Annona Species Monograph.pdf - Crops for the Future

Chapter 6. Properties
1997). The most important acetogenins are anonins or anonacins: asimicin,
annonastatin, bullatacin, bullatacinone and squamocin. These substances
have toxic effects when eaten by insects and can inhibit insect growth,
development and reproduction. The cytotoxic anonins cause 70% mortality
of Aedes aegypti with a concentration of only 10 ppm. They act by inhibiting
respiration (Londershausen et al., 1991 a, b). Asimicin is effective against
insect pests, such as A. aegypti, A. vittatum, A. gossypii, Colliphora vicina,
Epilachna varivertis, Tetranychus urticae, and the nematode Caenoharbiditis
elegans. This compound has 256 known isomers, of which bullatacin is the
most toxic (Li et al., 1990). Bullatacin causes 80% mortality of A. aegypti, A.
gossypii and Diabrotica undecimpunctata when in concentrations of 1, 10 or
24 ppm, respectively. Another powerful isomer is bullatacinone (Hernández
and Angel, 1997). Some of these acetogenins could be used as insect
repellents (Hernández and Angel, 1997).
6.2 Pulp properties
Annona pulps are useful foods because they contain proteins, fatty acids,
fibre, carbohydrates, minerals and vitamins (Bueso, 1980; Leal, 1990; Lizana
and Reginato, 1990). However, annona fruits do not contribute many calories
to the diet (Kalil et al., 1979).
Nutrients in the diet are important because they have many biological
functions, such as providing energy and matter for growth, and regulating
biological reactions. These functions are modulated by the quality and
quantity of the carbohydrates, lipids, proteins, minerals and vitamins in food.
Nutrients are divided into protectors and non-protectors. Protector nutrients
are essential to protect organisms against pathogens, while non-protector
nutrients provide only calories. Milk, meat and egg (principally because they
are rich in proteins), and vegetables and fruits (mainly because they are rich
in minerals and vitamins) are examples of foods that provide protector
nutrients (Evangelista, 1992).
The most important factors for a healthy diet are: (1) nutrients must be
ingested in sufficient quantity and quality to provide nutritional and caloric
balance. Sex, age and physical activity effect requirements for nutrients. For
example, a 65 kg person, with strong physical activity, needs 4,000 kcal/day
in the diet, while a person with strong intellectual activity needs only 3,000
kcal/day. (2) The balanced diet must provide a harmonious combination of
proteins, carbohydrates, lipids, minerals and vitamins. For example, a normal
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