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Determination of the Juglone Content of Juglans regia Leaves by GC/MS.

Determination of the Juglone Content of Juglans regia Leaves by GC/MS.

Natural product communications (2015-09-29)

Irena Matławska, Wiesława Bylka, Ewa Widy-Tyszkiewicz, Beata Stanisz

ABSTRACT

The constituents of walnut (Juglans regia L.) leaves are represented by tannins, phenolics, and naphthoquinones, the characteristic compound being juglone. The content of juglone in the methanolic extract of the leaves determined by the GC/MS method was 9.9 ± 0.2 mg/100 g; small amounts (1.3 ± 0.02 mg/100 g) were recorded in the infusion, whereas in the decoction it was not detected. As some studies indicate toxicity of juglone, only decoctions should be recommended for therapeutic use.

MATERIALS

Product Number

Brand

Product Description

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Ethyl formate, reagent grade, 97%

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