categorized into four major types namely carbohydrates and lipids, alkaloids and
other nitrogen containing metabolites, phenolic compounds, and terpenoids
(Table 8.4) (Baxter et al. 1998). The bioactive compounds present in the
phytochemicals are responsible for ovicidal, larvicidal, reduced progeny emergence,
toxicity, and repellency. Phytochemicals can be extracted using different methods
viz., solvent extraction, microwave assisted extraction, ultrasonic assisted extraction,
and can be utilized for pest management (Altemimi et al. 2017).
8.3
Extraction Methods
Pre-extraction and the extraction procedures are important in processing bioactive
constituents from plant materials. Traditional methods such as maceration and
Soxhlet extraction using solvents are commonly used. Solvent preparation, solvent
sample ratio, extraction procedures, and methods for extraction are to be considered
when separating the compound of interest.
8.3.1 Solvent Extraction Method
The basic step for initiating solvent extraction is drying of the plant either through
sun drying or hot air oven. This step is followed by pulverisation of the plant. It can
be performed using mechanical means like mortar and pestle or a mixer. Other
techniques that can be used are enzymatic degradation and chemical degradation.
This helps in homogenisation with the solvent by allowing the solvent to penetrate
the ruptured walls overnight at chilled condition (4
C). Then it is filtered on the next
day using muslin cloth or filter paper followed by evaporation of the solvent using
Table 8.2 Bioactive compounds in plants
Plant
Bioactive compounds
References
Cymbopogon citratus
Citral
Anggraeni et al. (2018)
Allium sativum
Diallyl disulphide and diallyl
sulphide
Plata-Rueda et al. (2017)
Carica papaya
Oleic acid
Ghosh et al. (2017)
Curcuma longa
Curcumin
Gul and Basheer (2016)
Acorus calamus
α and β-asarone
Devi et al. (2014)
Cinnamomum
aromaticum
Cinnamaldehyde
Wong et al. (2014)
Andrographis
paniculata
Andrographolide
Chao et al. (2009)
Ocimum basilicum
Estragole
López et al. (2008)
Azadirachta indica
Azadirachtin
Sadeghian and Mortazaienezhad
(2007)
Mentha spicata
Carvone
Tripathi et al. (2000)
Citrus sinensis
d-limonene
Karr and Coats (1988)
8 Phytochemicals for the Management of Stored Product Insects
173
other nitrogen containing metabolites, phenolic compounds, and terpenoids
(Table 8.4) (Baxter et al. 1998). The bioactive compounds present in the
phytochemicals are responsible for ovicidal, larvicidal, reduced progeny emergence,
toxicity, and repellency. Phytochemicals can be extracted using different methods
viz., solvent extraction, microwave assisted extraction, ultrasonic assisted extraction,
and can be utilized for pest management (Altemimi et al. 2017).
8.3
Extraction Methods
Pre-extraction and the extraction procedures are important in processing bioactive
constituents from plant materials. Traditional methods such as maceration and
Soxhlet extraction using solvents are commonly used. Solvent preparation, solvent
sample ratio, extraction procedures, and methods for extraction are to be considered
when separating the compound of interest.
8.3.1 Solvent Extraction Method
The basic step for initiating solvent extraction is drying of the plant either through
sun drying or hot air oven. This step is followed by pulverisation of the plant. It can
be performed using mechanical means like mortar and pestle or a mixer. Other
techniques that can be used are enzymatic degradation and chemical degradation.
This helps in homogenisation with the solvent by allowing the solvent to penetrate
the ruptured walls overnight at chilled condition (4
C). Then it is filtered on the next
day using muslin cloth or filter paper followed by evaporation of the solvent using
Table 8.2 Bioactive compounds in plants
Plant
Bioactive compounds
References
Cymbopogon citratus
Citral
Anggraeni et al. (2018)
Allium sativum
Diallyl disulphide and diallyl
sulphide
Plata-Rueda et al. (2017)
Carica papaya
Oleic acid
Ghosh et al. (2017)
Curcuma longa
Curcumin
Gul and Basheer (2016)
Acorus calamus
α and β-asarone
Devi et al. (2014)
Cinnamomum
aromaticum
Cinnamaldehyde
Wong et al. (2014)
Andrographis
paniculata
Andrographolide
Chao et al. (2009)
Ocimum basilicum
Estragole
López et al. (2008)
Azadirachta indica
Azadirachtin
Sadeghian and Mortazaienezhad
(2007)
Mentha spicata
Carvone
Tripathi et al. (2000)
Citrus sinensis
d-limonene
Karr and Coats (1988)
8 Phytochemicals for the Management of Stored Product Insects
173