|Year : 2021 | Volume
| Issue : 3 | Page : 258-266
The content of active materials in miswak (Salvadora persica): An Analytical study using Fourier-transform infrared spectroscopy and ultraviolet–visible spectrophotometer
Ayu Tri Jayanti1, Aulia Nasution2, Hery Suyanto3, Taufan Bramantoro4, Al Rizqi Fauziyah1
1 Department of Engineering Physics, Faculty of Industrial Technology and System Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, East Java, Indonesia
2 Department of Engineering Physics, Faculty of Industrial Technology and System Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, East Java, Indonesia; Dental Public Health and Primary Health Care Research Group, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, East Java, Indonesia
3 Physics Department, Faculty of Mathematics and Natural Sciences, Udayana University, Jimbaran-Bali, Indonesia
4 Faculty of Dental Medicine, Universitas Airlangga, Surabaya, East Java, Indonesia
|Date of Submission||11-Sep-2020|
|Date of Decision||05-Oct-2020|
|Date of Acceptance||17-Dec-2020|
|Date of Web Publication||18-Jun-2021|
Dr. Aulia Nasution
Department of Engineering Physics, Faculty of Industrial Technology and System Engineering, Institut Teknologi Sepuluh Nopember, and Dental Public Health and Primary Health Care Research Group, Faculty of Dental Medicine, Universitas Airlangga Surabaya, East Java.
Source of Support: None, Conflict of Interest: None
Aim: The trend of cleaning teeth with miswak amidst the modern technological developments can be found in the majority of large countries. Many advantages of miswak increase its trade throughout the world, causing it to be easily obtainable on the market. However, until now, there have not been many studies that explain the active substances in miswak sold on the market. This study aims to analyze the content of active substances from various types of miswaks, which are sold freely on the market. Materials and Methods: A total of five miswaks from Saudi Arabia and Pakistan were taken as the study sample. The miswak was divided into three types of samples: powder, extract, and evaporated extract samples. All miswaks were extracted using maceration method. The chemical content was tested using Fourier-transform infrared (FTIR) spectroscopy and an ultraviolet–visible (UV–Vis) spectrophotometer. The research results were analyzed using Origin software. Results: FTIR test of the miswak powder showed that miswak B had a dominant phosphoric acid (PH) group and pH ester with a wave range of 2425-2325 cm‒1. The FTIR test of the miswak extract showed phosphorus atoms at wavenumber 867.96 cm‒1 with PO groups and 430.01 cm‒1 with the P-Cl group in the compound. UV–Vis test of the miswak extract showed that miswak B and miswak E had higher absorbance values than other miswaks. The UV–Vis test of the evaporated miswak extract resulted in the breakdown of molecular bonds in miswak E after going through the evaporation process, causing more than one wave peak to be produced. The FTIR test of the evaporated miswak extract showed that miswak R had a strong bond between molecules. Hence, the PH group is not broken during the evaporation process. Conclusion: Miswaks which are sold freely in the market contain an active substance in the form of phosphoric acid which consists of phosphorus atoms which are beneficial to human teeth and bones.
Keywords: FTIR spectroscopy, miswak, oral health, Salvadora persica
|How to cite this article:|
Tri Jayanti A, Nasution A, Suyanto H, Bramantoro T, Fauziyah AR. The content of active materials in miswak (Salvadora persica): An Analytical study using Fourier-transform infrared spectroscopy and ultraviolet–visible spectrophotometer. J Int Oral Health 2021;13:258-66
|How to cite this URL:|
Tri Jayanti A, Nasution A, Suyanto H, Bramantoro T, Fauziyah AR. The content of active materials in miswak (Salvadora persica): An Analytical study using Fourier-transform infrared spectroscopy and ultraviolet–visible spectrophotometer. J Int Oral Health [serial online] 2021 [cited 2021 Oct 26];13:258-66. Available from: https://www.jioh.org/text.asp?2021/13/3/258/318448
| Introduction|| |
Technological developments in the field of dental and oral health are increasingly advancing along with the emergence of the industrial revolution 4.0., This revolution shows a change in the use of traditional technology combined with modern technology, one of which is to improve oral health. One method to maintain oral health is by using miswak. Miswak (Salvadora persica) is able to remove stains and food sediments which contain microorganisms on the teeth surface. At present, miswak is freely sold in all world markets. However, there have not been many studies which focus on the content of active substances in miswak sold freely in the community.
The mouth is the main pathway for various energy sources of periodontal infection that can affect human health status., Systemic diseases that arise in the human body are often associated with poor oral conditions. Routine dental care can reduce the risk of periodontal disease and poor systemic disease conditions. In general, people use toothbrushes to clean buccal and lingual surfaces of teeth. On the contrary, the results of recent studies indicate that miswak can reduce the number of aerobic and anaerobic bacteria.
The chemical content of miswak can eliminate food debris on the surface of teeth, kill microorganisms, and function as an anti-inflammatory for the oral cavity. Miswak contains crystals that function as ingredients to whiten teeth and remove plaque and has now become a trend in South America and the Middle East, including Saudi Arabia, Asia, Africa, and Islamic countries. One factor that encourages people to use miswak is perceived behavioral control. It has gained popularity because of its low price and easy usage. Miswak can be utilized simply by biting and chewing one end of the stem to form fibers,, and a twig that has been soaked for several hours prior to usage produces soft fiber that is easy to chew. Cutting the tip of the miswak each time it is used enhances its maximum effect. Cutting the miswak before chewing it will release benzyl isothiocyanate.
In the current days, miswak has a variety of clean and healthy packaging on the market. The chemical content in miswak initiates scientists to develop it not only as a toothbrush, but also toothpaste. Toothpaste from miswak extract has now almost defeated the conventional toothpaste sales in the market. However, in general, miswak is marketed in the form of twigs, measuring 15–20 cm and 1–1.5 cm in diameter. Its small size and mint-like flavor makes miswak comfortable to use. Therefore, this research was conducted to analyze the content of various active substances in the varieties of miswaks which are sold freely in the public market.
| Materials and Methods|| |
This study used five miswaks that were freely chosen in traditional and online markets. The types that were chosen came from Saudi Arabia and Pakistan. The roots of miswak A and B were from Pakistan, whereas those of miswak C, D, and E were from Saudi Arabia. All miswaks were extracted using solvents through maceration method. The miswak extract was made using absolute ethanol, 96% ethanol, Aqua Bidest, and potassium bromide (KBr). Among the tools used in this research were sterile bottles, Whatman filter paper number 42, sample container, knife, rotary evaporator, tweezers, syringe, analytical scales, mortars, measuring flasks, and blenders.
Miswak skin was peeled and grated. The grated result was then aerated for 2 weeks until it dried. The dried miswak was then blended to form a fine powder. Eight grams of miswak powder was soaked with 80 mL of 96% ethanol (ratio 1:10) in a container. The miswak solution was then closed and left for 24 h. Next, the miswak extract was filtered using a filter paper and placed in a sterile bottle. Bottles containing miswak extract were stored in a refrigerator until the sample was ready for use. The extract later underwent an evaporation process with a ratio of 1:20 by dissolving 18 g of miswak extract with 360 mL of ethanol and then left for 24 h. After that, the extract was filtered and evaporated using an evaporator to produce a thick extract.
Samples were tested using optical techniques that were considered to be quite safe and did not damage the test sample. This study used three types of sample tests, namely, the powder sample test, liquid extract sample test, and the evaporated extract test. The samples were tested using Fourier-transform infrared (FTIR) spectroscopy to determine the active substances in powder miswak, whereas the UV–Vis method was used to determine the amount of active substance content based on the absorbance value produced. The active substances in this study were compounds that can be easily separated and bound to other compounds.
FTIR test of miswak powder
A total of 0.00325 g of miswak and 0.000325 g of KBr was crushed and ground in a mortar and then tested using FTIR. The ratio of miswak and KBr was 10:1.
FTIR test of miswak extract
The miswak extract was tested by adding 0.001 g of KBr in the testing medium and 2 drops or 0.05 cc of miswak extract.
FTIR test of evaporated miswak extract
An FTIR test on evaporated miswak extract was done using different concentrations, i.e. 100, 500, and 1000 ppm. These variation tests were aimed to study possibility to identify the concentration amounts of miswak extract that are mixed in toothpaste. The first process was mixing 0.001 g of KBr with two drops of miswak extract that had been evaporated at a concentration of 100 ppm. Subsequently, concentrations of 500 and 1000 ppm extracts were measured alternately using FTIR.
UV–Vis tests are conducted to determine the amount of active substance based on the result of FTIR by observing the absorbance values. Organic samples were tested using a spectrophotometer with wavelengths of 200–800 nm.
Miswak extract test
Miswak extract was diluted 75× and 25× using absolute ethanol solvent. The first test process was the blank test or background test. Next, a 10× dilution was carried out using a micropipette of 1000–100 micro, and then the sample was shaken together with 9 mL absolute ethanol. Seventy-five times dilution was done by taking 1.5 mL of sample from 10× dilution and then mixed with absolute ethanol up to 10 mL. The sample was shaken and then put into a 4 mL test cuvette for the UV–Vis testing. Twenty-five times dilution was done by dissolving 2.5 mL of sample and 10× dilution sample. Samples were diluted with absolute ethanol up to 10 mL. A total of 4 mL of sample was put into a cuvette and UV–Vis test was carried out.
Evaporated miswak extract test
In this test, 0.01 g of miswak extract that had been evaporated was diluted with 10 mL of absolute ethanol to make a concentration of 1000 ppm. Furthermore, 5 mL of the sample with a concentration of 1000 ppm was dissolved with 10 mL of absolute ethanol to form a concentration of 500 ppm. Lastly, 2 mL of 500 ppm sample concentration was diluted with 10 mL of absolute ethanol to make a sample concentration of 100 ppm. All samples were tested using a UV–Vis spectrophotometer.
There are several circumstances in which spectra were unreadable, as the case in FTIR measurements where the spectra cannot be read if the transmittance values are above 200 due to excessive KBr mixing. In contrast, the spectrum experiences “overshoot” on the UV–Vis measurements if the absorbance values are greater than 4, so that the resulting peak is not readable. That is why it is necessary to re-check UV–Vis spectra with various dilutions to obtain the highest absorbance peaks with a certain wavelength. Data analysis was done using Origin software to create data and display it in the form of research spectrum.
| Result|| |
Analysis of miswak powder FTIR test results
Similarities were found on the spectrum of each sample of miswak powder [Figure 1]. The next analysis was done using one of the spectra chosen at random, namely, Spectrum B.
The functional group in miswak powder type B showed that the phosphoric acid group and P-H ester strain became the dominant compound at wavenumber 2351 cm‒1 within the range of wavenumbers 2425-2325 cm‒1 [Figure 2] and [Table 1]. Compounds containing phosphorus atoms were found to be the active substances of the miswak plant. The function of phosphorus, together with calcium, forms a calcium phosphate compound that plays a role in the formation of human bones and teeth.
Analysis of the FTIR test results of miswak extract
The results of FTIR analysis showed the similarity of the five spectrum types of miswak. Compounds containing phosphorus atoms within the 2425-2325 cm‒1 wave range became the benchmark for every test. Therefore, the compounds that were in the region of the wavenumber were set as the comparison for the miswak extraction process. The spectrum of miswak B and miswak E extracts showed a low transmission valley in the wavenumber area of 2425-2325 cm‒1, which was a compound containing phosphorus atom [Figure 3].
The compound contained a phosphorus atom at wavenumber 867.96 cm‒1 with P-O groups and 430.01 cm‒1 with the P-Cl group. The function group did not appear in the miswak powder spectrum, but appeared when the miswak powder is extracted [Figure 4] and [Table 2].
Analysis of UV–Vis test for miswak extract
Spectrum cuts were only taken in areas of 200–250 nm for each 25× and 75× dilution of five miswak types [Figure 5].
Miswak B and miswak E had higher absorbance values than miswak A, miswak C, and miswak D at 25× and 75× dilutions. Absorbance values with 25× dilution were higher than those with 75× dilution [Table 3]. Therefore, the analysis will be focussed on two samples which had high absorbance values.
|Table 3: The absorbance value of miswak B and miswak E extracts with 75× and 25× dilutions|
Click here to view
Analysis of UV–Vis test results of evaporated miswak extract
At concentrations of 100, 500, and 1000 ppm, the spectra were cut from 250–350 nm [Figure 6]. This is because the peak produced was in the wavelength region of 250–350 nm.
|Figure 6: UV–Vis test results on miswak B and miswak E: (A) concentration of 100 ppm, (B) concentration of 500 ppm, (C) concentration of 1000 ppm|
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At a concentration of 1000 ppm, miswak E had a higher absorbance value than miswak B [Table 4]. The higher the concentration of miswak, the higher the absorbance value produced. Thus, even more active substances are absorbed. The miswak E sample had three peaks whereas the miswak B sample has only one peak. This was because miswak E underwent a molecular bond split after going through an evaporation process.
Analysis on the evaporated miswak extract FTIR test results
Sample B did not show uptake of phosphorus atom compounds at concentrations of 100, 500, and 1000 ppm [Figure 7]. The wavenumber had a fairly high transmission value and from the absence of the transmission valley, it can be stated that there was no absorption of compounds containing phosphorus at 2425-2325 cm‒1. Meanwhile, miswak E had a spectrum difference in the wavenumber 2425-2325 cm‒1 region.
|Figure 7: FTIR test results of evaporated miswak extracts at the concentrations of 100, 500, and 1000 ppm: (A) miswak B and (B) miswak E|
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Concentrations of 1000 ppm did not result in a valley in the region of phosphorus atom compounds, whereas concentrations of 100 and 500 ppm did absorb compounds containing phosphorus atoms. Miswak E had a low transmission in the phosphorus atom compound area; this indicated an absorption with a concentration of 1000 ppm. This showed that with the same concentration, the two samples did not have the same spectrum in the process of absorption of active substances. In miswak B, there was no spectrum that showed uptake in the wavenumber 2425-2325 cm‒1, which was compound containing phosphorus atoms. In the phosphoric acid compound with P-H functional group, the hydrogen element was evaporated. This removed the P-H bond and it ceased to produce P-H bond [Figure 8] and [Table 5].
Miswak E sample had a transmission valley in the wavenumber range of 2425-2325 cm‒1. Valley transmission showed the absorption of compounds containing phosphorus atoms. The miswak E sample had a strong intermolecular bond; hence the phosphoric acid compound with the P-H group did not split when it passed through the evaporation process [Table 6]. In this test, the miswak extract could be applied to toothpaste. The optimum concentration of this test was 1000 ppm for miswak E [Figure 9].
|Table 6: The content of miswak E extract compound after being evaporated|
Click here to view
| Discussion|| |
The evaporation process in miswak extracts resulted in the differences within the spectrum of compounds. The evaporated miswak extract had a functional group that did not appear in the spectrum of miswak powder and miswak extract. Clusters in the evaporated miswak extract include: (1) C = C alkyne with aliphatic hydrocarbon compounds in 2127.48 cm‒1 wave; (2) Si-OC groups with compounds containing silico atoms in 1110.99 cm‒1 wave; (3) group P = S with compounds containing phosphorus atoms that bind to sulfur atoms in 823.60 cm‒1 wave. These compounds appeared when the miswak had gone through the process of extraction and evaporation.
The extraction process was carried out to take the active substances in miswak, whereas the evaporation process aimed to find out the pure substances contained in miswak. These compounds did not appear in the miswak powder spectrum because of the high oxygen and hydrogen content which masked other compounds that were not dominant in the miswak. Some chemical compounds contained in miswak include: sulfur, fluoride, butanediamine, and N-benzyl-2-phenylacetamide., These compounds can kill Gram-positive and Gram-negative bacteria. Previous studies mentioned that the miswak ethanol extract can inhibit the growth of Staphylococcus aureus resistant multiantibiotic at a concentration of 25% w/v in vitro.
Test results showed that miswak E had a better ability to maintain active substances compared with other four miswak types. This is based on the absorbance value of the evaporation results. The active substances of each miswak sample were in the wavenumber area of 2425-2325 cm‒1, this indicated that they were in the P-H group with compounds containing phosphorus atoms. In the human body, phosphorus and calcium can form calcium phosphate compounds that are important in the formation of bones and teeth. Miswak also contains alkaloids and nitrogen with varying structural patterns, including salvadorine, salvadourea, and benzyl isothiocyanate. Apart from maintaining oral health, miswak is considered a traditional medicine for several diseases, as researches mentioned that it has the ability to reduce cholesterol and plasma LDL. It can also inhibit ulceration and can be both an anticonvulsant and analgesic.,,
This study used FTIR to analyze complex molecules because it has a large application range. Applications of FTIR spectroscopy can be used as quantitative analysis of complex mixtures in liquid, solid, or gaseous forms. The peaks in the FTIR test indicate unabsorbed molecular transmissions, whereas the absorbed molecules are indicated by the valley of a graphic peak. Infrared radiation with a frequency less than 100 cm‒1 or with a wavelength of more than 100 μm can be absorbed by the molecule and converted into molecular rotational energy, whereas infrared radiation with a frequency in the range of 10,000 cm‒1 up to 100 cm‒1 or with wavelengths of 1–100 μm is absorbed by the molecules and converted in molecular vibration energy. In addition, quantitative molecular measurements apply the UV–Vis spectrum. Measurement of the concentration of the analyte in a solution can be determined by measuring the absorbance at a specific wavelength using the law of Lambert and Beer.
The miswak E sample shows several peaks through the evaporation process, which is indicated by the presence of more than one electron transition that is different from the active substance in miswak E. These electronic transitions occur because atoms or molecules absorb electromagnetic radiation. Electronic transition is the transfer of electrons in orbitals from lower energy to higher energy levels. All molecules can absorb radiation in the UV–Vis region because they contain electrons which can be excited to a higher energy level.
| Conclusion|| |
From the results of the study, it can be concluded that the miswak on the market contains an active material in the form of phosphoric acid which consists of phosphorus atoms which are useful in the formation of teeth and bones. Miswak E has a higher absorbance value and amount of active substance than the other four types of miswak. It is hoped that the Raman Spectroscopy test can be used in further research to determine the active content of miswak because it is considered more accurate.
The authors acknowledge Physics Laboratory, Faculty of Mathematics and Natural Sciences, Udayana University, Jimbaran‑Bali, Indonesia.
Financial support and sponsorship
This research was funded by Faculty of Dental Medicine, Universitas Airlangga.
Conflict of interest
There are no conflicts of interest.
Study conception (ATJ, AN, ALF), data collection (ATJ, AN, HS, TB), data acquisition and analysis (AN, HS, TB), data interpretation (ATJ, AN, TB), and manuscript writing (ATJ, AN, HS, ALF, TB).
Ethical policy and institutional review board statement
This study did not use a clinical trial. This study has received ethical approval from the Dental Medicine Health Research Ethical Clearance Commission of Universitas Airlangga (122/HRECC.FODM/IV/2019), in accordance with the World Medical Association Declaration of Helsinki.
Patient declaration of consent: (If In-vivo Study / Case reports)
In this study, there were no patients and only use the miswak to examine the contents of the siwak.
Data availability statement
The data is available on request to author ([email protected]).
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]