Growth and exoenzyme production by Trametes trogii and Trametes versicolor var. antarcticus on wet olive cake (“alperujo” in spanish)

KAEN RM; DIORIO LA; LEVIN LN; SALVATIERRA D

Córdoba

Congreso; VI Congreso Argentino de Microbiología General; 2009

Sociedad Argentina de Microbiología General

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} p.Default, li.Default, div.Default {mso-style-name:Default; mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:none; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; color:black;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:841.9pt 595.3pt; mso-page-orientation:landscape; margin:3.0cm 70.9pt 3.0cm 70.9pt; mso-header-margin:35.45pt; mso-footer-margin:35.45pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Wet olive cake, a by-product from olive-oil extraction is generated in huge amounts in areas were olive is cultivated. It exhibits phytotoxic properties, due to its high content of polyphenols. An interest application of this waste is its use in agriculture as organic amendment. To this purpose its phenols must be degraded. In the study we evaluated growth and exoenzyme production by two white rot fungi: Trametes trogii and Trametes versicolor var. antarcticus on wet olive cake, under different treatments, in views of applying them to phenol degradation. Olive cake was subject to different treatments before inoculation, to reduce its fatty acids content that may interfere with fungal growth. It was saturated either with water or with HCl 1, 3 or 5N and left for 24 hs or autoclaved. Then the samples were repeatedly washed, rehydrated to 60% water content and autoclaved. Non-treated olive cake was used as control. Samples were collected after 14 days, and sugar content and exoenzyme fungal production was measured. Polymethylgalacturonase, polygalacturonase, laccase, Mn-peroxidase, endoglucanase and endoxylanase activities were determined. Treatment with HCl inhibited the growth of both fungi. Highest lacase and Mn-peroxidase activities were produced by T. trogii, after treating olive waste with water, leaving it in rest for 24 hs. T. trogii produced higher titers of cellulolytic and xylanolytic enzymes and lower levels of pectinases, when applying this treatment to the waste. Best ligninolytic titers were determined in T. versicolor when growing it on non-treated olive cake. It also produced high xylanolytic and pectinolytic activities, but lower levels of cellulases.