Supercritical Fluids

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I. ABSTRACT (ENGLISH)

The experimental determination of the yield of pyrethrins from the Chrysanthemum cinerariaefolium flower is usually carried out with Chromatographic Techniques. A lot of methods about this have been reported over the years [Z-M. ChertY.H. Wang (1996)]. These include HPLC [13 -22], GC [22-26] and SFC [B. Wenclawiak, A. Otterbach (2000) methods. Because of the need for only analyzing the pyrethrins (not reporting for the individual six pyrethrins but analyzing for total pyrethrins), GC was selected as a method of choice.

The yield reported from literature usually ranges from 0.91 – 1.30% of the dry weight [Kolak et al., 1999], 0.60 – 0.79% [Bakarić (2005)], 0.75 – 1.04% [Bhat (1995)],

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1.80 – 2.50% [Morris et al. (2005), Bhat and Menary, (1984); Fulton, (1999)], 0.50 – 2.0% [Kiriamiti et al. (2003)], and 0.90 – 1.50% [Pandita and Sharma (1990)].

However, Casida and Quistad (1995) in their book: Pyrethrum Flowers: Production, Chemistry, Toxicology and Uses (pp123-193), states that it is possible to obtain pyrethrin yield of 3.0% or even more.

We obtained, with hexane extraction in a water bath at controlled temperatures and vigorous stirring (with three magnetic stirrers at a speed of 30rpm); pyrethrin yields varying from 0.85 – 3.76% of the dry weight. To our knowledge, this is the first time to report of pyrethrins yield above 3% envisaged by Casida and Quistad.

Key words:

Supercritical Fluid Extraction, Supercritical Carbon Dioxide, Pyrethrins, Solvent extraction, Extraction Yield, Gas Chromatography, Pyrethrin concrete, Crude Hexane Extract.

III. ABBREVIATIONS AND SYMBOLS

GC Gas Chromatography

HPLC High Performance Liquid Chromatography

SFC Supercritical Fluid Chromatography

SCF Supercritical Fluid

SCFs Supercritical Fluids

SFE Supercritical Fluid Extraction

SC-CO2 Supercritical Carbon Dioxide

SC Supercritical

CO2 Carbon Dioxide

et al et alii (and others)

pp page

% percentage

CHE crude hexane extracts

BC Before Christ

PY pyrethrin

PYI pyrethrin 1

PYII pyrethrin 2

C1 cinerin 1

C2 cinerin 2

J1 Jasmolin 1

J2 Jasmolin 2

P1 pyrethrin 1

P2 Pyrethrin 2

A1 area of pyrethrins 1

A2 area of pyrethrins 2

WHO world health organization

Fig

Pc critical pressure

Tc critical Temperature

Cp critical point

Cm centimeters

~ Approximately

oC degree centigrade

MPa mega Pascal

FID flame ionization detector

n-hexane normal hexane

mL milliliters

/min per minute

Soc. Society

Eds editions

Sci.

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