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

00590590

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

PHR1551

Supelco

Acetonitrile(Neat), Pharmaceutical Secondary Standard; Certified Reference Material

PHR1320

Supelco

Residual Solvent - Acetonitrile(solution in DMSO), Pharmaceutical Secondary Standard; Certified Reference Material

E7148

Sigma-Aldrich

Ethyl alcohol, Pure 190 proof, for molecular biology

24106

Sigma-Aldrich

Ethanol, puriss., meets analytical specification of Ph. Eur., BP, 96 % (v/v)

2858

Sigma-Aldrich

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

62118

Supelco

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

62122

Sigma-Aldrich

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

183164

Sigma-Aldrich

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

17236

Sigma-Aldrich

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

PHR1070

Supelco

Dehydrated Alcohol, Pharmaceutical Secondary Standard; Certified Reference Material

60004

Sigma-Aldrich

Acetonitrile, ≥99.5% (GC)

792799

Sigma-Aldrich

Ethyl alcohol, Pure, 190 proof, ACS reagent, meets USP testing specifications, Excise Tax-free, Permit for use required

02856

Sigma-Aldrich

Ethanol, purum, absolute ethanol, denaturated with 4.8% isopropanol, A15 IPA¹, ≥99.8% (based on denaturant-free substance)

110086

Sigma-Aldrich

Acetonitrile, ReagentPlus^®, 99%

02857

Sigma-Aldrich

Ethanol, purum, fine spirit, denaturated with 4.8% methanol, F25 METHYL¹, ~96% (based on denaturant-free substance)

02858

Sigma-Aldrich

Ethanol, purum, absolute ethanol, denaturated with 1% cyclohexane, A15 CYCLO¹, ≥99.8% (based on denaturant-free substance)

02870

Sigma-Aldrich

Ethanol, ACS reagent, prima fine spirit, without additive, F15 o¹

02882

Sigma-Aldrich

Ethanol, purum, absolute ethanol, denaturated with 2% 2-butanone, A15 MEK¹, ≥99.8% (based on denaturant-free substance)

02890

Sigma-Aldrich

Ethanol, purum, fine spirit, denaturated with 2% 2-butanone, F25 MEK¹, ~96% (based on denaturant-free substance)

E7023

Sigma-Aldrich

Ethyl alcohol, Pure 200 proof, for molecular biology

459828

Sigma-Aldrich

Ethyl alcohol, Pure, 200 proof

32205

Sigma-Aldrich

Ethanol, absolute, reag. ISO, reag. Ph. Eur., ≥99.8% (GC), liquid (clear, colorless)

32221

Sigma-Aldrich

Ethanol, puriss. p.a., absolute, ≥99.8% (GC)

33019

Sigma-Aldrich

Acetonitrile, puriss. p.a., ACS reagent, reag. Ph. Eur., ≥99.5% (GC)

493546

Sigma-Aldrich

Ethyl alcohol, Pure, 200 proof, meets USP testing specifications

459844

Sigma-Aldrich

Ethyl alcohol, Pure, 200 proof, ACS reagent, ≥99.5%

494445

Sigma-Aldrich

Acetonitrile, biotech. grade, ≥99.93%

360457

Sigma-Aldrich

Acetonitrile, ACS reagent, ≥99.5%

34442

Sigma-Aldrich

Acetonitrile, suitable for DNA synthesis, ≥99.9% (GC)