Ultra-High Performance Liquid Chromatography (UHPLC) Method for the Determination of Limonene in Sweet Orange (Citrus sinensis) Oil: Implications for Limonene Stability.

Ultra-High Performance Liquid Chromatography (UHPLC) Method for the Determination of Limonene in Sweet Orange (Citrus sinensis) Oil: Implications for Limonene Stability.

Journal of AOAC International (2015-04-11)

Matthew W Bernart

ABSTRACT

The citrus-derived bioactive monoterpene limonene is an important industrial commodity and fragrance constituent. An RP isocratic elution C18 ultra-HPLC (UHPLC) method using a superficially porous stationary phase and photodiode array (PDA) detector has been developed for determining the limonene content of sweet orange (Citrus sinensis) oil. The method is fast with a cycle time of 1.2 min, linear, precise, accurate, specific, and stability indicating, and it satisfies U.S. Pharmacopeia suitability parameters. The method may be useful in its present form for limonene processing, or modified for research on more polar compounds of the terpenome. A forced-degradation experiment showed that limonene is degraded by heat in hydro-ethanolic solution. PDA detection facilitates classification of minor components of the essential oil, including β-myrcene.

MATERIALS

Product Number

Brand

Product Description

09-0800

Sigma-Aldrich

Ethanol, JIS first grade, 94.8-95.8%

574724

Sigma-Aldrich

Acetonitrile solution, contains 0.05 % (v/v) trifluoroacetic acid

574732

Sigma-Aldrich

Acetonitrile solution, contains 0.1 % (v/v) trifluoroacetic acid, suitable for HPLC

685461

Sigma-Aldrich

Acetonitrile solution, contains 10.0% acetone, 0.05% formic acid, 40.0% 2-propanol

09-0790

Sigma-Aldrich

Ethanol, JIS special grade, 94.8-95.8%

48075

Supelco

Ethanol solution, certified reference material, 2000 μg/mL in methanol

576956

Sigma-Aldrich

Acetonitrile solution, contains 0.1 % (v/v) formic acid, suitable for HPLC

PHR1070

Supelco

Dehydrated Alcohol, Pharmaceutical Secondary Standard; Certified Reference Material

679186

Sigma-Aldrich

Acetonitrile solution, contains 0.05 % (w/v) ammonium formate, 5 % (v/v) water, 0.1 % (v/v) formic acid, suitable for HPLC

00590590

(R)-(+)-Limonene, primary reference standard

1012772

USP

Dehydrated Alcohol, United States Pharmacopeia (USP) Reference Standard

2858

Sigma-Aldrich

Ethanol Fixative 80% v/v, suitable for fixing solution (blood films)

17236

Sigma-Aldrich

3-(Benzyldimethylammonio)propanesulfonate, BioXtra, ≥99.0% (HPCE)

62122

Sigma-Aldrich

(R)-(+)-Limonene, technical, ~90% (sum of enantiomers, GC)

62118

Supelco

(R)-(+)-Limonene, analytical standard

183164

Sigma-Aldrich

(R)-(+)-Limonene, 97%

W263303

Sigma-Aldrich

(R)-(+)-Limonene, ≥93%

PHR1320

Supelco

Residual Solvent - Acetonitrile, Pharmaceutical Secondary Standard; Certified Reference Material

270717

Supelco

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459828

Sigma-Aldrich

Ethyl alcohol, Pure, 200 proof, HPLC/spectrophotometric grade

459844

Sigma-Aldrich

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493546

Sigma-Aldrich

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439134

Sigma-Aldrich

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34881

Sigma-Aldrich

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34998

Sigma-Aldrich

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02857

Sigma-Aldrich

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02870

Sigma-Aldrich

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02882

Sigma-Aldrich

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110086

Sigma-Aldrich

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E7023

Sigma-Aldrich

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