Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro

Abstract

Protein glycation involves formation of early (Amadori) and late advanced glycation endproducts (AGEs) together with free radicals via autoxidation of glucose and Amadori products. Glycation and increased free radical activity underlie the pathogenesis of diabetic complications. This study investigated whether aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro in a cell-free system. Proteins were glycated by incubation with sugars (glucose, methylglyoxal or ribose) ±5–15 mg/mL of aged and fresh garlic extracts. Advanced glycation endproducts were measured using SDS-PAGE gels and by ELISA whereas Amadori products were assessed by the fructosamine method. Colorimetric methods were used to assess antioxidant activity, free radical scavenging capacity, protein-bound carbonyl groups, thiol groups and metal chelation activities in addition to phenolic, total flavonoid and flavonol content of aged and fresh garlic extracts. Aged garlic inhibited AGEs by 56.4% compared to 33.5% for an equivalent concentration of fresh garlic extract. Similarly, aged garlic had a higher total phenolic content (129 ± 1.8 mg/g) compared to fresh garlic extract (56 ± 1.2 mg/g). Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract and is more suitable for use in future in vivo studies.

Role of Garlic and Ginger in Anti-oxidative and Anti-inflammatory Effects in Aging

“…Garlic contains higher concentration of volatile sulfur compounds like thiosulfates, which gives pungent aroma and responsible for beneficial effects [4,5]. Garlic consist of 65% water, 28% carbohydrate (fructans), 2.3% organosulfur compounds, 2% proteins (allinase), 1.2% free amino acid (arginine) and 1.5% fiber [21].…”

“…It has been used to cure common cold, treat ailments ranging from cardiovascular diseases to cancer and heal infections, even the plague. Garlic constitutes rich contents of volatile sulfur compounds like thiosulfates, which provide pungent aroma and give beneficial effects [4,5]. Scientific research indicates that kyolic (aged garlic extract) is highly rich in antioxidants [6,7], better than fresh gar-lic, without causing stomach allergy.…”

Phytochemical profiling, polyphenol composition, and antioxidant activity of the leaf extract from the medicinal halophyteThespesia populneareveal a potential source of bioactive compounds and nutraceuticals

“…Free radicals are the major factors responsible for causing many diseases including cardiovascular disease, cancer, neural disorders, ulcerative colitis, and atherosclerosis (Elosta, Slevin, Rahman, & Ahmed, 2017). The previous studies suggest that the intake of dietary antioxidants can protect our system from damage caused by free radicals (Souli et al, 2018).…”

Capability of polygonum cuspidatum extract in inhibiting AGEs and preventing diabetes

“…Thus, during the reaction, the radicals also participate in accelerating the protein glycation by oxidizing side chains of amino acid residues of protein (Suantawee et al, ). It further leads to the formation of protein‐bound carbonyl or the loss of protein thiol group which causes protein oxidative damage (Elosta, Slevin, Rahman, & Ahmed, ). As a result, free radicals scavenging ability would be important for antiglycation purpose, especially at the early stages of glycation.…”

“…LG-B Slevin, Rahman, & Ahmed, 2017). As a result, free radicals scavenging ability would be important for antiglycation purpose, especially at the early stages of glycation.…”