Imobilização de fungos filamentosos com potencial para uso agroindustrial

Abstract

Cellular immobilization represents an alternativefor the bioprocess conduction, in which the cells are kept in a matrix and can be used over long periods. The objective of this work was to test a new fungi immobilization methodology with reduced cost to evaluate the viability of these fungi when submitted to the new encapsulation method, and to determine the ideal temperature to store the immobilized fungi. The mycelium of the fungi Aspergillus niger, Cladosporium cladosporioides and Penicillium solitum were mixed with 15 g of titrated rice and 3 g of sodium alginate, which was dripped in a 0.25 M calcium chloride solution for the formation of pellets. After drying in an oven at 26ºC, the granules were stored at three temperatures: room, refrigerator and freezer. The platings were carried out every 15 days in culture medium. The evaluations of the colony size and sporulation were carried out 7, 14 and 12 days after plating, for 195 days for A. niger, 225 days for C. cladosporioides, and 210 days for P. solitum. Storage temperature did not affect the mycelial development of A. niger and P. solitum. However, sporulation was reduced for the granules stored in the freezer. The mycelial development of C. cladosporioides was influenced by temperature. The granules conserved at room temperature had lower viability than those stored in the refrigerator and freezer. In the Scanning Electronic Microscopy analysis, it was observed that the immobilization is a safe method in which the fungus mycelium remains inside the granule, facilitating transport, storage and application of micro-organisms. KEYWORDS: cellular immobilization; encapsulation of fungi; sodium alginate; granulated formulation. RESUMO:A imobilização celular representa uma alternativa para a condução de bioprocessos. As células ficam retidas em matrizes e podem ser utilizadas por longos períodos. O objetivo deste trabalho foi testar uma nova metodologia de imobilização de fungos com custo reduzido, avaliar a viabilidade e segurança dos fungos submetidos ao novo método de encapsulamento e determinar a temperatura ideal para armazenar os fungos imobilizados. Os micé-lios dos fungos Aspergillus niger, Cladosporium cladosporioides e Penicillium solitum foram misturados com 15 g de arroz triturado e 3 g de alginato de sódio, que gotejava em uma solução de cloreto de cálcio a 0,25 M para a formação dos grânulos. Após a secagem em estufa a 26ºC, os grânulos foram armazenados em temperaturas ambiente, geladeira e freezer. Os plaqueamentos foram realizados a cada 15 dias em meio de cultura. As avaliações do tamanho das colônias e esporulação foram realizadas 7, 14 e 21 dias após o plaqueamento, durante 195 dias para A. niger, 225 dias para C. cladosporioides e 210 dias para P. solitum. A temperatura de armazenamento não afetou o desenvolvimento micelial de A. niger e P. solitum. Porém, a esporulação foi reduzida para os grânulos armazenados no freezer. O desenvolvimento micelial de C. cladosporioides foi influenciado pela temperatura. Os grânulos conservados ...

Study on the transfructosylation activity of Aspergillus oryzaeIPT‐301 cells in a packed bed reactor aiming at fructooligosaccharide production

“…Figure 2 showed a homogeneous mycelium formed by non‐septate hyphae and without the presence of fruiting bodies or spores — characteristics inherent to the mycelial growth of a filamentous fungus. These results are in accordance with the classification attributed to the genus Aspergillus sp 33,34 …”

In vitro Inhibitory Action of the Essential Oils of Origanum Vulgare and Rosmarinus Officinalis against Aspergillus Fumigatus

“…All plates were kept in a glasshouse (Quimis) at a temperature of 28 ± 2 ºC, and after 36 hours, daily monitoring was carried out, checking the development or inhibition of the fungus, using positive and negative control as the growth pattern [7,47]. The evaluation of the antifungal activity of the EOs and the positive control was verified through the development of the colonies (diameter in millimeters), with the measurement of mycelium with the help of a millimeter ruler every 7 days, for 21 days, calculating the average of the diameter of the colonies to obtain the kinetics of the mycelial growth index (MGI) [47,56]. The MGI calculation was performed according to the formula presented below [56]…”

“…The evaluation of the antifungal activity of the EOs and the positive control was verified through the development of the colonies (diameter in millimeters), with the measurement of mycelium with the help of a millimeter ruler every 7 days, for 21 days, calculating the average of the diameter of the colonies to obtain the kinetics of the mycelial growth index (MGI) [47,56]. The MGI calculation was performed according to the formula presented below [56]…”

“…After 36 hours, with the help of a millimeter ruler, daily monitoring of petri dishes was carried out for 21 days, analyzing the growth or inhibition of the fungus and measuring the diameter of the halos observed around the discs, every 7 days. The EOs and the positive control that was considered to have inhibitory activity had an inhibition diameter ≥ 10 mm; and those without inhibitory activity showed an inhibition diameter < 10 mm [32,56].…”

Avaliação Microbiológica Da Alface Comercializada Em Diferentes Feiras Do Município De São Luís-Ma

“…Bayanus de Lallemand e, como fonte de nitrogênio o pólen de abelha. por ser simples, barato e não tóxico para os microrganismos, permitindo que as células realizem seus processos biológicos sem desestabilizar a esfera (ELIZEI et al, 2014).…”