A água de coco contém várias substâncias não caracterizadas e é amplamente utilizada na alimentação humana. Neste estudo, foram detectados e quantificados ácido ascórbico e ácido cafeico e polifenóis totais em diversas variedades de coco, e usando HPLC-MS-MS (25,8 ± 0,6 µg-mL, 1,078 ± 0,013 µg-mL and 99,7 µg-mL, respectivamente, em água de coco do anão verde, ou 10 mg, 539 µg e 39,8 mg por unidades de coco consumido, 500 ± 50 mL). O potencial antioxidante da água de coco das quatro variedades de coqueiro (anão verde, anão amarelo, anão vermelho e amarelo malasiano) foi comparada com água de coco industrializada e água liofilizada da variedade anão verde. Todas as variedades foram eficazes - com destaque para as propriedades antioxidantes do anão verde, uma vez que é o mais comum usado – no sequestro do radical DPPH (IC50=73 µL), óxido nítrico (0,1 mL com IP de 29,9%) e inibindo a produção de espécies reativas com o ácido tiobarbitúrico (1 mL com IP de 34,4%) in vitro. Em cultura de células, a água de coco da variedade anão verde foi eficiente na proteção contra danos oxidativos induzidos por peróxido de hidrogênio.

Coconut water contains several uncharacterized substances and is widely used in the human consumption. In this paper we detected and quantified ascorbic acid and caffeic acid and total phenolics in several varieties of coconut using HPLS-MS-MS (25.8 ± 0.6 µg-mL and 1.078 ± 0.013 µg-mL and 99.7 µg-mL, respectively, in the green dwarf coconut water, or 10 mg and 539 µg and 39.8 mg for units of coconut consumed, 500 ± 50 mL). The antioxidant potential of four coconut varieties (green dwarf, yellow dwarf, red dwarf and yellow Malaysian) was compared with two industrialized coconut waters and the lyophilized water of the green dwarf variety. All varieties were effective in scavenging the DPPH radical (IC50=73 µL) and oxide nitric (0.1 mL with an IP of 29.9%) as well as in inhibiting the in vitro production of thiobarbituric acid reactive substances (1 mL with an IP of 34.4%), highlighting the antioxidant properties of the green dwarf which it is the most common used. In cell culture, the green dwarf water was efficient in protecting against oxidative damages induced by hydrogen peroxide.

Accumulated evidence indicates that oxidative stress plays a role in neurodegenerative diseases, such as Alzheimer, Parkinson and Amyotrophic Lateral Sclerosis. Here, we emphasize the results provided by the technology of genetically modified animals. Studies with transgenic and knockout mice have allowed great advances in the research of oxidative stress in general and in the central nervous system, and are pointing to potential targets for the development of new drugs and therapies to disrupt the cycle of events that lead to neuronal death. Thus, genetically modified animals are a valuable tool for the comprehension of human diseases, including neurodegenerative ones.

5-Aminolevulinic acid (ALA) is a heme precursor accumulated in acute intermittent porphyria (AIP), which might be associated with hepatocellular carcinoma (HCC) in symptomatic patients. Under metal catalyzed oxidation, ALA and its cyclic dimerization product, 3,6-dihydropyrazine-2,5-dipropanoic acid, produce reactive oxygen species that damage plasmid and calf thymus DNA bases, increase the steady state level of 8-oxo-7,8-dihydro-2´-deoxyguanosine in liver DNA and promote mitochondrial DNA damage. The final product of ALA, 4,5-dioxovaleric acid (DOVA), is able to alkylate guanine moieties, producing adducts. ALA and DOVA are mutagenic in bacteria. This review shows an up-to-date literature data that reinforce the hypothesis that the DNA damage induced by ALA may be associated with the development of HCC in AIP patients.