Tesis doctoral de Jimena Bravo Ortega
Millions of coffee cups are consumed every day around the world, producing spent coffee grounds in tons. Coffee is highly rich in antioxidants and part of them could still remain in spent coffee grounds after brewing process. Therefore, the objective of the present research was to evaluate the potential antioxidant, genoprotective and neuroprotective effects of spent coffee and to identify the main responsible compounds (chlorogenic acids, caffeine and melanoidins). For that purpose, chemical¿based assays (abts, dpph, total phenolics, esr spectroscopy) and human cells culture assays (mtt, ros and comet assay) were applied in spent coffee extracts from arabica (guatemala) and robusta (vietnam) coffee (medium roast) to generate scientific evidence supporting healthy-beneficial effects. Previously, extraction with neutral water (ph 7.0) in a filter coffeemaker (24g/400ml) was proposed as the best method to obtain spent coffee extracts with high antioxidant capacity. all spent coffee extracts obtained from the most common coffeemakers (filter, espresso, plunger), with the exception of those from the mocha coffeemaker, have relevant antioxidant capacity due to the presence of hydrophilic antioxidants, both phenolics (mono- and dicaffeoylquinic acids) and nonphenolics. Spent coffee from filter and espresso coffeemakers were 4-7 fold richer in dicaffeoylquinic acids (3.31-5.79 mg/g spent coffee) than their respective coffee brews (0.22-1.94 mg/g coffee). The antioxidant capacities of the aqueous spent coffee extracts were 46.0-102.3 % (filter), 59.2-85.6 % (espresso), and <42 % (plunger) in comparison to their respective coffee brews. data from cell culture assays supported the results obtained with chemical-based assays. Spent coffee extracts highly protected hela cells (derived from human cervical cancer) from h2o2-induced oxidative damage, as revealed by the decrease of intracellular generation of reactive oxygen species and dna strand breaks (29-73 % protection). To a lesser extent, spent coffee also protected from induced oxidative dna damage (fpg-sensitive sites, 11.5 % protection). However, spent coffee extracts were not able to protect neuroblastoma cells, before and after a simulated in vitro digestion. therefore, spent coffee can be considered as a good source of hydrophilic bioactive compounds with antioxidant and strong genoprotective properties in human cells, revealing the potential use of these coffee byproducts in food and pharmaceutical industries or even to provide new strategies to protect against oxidative stress related diseases.
Datos académicos de la tesis doctoral «Potential antioxidant, genoprotective and neuroprotective effect of spent coffee«
- Título de la tesis: Potential antioxidant, genoprotective and neuroprotective effect of spent coffee
- Autor: Jimena Bravo Ortega
- Universidad: Navarra
- Fecha de lectura de la tesis: 24/06/2013
Dirección y tribunal
- Director de la tesis
- María Concepción Cid Canda
- Tribunal
- Presidente del tribunal: adela Lopez de cerain salsamendi
- Francisco José Morales navas (vocal)
- María Daglia (vocal)
- laura Bravo clemente (vocal)