Phytochemicals of Avocado Residues as Potential Acetylcholinesterase Inhibitors, Antioxidants, and Neuroprotective Agents

Abstract

Avocado (Persea americana) is a widely consumed fruit and a rich source of nutrients and phytochemicals. Its industrial processing generates peels and seeds which represent 30% of the fruit. Environmental issues related to these wastes are rapidly increasing and likely to double, according to expected avocado production. Therefore, this work aimed to evaluate the potential of hexane and ethanolic peel (PEL-H, PEL-ET) and seed (SED-H, SED-ET) extracts from avocado as sources of neuroprotective compounds. Minerals, total phenol (TPC), total flavonoid (TF), and lipid contents were determined by absorption spectroscopy and gas chromatography. In addition, phytochemicals were putatively identified by paper spray mass spectrometry (PSMS). The extracts were good sources of Ca, Mg, Fe, Zn, ω-6 linoleic acid, and flavonoids. Moreover, fifty-five metabolites were detected in the extracts, consisting mainly of phenolic acids, flavonoids, and alkaloids. The in vitro antioxidant capacity (FRAP and DPPH), acetylcholinesterase inhibition, and in vivo neuroprotective capacity were evaluated. PEL-ET was the best acetylcholinesterase inhibitor, with no significant difference (p > 0.05) compared to the control eserine, and it showed neither preventive nor regenerative effect in the neuroprotection assay. SED-ET demonstrated a significant protective effect compared to the control, suggesting neuroprotection against rotenone-induced neurological damage.

Phytochemical Profiling, Antioxidant, Antimicrobial and Cholinesterase Inhibitory Effects of Essential Oils Isolated from the Leaves of Artemisia scoparia and Artemisia absinthium

“…It has been observed that oleic acid binds to different allostatic sites of enzyme by interaction to OH and NH 3 functional groups at cystine 319 and tyrosine 320 and show some non-competitive reversible inhibition [ 53 ]. The literature suggests that various plant extracts containing smaller amounts of oleic acid have shown promising anti-cholinesterase effects [ 54 , 55 ]. However, the major effect has been observed against BChE in many cases.…”

Neuroprotective Effects of Agri-Food By-Products Rich in Phenolic Compounds

“…Catechin was reported to be the most promising anti-AD compound for its low binding energy for AChE [ 88 ]. Then, other reports of AChE inhibitory activity where the catechin content was high enough could be also explained [ 67 , 78 , 83 ]. Ben Rejeb et al (2020) stated that extracts from artichoke by-products (leaves, bracts and stems) inhibited AChE and BChE activity, and they related this to the presence of flavonoids in a positive and significant way [ 93 ].…”

Short Review on Bioactive Compounds Recovered From Vegetal Waste as a New Tool in Diabetes, Obesity and Dyslipidaemia Prevention and Treatment

“…An alternative to reduce the amount of unexploited waste with a negative impact on the environment is represented by their valorisation through green extraction, isolation and purification of bioactive compounds in order to obtain added value products, useful in the prevention and treatment of various maladies. Numerous studies have shown that vegetable waste is an important and low-cost source of primary and secondary metabolites with medicinal and nutritional value, such as phenolic compounds (phenolic acids [20,38,67,76], flavonoids [14,18,20,22,23,34,42,56,65,71,74], anthocyanins [20,21,35,57,71], vitamins (vitamin A [25], vitamin E [21], vitamin D [25], vitamin C [21,25,65,74], amino acids [25], alkaloids [11,18], glucosinolates [23], fatty acids [21], poly-saccharides [55], terpenes [14,38,57,74].…”