Efeito combinado de carvacrol e tiabendazol contra Colletotrichum gloesporioides, Fusarium solani e Alternaria alternata / Combined effect of carvacrol and thiabendazole against Colletotrichum gloesporioides, Fusarium solani and Alternaria alternata

O objetivo deste trabalho foi determinar a atividade antimicrobiana do carvacrol e sua combinação com tiabendazol no controle de fungos patogênicos deteriorantes de frutas (Colletotrichum gloesporioides, Fusarium solani e Alternaria alternata). O carvacrol apresentou uma concentração inibitória mínima (CIM) de 282 a 563 μg mL-1 para os fungos testados. Quando avaliado em conjunto com o tiabendazol apresentou efeito aditivo contra C. gloesporioides e F. solani (FICI 0,5 e 1,0, respectivamente) e sinérgico contra a A.alternata (FICI 0,1). Houve redução da CIM do carvacrol de 50 a 88%. Este estudo mostra o potencial do uso.

ß-Glucanase Addition in Brewing Malt Produced by Reduced Time of Germination

Abstract The β-Glucans content has straight influence on the quality of malt and beer, mainly during the filtration step. Barley presenting high β-Glucan content demands longer germination time at malting. The application of commercial β-Glucanase is an alternative to accelerate the process and preserve the quality of malt. This work aimed to evaluate the effect of commercial β-Glucanase addition in malt produced within reduced germination time (64 h). Micro-malting was conducted with BRS-Caue and Elis barley cultivars at germination time 64 h and 96 h. The β-Glucanase concentration applied were 0, 25, 50 and 100 mg.kg-1. Barley, malt and wort samples were analyzed to check their physical-chemical features. Beers were produced with BRS-Caue malt and the physical-chemical and sensory attributes were analyzed. The commercial enzyme addition in BRS-Caue and Elis (64 h), at concentration 25 and 50 mg.kg-1, resulted in wort presenting proper β-Glucan content (≤ 178 mg.L-1). The beer produced with malt germinated for 64 h and added with 50 mg.kg-1 of β-glucanase was the one showing the largest number of physical-chemical and sensory parameters similar to the beer made with malt germinated for 96 h (conventional process). Commercial β-glucanase application in malt allowed accelerating the malting process without affecting the quality of the malt for beer production.

Degradation of lignosulfonic and tannic acids by ligninolytic soil fungi cultivated under icroaerobic conditions

Soil fungi were evaluated regarding their ability to degrade lignin-related compounds by producing the ligninolytic enzymes. Lignosulfonic and tannic acids were used as sole carbon sources during 30 days under microaerobic and very-low-oxygen conditions. The fungi produced lignin-peroxidase, manganese-peroxidase and laccase . Expressive degradations was observed by C18 reversed-phase HPLC, indicating the biodegradation potential of these fungi, showing more advantages than obligate anaerobes to decontaminate the environment when present naturally.

Fungos isolados de solo foram avaliados quanto à habilidade em degradarem compostos derivados de lignina pela produção de enzimas ligninolíticas. Os ácidos lignosulfônicos e tânico foram usados separadamente como única fonte de carobono para cultivo dos fungos em 30 dias sob condições microaeróbias. Os fungos foram capazes de crescer e usar tais compostos como fonte de carbono e mostraram produção de lignina-peroxidase, manganês-peroxidase e lacase. Degradações expressivas dos ácidos lignosulfônico e tânico foram verificadas por Cromatografia Liquida de Alta Eficiência (CLAE), indicando grande potencial de uso em processos de biorremediação de macromoléculas aromáticas similares à lignina em ambientes naturais sob condições baixas de oxigenação.