicalis, Debaryomyces hansenii, Hanseniaspora opuntiae, and Hanseniaspora thailandica. H. opuntiae and H. thailandica showed the highest number of the strain profiles. Phenotypic profiles were variable between species, and even among strains. Screening for hydrolases showed lipolytic activity in only one isolate, while proteolytic, cellulolytic and amylolytic capabilities were not detected. Yeast presence among fruits varied, with cidra (Citrus medica) and ungurahui (Oenocarpus bataua) having the highest number of species associated. This investigation broadens the understanding and possible biotechnological uses of yeast strains obtained from Amazonian native fruits.

Caracterización de bacterias halófilas productoras de amilasas aisladas de las Salinas de San Blas en Junín / Characterization of halophilic bacteria producing amylase isolated from San Blas Salterns in Junin

El objetivo de este estudio fue caracterizar bacterias halófilas con actividad amilolítica provenientes de las Salinas de San Blas-Junín, ubicadas en los Andes peruanos aproximadamente a 4100 m de altitud. Este estudio se realizó con 34 bacterias aisladas de muestras de suelos las cuales se cultivaron en agar agua de sales (SW) 5 % conteniendo extracto de levadura 0,5 % y almidón 1 %. El 41 % de bacterias mostró la capacidad de hidrolizar almidón, éstas fueron caracterizadas mediante pruebas fisiológicas y bioquímicas convencionales. Tres bacterias fueron Gram-negativas y once Gram-positivas. El 21 % (3/14) creció en un amplio rango de concentración de sales, entre 5 y 20 %. El 14 % (2/14) de las bacterias presentó actividad lipolítica, proteolítica y nucleolítica, y el 29 % (4/14), presentó actividad proteolítica y nucleolítica. Las bacterias se identificaron mediante los perfiles de restricción de los genes ribosómicos 16S amplificados, las enzimas usadas fueron Hae III, BstU I, Hinf I y Cfo I. Los genes ribosómicos 16S de siete bacterias que presentaron perfiles de ADN diferentes se amplificaron, secuenciaron y analizaron mediante programas bioinformáticos. Del análisis fenotípico y molecular de las 14 bacterias amilolíticas se obtuvieron dos grupos, uno perteneciente al género Halomonas (3) y el otro, al género Bacillus (11). Las bacterias amilolíticas caracterizadas podrían ser de potencial uso a nivel industrial.

The aim of this study was to characterize halophilic amylolytic bacteria from San Blas Salterns-Junin, located in the Peruvian Andes at approximately 4 100 m of altitude. This study was conducted with 34 bacteria isolated from soil samples which were cultured in salt water medium (SW) 5 % containing 0,5 % yeast extract and 1 % starch. It was found that 41 % were starch-degrading bacteria, which were further characterized with conventional physiological and biochemical tests. Three bacteria were Gram-negative and eleven Gram-positive. Also, 21 % (3/14) was able to grow in a wide range of saltconcentration from 5 to 20 %. We reported that 14 % (2/14) of bacteria had all lipolytic, proteolytic and nucleolytic activity, and 29 % (4/14) had both proteolytic and nucleolytic activity. Bacteria were identified by restriction 16S ribosomal genes profiles, enzymes used were Hae III, BstU I, Hinf I and Cfo I. 16S ribosomal genes of seven isolated wich showed different DNA profiles were amplified, partial sequenced and analyzed using bioinformatic programs. By both phenotypic and molecular analysis of 14 amylolytic bacteria two groups were obtained, one belonged to the genus Halomonas (3) and the other, to the genus Bacillus (11). The characterized amylolytic bacteria could have a potential industrial use.