Background: Botrytis cinerea CCg378 is a wild-type strain infected with two types of double-stranded RNA (dsRNA) mycoviruses and which presents hypovirulence-associated traits. The objectives of the present study were to characterize the mycoviruses and investigate their relationship with the low virulence degree of the fungal host. Results: B. cinerea CCg378 contains five dsRNA molecules that are associated with two different types of isometric viral particles of 32 and 23 nm in diameter, formed by structural polypeptides of 70-kDa and 48-kDa, respectively. The transfection of spheroplasts of a virus-free strain, B. cinerea CKg54, with viral particles purified from the CCg378 strain revealed that the 2.2-kbp dsRNAs have no dependency on the smaller molecules for its stable maintenance in the fungal cytoplasm, because a fungal clone that only contains the 2.2-kbp dsRNAs associated with the 32-nm particles was obtained, which we named B. cinerea CKg54vi378. One of the 2.2 kbpdsRNA segments (2219 bp) was sequenced and corresponds to the gene encoding the capsid protein of B. cinerea CCg378 virus 1 (Bc378V1), a putative new member of the Partitiviridae family. Furthermore, physiological parameters related to the degree of virulence of the fungus, such as the sporulation rate and laccase activity, were lower in B. cinerea CCg378 and B. cinerea CKg54vi378 than in B. cinerea CKg54. Additionally, bioassays performed on grapevine leaves showed that the CCg378 and CKg54vi378 strains presented a lower degree of invasiveness on the plant tissue than the CKg54 strain. Conclusions: The results show that B. cinerea CCg378 is coinfected by two mycoviruses and that the 2.2-kbp dsRNAs correspond to the 32-nm mycovirus genome, which would be a new member of the Partitiviridae family as it has the typical pattern of partitiviruses. On the other hand, the results suggest that the hypovirulence of B. cinerea CCg378 could be conferred by both mycoviruses, since the fungal clone B. cinerea CKg54vi378 presents an intermediate virulence between the CKg54 and CCg378 strains. Therefore, the putative partitivirus would be partially contributing to the hypovirulence phenotype of the CCg378 strain.

Background: There is an emerging field to put into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au³⁺ toxicity through a combination of biochemical and molecular approaches. Results: We found that Au³⁺ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. Conclusions: Au³⁺ is toxic for E. coli because it triggers an unbalance of the bacterium’s oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.

Microalgae grow rapidly, require minimal space, can proliferate in non-agricultural land, do not compete with human food sources, and can be cultivated in a variety of environments, including wastewater. They are considered an ecological source of bioactive compounds, offering an environmentally friendly alternative to conventional industrial production methods, which are often resource-intensive. It is important to emphasize that both the species of microalgae and the specific culture conditions play a decisive role in the generation and storage of valuable bioactive compounds, which can act as biostimulants. Biostimulants are organic compounds or microorganisms capable of enhancing crop quality parameters by optimizing nutrient and water use efficiency, while also strengthening tolerance to abiotic stress. The aim of this article is to provide an updated understanding of biostimulants, their modes of action, and their role in regulating plant responses to abiotic stress. It further incorporates examples of successful trials that demonstrate the advantageous applications of microalgae-based biostimulants, while also addressing the barriers and limitations to their commercialization and integration into sustainable agricultural practices.

(1) Introduction: Chlorogenic acids and caffeine are relevant bioactive compounds present in coffee, known for their antioxidant properties and potential health benefits. However, their concentration may vary depending on the type and preparation of coffee. (2) Objec-tive: This study aimed to quantify total chlorogenic acids and caffeine in different com-mercial coffee samples (instant, freeze-dried and whole bean), and to evaluate their anti-oxidant capacity. (3) Results: Higher concentrations of total chlorogenic acids per serving were observed in freeze-dried and medium-roast powdered coffee, while the highest presence of caffeine per serving was detected in medium-roast powdered coffee. Decaf-feinated coffees showed the lowest values for both compounds. The antioxidant capacity of instant coffees was higher than that of beans measured per serving but did not differ significantly from each other when normalizing the concentrations per mass. The medi-um roasted coffee beans had a significantly higher antioxidant capacity than the others. (4) Conclusion: The differences in composition suggest that coffee type, processing method and degree of roasting significantly influence the content of total chlorogenic acids, caf-feine and antioxidant capacity of the final product.