potential plants as biopesticides has emerged as a result of the drawbacks associated
with the use of synthetic chemical methods notably among them are their high cost,
their carcinogenicity, teratogenicity, high and acute residual toxicity, long degradation period, environmental pollution and possible side-effects on human health
through the food chain (Ai-ying et al. 2011). These drawbacks coupled with public
concern have increased interest in developing further alternative control methods,
particularly those that are eco-friendly, biodegradable, feasible to the farmers,
non-toxic to human and animals, specific in their action and have a broad spectrum
of antimicrobial activity (Marino and Bersani 2001; Abhishek et al. 2013).
Scientific investigations on different morphological parts of medicinal plants
indicated the presence of biologically active compounds which possesses an array
of antimicrobial properties acting on different types of microorganisms. These
bioactive compounds were evaluated in vitro and further subjected to in vivo testing
to validate their efficacy in controlling the incidence and severity of diseases in
crops and insect infestations. Recently, Batista et al. (2014) reported the antifungal
inhibitory activity of Moringa-Chitin Binding Protein (Mo-CBP 3 ) purified from the
seeds of M. oleifera Lam. against mycelial growth and spore germination of
Fusarium solani at 0.05 mg mL
−1 . Similarly, in another study, Gifoni et al. (2012)
also showed the antifungal efficacy of Mo-CBP 3 chitin-binding protein purified also
from M. oleifera seed against phyopathogenic fungi Fusarium oxysporium, F.
solani, Colletotrichum gloesporiodes and Pythium oligandrum at 0.05 mg mL
−1
and 0.1 mg mL
−1 respectively. Dwivedi and Enespa (2012) reported that M. oleifera extracts (leaves, bark and seeds) at 75% (v/v) give significant inhibitory effect
on the mycelial growth of F. solani and Fusarium oxysporum f. sp. Lycopersici.
The fungicidal effect of Moringa extracts on some soil-borne fungi such as
Rhizoctonia, Pythium and Fusarium causing tomato rots was also reported (Moyo
et al. 2012). Again, El-Mohamedy and Abdalla (2014) reported the fungicidal effect
of M. oleifera against F. oxysporm, F. solani, Alternaria alternate, A. solani.
Rhizoctonia solani, Sclerotium rolfsii and Macrophomina phaseolina causing rots
on fruit and other perishables. Ukeh and Chiejina (2012) reported that phytopesticides from two plants including Afromomium meleguata and Zingiber officinale
inhibited Penicillium digitatum, Mucor piriformis, Aspergillus niger and
Heminsthoporium solani causal agents involved with soft rot of tomato. Ijato et al.
(2011) reported the antimicrobial activity of Vernonia amygdalina and Tridax
procumbens each with two varying formulations and concentrations (aqueous
extracts: 80 and 60% and ethanol extracts: 30 and 20%) against A. niger, F.
oxysporum, G. candidum and Rhizopus stolonifer. Again, the aqueous and organic
solvents (water and ethanol) extracts from leaves of Chromolaena odorantum and
Azachirachta indica were reported to have antifungal activity against fungal
pathogens that cause tomato rots (A. niger, F. oxysporum, R. stolonifer and G.
candidium) by poisoned food method (Ijato et al. 2011).They showed that among
the various extracts with varying concentrations, ethanol extracts of 30% A. indica
had the best inhibitory effect (83.30%) against A. niger followed by 30% ethanol
extract of C. odorata (80.00%) against G. candidium which proved the potentiality
of the plant extracts for the control of postharvest and transit fungal rot of tomato
2 An Introduction to Bioactive Natural Products …
73
with the use of synthetic chemical methods notably among them are their high cost,
their carcinogenicity, teratogenicity, high and acute residual toxicity, long degradation period, environmental pollution and possible side-effects on human health
through the food chain (Ai-ying et al. 2011). These drawbacks coupled with public
concern have increased interest in developing further alternative control methods,
particularly those that are eco-friendly, biodegradable, feasible to the farmers,
non-toxic to human and animals, specific in their action and have a broad spectrum
of antimicrobial activity (Marino and Bersani 2001; Abhishek et al. 2013).
Scientific investigations on different morphological parts of medicinal plants
indicated the presence of biologically active compounds which possesses an array
of antimicrobial properties acting on different types of microorganisms. These
bioactive compounds were evaluated in vitro and further subjected to in vivo testing
to validate their efficacy in controlling the incidence and severity of diseases in
crops and insect infestations. Recently, Batista et al. (2014) reported the antifungal
inhibitory activity of Moringa-Chitin Binding Protein (Mo-CBP 3 ) purified from the
seeds of M. oleifera Lam. against mycelial growth and spore germination of
Fusarium solani at 0.05 mg mL
−1 . Similarly, in another study, Gifoni et al. (2012)
also showed the antifungal efficacy of Mo-CBP 3 chitin-binding protein purified also
from M. oleifera seed against phyopathogenic fungi Fusarium oxysporium, F.
solani, Colletotrichum gloesporiodes and Pythium oligandrum at 0.05 mg mL
−1
and 0.1 mg mL
−1 respectively. Dwivedi and Enespa (2012) reported that M. oleifera extracts (leaves, bark and seeds) at 75% (v/v) give significant inhibitory effect
on the mycelial growth of F. solani and Fusarium oxysporum f. sp. Lycopersici.
The fungicidal effect of Moringa extracts on some soil-borne fungi such as
Rhizoctonia, Pythium and Fusarium causing tomato rots was also reported (Moyo
et al. 2012). Again, El-Mohamedy and Abdalla (2014) reported the fungicidal effect
of M. oleifera against F. oxysporm, F. solani, Alternaria alternate, A. solani.
Rhizoctonia solani, Sclerotium rolfsii and Macrophomina phaseolina causing rots
on fruit and other perishables. Ukeh and Chiejina (2012) reported that phytopesticides from two plants including Afromomium meleguata and Zingiber officinale
inhibited Penicillium digitatum, Mucor piriformis, Aspergillus niger and
Heminsthoporium solani causal agents involved with soft rot of tomato. Ijato et al.
(2011) reported the antimicrobial activity of Vernonia amygdalina and Tridax
procumbens each with two varying formulations and concentrations (aqueous
extracts: 80 and 60% and ethanol extracts: 30 and 20%) against A. niger, F.
oxysporum, G. candidum and Rhizopus stolonifer. Again, the aqueous and organic
solvents (water and ethanol) extracts from leaves of Chromolaena odorantum and
Azachirachta indica were reported to have antifungal activity against fungal
pathogens that cause tomato rots (A. niger, F. oxysporum, R. stolonifer and G.
candidium) by poisoned food method (Ijato et al. 2011).They showed that among
the various extracts with varying concentrations, ethanol extracts of 30% A. indica
had the best inhibitory effect (83.30%) against A. niger followed by 30% ethanol
extract of C. odorata (80.00%) against G. candidium which proved the potentiality
of the plant extracts for the control of postharvest and transit fungal rot of tomato
2 An Introduction to Bioactive Natural Products …
73