The in vitro antioxidant properties ofMuscari comosumbulbs and their inhibitory activity on enzymes involved in inflammation, post-prandial hyperglycemia, and cognitive/neuromuscular functions

Abstract

Extracts of Muscari comosum bulbs, a traditional Mediterranean food, were analyzed by high performance liquid chromatography for polyphenol content and tested for their activity on free‐radicals and enzymes that might be involved in human health. The extracts revealed the presence of phenolic acids and flavonoids with antioxidant and anti‐inflammatory properties. Antioxidant activity was determined by evaluating the radical scavenging activity toward 2,2‐diphenyl‐1‐picrylhydraziyl (DPPH˙), nitric oxide (˙NO), and superoxide (O2˙−), whereas the anti‐inflammatory activity was determined by zymography by evaluating the in‐gel inhibition of MMP‐9 and MMP‐2, two pro‐inflammatory gelatinases. Anti‐glycemic activity was determined by measuring the inhibition of α‐amylase and α‐glucosidase, two enzymes involved in post‐prandial hyperglycemia. Finally, M. comosum extracts were found to inhibit the enzyme acetylcholine esterase. The resulting increase of acetylcholine availability might improve cognitive functions and neuromuscular transmission. Our laboratory findings substantiate and extend previous results, but the clinical value of M. comosum properties needs to be further evaluated. Practical applications Muscari comosum bulbs are mostly used in a few Mediterranean countries and in particular in Southern Italy, where they are commonly known as “lampascioni” or “cipollacci.” The most popular recipe in traditional gastronomy. consists in boiling the cleaned bulbs and keep them in olive oil. The present study shows that M. comosum bulbs have a strong antioxidant and anti‐inflammatory activity in vitro, and inhibit specific enzymes involved in hyperglycemia or cholinergic neurotransmission. The above properties might be useful in diabetic individuals to reduce post‐prandial hyperglycemia and might improve acetylcholine transmission and therefore cognitive and neuromuscular functions.

Muscari comosum L. Bulb Extracts Modulate Oxidative Stress and Redox Signaling in HepG2 Cells

“…Total phenolic and flavonoid contents found in this study are more similar with those reported by Loizzo et al (2010) [ 13 ] and with those reported in our previous work for the aqueous methanolic bulb extract [ 16 ]. As reported by several authors [ 19 , 20 ], the amount of phenolic compounds represents an important indicator of antioxidant capacity.…”

“…MET70 had the highest amounts of total polyphenols and flavonoids and demonstrated the best radical scavenging activity vs. DPPH and O 2 − . In a previous study [ 16 ], twelve different compounds were identified in the HPLC profile of 70% methanol extract of M. comosum bulbs, seven of them were phenolic acids (gallic, vanillic, chlorogenic, caffeic, syringic, p -coumaric acid and ferulic) and five were flavonoids (catechin, epicatechin, rutin, naringenin and kaempferol).…”

“…The capacity of the bulb extracts to scavenge 2,2-diphenyl-1-picrylhydraziyl (DPPH˙) radical was evaluated as previously reported [ 16 ]. Briefly, 0.5 mL of the extracts were added to 0.5 mL of 0.2 mM DPPH˙ in methanol, and incubated at room temperature for 30 min in the dark.…”

“…Recent studies show that the homoisoflavanones contained in this plant, interacting with the estrogenic receptors, may have a potential role as hormone substitutes or useful supplements for the treatment of hormone-sensitive tumours [ 15 ]. Recently, it has also been shown that the extract of Muscari comosum has potential antioxidant and hypoglycaemic activity due to its inhibitory activity on α-amylase and α-glucosidase [ 16 ].…”

Mineral Content, Chemical Analysis, In Vitro Antidiabetic and Antioxidant Activities, and Antibacterial Power of Aqueous and Organic Extracts of Moroccan Leopoldia comosa (L.) Parl. Bulbs

“…In comparison with other work carried out on L. comosa bulbs, the study carried out by Larocca et al in Italy reported a yield of 7.61 ± 0.10% for the extract prepared by the hydroalcoholic solvent (water/methanol 70%) by maceration using centrifugation of 80 rpm (rotation per minute) for 24 hours at 30°C [33]. Another study conducted by Loizzo et al [34] in Italy on L. comosa bulbs showed that the yield was 3.16% for the ethanolic extract prepared by maceration for 48 hours compared to 1.3% for the macerated ethanolic extract of Moroccan L. comosa bulbs.…”