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Bacillus spp. supplementation as probiotics in cultured fish diets has a long history of safe and effective use. Specifically, B. velezensis show great promise in fine-tuning the European sea bass disease resistance against the pathogenicity caused by several members of the Vibrio family. However, the immunomodulatory mechanisms behind this response remain poorly understood. Here, to examine the inherent immune variations in sea bass, two equal groups were fed for 30 days with a steady diet, with one treatment supplemented with B. velezensis. The serum bactericidal capacity against live cells of Vibrio anguillarum strain 507 and the nitric oxide and lysozyme lytic activities were assayed. At the cellular level, the phagocytic response of peripheral blood leukocytes against inactivated Candida albicans was determined. Moreover, head-kidney (HK) total leukocytes were isolated from previously in vivo treated fish with LPS of V. anguillarum strain 507. Mechanistically, the expression of some essential proinflammatory genes (interleukin-1 (il1b), tumor necrosis factor-alpha (tnfa), and cyclooxygenase 2 (cox2) and the sea bass specific antimicrobial peptide (AMP) dicentracin (dic) expressions were assessed. Surprisingly, the probiotic supplementation significantly increased all humoral lytic and cellular activities assayed in the treated sea bass. In addition, time-dependent differences were observed between the control and probiotic treated groups for all the HK genes markers subjected to the sublethal LPS dose. Although the il1b was the fastest responding gene to a significant level at 48 h post-injection (hpi), all the other genes followed 72 h in the probiotic supplemented group. Finally, an in vivo bacteria challenge against live V. anguillarum was conducted. The probiotic fed fish observed a significantly higher survival. Overall, our results provide clear vertical evidence on the beneficial immune effects of B. velezensis and unveil some fundamental immune mechanisms behind its application as a probiotic agent in intensively cultured European sea bass. • B. velezensis strain D-18 as probiotic generates protection in the European sea bass. • Innate humoral and cellular mechanisms show significant enhancements in the animals fed with the probiotic. • In vivo challenge against a pathogenic strain of Vibrio anguillarum was better resolved by the probiotic fortified fish. • The regular use of B. velezensis is suggested as a viable eco-friendly strategy to prevent bacterial diseases in fish culture. [ABSTRACT FROM AUTHOR]

Abstract: The addition of sugar during roasting (torrefacto) has been proposed as a technique to increase the antioxidant capacity. However, other factors such as roasting degree and coffee origin also play a key role. Two batches of Colombian green coffee were roasted adding increased amounts of sucrose (0–15 g per 100 g of coffee) to reach the same roasting degree than a commercial Colombian coffee. Moreover, seven conventional roasted coffees from different origins (Colombia, Brazil, Kenya, Guatemala and Vietnam) and roasting degrees (Dark, Medium and Light), and one 100% Torrefacto roasted coffee were analyzed. Although the addition of sugar during roasting increased the DPPH quenching activity, phenolic compounds (5-caffeoylquinic, caffeic and ferulic acids, and 4-vinylguaiacol) were hardly affected by torrefacto roasting process, showing that Maillard and other roasting reactions products, such as browned-colored compounds including melanoidins (Abs 420 nm), have an important role as antioxidants. Principal Component Analysis (PCA) showed that roasting degree also plays a key role on overall antioxidant activity. Moreover, the Absorbance at 420 nm has been proposed as a good marker of torrefacto roasting process, whereas the roasting degree might be better characterized by L* values. [Copyright &y& Elsevier]