Ar-turmerone from Curcuma longa (Zingiberaceae) rhizomes and effects on Sitophilus zeamais (Coleoptera: Curculionidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae)
Graphical abstract
Highlights
► Ar-turmerone is highly toxic to S. zeamais and S. frugiperda at low doses. ► Ar-turmerone has significant repellent action against S. zeamais. ► Ar-turmerone can persist for 45 days at a dose of 10 μL per 20 g corn grain. ► Ar-turmerone could be a lower cost and sustainable alternative for IPM.
Introduction
Persistent, broad-spectrum insecticides can be toxic to non-target organisms and also cause environmental damage (Vianna et al., 2009, Tavares et al., 2010a, Castro et al., 2012). Furthermore, they can result in the evolution of resistant individuals, necessitating research into new substances with insecticidal activity and new methods of controlling insect pests; for example, several studies have examined the antifeedant and repellent activity of molecules from plants of the Cerrado (Savanna-type) biome of Brazil (Pereira et al., 2002, Tavares et al., 2009, Tavares et al., 2011).
Turmeric, Curcuma longa L. (Zingiberaceae) is an herbaceous perennial and with long lateral ramifications that originated in Southeast Asia, probably from India (Sharma et al., 2011). Turmeric powder is extracted from the dried ground rhizomes and has many culinary uses (Hammerschmidt, 1997, Palaniswamy, 2001, Tilak et al., 2004). Compounds formed by the plant also have antioxidant, antibacterial, anti-inflammatory, analgesic and digestive properties, and some are currently being investigated as treatments for cancer, Alzheimer's disease and liver problems (Chattopadhyay et al., 2004, Ali et al., 2006, Mariyappan and Vijayaragavan, 2007). The fresh juice, water extracts and essential oils of C. longa also show insecticidal activity against insect pests and act as mosquito repellents (Iqbal et al., 2010a, Sukari et al., 2010, Damalas, 2011). C. longa is harvested when the aerial part is lost after flowering and its rhizomes are an intense yellow, possibly indicating the presence of more concentrated pigments (Bambirra et al., 2002, Hossain, 2010).
Genetic factors, harvesting time, individual plants, soil type, fertilization, time of collection, mode of drying the plant material, storage period and environmental factors all affect the chemical composition and the content of essential oils from C. longa rhizomes (Bansal et al., 2002, Chane-Ming et al., 2002, Naz et al., 2011). The composition and volatility of C. longa essential oils determine the characteristic smell of turmeric, whereas fixed phenolic compounds, such as curcumin and its derivatives, are responsible for the intense yellow color of the rhizomes. Volatile essential oils of C. longa contain a mixture of ketones and sesquiterpene alcohols, the latter being mainly of a form of germacrene and bisabolane (Zhang et al., 2008, Li et al., 2010, Xiao et al., 2011).
The Maize weevil Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) is a serious pest of grain crops, both in the field and in storage units, where it can lead to cross-infestation (Tigar et al., 1994, Demissie et al., 2008, Vazquez-Castro et al., 2009). Larvae and adults of this pest damage whole and healthy grains, including oat Avena sativa L., barley Hordeum vulgare L., rice Oryza sativa L., rye Secale cereale L., wheat Triticum aestivum L. and corn Zea mays L. (Poaceae) (Lale and Yusuf, 2000, Ukeh et al., 2010). The weevil lays its eggs within the grain, where the larvae then develop (Larrain et al., 1995). Detrimental effects result from the reduced weight and poorer physical and physiological quality of the infected grains, which result mainly from the additional effect of deterioration agents (microorganisms) (Hell et al., 2000). Because the larvae develop inside the grain, it is difficult to use insecticides against this pest; therefore, they are a promising system to use to study the effect of alternative repellent substances (Huang et al., 2011).
The fall armyworm Spodoptera frugiperda J.E. Smith, 1797 (Lepidoptera: Noctuidae) is a major corn pest in Brazil (Cruz et al., 1999, Senna et al., 2003, Tavares et al., 2010b). Caterpillars of S. frugiperda first feed on the remains of their eggshells, where they stay undisturbed for 10–12 h, at which point they begin to feed on the green and succulent tissues of the plant, leaving the membranous epidermis intact (Barros et al., 2010). Fresh droppings indicate the presence of caterpillars inside the maize cartridge (Busato et al., 2004). Maize is more sensitive to S. frugiperda 40–45 days following germination. Pesticides and insecticides can only be applied when approximately 20% of the plants are affected and the caterpillars are 10–12 mm long to reduce any adverse effects on natural enemies of this species (Figueiredo et al., 1999). Contact insecticides are effective against the eggs and young S. frugiperda caterpillars on the outside of the plant, whereas compounds with antifeedant properties are more effective against caterpillars within the plant (Adamczyk et al., 1999, Al-Sarar et al., 2006, Blessing et al., 2010).
The objective of the current study was to identify the compound ar-turmerone, extracted and purified from C. longa rhizomes and to determine its insecticidal and repellent effects on S. zeamais and S. frugiperda.
Section snippets
Experimental procedures
1H, 13C, HSQC and HMBC NMR measurements were carried out on a Bruker Avance III 500 instrument (operating at 500.13 MHz for 1H) equipped with a 5 mm triple Resonance broadband inverse probehead (TBI) with Z-gradient. CDCl3 was used as solvent and tetramethylsilane (TMS) as the internal standard. Mass spectra were obtained by gas chromatography coupled to a mass spectrometry (GC–MS). The GC–MS analyzes were performed using a gas chromatograph [GC-17A Shimadzu, GC–MS/QP5,000 Shimadzu, DB-5 column
Results and discussion
The extraction yield of C. longa essential oil with hexane was 0.39% (m m−1) (1.93 g) and the yield of ar-turmerone obtained from this essential oil was 82% (m m−1) after the chromatographic separations from starting material (1.58 g). These values indicate that 3.2 g of ar-turmerone is present per 1000 g rhizomes of this plant grown in Catalão, Goiás State, Brazil. High percentages of ar-turmerone in nonpolar extracts and essential oils of C. longa have also been reported from China, India, Nigeria,
Conclusions
The ar-turmerone is highly toxic to S. zeamais and S. frugiperda at low doses. This sesquiterpene has significant repellent action against S. zeamais and can persist in the environment for 45 days at a dose of 10 μL per 20 g corn grain. Therefore, ar-turmerone could be a lower cost and sustainable alternative in Brazil for integrated pest management of these species.
Dedication
To Professor Fernando Petacci (Chemistry Department, Federal University of Goiás in Catalão, Goiás State, Brazil) that died on June 15, 2012 and Professor Sérgio de Freitas (Faculty of Agriculture and Veterinary Sciences, Paulista Estadual University “Júlio de Mesquita Filho” in Jaboticabal, São Paulo State, Brazil) that died on February 21, 2012. Our sincere feelings.
Acknowledgements
To Dr. Ivan Cruz (EMBRAPA Maize and Sorghum in Sete Lagoas, Minas Gerais State, Brazil) for providing logistical support. To Dr. Aristônio Magalhães Teles (Institute of Biological Sciences – General Biology Department – Federal University of Goiás in Goiânia, Goiás State, Brazil) to identify C. longa (Zingiberaceae). To M.Sc. Amauri Alves de Souza Júnior (Institute of Chemistry – Paulista Estadual University “Júlio de Mesquita Filho” in Araraquara, São Paulo State, Brasil) for help in
References (65)
Curcuma longa: culinary turmeric
J. Lab. Clin. Med.
(1997)- et al.
Bioactivities of essential oil from Elletaria cardamomum (L.) Maton. to Sitophilus zeamais Motschulsky and Tribolium castaneum (Herbst)
J. Stored Prod. Res.
(2000) - et al.
Methods of infestation of sorghum lines for the evaluation of resistance to the maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)
Crop Prot.
(1995) - et al.
Insecticidal activities of ar-turmerone identified in Curcuma longa rhizome against Nilaparvata lugens (Homoptera: Delphacidae) and Plutella xylostella (Lepidoptera: Yponomeutidae)
J. Asia Pac. Entomol.
(2001) - et al.
Quantitative determination of eight components in rhizome (Jianghuang) and tuberous root (Yujin) of Curcuma longa using pressurized liquid extraction and gas chromatography-mass spectrometry
J. Pharmaceut. Biomed.
(2007) - et al.
Potential use of Asteraceae extracts to control Spodoptera frugiperda (Lepidoptera: Noctuidae) and selectivity to their parasitoids Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) and Telenomus remus (Hymenoptera: Scelionidae)
Ind. Crop. Prod.
(2009) - et al.
Field and post-maturation infestation of maize by stored-product pests in Mexico
J. Stored Prod. Res.
(1994) - et al.
Bisabocurcumin, a new skeleton curcuminoid from the rhizomes of Curcuma longa L
Chin. Chem. Lett.
(2011) The consumption and utilization of food by insects
Adv. Insect Physiol.
(1968)- et al.
Qualitative and quantitative analysis of four species of Curcuma rhizomes using twice development thin layer chromatography
J. Pharmaceut. Biomed.
(2008)