In Vitro Antioxidant and Antimicrobial Activities of Spanish Honeys

Sixty-seven Spanish honeys from different floral origins, nectars and honeydews, were examined for potential antimicrobial and antioxidant activities. Antioxidant capacities were determined in terms of their antiradical capacity using the stable free radical DPPH*. The bacterial species Micrococcus luteus and Staphylococcus aureus were used as the resistant microorganism in the antibacterial assays. The results showed that honeydew honeys presented higher antioxidant capacities than nectar honeys. On the other hand, honey capacity to inhibit Micrococcus luteus and Staphylococcus aureus was firstly evaluated by an agar diffusion method. Secondly, the active samples were tested with a spectrophotometic method to quantify their "non-peroxide" antimicrobial capacity to inhibit Staphylococcus aureus . We did not observed any relationship between the physicochemical parameters of the samples, and their ability to inhibit these microorganisms. The results obtained by the spectrophotometric method show that this method is easy and useful in the evaluation of the antibacterial capacity of honeys.