Re: Review of Therapeutic Uses and Antioxidant Content of Melissa officinalis

PDF (Download) Lemon Balm (Melissa officinalis, Lamiaceae) Antioxidant Date: 08-31-2017 HC# 021744-575 Miraj S, Rafieian-Kopaei M, Kiani S. Melissa officinalis L: a review study with an antioxidant prospective. J Evid Based Complementary Altern Med. 2017;22(3):385-394. Lemon balm (Melissa officinalis, Lamiaceae) has a rich history of traditional use and is easy to grow, making it economically appealing for cultivation. The goal of this review was to provide an overview of lemon balm's growth conditions, chemical compounds, and traditional uses, with a particular focus on its antioxidant properties. Lemon balm, a perennial native to southern Europe, is now naturalized worldwide. Occurring naturally in sandy scrublands, it will also grow in damp areas and at elevations from sea level to mountainous. It is easy to cultivate and spreads readily, making it ideal for beginning gardeners. Lemon balm is traditionally used for its sedative, tranquilizing, anti-gas, anti-fever, antibacterial, antioxidant, antiviral, antifungal, antiparasitic, spasmolytic, anti-inflammatory, memory-enhancing, menses-inducing, hypotensive, and thyroid-related effects. It is used for pain, indigestion, colic, nausea, amenorrhea, cardiac failure, arrhythmias, ulcers, wounds, headache, asthma, bronchitis, insomnia, epilepsy, and mental illnesses. The chemical compounds found in the leaf include flavonoids, polyphenols, monoterpenoid aldehydes, monoterpene glycosides, sesquiterpenes, tannins, and essential oils. Thirty-three compounds in total were identified, making up 89.3% of the total leaf oil. Six compounds predominated—citronellal (14.4%), isogeraniol (6.4%), geraniol acetate (10.2%), nerol acetate (5.1%), caryophyllene (8.1%), and caryophyllene oxide (11%). Composition of lemon balm leaf, essential oil (LBEO), dried leaves, and leaf extract varies, and as with all natural herbal products, may differ with habitat, growth conditions, harvest time, processing method, and storage time and conditions. Lemon balm exerts antimicrobial, spasmolytic, and sleep-promoting effects. Its viricidal and antiviral effects against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) have been investigated. Even very low concentrations of lemon balm extract have been found effective against HSV-1 in its early stages. A hydroalcoholic extract tried against HSV-2 in comparison to acyclovir had favorable results. Lemon balm's cinnamic acid-like compounds, especially rosmarinic acid, were most effective against both viruses. A "standardized balm mint cream" also tested favorably against HSV-1. LBEO was highly active against five human pathogenic bacteria, Candida albicans, and two phytopathogenic fungi in one study. It is active against a multidrug-resistant strain of Shigella sonnei bacteria and against Trichophyton spp. fungus. Gram-negative bacteria are not affected by LBEO. Rosmarinic acid contributes to lemon balm's antiviral, anti-inflammatory, and pain-relieving effects. An ethanolic extract produced dose-related antinociceptive effects in models of chemical pain through muscarinic and nicotinic acetylcholine receptors and the L-arginine-nitric oxide pathway. Colic in breast-fed infants decreased after one week of being given lemon balm. In vivo, the relaxing effect of LBEO and its main component, citral, inhibited rat-isolated ileum contractions in a concentration-dependent manner. In children with restlessness and nervous dyskoimesis (a form of dyssomnia), a valerian (Valeriana officinalis, Caprifoliaceae) and lemon balm preparation, Euvegal® forte (Dr. Willmar Schwabe GmbH & Co. KG; Karlsruhe, Germany), was well tolerated and effective in an open, multi-center study, demonstrating that chronic use of lemon balm relieves stress-related effects. Oxidative stress is implicated in the etiology and progression of several degenerative diseases via DNA mutation, protein oxidation, and/or lipid peroxidation. LBEO is a rich source of antioxidants, particularly phenolic compounds. Its activity is comparable to that of synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), largely due to the phenolics citronellal and neral (citral B). Essential oils, ethanolic extracts, and decoctions of 10 plant species from Portugal were compared for their activity toward acetylcholinesterase enzyme antioxidant activity. Essential oil fractions of both lemon balm and apple mint (Mentha suaveolens, Lamiaceae) exhibited acetylcholinesterase inhibitory capacity greater than 50%. Lemon balm shows appreciable antioxidant activity only in the polar fractions. The ethyl acetate fraction had the most flavonoid content and highest antioxidant activity compared with other fractions from lemon balm extract. Lemon balm scavenges both synthetic and natural free radicals, with high ability to scavenge, e.g., DPPH (2,2-diphenyl-1-picrylhydrazyl) in a concentration-dependent manner. Water extracts of lemon balm dose-dependently suppressed formation of DPPH, hydroxyl, and lipid peroxyl radicals. Many studies confirm lemon balm's radical scavenging effects and high levels of phenolics in various extracts and forms. In a study of phenolic profiles of lemon balm samples, including garden-cultivated, in vitro-cultured, and commercial ("bags and granulated"), the commercial products had higher phenolic content than garden-grown or in vitro-cultured samples (details not provided). The "bag" sample had the highest antioxidant potential. Rosmarinic acid is credited with much of lemon balm's antioxidant activity. In vivo studies confirm lemon balm's antioxidant effects in mice and in boars. In a clinical trial, a lemon balm infusion caused marked improvement in oxidative stress markers and DNA damage in radiology staff. Besides its free radical scavenging properties, lemon balm has iron(II)-chelating ability, and may inhibit formation of chemical reactive species that could contribute to lipid peroxidation. Flavonoids and benzodioxole are also credited with contributing to lemon balm's antioxidant activity. These compounds, along with rosmarinic acid, have been found to have antioxidant activity 10 times stronger than that of vitamins B and C. The authors point out that the ability of antioxidant supplements to prevent disease has not been confirmed with randomized clinical trials. Despite the prominence of rosmarinic acid in lemon balm's effects, rosmarinic acid alone might well produce conflicting results. The authors conclude by encouraging further studies on lemon balm's anti-inflammatory effects and the mechanisms of action of phenolics. —Mariann Garner-Wizard