**Acknowledgements**

All plant extracts tested and isolated phenolic acids exhibited a dose-dependent inhibitory effect on MPO activity performed with SIEFED (**S**pecific **I**mmunological **E**xtraction **F**ollowed by **E**nzymatic **D**etection) technic. The SIEFED method used to measure MPO activity allowed the detection of compounds that have a direct interaction with the MPO. For the Hibiscus, dichloromethane extracts showed a stronger inhibition of MPO in comparison to methanolic extracts in the following order: *H. cannabinus* > *H. acetosella* > *H. sabdariffa*. The dichloromethane allowing a better extraction of lipophilic molecules may allow a better interaction of these molecules with the hydrophobic pocket at the entrance of the active site of MPO [16]. Tsumbu et al. evaluated the antioxidant, anti-radical, anti-inflammatory, and modulating properties of in "inflammation like" conditions of green vegetables from Bas Congo in DRC [36]. These authors showed that *Abelmoschus esculentus*, *Hibiscus acetosella*, *Manihot esculenta* and *Pteridium aquilinum* were active to inhibit MPO activity and the best effects were observed for *Pteridium* which contains the highest amount of total polyphenols and tannins, and *Manihot*, which has a high content of flavonoids [36]. Caffeoylhydroxycitric acid and neochlorogenic acid isolated from Hibiscus species, are less efficient MPO inhibitors in comparison to gallic acid compared to gallic acid, caffeoyl-hydroxycitric acid and neochlorogenic acid are larger molecules that cannot enter easily into the active site of MPO and thus inhibit the enzyme [16]. Gallic acid and caffeic acid were less active than quercetin. Quercetin

Although many phytochemicals present in plant foods are poorly absorbed and undergo rapid excretion, they exert anti-inflammatory, antioxidant, and anticarcinogenic effects at realistic doses. Consumption of phytochemicals may also mediate neurohormetic response through the modulation of adaptive stress-resistance genes, which are responsible for encoding protein chaperones that favor resistance to cellular stress and modulate immune function. Thus, regular consumption of phytochemicals from childhood to adulthood may reduce the

Polyphenols are promising neuroprotective agents for the treatment of neurodegenerative diseases and act by different mechanism including a potential to protect neurons against injury induced by neurotoxins, an ability to suppress neuroinflammation, and the potential to promote memory, learning and cognitive function. Evidence for neuroprotection has been provided by *in vitro* studies showing that various polyphenols protect neuronal cells from damage due to oxidative stress, and by *in vivo* animal studies that have shown their ability to

Traditional foods are good source of essential amino acids and minerals especially for children who are exposed to many diseases. The high nutritive value of these traditional vegetables associated with their important antioxidant activities could contribute to a diversification of the diet in konzo's population, and could then provide benefits leading to a protection

The diet of the population of Kahemba is largely dependent on cassava. Biodiversity of the flora of Kahemba constitutes an untapped reserve of traditional food resources that have

against oxidative damage under different conditions including konzo.

shown the best activity than his glycosylated flavonoids [8].

risk of age related neurological disorders [32].

130 Antioxidants in Foods and Its Applications

protect neurons against oxidative insults [12].

**5. Conclusion and perspectives**

The authors thank Dr. Pieter Stofelen and Mrs. Bibiche Mato of the National Botanical Garden of Meise, Belgium, and Professor Dibaluka and Mr. Anthony Kikufi of the Biology Department of University of Kinshasa for identification of specimens. They thank the community of Kahemba and nurse Dieudonné Kasenia (Kwango Province, DRC) for their participation. They thank also the Center for Oxygen, Research and Development (C.O.R.D.) for her scientific and technical supports.
