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Lactobacillus fermentum is a probiotic that belongs to the group of lactic acid bacteria and presents high intestinal colonization capacity after oral administration. To maintain its quality during manufacturing to its expiration, the physical and chemical stability of the probiotic remains a major challenge and concern. This work aimed to determine the thermal degradation parameters of the probiotic Lactobacillus fermentum by thermogravimetry (TG), calculated using the Arrhenius mathematical model. The probiotic degradation followed a second-order kinetics, where the rate of its degradation depends on the concentration of two or more reactants, presenting degradation rate constant of 6.23 × 10−10 min−1 at 25 °C and an activation energy of 21,987 cal mol−1. The value corresponding to the simulate shelf life was also obtained. TG is an extremely useful tool, simple and fast to determine the degradation rate parameters of the compounds including pharmaceuticals and nutraceuticals. The shelf life needs to be defined by realist data. This is the first time that was used TG to determine the degradation reaction of probiotics.

This study aimed to evaluate tough lovegrass leaf and root extracts antimicrobial activity. The extracts (plant material: solvent, 1:10) were prepared by maceration with methanol:water (1:1) during ten days followed by a concentration in a rotary evaporator under reduced pressure. The extracts were resuspended in water containing 1% of dimethylsulfoxide (DMSO) to obtain a final concentration of 100 mg/mL and then filtered through a sterilizing membrane with 0.22μm. The antibacterial activity of the leaf and root extracts were evaluated against pathogenic and phytopathogenic bacteria by agar well diffusion and microdilution broth methods for the minimum inhibitory concentrations (MIC) determination. The antifungal activity of tough lovegrass leaf and root extracts were evaluated by micelial growth inhibition and conidial germination inhibition. The extracts presented low antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Xanthomonas translucens, but the leaf extracts presented significant antifungal activity against the phytopathogenic fungus Drechslera tritici-repentis. The results support the continuity of the study in improving the effectiveness of the active extract for a possible use in pharmacology and agronomy and in attempting to determine the probable active antimicrobial compound.

Colletotrichum truncatum and Sclerotinia sclerotiorum are fungal pathogens that can be disseminated by soybean seed, and they are usually controlled by seed treatment with fungicides. However, due to the harmful effects of pesticides on the environment and human health, the search for alternative methods to control seed-borne pathogens is necessary. Thus, this study evaluated whether the extract of Diaporthe infecunda, an endophyte from Schinus terebinthifolius leaves, inhibits the growth of C. truncatum and S. sclerotiorum, and improves the sanitary quality of soybean seeds. Initially, diffusion in agar assays with a D. infecunda extract were carried out. It was shown that the extract results in an inhibition of 94.4% and 83.8% of mycelial growth of C. truncatum and S. sclerotiorum, respectively. In a second study, soybean seeds were artificial inoculated with C. truncatum and S. sclerotiorum separately for each pathogen species with a water restriction technique using mannitol. The treatments consisted of: T1 = synthetic fungicide (thiophanate-methyl + fluazinam); T2 = D. infecunda extract (10 mg mL−1); T3 = solvent only (methanol:water); T4 = D. infecunda extract + fungicide; T5 = non-treated seeds; T6 = non-inoculated and non-treated seeds. The incidence of C. truncatum and S. sclerotiorum was reduced with the use of D. infecunda extract (12% and 10%, respectively) compared to the non-treated seeds (35% and 52%, respectively). However, there was a decrease in the seed germination with the D. infecunda extract. In conclusion, the extract of D. infecunda has potential to be used in seed treatment of soybean to control C. truncatum and S. sclerotiorum, however, further studies are required due to the decrease in seed germination.

Fusarium head blight (FHB) is a disease of wheat caused by the Fusarium graminearum species complex in which Fusarium meridionale is included. The seed is an inoculum source and the use of inoculated seeds for this pathosystem studies can optimize the time of experimental tests. However early germination of seed during the inoculation process can make studies on the FHB pathosystem very challenging. Therefore, this study aimed to determine the optimal water restriction condition and time of exposure for inoculation of F. meridionale in wheat seeds without reducing seed germination, to define a reliable and rapid technique for inoculating FHB using wheat seeds. Mycelial discs of F. meridionale were placed in the center of Petri dishes containing potato dextrose agar (PDA) media with different quantities of mannitol to establish water potentials of −0.4, −0.6, −0.8, −1.0 or − 1.2 MPa. A control plate with only PDA had −0.36 MPa. Mycelial growth was measured for 178 hours post inoculation (hpi). Wheat seeds were placed in contact with the mycelium at 12, 24, 36, 48 or 60 hpi. Seed germination and seed pathology were evaluated. The greatest growth of the pathogen was at water potentials between −0.8 and − 1.06 MPa. Seed germination was not affected by the water potential at 12 hpi. It was verified that at −1.0 MPa the seeds did not germinate early, and the pathogen was detected in 100% of the inoculated seeds. Thus, the use of mannitol at water potential of −1.0 MPa and seed contact with the pathogen at 12 hpi is a method that can be used for inoculation of F. meridionale in wheat seeds.

Citrus black spot disease, caused by the phytopathogen Phyllosticta citricarpa, depreciates the market value of citrus fruits and prevents their exportation to disease-free regions. It may also reduce the productivity of citrus fruit orchards. To identify an alternative to conventional disease control measures, isolates of Diaporthe terebinthifolii, active against P. citricarpa, were selected from an endophytic fungal population of Schinus terebinthifolia leaves. Different culture media were screened to identify the culture medium that afforded the most efficient production of biologically active extracts. A particular fraction (fraction VI) of the extract completely protected orange leaves by inhibiting the germination of P. citricarpa conidia with a minimum inhibitory concentration of 0.003 μg.mL-1. The active constituents in D. terebinthifolii extract fractions were identified by gas chromatography coupled to mass spectrometry as verbanol, phenylethyl alcohol, verbenyl acetate and methyl hexadecanoate. The results obtained strongly suggest the existence of a synergistic effect among the metabolites produced. Thus, these fungal metabolites could be used to control the CBS disease. As the asexual spores of P. citricarpa play an important role in fruit lesion development and disease dispersion, fungal extracts that inhibit the spore germination can be used as an effective alternative for directional disease control.

In this study, we analyzed the antimicrobial activity of extracts harvested from 17 endophytic fungi isolated from the medicinal plant Schinus terebinthifolius. Morphological and molecular analyses indicated that these fungal species belonged to the genera Alternaria, Bjerkandera, Colletotrichum, Diaporthe, Penicillium, and Xylaria. Of the endophytes analyzed, 64.7 % produced antimicrobial compounds under at least one of the fermentation conditions tested. Nine isolates produced compounds that inhibited growth of Staphylococcus aureus, four produced compounds that inhibited Candida albicans, and two that inhibited Pseudomonas aeruginosa. The fermentation conditions of the following endophytes were optimized: Alternaria sp. Sect. Alternata—LGMF626, Xylaria sp.—LGMF673, and Bjerkandera sp.—LGMF713. Specifically, the carbon and nitrogen sources, initial pH, temperature, and length of incubation were varied. In general, production of antimicrobial compounds was greatest when galactose was used as a carbon source, and acidification of the growth medium enhanced the production of compounds that inhibited C. albicans. Upon large-scale fermentation, Alternaria sp. Sect. Alternata—LGMF626 produced an extract containing two fractions that were active against methicillin-resistant S. aureus. One of the extracts exhibited high activity (minimum inhibitory concentration of 18.52 µg/mL), and the other exhibited moderate activity (minimum inhibitory concentration of 55.55 µg/mL). The compounds E-2-hexyl-cinnamaldehyde and two compounds of the pyrrolopyrazine alkaloids class were identified in the active fractions by gas chromatography-mass spectrometry.

This study aimed to evaluate tough lovegrass leaf and root extracts antimicrobial activity. The extracts (plant material: solvent, 1:10) were prepared by maceration with methanol:water (1:1) during ten days followed by a concentration in a rotary evaporator under reduced pressure. The extracts were resuspended in water containing 1% of dimethylsulfoxide (DMSO) to obtain a final concentration of 100 mg/mL and then filtered through a sterilizing membrane with 0.22μm. The antibacterial activity of the leaf and root extracts were evaluated against pathogenic and phytopathogenic bacteria by agar well diffusion and microdilution broth methods for the minimum inhibitory concentrations (MIC) determination. The antifungal activity of tough lovegrass leaf and root extracts were evaluated by micelial growth inhibition and conidial germination inhibition. The extracts presented low antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Xanthomonas translucens, but the leaf extracts presented significant antifungal activity against the phytopathogenic fungus Drechslera tritici-repentis. The results support the continuity of the study in improving the effectiveness of the active extract for a possible use in pharmacology and agronomy and in attempting to determine the probable active antimicrobial compound.

Este estudo teve como objetivo compreender as estratégias adotadas pelas pequenas e médias empresas (PMEs) do Oeste de Santa Catarina para a internacionalização. O método de pesquisa utilizado trata-se de pesquisa qualitativa, a coleta de dados ocorreu por meio de entrevista semiestruturada, a amostra foi composta por três gestores de empresas da região oeste de Santa Catarina, participantes do Programa Exporta – SC, projeto realizado por intermédio do Sebrae. Os dados foram analisados por meio da técnica de análise do conteúdo. Os resultados apresentam que a forma de internacionalização das três empresas compreendeu o modelo de Uppsala (Teoria Comportamental) e o modo de entrada utilizado foi a exportação. Esta pesquisa apresentou como contribuição empírica a compreensão da atuação estratégica de PMEs que busca a internacionalização como uma forma de crescimento e desenvolvimento econômico.

Este estudo teve como objetivo compreender as estratégias adotadas pelas pequenas e médias empresas (PMEs) do Oeste de Santa Catarina para a internacionalização. O método de pesquisa utilizado trata-se de pesquisa qualitativa, a coleta de dados ocorreu por meio de entrevista semiestruturada, a amostra foi composta por três gestores de empresas da região oeste de Santa Catarina, participantes do Programa Exporta – SC, projeto realizado por intermédio do Sebrae. Os dados foram analisados por meio da técnica de análise do conteúdo. Os resultados apresentam que a forma de internacionalização das três empresas compreendeu o modelo de Uppsala (Teoria Comportamental) e o modo de entrada utilizado foi a exportação. Esta pesquisa apresentou como contribuição empírica a compreensão da atuação estratégica de PMEs que busca a internacionalização como uma forma de crescimento e desenvolvimento econômico.