Efeito crioprotetor de lactose e glicose em células fúngicas imobilizadas em alginato de sódio como método de preservação de culturas

Abstract

Cryopreservation is the method of choice in many banks of microorganisms because it leads to a situation of metabolic dormancy and consequently cultures are stable for long periods. By reducing the temperature may however be formed of ice crystals which tend to cause cell damage to cell damage in turn can be avoided by vitrification process which takes place by combining a solution with the quick freezing the literature reports the use of carbohydrates vitrificadores cryoprotectants agents and also advises that the technique of immobilization of cells in sodium alginate allows the fractionation of culture and promotes the preservation of microorganisms The objective of this study is to assess the viability of the fungi of the genus Malassezia spp and the Zygomycetes group of assets in sodium alginate and lactose using glucose as cryoprotectants Twelve strains of species of Malassezia spp (9 M furfur 1 M 2 M globosa simpodialis) and twelve strains of zygomycetes (seven Mucor Rhizopus sp is 5) belonging to the mycology collection of the Specialized Center for Medical Mycology Federal University of Ceará The genus Malassezia comprises yeasts lipodependent associated with various dermatologic diseases currently comprise 13 Zygomycetes species, in turn, are ubiquitous and saprophytic fungi whose hyphae because they have high protein content and reduced size are more vulnerable to mechanical damage this way are groups of fungi in stock so hard to preserve a methodology to maintain the viability of Malassezia spp and Zygomycetes could also be used effectively for the storage of other fungi fungal structures were removed and transferred to two stock solutions, formed by 3% broth Sabouraud 15% sodium alginate and different concentrations of glucose and 9% lactose and 23% were then added plastic spheres, measuring 07cm in diameter and 0.5 cm center hole length After ionic gelation with calcium chloride Each strain was stored at -20 ° C and -80 ° C cryogenic distributed in five tubes containing 15 mL each of five levels being evaluated in five periods after nine months it was found that there was no recovery of any strain of Malassezia spp Regarding Zygomycetes species showed that after nine months of inventory four strains were viable at -80 ° C using glucose 9%, six strains were preserved at -80 ° C, using 23% glucose last six seven specimens were recovered at -80 º C using a 9% lactose and 23% respectively. Thus, the use of cryoprotectants such as carbohydrates in conjunction with the technique of immobilization of cells in sodium alginate is an alternative to maintaining some fungal species