## 1 Introduction  
Resveratrol (3,4\({}^{\prime}\),5-trihydroxystilbene) is a natural product with relevant nutraceutical activity [1]. The content of resveratrol in red wines (1-3 mg L\({}^{-1}\)) and peanuts (0.5-2.5 mg 100 g\({}^{-1}\)) is relatively high. However, continuous consumption of these foods remains controversial due to the coexistence of elevated amounts of ethanol and assimilable carbohydrates [2]. Rigorous in vitro and in vivo studies have revealed the beneficial effects of resveratrol, which are linked to antioxidant, antinflammatory, anti-platelet aggregation, anti-atherogenic, oestrogen-like, immunomodulatory and chemopre activities [1]. Resveratrol has an evident role as a regulator of tumor initiation, promotion and progression [1]. Based on dose-response effects, some studies supported an anti-aging effect which was reported from microorganisms to mammals [3]. Due to these premises, resveratrol is considered as a promising additive for functional foods. Thus far, several engineering approaches have been performed in order to scale the production of _trans_-resveratrol under controlled conditions. Significant advances in the heterologous production of the stilbene have been achieved in bacterial, yeast and plant models [4; 5; 6; 7; 8; 9; 10]. The biosynthesis of resveratrol is comprised of three or four steps which depend on the specific amino acid used as initial precursor (Figure 1). Phenylalanine is transformed into _p_-coumaric acid by phenylalanine ammonia lyase (PAL) and cinnamate 4 hydroxylase (C4H). However, an alternative pathway from tyrosine involves the enzymatic activity of tyrosine ammonia lyase (TAL) to produce _p_-coumaric acid which is subsequently converted into _p_-coumaroyl-CoA by _p_-coumaric-acid coenzyme A ligase (4 CL). _p_-coumaroyl-CoA is finally transformed into _trans_-resveratrol by stilbene synthases (STS) [11]. Considering that plant models have the biochemical machinery to produce _p_-coumaroyl-CoA, the insertion of a single STS under constitutive promoters have resulted in the accumulation of resveratrol in transgenic plants [5; 9; 12]. Contrarily, resveratrol production in microorganisms requires exhaustive strategies which may include simultaneous insertion of PAL, TAL, C4H or chimeric genes containing C4H:STS [13]. Recent improvements on resveratrol yields were achieved from diverse methods. For example, by overexpressing electron carriers such as AtATR2 from Arabidopsis and CYB5 from _S. cerevisiae_ to optimize the activity of C4H [7]. Other strategies included the overexpression or repression of enzymes involved in the transformation amino acidic precursors or malonate assimilating pathway genes, in order to increase initial precursors destined to the generation of resveratrol [10]. To the best of our knowledge, more than 20 different microbial strains have emerged from _S. cerevisiae_ and _E. coli_ as resveratrol producing systems [11; 13]. Interestingly, some of those platforms were able to generate high amounts of resveratrol from basic substrates, such as glucose, fructose or ethanol [6; 7]. Despite these substrates being readily available, other intermediates such as _p_-coumaric acid are still visualized as a non-expensive and more localized alternatives [14]. The amphipathic character of _p_-coumaric acid and its specific location in resveratrol biosynthesis could be considered as two advantages for its use as a substrate in feeding experiments [14]. Coincidently, recent microbial strains that produce resveratrol contain similar combinations of coding sequences isolated from plant, bacterial, fungal or plant species, whereas the last step has been mainly confined to the STS activity of _Vitis vinifera_ and _Arachis hypogaea_[11; 13]. Currently, comparative  
Figure 1: Biosynthesis of resveratrol in higher plants. Keys enzymes are highlighted in red. Phenylalanine ammonia lyase (PAL), tyrosine ammonia lyase (TAL), cinnamate 4 hydroxylase (C4H), _p_-coumaric-acid coenzyme A ligase (4 CL) and stilbene synthases (STS).