Evaluation of Antibacterial Activity of Various Commercial Essential Oils

Essential oils and their components are becoming increasingly popular as naturally occurring antimicrobial agents. In this work the chemical composition and the antibacterial properties of the essential oils of rosemary (Rosmarinus officinalis), lemon (Citrus limonum), oregano (Corydothymus capitatus) and thyme (Thymus vulgaris) were determined. The essential oil components were identified by GC/MS analysis. The antibacterial activity of the oils was investigated in order to evaluate its efficacy against a panel of standard reference strains, using disc diffusion and minimum inhibitory concentration (MIC) methods. The GC/MS analysis showed that the major constituents of the oils were monoterpene hydrocarbons and phenolic monoterpenes, but the concentration of these compounds varied greatly among the oils examined. The results of the antibacterial assay showed that Corydothymus capitatus and Thymus vulgaris have the strongest antibacterial activity against all microorganisms tested. The MIC values obtained in the presence of Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Salmonella arizonae were ≤ 0.25% (v/v) for oregano and thyme essential oils

Identification of peptides with antioxidant and antihypertensive capacities by RP-HPLC-Q-TOF-MS in dry fermented camel sausages inoculated with different starter cultures and ripening times

Low molecular weight peptides are produced during meat fermentation. They contribute to generate flavor compounds but they can also exert certain bioactivities. The aim of this work was to evaluate, for the first time, the generation of bioactive peptides during the preparation of dry fermented camel sausages and to study the influence of the ripening time and the starter culture on bacteria growing, peptide concentration and size, and antioxidant and antihypertensive capacities of peptides. Camel meat sausages inoculated with different starter bacteria and non-inoculated were ripened up to 28 days. Results demonstrated that bacteria population, peptide concentration, and peptide size were affected by the ripening time and the inoculated bacteria. Moreover, the ripening process resulted in an increasing antioxidant and antihypertensive capacity showing the highest bioactivities in fractions with peptides below 3 kDa. Peptides in these fractions were identified by RP-HPLC-Q-TOF-MS analysis. Identified peptides showed common features with peptides with antioxidant or anti hypertensive activity

Antihypertensive peptides from animal proteins

Hypertension is considered a major health problem throughout the world among adults, adolescents, as well as children and several preventive and therapeutic interventions are available. In addition to the pharmaceutical drugs and lifestyle changes, significant milestones have been achieved in the past decades in the identification of bioactive peptides from animal proteins with useful antihypertensive activities. The antihypertensive properties of these peptides are attributed to several mechanisms ranging from mineral-binding, opioid-like and antithrombotic properties to inhibition of ACE (angiotensin-converting enzyme). ACE-inhibitory peptides are the most widely studied bioactive peptides with promising potential in hypertension management. In addition to milk and dairy products, which are the major sources of antihypertensive peptides, a remarkable increase has been observed in the documentation of peptides from other animal proteins, such as meat, with demonstrated in vitro and in vivo antihypertensive properties. Numerous opportunities exist in the global market for the development of novel food products and additives based on these antihypertensive peptides for the dietary management of hypertension. This chapter reviews the antihypertensive peptides derived from meat proteins and examines their possible role as a functional ingredient in foods for the management of hypertension