Efficacy and Safety of Fig (Ficus carica L.) Leaf Tea in Adults with Mild Atopic Dermatitis: A Double-Blind, Randomized, Placebo-Controlled Preliminary Trial.

Atopic dermatitis (AD) is a chronic, recurrent pruritic skin disease with repeated remissions and exacerbations. Various factors, such as allergies, skin conditions and lifestyle, combine to cause AD, making it difficult to cure completely. Although AD symptoms are suppressed with medications, this is a long-term effort and burden on patients. Thus, safer drugs and alternatives are needed. We previously found that consumption of tea prepared from fig (Ficus carica L.) leaves alleviated allergy and AD symptoms in cultured cells and animals. Therefore, here, we conducted a double-blind, randomized, controlled study in patients with mild AD to evaluate the safety and AD-relieving effects of prolonged consumption of fig leaf tea. Positive effects of fig leaf tea consumption were confirmed in 14 of 15 participants. Eczema Area and Severity Index values were significantly lowered in the fig leaf tea-treated group than in the placebo-treated group. The effect weakened 4 weeks after the end of the intervention, suggesting that continued intake of fig leaf tea was effective. Further assessments confirmed the safety of fig leaf tea consumption and revealed no variations that might pose a health hazard. Therefore, we postulate that fig leaf tea is a natural and safe therapeutic option for AD.

Phenylpropanoid composition in fig (Ficus carica L.) leaves.

The leaves of fig (Ficus carica L.) have been used for traditional and Chinese medicine. We determined the composition of phenylpropanoids (polyphenols and furanocoumarins) as a functional agent in the leaves of 37 cultivars of fig. The most abundant polyphenol was caffeoylmalic acid (12.0-26.6 mg/g dry weight), followed by rutin (4.7-14.6 mg/g dry weight) and isoschaftoside (2.5-6.4 mg/g dry weight). Psoralen (3.8-23.0 mg/g dry weight) was dominant in the furanocoumarins. In molar amounts, psoralic acid glucoside (PAG), a precursor of psoralen, was equivalent to psoralen. Furanocoumarins and PAG were not detected in the leaves of only one cultivar, Grise de Tarascon. Fig leaves are potentially an excellent source of polyphenols such as caffeoylmalic acid and rutin. From the result of cluster analysis, some cultivars that contained large amount of polyphenols, and a small amount (e.g., Grise de Saint Jean) or no (Grise de Tarascon) furanocoumarins, were found. These cultivars are considered suitable for functional foods or medicinal products.

Identification of phenylpropanoids in fig (Ficus carica L.) leaves.

In this study, the phenylpropanoid composition and antioxidant activity of identified components in fig (Ficus carica L.) leaves were examined. Known polyphenols rutin, isoschaftoside, isoquercetin, and chlorogenic acid were identified. Furthermore, caffeoylmalic acid (CMA) was the most abundant polyphenol and was identified for the first time. CMA exhibited antioxidant activity similar to that of vitamin C or catechin. Psoralen and bergapten were identified as known furanocoumarins, with psoralen being the most abundant. Moreover, psoralic acid glucoside (PAG) was identified for the first time. As a precursor of psoralen, PAG content was equivalent to the psoralen content in moles. Notably, the content of these compounds varied between the five fig varieties, and the furanocoumarin and PAG contents varied more than that of the polyphenols. Further investigations concerning the influence of CMA and PAG on human health are necessary to elucidate functionalities of fig leaves.