Nutraceutical value and safety of tomato fruits produced by mycorrhizal plants

Abstract

Tomato fruit has assumed the status of 'functional food' due to the association between its consumption and a reduced likelihood of certain types of cancers and CVD. The nutraceutical value of tomatoes can be affected by the cultivation conditions, e.g. the phytochemical content of the fruits may increase with the establishment of beneficial mycorrhizal symbioses in the plants. A multidisciplinary study was carried out to gain knowledge on the antioxidant, oestrogenic/anti-oestrogenic and genotoxic activity of tomato fruits produced by mycorrhizal plants. The present results showed that the symbiosis positively affected the growth and mineral nutrient content of tomato plants and enhanced the nutritional and nutraceutical value of tomato fruits through modifications of plant secondary metabolism, which led to increased levels of lycopene in fruits obtained from mycorrhizal plants, compared with controls. Moreover, such changes did not result in the production of mutagenic compounds, since tomato extracts induced no in vitro genotoxic effects. Fruit extracts, both hydrophilic and the lipophilic fractions, originating from mycorrhizal plants strongly inhibited 17-b-oestradiol -human oestrogen receptor binding, showing significantly higher anti-oestrogenic power compared with controls. The present study shows that beneficial plant symbionts, such as mycorrhizal fungi, can lead to the production of safe and high-quality food, which is an important societal issue strongly demanded by both consumers and producers.

Contrasting effects of cover crops on ‘hot spot’ arbuscular mycorrhizal fungal communities in organic tomato

“…Presently, the role of AMF in influencing soil fertility, crop productivity, yield quality and protection against environmental stresses is widely acknowledged (van der Heijden et al 1998;Smith and Read 2008;Giovannetti et al 2012;Berta et al 2013). AMF contribution to crop growth and productivity can be influenced by both interspecific and intraspecific differences (Munkvold et al 2004;Vogelsang et al 2006).…”

The rat glucocorticoid receptor integration in Nicotiana langsdorffii genome affects plant responses to abiotic stresses and to arbuscular mycorrhizal symbiosis

“…As dynamic changes in metabolism and signalling hormonal network may also affect the performance of mycorrhizal symbionts (Hause et al 2007;Giovannetti et al 2012), we analysed the response of transgenic N. langsdorffii plants to the AM fungus F. mosseae. In our experiments, plants expressing GR receptors showed a reduced pre-symbiotic hyphal growth and branching, while maintaining the same levels of mycorrhizal colonization, compared with controls.…”

Gr and hp-1 tomato mutants unveil unprecedented interactions between arbuscular mycorrhizal symbiosis and fruit ripening

“…Fruit phosphorus level is enhanced systemically in fruits by symbiosis (Giovannetti et al 2012) and it is considered as a valuable marker of the symbiosis at systemic level. Fruits from WT MYC plants showed an increase of about 30 % in the phosphorus content, similar to what has been previously reported (Hart et al 2014).…”

“…Fruits from mycorrhizal (MYC) tomato plants have also been found to be enriched in healthy compounds, including amino acids (Salvioli et al 2012) and lycopene (Regvar et al 2003). In addition, they possess a higher anti-oestrogenic power and no in vitro genotoxic effects (Giovannetti et al 2012), as well as an enhanced expression of allergen-encoding genes that do not match with a higher allergenic potential for humans (Schwarz et al 2011). A deeper mRNA-seq transcriptome analysis (Zouari et al 2014) provided a more exhaustive molecular framework for fruits from tomato MYC plants.…”