WO2022250524A1

WO2022250524A1 - Plant-based bioinsecticide composition

Info

Publication number: WO2022250524A1
Application number: PCT/MY2022/050039
Authority: WO
Inventors: Norhayu ASIB; Dzolkhifli OMAR; Masdah NAWI; Anis Syahirah MOKHTAR
Original assignee: Universiti Putra Malaysia
Priority date: 2021-05-28
Filing date: 2022-05-25
Publication date: 2022-12-01

Abstract

The present invention relates to plant-based bioinsecticide composition comprising: saponin; azadiractin; surfactant; and carrier. The saponin is extracted from Piper samertosum; and the azadiractin is extracted from Azadiracta indica. The plant-based bioinsecticide composition of the present invention shows synergistic effect against brown planthopper. The present invention is safe to mammals, biodegradable, renewable and does not cause environmental pollution and not as harmful and environmental polluted as the chemical insecticide.

Description

PLANT-BASED BIOINSECTICIDE COMPOSITION

Field of Invention

The present invention relates to bioinsecticide composition. More particularly, the present invention relates to a plant-based bioinsecticide composition.

Background of the invention

Nilaparvata lugens, brown planthopper (BPH) is an important rice pest that destroying rice by feeding on the plant sap and causing a condition known as ‘hopperburn’, where the plants are completely wilting, yellowing and drying. BPH is a plant hopper species from order Hemiptera and family Delphacidae with brown coloured wings of adult and creamy white nymph. BPH caused serious damage on rice crop by directly feeding on the plant phloem which lead to browning, drying and wilting of the plant (Tang et. al., 2010). The most used control method of BPH is by using chemical control but recently, BPH was found to build resistance against chemical pesticide. The high level of resistance to imidacloprid resulted in chemical control failure and great yield loss in 2005 (Wang et. al., 2008). The constant and unsystematic use of one insecticide has resulted in the quick development of insecticide resistance and exhaustion of most insecticide alternative in many rice-growing country (Chen et. al., 2013).

P. sarmentosum , also called wild betel or in Malay name known as ‘kaduk’, is plant from order Piperales and family Piperaceae (Maizatul and Nor Farahiyah, 2018). It is a perennial herb that have a creeping rhizome and striped stem that grow up to 40cm. The heart- shaped and alternate leaves are light to dark green in colour with a waxy surface (Sharifah Farhanah et. al., 2016). It can be found in tropical areas of Southeast Asia, Northeast India and South China. A. indica also known as neem is an evergreen plant from order Sapindales and family Meliaceae, the most common medicinal plants that has got worldwide attention because of its medicinal and insecticide properties (Sonal and Pankaj, 2014).

Since P. sarmentosum and A. indica are abundance and can be easily found and grown in Southeast Asia, there are a lot of interest among the researchers in exploring the usage and application of these herbs plants in various field including in agricultural sector for pest control. There are several prior arts that have explored and applied the extract derived from the P. sarmentosum and A. indica for pest control. According to Abdelrahim et. al., (2013), neem extracts of various parts were studied and verified to be effective in controlling broad spectrum of insects among Coleoptera, Diptera, Hemiptera, Homoptera and Lepidoptera. According to Qin et. al., (2010), there were experimental evidence of the application of P. sarmentosum in botanical pesticides. Piper leaves exhibits strong repellent and antifeedant effects against larvae and imagoes of the diamondback moth. However, none of them has encounter the application of both P. sarmentosum and A. indica and produce significant synergistic effects against insects especially in agricultural sector. Therefore, it is important to explore other common practices to control the pest from damaging the valuable plants especially in a large area like paddy field or orchard farms in order to control the usage of chemicals substance which may harm people and environments in a long run.

Summary of the Invention

An aspect of the present invention is to provide plant-based bioinsecticide composition comprising: saponin; azadiractin; surfactant; and carrier; characterized in that the saponin is extracted from Piper samertosum and the azadiractin is extracted from Azadiracta indica. Accordingly, the composition is in the form of nanoemulsion.

Accordingly, the nanoemulsion is preferably having particle sizes below 250nm. Accordingly, the Piper samertosum and Azadiracta indica is preferably in ratios of 6:4, 7:3 and 9:1.

Accordingly, the surfactant is plant based selected from Ethoxylated castor oil, Ricinus communis

Accordingly, the carrier is vegetable based selected from palmitic acid derived from palm oil

Accordingly, the amount of the saponin and azadiractin is selected within the range of 1% to 10%.

Accordingly, the amount of the surfactant is selected within the range of 5% to 15%. Accordingly, the amount of the carrier is selected within the range of 50% to 90%. Accordingly, the plant-based bioinsecticide composition is used against brown planthopper, Nilaparvata lugens.

Advantegously, the plant-based bioinsecticide composition of the present invention shows synergistic effect against brown planthopper.

Advantegously, the plant-based bioinsecticide composition of the present invention is biodegradable, renewable and does not cause environmental pollution.

Brief Description of the Drawings of the Present Invention

The present invention shall now be further explained in the following examples with reference to the accompanying figures, nevertheless, without being limited thereto. For the purposes of the present invention, all references as cited herein are incorporated by reference in their entirety’s inn the Figures,

Figure 1 illustrates ternary phase diagrams of Termul 1285, Edenor, Water;

Figure 2 illustrates ternary phase diagrams of Tween 80, Edenor, Water;

Figure 3 shows particle size of formulations.

Details Description of the Invention

The present invention relates to plant-based bioinsecticide which combine active ingredient saponin and azadirachtin extracted from Piper samertosum and Azadiracta indica respectively. Combination of the both active ingredients provide synergistic effect against insects especially brown planthopper. Synergistic effect can be defined as the effects when chemical substances or biological structures interact resulting in an overall effect that is greater than the sum of individual effects of any of them. The combination of both active ingredients of the present invention produces synergistic effect based on the LC50 values < 0.014 pg/mL against brown planthopper. In details, combination ration of both active ingredients are preferably in ratios of 6:4, 7:3 or 9:1.

The plant-based bioinsecticide composition of the present invention further comprising carrier and surfactant which also derived from plant based. In details, the carrier is vegetable based selected from palmitic acid derived from palm oil.

The surfactant is plant based selected from Ethoxylated castor oil, Ricinus communis.

In one embodiment, the plant-based bioinsecticide composition of the present invention is preferably in the form of nanoemulsion having particle sizes below 250nm with zeta potential above than 40mV.

In another embodiment, there are range of amount for each of the substance in the plant- based bioinsecticide composition of the present invention in order for the composition to achieve high performance. Accordingly, the amount of the saponin and azadiractin is selected within the range of 1% to 10%. The amount of the surfactant is selected within the range of 5% to 15%. The amount of the carrier is selected within the range of 50% to 90%.

In yet another embodiment, the application of the plant-based bioinsecticide composition of the present invention shows synergistic effect against brown plathopper and a potent preparation but safe to mammals as it is harmless to the human or animal skin.

The plant-based bioinsecticide composition of the present invention is also biodegradable, renewable and does not cause environmental pollution. Embodiments of present invention will be clearly described in the following examples below in order for the present invention to be more readily understood. It is to be understood that the following example is for illustrative purpose only and should not be construed to limit the present invention in any way.

EXAMPLE 1

Synergism activity of A.indica and P. sarmentosum.es. tract against N.lugens a. Insect collection

BPH was collected from several area of paddy fields in Selangor randomly and was brought to the laboratory and reared at room temperature 28°C±2 with 70 to 80% humidity for 12 hours daylight and 12 hours dark. Rice seed from susceptible rice varieties without resistant genes was used in this study. Untreated rice plant of about 3 to 4 weeks was used as host plant where the BPH used the plant sap as food source and for the adult females to lay eggs. Rice plant also had been used for treatment and bioassay. b. Extraction of A.indica and P. sarmentosum

The seed of Adndicaand leaves of P. sarmentosum was dried up for 3 days in oven at 50°C to ensure no moisture left before being ground into fine powder using electronic grinder. The extract powder was soaked with solvent hexane. 150 g of extract powder was soaked in 1 litre hexane for 3 days and was shaked in every 24 hours. The extract was filtered using vacuum pump through filter paper. The crude extract was obtained after extraction using rotary evaporator. c. Insecticidal activity of combination extract of A.indica and P. sarmentosum

Crude extracts of A.indica and P. sarmentosum was tested individually and also in a mixture of mass ratio (1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, 9:1) for their insecticidal activity against BPH. From the toxicity test, it was found that mixture of mass ratio of 6:4, 7:3 and 9:1 (P. sarmentosum : A.indica ) gave the highest mortality rate and highest index combination value, which showed that these mixture ratio have synergistic action against BPH. Table 1: Mortality rate and combination index value of extracts mixture against BPH

EXAMPLE 2

Preparation of combination formulation of A.indica and P. sarmentosum a. Construction of ternary phase diagrams (TPD)

A formulation composition had been selected from two TPD which successfully developed a clear 1-phase. Both formulations were obtained at ratio of 15:80:5 where the first formulation is mixture of Tween 80 surfactant, Edenor oil and water (Figure 1), while second formulation mixture of Termul 1284 surfactant, Edenor oil and water (Figure 2). b. Emulsion formulation extract

Formulation composition from TPD which regarded as inert ingredient (95%) had been added into active ingredient (5%), which is the mixture of of A.indica and P. sarmentosum extracts. Six formulation had been produced as below:

Table 2: Formulation composition

a. Stability test

All formulation was kept for stability test at 3 different temperature, at -20°C and 54°C for 14 days and at 25°C for 60 days. All formulation at all temperature were found to be physically stable (1-phase) after the recorded period. b. Zeta potential and particle size distribution

According to Joseph and Singhvi (2019), zeta potential value other than -30 mV to +30 mV is generally considered to have sufficient repulsive force to attain better physical colloidal stability. This is supported by Riddick (1968), which stated that formulation with zeta potential value of -41 to -60 mV is considered to have a fairly good stability, while value of -61 to -80 mV is considered to have very good stability. As shown in Table 3, the minimum value of zeta potential is -67.7mV and the maximum is -44mV.

Polydispersity index (PDI) is a parameter used to define the size range of particle of given sample. Values <0.05 indicates highly monodisperse standards. Values of <0.2 are most acceptable in practice for polymer-based nanoparticle materials. Value of <0.3 indicates a homogenous population of phospholipid vesicles. Values >0.7 show that a sample has a very broad particle size distribution and is probably not suitable to be analyzed by the dynamic light scattering (DLS) technique (Danaei et al, 2018). PDI shows the uniformity of droplet size in nanoemulsion. The lower the value of polydispersity, the higher the uniformity of droplet size of nanoemulsion (Jaiswal et al. 2015).

The particle size or its distribution of the disperse phase affect the stability, viscosity, rate of heat transfer, and optical properties of emulsions (Groves and Freshwater 1986). As shown in Figure 3, the lowest particle size is FI at 202.5 dnm and the highest is F6 at 635.9 dnm. Nanoemulsion is the transparent state where interfacial film of surfactant molecule with droplet size range 20-600 nm stabilizing the oil in water or water in oil dispersion (Jaiswal et al. 2015). According to Hu et al. (2021), as the particle size decreases, the attractive interactions between the droplets tend to decrease more rapidly than steric repulsion, and this improves the stability of nanoemulsions.

Table 3: Zeta potential, particle size and PDI data

Table 3: Zeta potential, particle size and PDI data (continue)

Viscosity test

Table 4 shows the viscosity reading taken from Viscometer NDJ-5S at 4 different rotation speed, 6, 12, 30 and 60 rpm, where the viscosity is measured using unit millipascal per second (mPa.s).

Table 4: Viscosity data

As shown in Table 4, viscosity reading decrease as the speed increase. Following the study by Martinez et al. 2004, the viscosity of the emulsion increases about 150 cP when the speed is increased from 1000 to 1500 rpm and increases only about 110 cP when the speed is increased from 1500 to 2500 rpm. According to Marco et al. (2005), the volume fraction of dispersed phase and temperature have the major influence on the viscosity effectiveness of water-in-oil emulsions along with several minor influence of shear rate, average droplet size, droplet size distribution, viscosity and density of oil. Study by Goodarzi and Zendehboudi (2019) concluded that viscosity reduction is caused by increasing in droplet size. Viscosity decreases by increasing temperature but when the temperature goes up as high as 90 °C, the viscosity will increase as a result of the increasing temperature due to the phase inversion. (Anisa and Nour, 2010).

Table 5: Summary of Particle size, Zeta potential, Viscosity, stability and Poly dispersibility index data.

The particle size of selected formulations in Table 5 ranged from 202.5 to 506.9 dnm. Bouchemal et al. (2004) stated that the ideal particle size range of nanoemulsion is within 100- 600 nm. The zeta potential of three formulations in Table 5 ranged from -48.3 to -59.2. There are many views to consider which value ranges of zeta potential that indicated the most stability of the nanoemulsion. According to Joseph, et al (2019), stated that a greater number of positive and negative values of zeta potential signify good physical stability of particles. The readings of PDI value of FI, F2 and F3 were 0.359, 0.332 and 0.485, respectively. According to Malvern, the best PDI value is within the range 0.08 to 0.7 and PDI value more than 0.7 indicates a broadness of particle size.

In conclusion, stable formulation can be developed following the current results and findings. These will lead to prove the synergism efficacy of A.indica and P. sarmentosum against BPH through emulsion formulations as joint toxicity could have a better potency in controlling pests, compared to individual active ingredient.

As will be readily evident to those skilled in the art, this invention may easily be produced in other definite forms without leaving from its scope or essential characteristics. These examples are, therefore, to be considered as only illustrative and not restrictive, the scope of the invention being indicated by the claims rather than the former description.

Claims

1. Plant-based bioinsecticide composition comprising: saponin; azadiractin; surfactant; and carrier; characterized in that the saponin is extracted from Piper samertosum and the azadiractin is extracted from Azadiracta indica.

2. The plant-based bioinsecticide composition according to Claim 1, wherein the composition is in the form of nanoemulsion.

3. The plant-based bioinsecticide composition according to Claim 2, wherein the nanoemulsion is preferably having particle sizes below 250nm.

4. The plant-based bioinsecticide composition according to Claim 1, wherein the Piper samertosum and Azadiracta indica is preferably in ratios of 6:4, 7:3 or 9:1.

5. The plant-based bioinsecticide composition according to Claim 1 , wherein the surfactant is plant based selected from Ethoxylated castor oil, Ricinus communis.

6. The plant-based bioinsecticide composition according to Claim 1, wherein the carrier is vegetable based selected from palmitic acid derived from palm oil.

7. The plant-based bioinsecticide composition according to Claim 1, wherein the amount of the saponin and azadiractin is selected within the range of 1% to 10%.

8. The plant-based bioinsecticide composition according to Claim 1, wherein the amount of the surfactant is selected within the range of 5% to 15%.

9. The plant-based bioinsecticide composition according to Claim 1, wherein the amount of the carrier is selected within the range of 50% to 90%.

10. Use of the plant-based bioinsecticide composition according to Claim 1 against brown planthopper, Nilaparvata lugens.