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Herein, two shiitake fractions were obtained: the ergosterol-enriched fraction exerted higher in vitro hypocholesterolemic activity and the β-glucan-enriched fraction reduced the cholesterol levels in mice.

Tuber melanosporum cultivation, fruitbody traits are gaining relevance due to their increasing prominence on prices. We investigated the edaphic and temporal patterns of fruitbody traits and characterised the effect of truffle nests (localised peat-based amendment supplemented with T. melanosporum spores) on traits. We monitored fruitbody traits throughout two fruiting seasons in three blocks along a soil gradient. Each trait followed specific edaphic and temporal patterns. The number of fruitbodies per dig and spore maturity followed characteristic within-season trends, whereas fruitbody weight and infestation by truffle beetles were subject to complex interactions among edaphic and temporal variables, suggesting a relevant influence of annual environmental conditions. The application of truffle nests increased fruitbody depth, improved its shape and decreased infestation by truffle beetles. Nests increased the number of fruitbodies per dig, but only in two of the soils, suggesting a relevant role of the bulk soil/substrate interface in fruiting initiation. These results outline a complex scenario, with each trait being differently affected by environmental factors. In this scenario, nests proved to effectively modify several traits, although not always in the desired direction. The European black truffle (Tuber melanosporum) is an ectomycorrhizal fungus highly appreciated in "haute cuisine" due to its organoleptic properties. It grows wild in open oak forests of southern Europe, although nowadays most T. melanosporum production is harvested in orchards planted with seedlings previously inoculated in controlled conditions. Truffle cultivation has advanced greatly in recent decades and has expanded worldwide 1. This is leading to an increased and more stable supply of truffles to markets in recent years, thus encouraging price differentiation by quality 2. Commercial quality standards are defined by both pre-harvest fruitbody (FB) traits and post-harvest practices 3. The most important among the former are FB ripeness, gleba colour (associated to spore maturity), abiotic and biotic damages, fresh weight and shape 4. Despite recent advances, truffle cultivation is not completely domesticated yet, as the uncertainties around the mating process and the FB formation process remain 5,6. The environmental mechanisms triggering fruiting and influencing FB development and maturation are still poorly understood 6,7. Edaphic and climatic factors have a key role in ectomycorrhizal FB yields, phenology and morphology 8-10. This is particularly likely to apply to truffles, which grow below ground and require several months to develop and ripen 11,12. Information on the influence of environmental factors on FB traits could help to clarify the ecology of T. melanosporum and could be useful for improving productivity and sustainability in truffle cultivation. Unraveling the linkages between FB traits and edaphoclimatic conditions is difficult because: (1) the long period of formation of truffle FBs hinders the identification of ...

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The effects of electron-beam or gamma irradiation (both applied at 1.5 kGy and 2.5 kGy) and subsequent storage under modified atmospheres (35 d at 4 °C) were evaluated on total carbohydrates, chitins, β-glucans, proteins, total phenols, sterols and ergocalciferol concentrations of Tuber melanosporum ascocarps. Irradiation procedures reduced chitin and protein concentrations and modified total phenol levels depending on the dose and irradiation type utilized. Further storage of irradiated truffles maintained the levels of all determined compounds unchanged except for the phenolic compounds and ergosterol levels that increased probably due to their yeast colonization after 21 d storage. Therefore, irradiation plus storage under modified atmosphere packings could be used as a preservation method to extent truffles quality and shelf life, but it is only recommended up to 21 d. The lower irradiation doses are encouraged to diminish protein degradation.

The use of alternative ingredients in the production of kombucha has seen a recent increase. Our research aimed to characterize the chemical, nutritional, microbial, and aromatic profiles of kombucha beverages prepared with strawberry tree (Arbutus unedo) fruits fermented with three different SCOBYs for 21 days. The analyses showed similar levels of microbiological groups (aerobic mesophilic microorganisms, lactic acid bacteria, acetic acid bacteria, and yeasts)among the SCOBYs used. The beverages studied displayed a decrease in pH value and carbohydrate content, and protein degradation was also observed as fermentation progressed. However, the increase in total phenolic compounds during the first week proved to be a point of interest. A total of 20 volatile organic compounds were detected, giving different sensory qualities to the beverages: higher ethanol, benzaldehyde-4-ethyl, or acetic acid depending on the SCOBY used. The results obtained indicated that strawberry tree kombucha might be an alternative beverage with notable nutritional and aromatic properties, with fermentation time and SCOBY composition being identified as crucial factors.