**Author details**

have been associated with synthetic products consumption. Flavonoids are phytochemicals that cannot be synthesized by humans; however, these compounds may be used as food addi‐ tives to improve health‐beneficial effects and increase their amount in humans [69, 70].

Flavonoids are present in significant amounts in many fruits and vegetables; natural antioxi‐ dants and flavonoids have been reported as two of the most important micronutrients, which can be used in industry to reduce the use of synthetic compounds on foods and improve health in humans due their potential to decrease several diseases. These bioactive compounds can be used to prolong shelf‐life and preserve many foods due to their antimicrobial and antioxidant properties [44]. Moreover, in recent years interest in acquiring ever more natural products has grown; this has been caused by restriction over the use of synthetic antioxidants in food (such as BHA and BHT) and increase the use of natural compounds such as antioxi‐ dants or food components, which have relatively low toxicity compared to synthetic products

Flavonoids are suitable compounds that may be used as food preservative due to their benefi‐ cial effects that have been demonstrated before: prevention of fat and oils oxidation, supple‐ ment for animal feeds, protection of vitamins and enzymes, inhibition of microbial growth in foodstuffs and health functional ingredient in foods and dietary supplements [68]. The most studied applications of flavonoids in foods are in red meats and poultry to inhibit lipid oxida‐ tion, use of natural extracts in foods as functional ingredients and retard spoilage microor‐ ganism growth in meats. Some studies have indicated that these compounds have protective

Recently, flavonoids have gained attention due their antioxidant properties, which can act against oxygen free radical and lipid peroxidation [71]. Many studies have mentioned that *in vitro* antioxidant activity of these compounds depends on the arrangement of functional groups on its structures; however, the mechanism of their antioxidant activity is substan‐ tially influenced by their configuration and total number of hydroxyl groups presents in the flavonoid molecule and the glycosylation of flavonoid molecule, but could be increased by

The protective effect of flavonoids in biological systems is attributed to their antioxidant activ‐ ity due to their capability to donate a hydrogen atom [58]. However, it is important to con‐ sider the antioxidant effect *in vivo*, which can be different comparing with *in vitro* assays: (i) low concentration on systemic circulation compared with endogenous and exogenous anti‐ oxidant compounds, (ii) high level of biotransformation that flavonoids suffer during their absorption and distribution in the body, which can decrease their antioxidant activity and (iii) large doses of flavonoids may decrease bioavailability of trace elements, such vitamins, folic

Plant bioactive compounds (primarily flavonoids) have been used in dermatology and cos‐ metic preparations for a long time due to several associated properties such as antioxidant,

[57, 65].

effect on meat quality and other products [67].

362 Flavonoids - From Biosynthesis to Human Health

polymerization of flavonoid monomers [58, 72, 73].

acid or other antioxidants [4, 74].

**7. Other applications**

Saul Ruiz‐Cruz<sup>1</sup> \*, Saraí Chaparro‐Hernández<sup>1</sup> , Karen L. Hernández‐Ruiz<sup>1</sup> , Luis A. Cira‐Chávez<sup>1</sup> , María I. Estrada‐Alvarado<sup>1</sup> , Laura E. Gassos Ortega1 , José de Jesús Ornelas‐Paz<sup>2</sup> and Marco A. Lopez Mata<sup>3</sup>

\*Address all correspondence to: sruiz@itson.edu.mx

1 Department of Biotechnology and Food Sciences, Institute Technological of Sonora, Sonora, México

2 Center for Research in Food and Development, Chihuahua, México

3 Department of Health Sciences, University of Sonora, Campus Cajeme, Sonora, México
