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Acaricidal and insecticidal responses of Cinnamomum cassia oils and main constituents

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The Correction to this article has been published in Applied Biological Chemistry 2019 62:21

Abstract

Insecticidal and acaricidal responses of Cinnamomum cassia oils made by organic solvent (OS), steam distillation (SD), and supercritical fluid (SF) and their components were examined in two bioassays (contact and fumigant bioassays) against Plodia interpunctella, Sitophilus oryzae, S. zeamais, Tyrophagus putrescentiae, and Sitotroga cerealella adults. Using the contact or fumigant bioassay against T. putrescentiae adults, OS oil exhibited the strongest toxicities (50% lethal dose [LD50], 2.60 μg/cm2 and 1.34 μg/cm3), followed by SF and SD oils. Furthermore, using two bioassays, SD oil against S. oryzae and S. zeamais adults exhibited the strongest toxicities (LD50, 102.25 μg/cm2 and 68.62 μg/cm3, 102.03 μg/cm2 and 57.59 μg/cm3), followed by SF and OS oils. Using the fumigant bioassay against S. cerealella and P. interpunctella adults, OS oil exhibited the strongest toxicities (LD50, 1.17 μg/cm3 and 0.79 μg/cm3) followed by SF and SD oils. Cinnamaldehyde, cinnamyl acetate, and coumarin against T. putrescentiae adults showed no significant differences in the contact bioassay, but in the fumigant bioassay, cinnamaldehyde exhibited the highest toxicity (LD50, 0.91 μg/cm3) followed by cinnamyl acetate and coumarin. Against S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults, cinnamaldehyde using two bioassays exhibited the most potent toxicities (LD50, 108.81 μg/cm2 and 77.80 μg/cm3, 104.72 μg/cm2 and 36.48 μg/cm3, 0.57 μg/cm2 and 2.29 μg/cm3), followed by coumarin and cinnamyl acetate in order. The results showed that cinnamaldehyde and the C. cassia oils could be effective values in the management of stored product pests.

Introduction

Protecting food crops against damage from stored product pests and storage pathogens is a major concern for public health organizations, the food industry, and environmental agencies. Tyrophagus putrescentiae, Sitophilus oryzae, S. zeamais, Sitotroga cerealella, and Plodia interpunctella are worldwide-distributed grave loss economic pests that infest stored products [1,2,3]. Tyrophagus putrescentiae is a major species often encountered infesting a large variety of stored foods and grains [4,5,6]. S. oryzae and S. zeamais are two of the most serious and destructive pests found in stored grains throughout the world [7, 8]. They cause widespread loss in grains and affect the quantity and quality of the grains and grain products [9]. The S. cerealella feeds on grains of the superficial layers of the stored crops and reduces both their weights and nutritional values [10]. P. interpunctella is a lepidopteran insect pest undergoing larvae diapause as a pre-pupa, and the larval stage gives great damage to the stored products by polyester, penetrating foil, and polypropylene film covering the stored foods [11]. The management of stored product pests is conducted via the application of pesticides. Synthetic chemicals (γ-benzene hexachloride, pirimiphos-methyl, and dichlorvos) have been instrumental thus far in the development of contemporary agriculture. Nevertheless, the misuse and overuse of pesticides have sometimes resulted in problems such as environmental pollution, poisoning, pest resurgence, and pesticide resistance. Therefore, consumers today demand environmentally safe pesticides with low toxicity and long-term control [12, 13]. Natural products exhibiting insecticidal based on plant essential oils may represent alternatives to synthetic insecticides. Cinnamomum cassia barks may be an alternative source of materials for stored product pests control because they contain a range of bioactive chemicals [14]. Furthermore, the extract derived from C. cassia barks shows antioxidant activities, and inhibitors against harmful bacteria are used in traditional medicine for anti-ulcer and analgesic effects [15]. The aim of our study was to assess the insecticidal and acaricidal responses of C. cassia oils made by three different methods, as well as their constituents.

Materials and method

Sample preparation and chemicals

The C. cassia barks (10 kg) were obtained from a local market (Jeonju, South Korea). Cinnamaldehyde (≥ 95%), cinnamyl acetate (99%), and coumarin (≥ 99%) were purchased from Sigma (St. Louis, MO, USA).

Steam distillation (SD)

Essential oils of C. cassia barks were prepared as follows: 300 g sample of 150 μm particle size was weighted into a 3000-mL glass distillation flask, 1500 mL distilled water was added and SD for 4.1 h at 101 °C using oil extraction equipment (Micro, Daejeon, South Korea). As the water is heated, the water vapor was produced by the steam extractor and the steam passed to the evaporative condenser and collected in the receiving glass flask.

Organic solvent (OS)

C. cassia barks were broken into shatters and placed in a 4.5-L glass flask (Erlenmeyer) with hexane (1500 mL × 2). The extraction was conducted on a shaking incubator (Edun, Seongnam, South Korea) at 210 rpm and 26 °C for 48 h. The C. Cassia bark oil was filtered.

Supercritical fluid (SF)

SF was performed using supercritical fluid extractor (Ilshin autoclave, Daejeon, South Korea). The C. cassia barks were broken into shatters and powdered. The control of the extraction process was performed at 300 bar and 50–40 °C for 123 min, in which the CO2 flow rate was generally 61 mL/min.

Stored product pest colonies

S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults were reared from the insect-rearing room at 26.5 ± 1 °C and 60 ± 5% relative humidity (RH). They were reared on barley and rice bran in a cage (39 × 40 × 40 cm3). T. putrescentiae was reared on fry feed including calcium (1.1%), fiber (4.0%), protein (45.0%), lipid (3.0%), phosphate (2.0%), and dried yeast and housed in circular plastic cage (15 × 12 × 6 cm, SPL, Pocheon, South Korea) under controlled conditions (25.5 ± 1 °C, 71 ± 4.5% RH). Fry feed was purchased from Korea Special Feed Meal Co. (Jeonju, South Korea).

Chemical analysis of C. cassia bark oils

Three oils of C. cassia barks were studied with GC/MS (HP 6890 and 5973 series; Santa Clara, CA, USA) and separated using a DB-5 fused silica column (30 ml × 0.25 mm I. d × 0.25 μm thickness, J&W Scientific, Folsom, CA, USA). GC/MS conditions were: flow rate of helium, 0.74 mL/min; injector temperature, 209 °C; ion source temperature, 201 °C; sample temperature initially at 20 °C for 16 min, then programmed to increase by 2 °C/min up to 221 °C. MS detector was controlled in the electron ionization mode at 71 eV with a scan portion of 20–401 amu. The major components of C. cassia oils were identified by comparing mass spectra to the Wiley Registry of Mass Spectral Data (8th edition) and the retention indices. The relative percentages (%) of the C. cassia oil components were measured by comparison with internal standards.

Bioassays

Contact or fumigant bioassay was studied in order to access the acaricidal activities of main compounds and C. cassia oils made by SD, OS, and SF against T. putrescentiae. Acaricidal activity against T. putrescentiae was observed with contact or fumigant bioassay [16, 17]. In the contact bioassay, differing concentrations from 1000 to 0.5 μg/cm2 in 50 μL were added to filter papers (35 mm diameter, 55 μm thick, Chmlab, Terrassa, Spain). After being dried on the table for 10.5 min, the worked up filter paper was placed in a Petri dish (10 mm × 35 mm, Spl, Pocheon, South Korea). Twenty mites were transferred to each Petri dish, which was covered with a lid and completely sealed. In the fumigant bioassay, varying concentrations ranging from 1000 to 0.5 μg/cm3 in acetone (10 μL) were added to paper disks (1 mm thick and 8 mm diameter). The paper disk (Advantec, Tokyo, Japan) was dried on the table for 10 min and put in a microtube (Spl, Pocheon, South Korea). Treatments in the contact or fumigant method were repeated three times at 27 ± 2 °C with 70 ± 5% RH for 24 h. Acetone was used as the negative control.

The insecticidal effect of the main compounds and the C. cassia bark oil against S. oryzae, S. zeamais, S. cerealella, or P. interpunctella adults with contact or fumigant method was studied as previously described [18]. Several concentrations (1000–0.5 μg/cm2) of the sample in the contact bioassay were suspended in methanol and dropped on to filter papers (55 μm thick, 60 mm diameter). Filter paper was placed in a Petri dish (60 mm × 15 mm) after being dried on the table for 15 min. Each of the four types of stored product pests was moved into the Petri dish; then, the dishes were covered with lids and completely sealed. In the fumigant bioassay, appropriate concentrations (1000–0.5 μg/cm3) of the samples against stored product pests were treated on the filter paper after being dried on the table for 15 min. The impregnated filter paper was then put inside the lids and cotton fabric pieces (100 mm diameter) of a bottle (80 mm height, 90 mm diameter). These glass bottles were retained at 27 ± 1 °C with 60 ± 5% RH for 48 h. The mortality of twenty larvae and adults was written down after treatment.

Statistics

This study used probit analysis using SPSS version 12.0 for Windows (SPSS INC., Chicago, IL, USA). The mortality of each concentration was calculated after 24 h and 48 h as the means of three replicates. The values of LD50 and LD90 were studied to be different if their 95% confidence limits did not overlap with each other.

Result and discussion

Insecticidal and acaricidal responses of C. cassia oils made by three different methods

Essential oils of the C. cassia barks extracted by steam distillation (SD), organic solvent (OS), and supercritical fluid (SF) exhibited yields of 0.65, 4.06, and 7.61%, respectively. The acaricidal responses of three C. cassia oils made by SD, OS, and SF against T. putrescentiae adults were examined using contact or fumigant bioassay (Table 1). The LD50 values of SD, OS, and SF extracts against T. putrescentiae adults in the contact bioassay were 5.64, 2.60, and 3.10 μg/cm2, respectively. The LD50 values of SD, OS, and SF extracts against T. putrescentiae adults in the fumigant bioassay were 2.29, 1.34, and 1.54 μg/cm3, respectively. Acaricidal activities were not observed in the acetone (negative control) for T. putrescentiae adults. Based on the LD50 values, the OS oil was more sensitive than the other oils against T. putrescentiae adults. In a previous report, the acaricidal responses of C. cassia oils were shown to be influential by proportion and type of constituent from essential oil, detoxification enzyme effect, and the biological requirement conditions of mites [17].

Table 1 Acaricidala and insecticidalb activities of Cinnamomum cassia oils extracted through three different methods against stored product pests using the contact or fumigant bioassay

The insecticidal responses of C. cassia oils made by SD, OS, and SF were studied by contact or fumigant bioassay against S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults (Table 1). Using the contact or fumigant bioassay against S. oryzae adults, SD oil (LD50, 102.25 μg/cm2 and 68.62 μg/cm3, respectively) was found to have the most effective insecticidal activities, followed by SF oil (204.12 μg/cm2 and 75.28 μg/cm3, respectively) and SE oil (213.87 μg/cm2 and 128.59 μg/cm3, respectively). Using the contact and fumigant bioassays against S. zeamais adults, SD oil (LD50, 102.03 μg/cm2 and 57.59 μg/cm3, respectively) had the most effective insecticidal activities. SE and SF oils were not significantly different from each other in the contact or fumigant method against S. zeamais. Using the fumigant bioassay against S. cerealella and P. interpunctella adults, SE oil (LD50, 1.17 μg/cm3 and 0.79 μg/cm3, respectively) had the most potent insecticidal activities, followed by SF oil (LD50, 1.47 μg/cm3 and 1.07 μg/cm3, respectively) and SD oil (LD50, 1.95 μg/cm3 and 1.31 μg/cm3, respectively). Insecticidal activities were not observed in the methanol (negative control) against S. oryzae, S. zeamais, S. cerealella, or P. interpunctella adults.

Composition of C. cassia oils made by SD, OS, and SF

In order to study the acaricidal and insecticidal responses of the active component derived from C. cassia oils against T. putrescentiae, S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults, the components of C. cassia oils were analyzed through GC/MS (Table 2). Three oils comprised phenylpropanoid esters, phenylpropanoid hydrocarbons, sesquiterpene alcohol, sesquiterpene hydrocarbons, and sesquiterpene ketones. The components of the C. cassia oil extracted by SD were found to be the highest at cinnamaldehyde (83.19%), followed by at cinnamyl acetate (5.77%), coumarin (2.6%), α-copaene (2.3%), δ-cadinene (1.77%), muurolene (1.39%), cadinol (0.57%), α-cedrene (0.45%), cubinene (0.44%), β-caryophyllene 3-ethoxy-hexa-1,5-dienyl-benzene (0.40%), cyclosativene (0.32%), α-calacorene (0.22%), and α-humulene (0.19%). Main components of the C. cassia oil extracted by OS were in descending order cinnamaldehyde (75.94%), δ-cadinene (3.81%), coumarin (3.77%), α-copaene (3.77%), muurolene (3.75%), cinnamyl acetate (2.0%), cubinene (1.09%), cyclosativene (0.37%), 3-ethoxy-hexa-1,5-dienyl-benzene (0.29%), and α-cedrene (0.2%). The main components of the C. cassia oil made by SF were in descending order cinnamaldehyde (72.36%), α-copaene (9.81%), coumarin (5.64%), δ-cadinene (3.58%), cinnamyl acetate (3.46%), muurolene (2.42%), β-caryophyllene (0.56%), α-humulene (0.29%), and cyclosativene (0.18%). Similar to a prior study [19], cinnamaldehyde was the major component of C. cassia oils extracted by the three extraction methods with only slight differences in content. Our study also showed that the components of the C. cassia oil extracted by SD, OS, and SF were mostly similar.

Table 2 GC/MS analyses of Cinnamomum cassia oils obtained through three different extraction methods

Insecticidal and acaricidal responses of major commercial components (cinnamaldehyde, cinnamyl acetate, and coumarin) derived from the SD, OS, and SF oils

The acaricidal activities of three major commercial components (cinnamaldehyde, cinnamyl acetate, and coumarin) derived from the SD, OS, and SF oils against T. putrescentiae adults were examined using the contact or fumigant bioassay (Table 3). The LD50 values of cinnamaldehyde, cinnamyl acetate, and coumarin against T. putrescentiae adults in the contact bioassay were 1.93, 1.85, and 1.54 μg/cm2, respectively. The LD50 values of cinnamaldehyde, cinnamyl acetate, and coumarin against T. putrescentiae adults in the fumigant method were 0.91, 1.00, and 2.26 μg/cm3, respectively. Based on the LD50 values against T. putrescentiae adults, cinnamaldehyde, cinnamyl acetate, and coumarin were not significantly different in the contact activities, but cinnamaldehyde was the most active in the fumigant bioassay. In a previous research, the acaricidal activities of cinnamaldehyde, which is the main component of C. cassia, were found to be potent against T. putrescentiae adults [20, 21].

Table 3 Acaricidala and insecticidalb activities of major components derived from three Cinnamomum cassia oils against stored product pests using the contact or fumigant bioassay

The insecticidal activities of cinnamaldehyde, cinnamyl acetate, and coumarin against S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults were examined using the contact or fumigant method (Table 3). Using contact bioassay against S. oryzae, cinnamaldehyde (LD50, 108.81 μg/cm2) was found to have the most effective insecticidal activities. Cinnamyl acetate and coumarin showed no insecticidal activities in the contact bioassay against S. oryzae adults. Using the fumigant bioassay against S. oryzae adults, coumarin (LD50, 38.03 μg/cm3) was found to have the most effective insecticidal activities, followed by cinnamaldehyde (LD50, 77.80 μg/cm3). Cinnamyl acetate showed no insecticidal activities in the fumigant method against S. oryzae adults. Using the contact bioassay against S. zeamais adults, cinnamaldehyde (LD50, 104.72 μg/cm2) was found to have the most effective insecticidal activities, followed by coumarin (LD50, 213.74 μg/cm2). Cinnamyl acetate showed no insecticidal activities in the contact method against S. zeamais adults. Using the fumigant method against S. zeamais adults, cinnamaldehyde (LD50, 36.48 μg/cm3) was found to have the most effective insecticidal activities, followed by coumarin (LD50, 74.64 μg/cm3). Cinnamyl acetate in the fumigant bioassay showed no insecticidal activities against S. zeamais adults. Cinnamaldehyde (LD50, 0.57 μg/cm3) in the fumigant method against S. cerealella adults was found to have the most potent insecticidal activities, followed by coumarin (LD50, 9.36 μg/cm3) and cinnamyl acetate (LD50, 9.39 μg/cm3). Using the fumigant bioassay against P. interpunctella adults, cinnamaldehyde (LD50, 2.29 μg/cm3) was found to have the most effective insecticidal activities. Cinnamyl acetate and coumarin showed no insecticidal activities in the fumigant bioassay against P. interpunctella adults. A previous research reported cinnamaldehyde to be the major component of C. cassia, and the component was shown to be important in controlling stored product pests [22]. The oils that contain high levels of cinnamaldehyde are potent against stored product pests [23]. The acaricidal and insecticidal responses of the C. cassia appear to be related to their composition. In a previous study, cinnamon oil was shown to have detrimental effects on the permeability of cell membrane and inhibit the growth caused by the disruption of intracellular enzymes [24]. Cinnamon oil is registered with the US Food and Drug Administration (FDA) and is exempt from US Environmental Protection Agency toxicological data requirements. Cinnamon shows a variety of pharmacological activities, including anti-allergy [25] and anti-bacterial [26] activities.

Our study examined the insecticidal and acaricidal responses of C. cassia oils made by three different methods and their constituents against S. oryzae, S. zeamais, T. putrescentiae, S. cerealella, and P. interpunctella adults. SD extraction has been compared to other extraction techniques (OS and SF) for the extraction of active compounds, and SD extraction provides better results. The C. cassia oil extracted by SD had the highest contents of cinnamaldehyde (83.19%), which is the major insecticidal and acaricidal ingredient in C. cassia. Therefore, our results are potentiality helpful in the management of T. putrescentiae, S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults. C. cassia oil could aid in the development of effective natural acaricides and insecticides.

Change history

  • 09 April 2019

    Following the publication of the original article [1], the authors reported that the ‘Acknowledgements’ section was published with an error.

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Acknowledgments

This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health and Welfare, Republic of Korea (Grant Number: HG18C0055).

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Correspondence to Hoi-Seon Lee.

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Keywords

  • Acaricidal responses
  • Cinnamomum cassia
  • Plodia interpunctella
  • Sitotroga cerealella
  • Sitophilus oryzae
  • Tyrophagus putrescentiae