Potato Peels and Their Bioactive Glycoalkaloids and Phenolic Compounds Inhibit the Growth of Pathogenic Trichomonads

Abstract

Potato peel, a waste product of the potato processing industry, is high in bioactive compounds. We investigated the in vitro antitrichomonad activity of potato peel powders prepared from commercial Russet, red, purple, and fingerling varieties as well as several known potato components, alkaloids and phenolic compounds, against three pathogenic strains of trichomonads. Trichomonas vaginalis is a sexually transmitted protozoan parasite that causes the human disease trichomoniasis. Two distinct strains of the related Tritrichomonas fetus infect cattle and cats. The glycoalkaloids α-chaconine and α-solanine were highly active against all parasite lines, while their common aglycone solanidine was only mildly inhibitory. α-Solanine was several times more active than α-chaconine. The phenolic compounds caffeic and chlorogenic acids and quercetin were mildly active against the parasites. Most of the potato peel samples were at least somewhat active against all three trichomonad species, but their activities were wide-ranging and did not correspond to their glycoalkaloid and phenolic content determined by HPLC. The two Russet samples were the most active against all three parasites. The purple potato peel sample was highly active against bovine and mostly inactive against feline trichomonads. None of the test substances were inhibitory toward several normal microflora species, suggesting the potential use of the peels for targeted therapeutic treatments against trichomonads.

Food Glycoalkaloids: Distribution, Structure, Cytotoxicity, Extraction, and Biological Activity

“…In a recent study, Friedman et al reported that the GAs α-chaconine and α-solanine were highly active against three pathogenic strains of trichomonads. These authors also reported that the activity of α-solanine was several times higher than α-chaconine; which is contrary to the several previous results where the influence of α-chaconine was reported higher than that of α-solanine [105]. Several other research works regarding the impact of potato glycoalkaloids on the membrane of frog embryos [106][107][108] and on fungi such as A. crenulatus, A. brassicicola, P. medicaginis, and R. solani [109,110] showed that α-chaconine was more active than α-solanine.…”

Light exposure and wounding: synergistic effects on steroidal glycoalkaloid accumulation in potato tubers during storage

“…These results suggest that the difference in SGA content between the light exposure and control groups originated from the skins, namely, light affected SGA accumulation in the skin and not in the flesh, for which further molecular and genetic evidence is required to elucidate the mechanism. The potential use of the tuber peels for targeted therapeutic treatments against pathogenic parasite such as trichomonads should be taken into account due to tuber peels are rich in bioactive compounds SGA (Friedman et al, 2018).…”

Potato Glycoalkaloids: occurrence, biological activities and extraction for biovalorisation – a review

“…Beside their toxicity and detrimental effects, numerous studies investigated the beneficial biological properties of glycoalkaloids such as antibiotic activities against bacteria, fungi, viruses and protozoa (Niño et al ., ; Friedman et al ., ; Lelario et al ., ). Additionally, numerous studies reported pharmaceutical activities of glycoalkaloids against many diseases and metabolic disorders such as inflammation, glycemia, allergies, fever and even certain types of cancers (Camire et al ., ; Patel et al ., ; Liu et al ., ; Friedman, ).…”