Resumen Introducción y objetivos : Los documentos en papel custodiados en bibliotecas pueden mostrar signos de deterioro causados por la actividad de diferentes hongos. Los principales colorantes fúngico que deterioran estéticamente este sustrato y afectan al patrimonio cultural en soporte celulósico constituyen los pigmentos oscuros o melaninas. El objetivo del presente trabajo es brindar un panorama actualizado del estado de arte de los hongos negros que colonizan papel y las melaninas que sintetizan. M&M : Se realizó una búsqueda bibliográfica sobre los pigmentos oscuros que sintetizan diferentes hongos negros que deterioran papel. Se analizaron 74 trabajos especializados en el tema. Resultados : El conocimiento sobre la diversidad y las características de los pigmentos oscuros que son sintetizados por los hongos negros que deterioran papel es clave para desarrollar estrategias de prevención y remediación para eliminar estos pigmentos de soportes celulósicos con valor patrimonial. Este trabajo presenta información sobre: hongos negros que deterioran papel, tipos de melaninas que pueden sintetizar, estructuras donde se acumulan, y su contribución en el deterioro estético. Conclusiones : Este conocimiento sirve de base para desarrollar nuevas estrategias de restauración que pudieran ser efectivas y sustentables y que aseguren la conservación preventiva de documentos históricos y obras de arte en papel.

Summary Background and aims : Paper documents stored in librarles may show signs of deterioration caused by the activity of different fungi. The main fungal dyes that aesthetically deteriórate this substrate and affect the cultural heritage on cellulosic support are dark pigments or melanins. The aim of this work is to provide an updated overview of the state of the art of black fungi that colonize paper and the melanins that they synthesize. M&M : A bibliographic search was carried out on the dark pigments that synthesize different black fungi that deteriorate paper. 74 specialized papers on the subject were analyzed. Results : Knowledge about the diversity and characteristics of the dark pigments that are synthesized by the black fungi that deteriorate paper is key to developing prevention and remediation strategies to eliminate these pigments from cellulosic supports with heritage value. This work presents information on: black fungi that deteriorate paper, types of melanins that can be synthesized, structures where they accumulate, and their contribution to aesthetic deterioration. Conclusions : This knowledge serves as the basis for developing new restoration strategies that could be effective and sustainable and that ensure the preventive conservation of historical documents and works of art on paper.

Abstract Grape pomace from Vitis labrusca is an important sub-product of the “American table wine” industry. It is recalcitrant to degradation, and its accumulation is a serious problem with negative environmental impacts. We analyzed the ability of five white-rot fungi to transform this residue in-vitro. Mass loss and phenol removal in grape pomace treated with each fungus were compared after 30-day solid-state fermentation. Since Peniophora albobadia isolate LPSC 285 was the fungus that showed the highest degradative ability and the lowest free phenol levels in the residue transformed, we selected this fungus to monitor its effect on this residue after 30, 60, and 90 days of incubation. We analyzed mass loss of the residue caused by the fungus activity and its chemical changes using Fourier transform infrared spectroscopy. After 90 days of incubation, Peniophora albobadia isolate LPSC 285 reduced grape pomace mass by 20.48%, which was associated with degradation of polysaccharides and aromatic structures. We concluded that Peniophora albobadia LPSC # 285 isolate is a promising fungus to transform grape pomace from Vitis labrusca under solid-state fermentation conditions.

Minimidochium parvum LPSC # 548, a fungus isolated from litter floating on waters of Río Santiago (Provincia de Buenos Aires, Argentina) polluted with industrial effluents and crude-oil, was grown as a shaking culture on a C-limited medium to evaluate its ability to produce extracellular laccase. The effect of anthracene, CuSO4 · 5H2O, ethanol, guaiacol, humic acids, Kraft lignin, MnSO4· H2O, Tween 20 and veratryl alcohol on its growth and extracellular laccase activity levels was also analyzed. The cultures grown on basal medium produced maximum biomass (over 420 mg/100 ml) and maximum extracellular laccase activity (351.7 ±53.3 pkat/ml) after 5 days of incubation. Among the different factors tested, only the humic acids at 0.1 % (w/v) were found to stimulate the growth of M. parvum . However, Tween 20 (0.1 %, v/v) was the only one that produced an increase of laccase activity levels up to 2.5-fold compared to the control.

Minimidochium parvum LPSC # 548, un hongo aislado de materia orgánica colectada en aguas de Río Santiago (Provincia de Buenos Aires, Argentina) contaminadas con efluentes industriales y crudo de petróleo, se cultivó en un medio líquido limitante en carbono bajo agitación para evaluar su habilidad para producir lacasa extracelular. Se analizó también el efecto de ácidos húmicos, alcohol veratrílico, antraceno, CuSO4 · 5H2O, etanol, guaiacol, lignina Kraft, MnSO4· H2O y Tween 20 sobre el crecimiento fúngico y los niveles de actividad lacasa extracelular. Los cultivos sobre medio basal produjeron máximos niveles de biomasa (superior a 420 mg/100 ml) y actividad lacasa extracelular (351,7 ±53,3 pkat/ml) después de 5 días de incubación. Entre los diferentes agentes químicos testeados, sólo los ácidos húmicos al 0,1 % (p/v) estimularon el crecimiento de M. parvum . No obstante, sólo el Tween 20 (0,1 %, v/v) produjo un incremento de los niveles de actividad lacasa (2,5 veces comparado a cultivos control).

The ability of Dictyosporium triramosum, Minimidochium parvum and Tetraploa aristata, isolated from organic matter collected in Río Santiago (Buenos Aires Province, Argentina), to grow and decolorize agar media supplemented with different synthetic chromophores at 0.01% (w v-1) was analyzed. Crystal violet and brilliant green reduced the growth of the three strains showing the highest inhibition percentages. While eosin and rose bengal did not affect D. triramosum, growth inhibition values superior to 50 % were observed for M. parvum and T. aristata. Congo red and neutral red inhibited growth of both D. triramosum and M. parvum in a 12-17%, but those dyes did not reduced T. aristata growth. D. triramosum and T. aristata were not affected by the toluidine blue dye, while M. parvum was inhibited by that chromophore. Methyl red only inhibited to M. parvum and T. aristata. The 3 strains tested revealed ability to decolorize the medium supplemented with methyl red and toluidine blue. D. triramosum decolorized also the medium with congo red and crystal violet, and T. aristata produced also the decolorization of the agar medium with crystal violet and neutral red. None of the fungi studied decolorized the media with brilliant green, eosin and rose bengal.

Se analizó la capacidad de Dictyosporium triramosum, Minimidochium parvum y Tetraploa aristata, aisladas de materia orgánica colectada en Río Santiago (Provincia de Buenos Aires, Argentina), para crecer y decolorar medios agarizados y suplementados con diferentes cromóforos sintéticos al 0,01 % (p v-1). Cristal violeta y verde brillante redujeron el crecimiento de las 3 cepas revelando los mayores porcentajes de inhibición. Mientras que eosina y rosa de bengala no afectaron a D. triramosum, valores superiores al 50 % de inhibición se observaron en M. parvum y T. aristata. Rojo congo y rojo neutral redujeron a D. triramosum y M. parvum en un 12-17 %, pero no a T. aristata. D. triramosum y T. aristata no resultaron afectados por azul de toluidina, mientras M. parvum fue inhibido por el colorante. Rojo de metilo sólo inhibió a M. parvum y T. aristata. Las 3 cepas probadas revelaron capacidad para decolorar el medio suplementado con azul de toluidina y rojo de metilo. D. triramosum decoloró además el medio suplementado con cristal violeta y rojo congo, y T. aristata el medio con cristal violeta y rojo neutral. Ninguno de los hongos estudiados decoloró los medios con eosina, rosa de bengala y verde brillante.