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This study was aimed to characterize the secondary metabolites produced by fourColletotrichumspecies,C. acutatum,C. gloeosporioides,C. godetiaeandC. karsti, bothin vitro, on potato dextrose agar (PDA) and oatmeal agar (OA), and during the infection process of fruits of four olive cultivars differing in susceptibility to anthracnose, ‘Coratina’ and ‘Ottobratica’, both susceptible, ‘Frantoio’ and ‘Leccino’, both resistant. The metabolites were extracted from axenic cultures after seven days incubation and from olives at three different times, 1, 3 and 7 days post inoculation (dpi). They were identified using the HPLC-QTOF analysis method. In total, as many as 45 diverse metabolites were identified; of these 29 were detected on infected olives and 26 in axenic cultures on agar media (OA and PDA). Only 10 metabolites were present in both fruits and axenic cultures while 19 were found exclusively on olives and 16 exclusively in axenic cultures. The 45 identified metabolites comprised fatty acid, phenolics, pyrones, sterols, terpenes and miscellaneous compounds. EachColletotrichumspecies produced a different spectrum of metabolites depending of the type of matrices. On artificially inoculated olives the severity of symptoms, the amount of fungal secondary metabolites and their number peaked 7 dpi irrespective of the cultivar susceptibility and the virulence of theColletotrichumspecies. The metabolite profiles as represented by heat maps were the result of the interaction olive cultivar xColletotrichumspecies.

The presence of mycotoxigenic fungi such as Aspergillus, Penicillium, and Fusarium genera represents a problem in food preservation and consequently, its spoilage. During the fermentation process with lactic acid bacteria, a range of secondary metabolites associated with beneficial health effects were released. In the present study, goat whey fermented by Lactobacillus plantarum (CECT 220, 221, 223, and 748) species has shown a satisfactory inhibitory effect against 28 fungi, showing for certain species of Fusarium genus and also, for Aspergillus steynii, a value of minimum inhibitory concentration until 1.95 g/L. In addition, phenyllactic acid was identified in each sample of fermented whey at a concentration ranged from 0.34 to 1.21 mg/L. These results suggest the possible use of fermented whey as a source of new preservatives of natural origin to incorporate in food matrices for the purpose of improving the shelf life. Practical Application: Whey could be a good candidate for use as a natural antifungal agent to incorporate in food matrices. Whey could be used to prevent specific fungal growth that naturally occurs in food preparations. Consequentially, whey could enhance the shelf life of edible products.

Mycotoxins are toxic metabolites produced by various genera of fungi. Fungi belonging to species of the genera Aspergillus and Penicillium are the main source of ochratoxin A (OTA) in wine. The reduction of OTA in must and wine has been studied using physical, chemical, and biological technologies. In this paper, we report on the capacity of different cultures isolated from Tempranillo winegrapes contaminated with fungus to degrade OTA in tryptic soy broth (TSB) medium at pH 3.5 and 6.5. We studied the interaction between OTA and four isolates during alcoholic fermentation of red wine. This study showed that microorganism isolates reduced the content of OTA in TSB medium and in the wine experiment system. The bacterium Lactobacillus rhamnosus exhibited the greatest mean reduction of OTA in TSB medium at both pH values (55%). During the wine fermentation, the yeast Metschnikowia pulcherrima showed the most reduction of OTA (34%). Liquid chromatography with tandem mass spectrometry was used to identify OTA degradation products, particularly α-OTA (m/z = 257) and the sodium adduct of α-OTA with the loss of the coumarin group (m/z = 170). The presence of OTA in must and wines is a problem for food safety. The use of lactic acid bacteria and yeasts during the winemaking process presents an interesting practical solution.

Supplementary material

Phenomenology constitutes a movement which unfolds in different directions: some are nearer to Edmund Husserl’s thoughts (1859–1938), as the orthodox manifestation of the movement; others are further afield, as would be the case of Nicolai Hartmann (1882–1950): his thoughts are considered to be outside the scope of phenomenology, whereas others see him as a heterodox manifestation of the movement. In any case, Hartmann uses phenomenology in order to purify philosophical problems, without disregarding the scientific contribution. This dependence on the sciences is more obvious in his last works, and especially in his Ontology, and this paper will focus on one of its aspects.