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Abstract
-----------------------------------ABSTRACT
ABSTRACT
F our Eucalyptus species as a source of natural antioxidant
were used named Eucalyptus camaldulensis (Sinai),
E.camaldulensis (valley), E.citriodora, and E.gomphocephala.
The defatted leaves were extracted with three different sui vents
named diethyl ether, chloroform and 80% ethanol. Different
concentrations (0.01 %, 0.02% and 0.03%) of the three extracts
of four Eucalyptus species were added individually to soybean
oil and compared with (0.02%) TBHQ. Samples were stored in a
thermostatically controlled oven at 60°C for 20 days.Samples
were periodically withdrawn every 2 days for the determination
of the PV, TBA value, oxygen electrode test, refractive index,
antioxidant effectiveness, and GLC analysis.
The important obtained results could be summarized as follow.
All of treated soybean oil with 0.03% concentration of ethanol
extracts of E. gomphocephala and E. camaldulensis (Sinai) was
more stable than 0.02% TBHQ. The concentration of 0.03%
ethanol extract of all plants was more effective as antioxidant
agent than other two solvents, (0.03%ether and-
0.03%chloroform). The antioxidant effectiveness of each extract
of the four Eucalyptus species in comparison with TBHQ was
fllowing the order E. gomphocephala >E. camaldulensis (Sinai»
TBHQ> E. camaldulensis (valley» E. cetriodora. GC-MS
analysis of ethanol extract of E.camaldulensis (Sinai) indicated
that there are 12 components in the sample and GC-MS analysis
of ethanol extract of E.gomphocephala indicated that there are 14
components in the sample a-pinene, p-cymene, Aromadendrene,
lemonene , Allo Aromadendrene , a-terpineol, Benzene-l-ethyl
2, 4 dimethyl, Methyleugenol , Trans-pinocarveol , 1,8 cineol,
crypton , spathulenol, and carvone . could be responsible for the
antioxidant effectiveness
~
-----------------------------------ABSTRACT
ABSTRACT
F our Eucalyptus species as a source of natural antioxidant
were used named Eucalyptus camaldulensis (Sinai),
E.camaldulensis (valley), E.citriodora, and E.gomphocephala.
The defatted leaves were extracted with three different sui vents
named diethyl ether, chloroform and 80% ethanol. Different
concentrations (0.01 %, 0.02% and 0.03%) of the three extracts
of four Eucalyptus species were added individually to soybean
oil and compared with (0.02%) TBHQ. Samples were stored in a
thermostatically controlled oven at 60°C for 20 days.Samples
were periodically withdrawn every 2 days for the determination
of the PV, TBA value, oxygen electrode test, refractive index,
antioxidant effectiveness, and GLC analysis.
The important obtained results could be summarized as follow.
All of treated soybean oil with 0.03% concentration of ethanol
extracts of E. gomphocephala and E. camaldulensis (Sinai) was
more stable than 0.02% TBHQ. The concentration of 0.03%
ethanol extract of all plants was more effective as antioxidant
agent than other two solvents, (0.03%ether and-
0.03%chloroform). The antioxidant effectiveness of each extract
of the four Eucalyptus species in comparison with TBHQ was
fllowing the order E. gomphocephala >E. camaldulensis (Sinai»
TBHQ> E. camaldulensis (valley» E. cetriodora. GC-MS
analysis of ethanol extract of E.camaldulensis (Sinai) indicated
that there are 12 components in the sample and GC-MS analysis
of ethanol extract of E.gomphocephala indicated that there are 14
components in the sample a-pinene, p-cymene, Aromadendrene,
lemonene , Allo Aromadendrene , a-terpineol, Benzene-l-ethyl
2, 4 dimethyl, Methyleugenol , Trans-pinocarveol , 1,8 cineol,
crypton , spathulenol, and carvone . could be responsible for the
antioxidant effectiveness
~