514 Handbook of herbs and spices
31.7.5 Antioxidative properties
The kinetics of peroxide accumulation during oxidation of sunflower oil at 100^ ∞C in
the presence of different concentrations of hexane, ethyl acetate and ethanol extracts
of Melissa officinalis, Mentha piperita, M. spicata, Ocimum besilicum, Origanum
vulgare, and Saturejae hertensis were studied by Marinova and Yanishlieva (1997).
It has been established that the extracts from O. basilicum and Origanum vulgare do
not improve the oxidation stability of sunflower oil. The ethanol extracts from the
other four species including M. spicata have proved to be the most active in retarding
the auto-oxidation process for stabilization of sunflower oil.
31.7.6 Role in augmenting N-uptake of plants
Kiran and Patra (2002) conducted a field study to compare efficiency of Dicyandiamide
(DCD)-coated urea with some natural essential oils and their derivatives, viz., M.
spicata oil, dementholized oil (DMO) and terpenes-coated urea on wheat (Triticum
aestivum L.) yield, nitrogen (N) uptake and apparent N recovery on a sandy loam soil
of Central Uttar Pradesh, India, where excessive loss of N due to NO3 leaching is a
serious problem due to its light texture. A significant increase in grain and straw
yield, N-uptake and apparent N-recovery was observed on application of these
nitrification inhibitors. However, their performance varied with the percentage used;
it was higher with the higher level of application. All three natural coating materials
retarded nitrification significantly, throughout the growth period of wheat as compared
to materials at a 0.50% (V/W) level of coating on urea were 29.6%, 27.2% and 22.7%
with DMO, M. spicata oil and terpenes, respectively. Corresponding values at a
1.00% (V/W) level of coating were 4.0%, 38.6%, 23.2%, respectively. With DCD
coated urea (at a 1.00% level of coating, W/W basis) it was 33.1%, while the
corresponding value with uncoated urea was 22.7%.
Economic analyses were done for the use of these natural coating materials for
cultivation. Benefits obtained from the use of DMO, M. spicata oil and terpenes at a
0.50% level of coating were Rs. 5,210/ha, Rs. 1,400.00/ha and Rs. 450.00/ha,
respectively while at a 1.00% level of coating, corresponding profits were Rs. 9,040.00/
ha, Rs. 4,570.00/ha and 575.00/ha, respectively. The benefit obtained from the use of
DCD at a 1.00% level of coating was Rs. 1,005.00/ha.
31.7.7 Role as intercrop in pest management
The efficacy of intercropping cabbage with other vegetables and herbs including M.
Table 31.2 Comparative chemical composition (%) of Indian spearmint oil
produced from plants of the variety Arka, harvested after 100 days of plantingSr. no. Compounds Relative concentration (%)- Carvone 62.1
- Limonene 16.2
- 1,8 Cineole 2.0
- 3-octanol 0.4
- b-bourbonene 0.9
- b-Caryophyllene 0.9
- Sabinene hydrate 1.5
Data source: Bahl et al. 2000.