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Oguh et al.; AJBGE, 2(3): 1-18, 2019; Article no.AJBGE.53356

an obligate fish parasite that is a big threat to the and is often used as a fish poison (piscicide) in
salmon population [12]. water management programs.

Rotenone are derived from the roots of over 68 Compound that disrupts energy metabolism has
plant species and is very toxic to fish, pigs, and been identified from both natural and synthetic
cool blooded animals. It is used to control leaf- sources. Complex I is inhibited by rotenone
eating caterpillars and beetles. Direct contact which is derived from cube or derris root.
may cause skin and mucous membranes Disruption of energy metabolism occurs in the
irritation. Rotenone is one of several mitochondria and usually takes the form of either
isoflavonoids produced in the roots. Extraction of an inhibition of the ETS, blockage of ATP
the root with organic solvents yields resins synthesis. The ETS (complexes i-iv are
containing as much as 45% total rotenoids; macromolecular complexes that use high energy
studies indicate that the major constituents are electrons to pump out hydrogen into the
rotenone (44%), and deguelin (22%) [22]. intermembrane space and to store this energy as
Rotenone is commonly sold as dust containing 1 a proton gradient, which is harnessed to
to 6% active ingredients for home and garden synthesize ATP. Inhibition of ETS blocks
use, but liquid formulations used in organic indirectly the production of ATP and cause a
agriculture can contain as much as 9% rotenone decrease in oxygen consumption by the
and 16% total rotenoids. mitochondria. Rotenone inhibit complex I in the
ETS and blockage at this site can reduce energy
Rotenone is a mitochondrial poison, which blocks production and induce whole animal toxicity. The
the electron transport chain and prevents energy disruption energy metabolism and the
production. As a pesticide, it is considered a subsequent loss of ATP results in a slowly
stomach poison because it must be ingested to developing toxicity, and the effects of all these
be effective. Pure rotenone is comparable to compounds include inactivity, paralysis, and
Dichloro-diphenyl-trichloroethane (DDT) and death [25] shown in Fig. 1.
other synthetic pesticides in terms of its acute
toxicity to mammals (rat oral LD50 is 132 mg 3.2 Nicotine
kg−1), although it is much less toxic at the levels Nicotine is an alkaloid obtained from the foliage
seen in formulated products. Safety of rotenone of tobacco plants (Nicotiana tabacum) and
has recently been called into question because related species, has a long history as an
of: Controversial reports that acute exposure in
insecticide. Nicotine (Fig. 2) and two closely
rats produces brain lesions consistent with those
observed in humans and animals with related alkaloids, nornicotine and anabasine, are
synaptic poisons that mimic the neurotransmitter
Parkinson’s disease [23]. And the persistence of acetylcholine. As such, they cause symptoms of
rotenone on food crops after treatment. A study poisoning similar to those seen with
of rotenone residues on olives conducted in Italy organophosphate and carbamate insecticides
determined that the half-life of rotenone is 4
days, and at harvest residue levels were above [13]. Owing to the extreme toxicity of pure
the tolerance limit [24]. Moreover, residues were nicotine to mammals (rat oral LD50 is 50 mg
kg−1) and its rapid dermal absorption in humans,
concentrated in oil obtained from the olives. As nicotine has seen declining use, primarily as a
an Agricultural pesticide, use of rotenone is fumigant in greenhouses against soft-bodied
limited to organic food production. pests. However, there remains some interest in
preparing stable nicotine fatty acid soaps,
3.1.1 Rotenone mode of action presumably with reduced bioavailability and
toxicity to humans [26]. Nicotine is a Pale yellow
Rotenone is an important insecticide extracted to dark brown liquid which is highly toxic to
from various leguminous plants. It inhibits the warm-blooded animals. Nicotine is a fast-acting
transfer of electrons from nicotine amide-adenine contact killer for soft bodies but does not kill most
(NADH) to ubiquinone. Rotenone is a powerful
inhibitor of cellular respiration, the process that chewing insects. Nicotine is highly lipophilic and
converts nutrient compounds into energy at the can pass through dermal tissues as well as the
blood brain barrier.
cellular level (Fig. 1). In insects rotenone exerts
its toxic effects primarily on nerve and muscle 3.2.1 Nicotine mode of action
cells, causing rapid cessation of feeding. Death
occurs several hours to a few days after In both insects and mammals, nicotine is an
exposure. Rotenone is extremely toxic to fish, extremely fast-acting nerve toxin. It competes

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