Научная статья на тему 'Changes in the viability of Strongyloides ransomi larvae (Nematoda, Rhabditida) under the influence of synthetic flavourings'

Changes in the viability of Strongyloides ransomi larvae (Nematoda, Rhabditida) under the influence of synthetic flavourings Текст научной статьи по специальности «Биологические науки»

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Ключевые слова
nematodes / antiparasitic activity / flavouring agents / benzaldehyde / citral / D-limonene / β-ionone

Аннотация научной статьи по биологическим наукам, автор научной работы — A. A. Boyko, V. V. Brygadyrenko

One of the most common nematodes of pigs globally is Strongyloides ransomi Schwartz and Alicata 1930. It usually causes aggravation of physiological indicators of its hosts and damage to their immune system. Also it is a good modelling object for the evaluation of the antiparasitic activity of new antihelminthic drugs. We conducted laboratory experiments to assess the effect of flavouring additives with flower odour (benzaldehyde, citral, D-limonene and β-ionone) upon the viability of S. ransomi larvae. The mortality rate was calculated for 24 hours exposure at four concentrations of each substance (10, 1, 0.1 и 0.01 g/l) with eight replications. The lowest LD50 values were obtained for citral (97 mg/l) and benzaldehyde (142 mg/l). These substances are recommended for further evaluation of their antihelminthic effect in experiments using laboratory animals. Unlike other substances, the effect of β-ionone and D-limonene even at a concentration of 10 g/l after 24 hours caused the death of <50% of S. ransomi larvae. The study of flavouring additives with flowery odour, which are permitted to be used in food for humans and also to be used in cosmetics, is a promising field for research aimed at the development of new antiparasitic drugs.

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Текст научной работы на тему «Changes in the viability of Strongyloides ransomi larvae (Nematoda, Rhabditida) under the influence of synthetic flavourings»

Regulatory Mechanisms

in biosystems

Regulatory Mechanisms

in

Biosystems

ISSN 2519-8521 (Print) ISSN 2520-2588 (Online) Regul. Mech. Biosyst., 8(l), 36-40 doi: 10.15421/021707

Changes in the viability of Strongyloides ransomi larvae (Nematoda, Rhabditida) under the influence of synthetic flavourings

A. A. Boyko*, V. V. Brygadyrenko**

*Dnipropetrovsk State Agrarian-Economic University, Dnipro, Ukraine **Oles Honchar DnipropetrovskNational University, Dnipro, Ukraine

Boyko, A. A., & Brygadyrenko, V. V. (2017). Changes in the viability of Strongyloides ransomi larvae (Nematoda, Rhabditida) under the influence of synthetic flavourings. Regulatory Mechanisms in Biosystems, 8(1), 36-40. doi: 10.15421/021707

One of the most common nematodes of pigs globally is Strongyloides ransomi Schwartz and Alicata 1930. It usually causes aggravation of physiological indicators of its hosts and damage to their immune system. Also it is a good modelling object for the evaluation of the antiparasitic activity of new antihelminthic drugs. We conducted laboratory experiments to assess the effect of flavouring additives with flower odour (benzaldehyde, citral, D-limonene and p-ionone) upon the viability of S. ransomi larvae. The mortality rate was calculated for 24 hours exposure at four concentrations of each substance (10, 1, 0.1 u 0.01 g/l) with eight replications. The lowest LD50 values were obtained for citral (97 mg/l) and benzaldehyde (142 mg/l). These substances are recommended for further evaluation of their antihelminthic effect in experiments using laboratory animals. Unlike other substances, the effect of p-ionone and D-limonene even at a concentration of 10 g/l after 24 hours caused the death of <50% of S. ransomi larvae. The study of flavouring additives with flowery odour, which are permitted to be used in food for humans and also to be used in cosmetics, is a promising field for research aimed at the development of new antiparasitic drugs.

Keywords: nematodes; antiparasitic activity; flavouring agents; benzaldehyde; citral; D-limonene; p-ionone

Article info

Received 11.12.2016 Received in revised form

14.01.2017 Accepted 19.01.2017

Dnipropetrovsk State Agrarian-Economic University, Voroshilov Str., 25, Dnipro, 49027, Ukraine Tel.: +38-097-296-42-10 E-mail:

boikoalexandra1982@gmail. com

Oles Honchar Dnipropetrovsk National University, Gagarin Ave., 72, Dnipro, 49010, Ukraine Tel.: +38-050-93-90-788 E-mail: [email protected]

Introduction

Helminthiasis causes significant economic damage to animal husbandry (Faye et al., 2003; Veneziano et al., 2004; Charlier et al., 2007; Cringoli, 2008; Yamov and Antropov, 2008; Ponomar et al., 2014a, b; Boyko et al., 2016). Pig farming is one of the most common sources of meat products. Among the parasites of pigs, the most common are nematodes, including strongyloidiasis agents (Knecht et al., 2011; Eysker et al., 2011; Samsonovich, 2012a; Maslova et al., 2015). Parasitisation by Strongyloides ransomi (Schwartz and Alicata, 1930) causes loss of concentration of albuminous and albumin fractions in the blood of piglets, loss of erythrocytes, hemoglobin, albumin, phagocytic and lysozyme activity and immune reaction (Samsonovich, 2012b).

Therefore determining the viability of helminths is significant for controlling their population, both in the host, and in the environment. Nowadays, synthetic antiparasitic drugs (Ponomar et al., 2013) are used and experiments of identifying the antihelminthic properties of plants are being conducted (Rahmann and Seip, 2006; Burke et al., 2009; Lu et al., 2010).

To fight pathogenic organisms, microbiologists and virusolo-gists are researching the effect of flavouring agents in food production (Chiang et al., 2005; Sato et al., 2006; Somolinos et al., 2008; Si et al., 2009; Belletti et al., 2010). Because pigs consume food not only of vegetable origin, but also of animal origin, their diet can include synthetic flavouring agents from the diet of humans. Therefore the objective of this research is to define the effect of flavouring agents upon the level of viability of S. ransomi larvae (Rhabditida, Strongyloididae).

Materials and methods

The faeces of pigs were studied to find S. ransomi larvae using the Baermann test (Zajac et al., 2011). The material was collected in the summer period in Dnipropetrovsk district, and then transferred to the laboratory in plastic containers at a temperature of 22-24 °C. S. ransomi culture is represented by larval stages of freely moving and parasitic forms (Van Wyk and Mayhew, 2013).

Larvae of first and second stage (freely moving) have a rhabdite-like oesophagus with two bulbuses. Their intestinal cells are not distinguishable. The parasitic form (third stage) is distinguished by a filariform oesophagus with no extensions; the intestine does not have cells which can be clearly distinguished through an optical microscope (Fig. 1).

After cultivation, the liquid with the larvae was put in test tubes (10 ml) by 4 ml and was centrifuged for four minutes at 1500 revolutions a minute. 1 ml of sediments with larvae was evenly weighed and put in 0.1 ml portions in plastic containers with a capacity of 1.5 ml. After that, 1 ml of the substance under research was added to the larval culture (20-40 ind.), which then was kept for 24 hours at a temperature of 22-24 °C. Four concentrations (10, 1, 0.1 u 0.01 g/l) of each of the flavouring agents were used in the experiments (Table 1), with eight replications.

Results

The flavouring agents citral, benzaldehyde exhibited the strongest effect on the viability of S. ramsomi larvae (Table 2).

Table 1

Properties and usage of flavouring agents* which were used for establishing the viability level of S. ransomi larvae

Name of the substance

Chemical formula

Structural formula

Properties

Content

in food industry

Usage

in medicine

Benzaldehyde C6H5CHO

D-limonene (1-me1hyl-4-isopropenylcyclohexene C10H16 -1)

colourless liquid with odour of bitter

cores of kernels of bitter almond, apricot kernels, stones

of peaches, cherries, black cherries and other stone fruits, as food additive no data concerning usage

almond or of apple

leaves of bird cherry tree, pulp

Citral (3,7- dimethyl -2,6-octadienal)

C10H16O

Bela-ionone ((3E)-4-(2,6,6-trimethylcyclohex C13H20O - 1-enyl)but-3-en-2-one)

pips

colourless liquid with odour of citrus

of oyster mushroom (Pleurotus ostreatus)

many essential oils, including citrus

as food additive no data concerning usage

viscous colourless or

essential oil of lemon grass

, . ,, ,, ~ ., (citronella), oil of cubeb, lemon bright-yellow fluid . , ., , ,

essential oil, eucalyptus and

with odour of lemon

some other essential oils

as food additive

antiseptics anti-inflammatory agent,

used to relieve intracranial hypertension

has a pleasant flower odour

some essential oils

as food additive no data concerning usage

Note: * - Official Journal of the European Union, L 354/46 (2008), Sun (2007), Smirnov (2008).

W'.

Fig. 1. S. ransomi larvae: a - noninvasional stage, b - filariform oesophagus, c - caudal end, d - outlet from the cuticle: length of black bar - 50 ^m

a

c

Table 2

LD50 (x ± SD) for S. ransomi larvae in laboratory experiment

Ha3BaHHe Be^ecraa LD50, Mr/ïï

Benzaldehyde 142 ± 64

D-limonene -

Citral 97 ± 36

Beta-ionone -

Note: «-» - the experiment did not achieve death of 50% larvae (needed concentration of more than 10 g/l).

D-limonene and beta-ionone at the studied concentrations (less than 10 g/m) did not affect the viability of S. ransomi larvae signifycantly, which shows that they are not useful as nematocidal medicines. The maximum effect upon the nematodes at LD90 (Fig. 2a, c) was shown by benzaldehyde at 685 mg/l. In this case, the larvae of the 100% nematodes studied perished in benzaldehyde solutions with a concentration of 1 and 10 g/l. Thus, this substance can be used for further development of veterinary drugs with anthelmintic effect.

Discussion

Nowadays research is being conducted on the extent of effect of flavouring agents on the viability of agents of infection. Chiang et al. (2005) discovered the antiviral function of a broad spectrum of apigenin, linalool and ursolic acid. These substances are extracted from basil, which is familiar in Chinese medicine as a medicinal plant. The antimicrobial function of these compounds such as linalool and citral is well attested. They are capable of inhibiting the growth of pathogenic microorganisms (Sato et al., 2006; Somolinos

et al., 2008; Si et al., 2009; Belletti et al., 2010). Research on the effect of citral on infectious agents also supports the findings from our experiments on the viability of S. ransomi larvae. The effect of benzaldehyde and beta-ionone has been insufficiently studied.

For pest control in agriculture a number of authors have suggested using the food flavouring agent cinnamic aldehyde and also acaricidal substances (Knoblauch and Fry, 2011; Na et al., 2011; Shen et al., 2012; Belkind et al., 2013). According to Shen et al. (2012), after using this flavouring agent for 24 hours, LD50 for Psoroptes was 107 mg/ml. Na et al. (2011) used it against Dermatophagoides of birds: LD50 after 24 hours was 0.54 mg/ml. This substance was also tested by Cheng et al. (2009) against mosquito larvae: during 24 hours LD50 was 40.8 mg/ml (LD90 = 81.7 mg/ml) and 46.5 mg/ml (LC90 = 83.3 mg/ml) for cinnamic aldehyde and cinnamic acetate, respectively. According to Lee et al. (2008), cinnamic aldehyde, benzaldehyde, linalool, limonene, alpha-Terpineol and other flavouring agents have insecticidal properties against Sitophilus oryzae (Linnaeus, 1763) (Coleoptera, Curculioni-dae): LD50 at 48 hours exposure was 0.004-0.200 mg/cm2.

As a fungicidal substance it is advised to use E210 (Codex Alimentarius), or benzoic asid, which is also included in other food additives, such as E211 - Sodium Benzoate, E212 - Potassium Ben-zoate, E2i3 - Calcium dibenzoate (Beerse et al., 2001; Amborabe et al., 2002; Joshi et al., 2008).

Methylparabene is used against fungi, and also as an antiseptic (Shapiro et al., 2002; Posey et al., 2005; Kromidas et al., 2006; Rebbeck et al., 2006; Ishiwatari et al., 2007; Gopalakrishnan et al., 2012). This substance is also included as a preservative in an insecticide aimed at controlling agricultural pests (Bell, 1990).

100 90 80 70 60 50 40 30 20 10 0

100 90 80 70 60 50 40 30 20 10 0

10000 1000

10000 1000

100

10

100 90 80 70 60 50 40 30 20 10 0

10000 1000

100

10

d

100

90 .......

80 □

70 JT

60

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50

40

30

20

10

0

$

10000 1000

100

10

Fig. 2. The effect of benzaldehyde (a), D-limonene (b), citral (c) and beta-ionone (d) on the viability of S. ransomi larvae: along the axes of abscissa - variant of experiment (mg/l), along the axes of ordinate - viability of S. ransomi larvae during 24 hours of laboratory experiment

(%); n = 8 for each variant of experiment

K

b

a

K

K

c

The flavouring agent benzaldehyde also shows insecticidal properties. The negative effect of benzaldehyde upon Galleria mello-nella (Linnaeus, 1758) has been demonstrated. Therefore it is recommended for use in developing new agricultural insecticidal preparations (Ullah et al., 2015). The effect of beta-ionone upon living organisms has received insufficient study. Indeed, the effect of entire groups of flavouring agents upon living organisms requires further studyin general.

Conclusions

We researched the effect of flavouring agents such as benzaldehyde, citral, D-limonene and beta-ionone upon the viability of S. ransomi, parasitic larvae on pigs. We determined the minimum values of LD50 for benzaldehyde and citral. Experimentally, a death rate of 50% of the tested larvae was not achieved using D-limonene and beta-ionone. Food additives with a pleasant flower odour, which are permitted to be used for food, and which are used as cosmetics, are important for evaluating potential new antihelminthic medical and veterinary preparations.

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