| Popis: |
Infectious diseases are the world’s leading cause of premature deaths, killing almost 50,000 people every day. In recent years, drug resistance to human pathogenic bacteria has been commonly reported from all over the world (N’guessan et al., 2007). The abusive and indiscriminate use of antimicrobial compounds over many years is the main factor responsible for the appearance of the phenomenon of bacterial resistance to such compounds (Andremont, 2001). With increased incidence of resistance to antibiotics, natural products from plants could be interesting alternatives (Lu et al., 2007; Mbwambo et al., 2007). Some plant extracts and phytochemicals are known to have antimicrobial properties, and can be of great significance in therapeutic treatments. In the last few years, a number of studies have been conducted in different countries to demonstrate such efficacy (BenoitVical et al., 2006; Senatore et al., 2007; Singh et al., 2007). On the other hand, free radicals are known to be the major cause of various chronic and degenerative diseases. Oxidative stress is associated with pathogenic mechanisms of many diseases including atherosclerosis, neurodegenerative diseases, cancer, diabetes and inflammatory diseases, as well as aging processes. It is defined as an imbalance between production of free radicals and reactive metabolites, so-called oxidants, and it also includes their elimination by protective mechanisms, referred to as antioxidative systems. This imbalance leads to damage of important biomolecules and organs with potential impact on the whole organism. Antioxidants can delay, inhibit or prevent the oxidation of oxidizable materials by scavenging free radicals and diminishing oxidative stress (Durackova, 2010; Reuter et al., 2010). Natural antioxidants have been studied extensively for decades in order to find compounds protecting against a number of diseases related to oxidative stress and free radical-induced damage. To date, many plants have been claimed to pose beneficial health effects such as antioxidant properties (Kaur & Arora, 2009; Newman & Cragg 2007). According to World Health Organization (WHO), 65 80% of the world populations rely on traditional medicine to treat various diseases (Kaur & Arora, 2009). The WHO recommends |
