JKPK (JURNAL KIMIA DAN PENDIDIKAN KIMIA).
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No.
1, 2024
Chemistry Education Study Program.
Universitas Sebelas Maret https://jurnal.
id/jkpk ISSN 2503-4146 ISSN 2503-4154 .
PHYTOCHEMICAL SCREENING AND ANTIBACTERIAL
ACTIVITY OF ETHANOLIC EXTRACTS FROM Delonix regia
AGAINST LABORATORY STRAINS OF DIARRHEAL BACTERIA
Yeyen Susana Senge1.
Irfan Mustafa2.
Anna Safitri1,3* Department of Chemistry.
Faculty of Mathematic and Natural Sciences.
Brawijaya University.
Malang.
East Java,Indonesia Department of Biology.
Faculty of Mathematic and Natural Sciences.
Brawijaya University.
Malang.
East Java Indonesia Research Center of SMONAGENES (Smart Molecules of Natural Genetic Resource.
Brawijaya University.
Malang.
East Java Indonesia
ARTICLE INFO
ABSTRACT
Keywords:
Delonix regia.
FTIR.
LC-MS/MS.
The present study evaluates the antibacterial efficacy of ethanolic extracts from Delonix regia leaves against diarrhea-inducing bacteria Escherichia coli and Salmonella typhimurium.
Preliminary phytochemical screening revealed that D.
regia leaves comprise flavonoids, alkaloids, saponins, tannins, phenolics, and terpenoids.
Fourier Transform Infrared Spectroscopy (FTIR) analysis identified various functional groups in the D.
regia leaf extract, including O-H.
CArticle History:
C=O.
C=C.
C-C.
C-O, and C-O-C.
Liquid Chromatography-Mass Received: 2024-02-27 Spectrometry/Mass Spectrometry (LC-MS/MS) analysis further Accepted: 2024-04-20 confirmed the presence of 16 distinct compounds comprising amino Published: 2024-04-23 acids, alkaloids, phenolics, flavonoids, terpenoids, anthraquinones, nacyl pyrrolidines, and fatty acids.
The disc diffusion method (Kirby*Corresponding Author Baue.
was employed for the antibacterial tests.
The extracts of D.
Email: a.
safitri@ub.
leaves at concentrations of 25%, 50%, 75%, and 100% generated doi:10.
20961/jkpk.
inhibition zones measuring 5.
26 mm, 6.
37 mm, 7.
27 mm, and 10.
18 mm against E.
coli, and 5.
05 mm, 7.
01 mm, 8.
77 mm, and 10.
04 mm against typhimurium, respectively.
The commercial antibiotic ciprofloxacin .
positive contro.
produced inhibition zones of 30.
02 mm for E.
coli and 28 mm for S.
The negative control, consisting of 10% A 2024 The Authors.
This open- ethanol, showed no inhibitory effect on bacterial growth.
These findings access article is distributed indicate that the ethanolic extract of D.
regia leaves possesses under a (CC-BY-SA Licens.
antibacterial properties against E.
coli and S.
It is likely that secondary metabolite compounds, such as flavonoids and phenolics, contribute significantly to the observed antibacterial activity How to cite: Y.
Senge.
Mustafa.
Safitri, , "Phytochemical Screening and Antibacterial Activity of Ethanolic Extracts from Delonix regia Against Laboratory Strains of Diarrheal Bacteria," Jurnal Kimia dan Pendidikan Kimia
(JKPK),
50-68,
Available:
http://dx.
org/10.
20961/jkpk.
these species are utilized by the traditional INTRODUCTION Indonesia is abundantly endowed with natural resources, supporting the growth remedies .
According to the World Health of nearly all plant types .
It is estimated that Organization (WHO), 80% of populations in there are approximately 90,000 plant species developing countries rely on medicinal plants in Indonesia, of which 9,600 are recognized for traditional medicine practices .
, and for their medicinal properties.
About 300 of Indonesia is prominent among these nations.
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One notable example of a medicinal plant for its antimalarial activity .
The seeds, used in traditional treatments in Indonesia is roots, stems, and leaves are all documented Delonix regia.
to exhibit antibacterial activities .
, 14, .
Delonix regia, commonly known as The phytochemical content of D.
regia is flamboyant, is a flowering legume within the Fabaceae family and the Caesalpinioideae flavonoids, terpenoid saponins, phenolic subfamily, originally from Madagascar .
compounds, carbohydrates, tannins, and regia plants are prevalent across most glycosides .
Similarly, the plantAos leaves, subtropical and tropical regions .
In East roots, and stems contain a blend of Nusa Tenggara (NTT), particularly in Kupang flavonoids, saponins, steroids, alkaloids, and City, .
, roadsides, city parks, residential yards, and specifically rich in flavonoids, alkaloids.
Despite their widespread presence, tannins, saponins, phenolics, and glycosides public awareness of the health benefits of D.
regia plants could be improved, leading to underutilization in medicinal applications.
These plants are commonly regarded as roadside vegetation providing shade or used However, potential of D.
regia, with various plant parts such as leaves, flowers, bark, stems, and seeds effectively treating various ailments .
ethanol extract of D.
regia leaves inhibited the Staphylococcus Klebsiella bacteria, achieving inhibition zones of 12 mm and 19 mm, respectively .
Further research by Gautam and Sumet .
revealed that the methanol extract of D.
leaves, rich in flavonoid content, effectively inhibited the growth of S.
Escherichia coli.
Pseudomonas aeruginosa, and Bacillus subtilis, with inhibition zones measuring Delonix regia (D.
flowers are utilized in treating various ailments, including arthritis, diabetes, pneumonia, and malaria, and serve roles as antioxidants, anticancer, and antibacterial agents .
, .
The leaves are recognized for their cardioprotective damage in ischemic heart disease (IHD), and exhibiting significant antioxidant and antiinflammatory properties .
, 9, .
The stem Previous studies have shown that the activities .
, with the bark specifically noted 00 mm, 23.
67 mm, 19.
67 mm, and 24.
These antibacterial properties suggest that D.
regia leaves could be a viable alternative for combating diseases caused by bacteria, such as diarrhea.
Diarrhea, a prevalent condition caused by infections in the human digestive tract .
, involves multiple biological agents, including viruses and bacteria, and is a significant cause of mortality, especially among children .
The use of D.
regia leaves in treating pathogenic bacteria responsible for infections in the safitri et al.
Phytochemical Screening and Antibacterial .
digestive tract, particularly Escherichia coli Salmonella underexplored and merits further research.
Salmonella Given this context, this study aims to evaluate the antibacterial efficacy of Delonix (D.
pathogenic bacterial strains that cause typhimurium is a major enteric pathogen diarrhea, specifically Escherichia coli (E.
infecting humans and animals.
Infection occurs through consuming contaminated Furthermore, this research will food or drink, enabling the pathogen to characterization of the chemical constituents .
in the ethanol extract of D.
regia leaves.
Symptoms which may underpin its biological activity as Salmonella fever, and diabetes .
Additionally.
employed for characterization will involve is notably the most frequent bacterial cause qualitative phytochemical screening and of diarrhea in children under five, primarily transmitted through ingesting contaminated Transform Infrared Spectroscopy (FTIR) and food and drinks, exposure to unsanitary Liquid
Chromatography-Mass
Spectrometry/Mass Spectrometry The Fourier
(LC-
MS/MS).
These techniques will be used to handling of animal products .
abdominal pain, nausea, vomiting, acute (S.
Indonesia, diarrhea remains a significant health challenge due to its role in causing malnutrition and mortality .
One common treatment approach involves using antibiotics to manage diarrhea resulting from bacterial However, the rise of antibiotic resistance poses a severe threat to global health, necessitating the discovery of new analyze the structural properties and identify the metabolite profile of the ethanol extract.
The findings could highlight D.
regia leaves as a valuable source of new antibacterial infections caused by pathogenic bacteria linked to diarrhea METHODS Materials and Tools antibacterial agents.
This issue is particularly Delonix regia leaves were collected acute with gram-negative bacteria, which from Pukdale village in Kupang City.
East exhibit greater resistance due to their Nusa Tenggara (NTT).
Indonesia.
Selection complex cell wall structures than gram- criteria for the leaves included maturity and positive bacteria.
Consequently, there is an freshness, and the collection was conducted in the afternoon to avoid high sunlight substances that can effectively combat these intensity and ambient temperature.
The resistant strains.
Natural sources, such as chemicals used in this study included ethanol plant extracts, offer promising alternatives for .
%), distilled water.
Mayer's reagent, developing such agents .
Dragendorf's reagent.
Bouchardat's reagent, concentrated HCl.
Mg powder.
FeCl3, 1% JKPK (JURNAL KIMIA DAN PENDIDIKAN KIMIA).
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FeCl3, 0.
9% NaCl, nutrient agar (Oxoi.
, resulting in a concentrated extract.
The blank disks (Oxoi.
, and antibiotic disks extract was weighed and stored in vials for .
further analysis.
The yield percentage was The involved were Salmonella typhimurium and calculated using the following formula:
Escherichia coli.
% Yield =Sample weight x 100 % Extract weight
Instrumentation for the research
UV-VIS
(Shimadz.
, a Fourier-transform infrared (FTIR) spectrophotometer type SHIMADZU This formula helps determine the efficiency of the extraction process in terms of the amount of extract obtained relative to the initial weight of the plant material used.
8400S, and liquid chromatography-tandem (LC-MS/MS).
High- Phytochemical Screening of Ethanolic resolution mass spectrometry analysis was Extract of D.
regia Leaves performed using an ultra-performance liquid Phytochemical screening was conducted chromatography (UPLC) system, specifically to identify and confirm the presence of the ACQUITY UPLCA H-Class System bioactive compounds in the ethanolic extract (Waters.
USA) with MS Xevo G2-S QTof of Delonix regia leaves.
This process is (Waters.
USA).
The analyses employed a C18 column .
8 m, 2.
1x100 mm.
ACQUITY therapeutic properties of the extract.
UPLCA HSS.
Waters.
USA) at a room prepared solution of 250 mg of the D.
temperature of approximately 25AC and a leaf extract in 50 mL of 96% ethanol served column temperature of 50AC.
as the basis for various qualitative tests to Extraction of D.
regia Leaves The leaves of Delonix regia were detect specific classes of phytochemicals.
Flavonoids harvested, washed under running water, and To test for flavonoids, a sample of the left to air dry for five days while being shielded from direct sunlight.
Once dried, the leaves were ground into a fine powder using a The extraction of D.
regia leaves employed the maceration method, using a ratio of 1:4 .
eaf powder to solven.
Specifically, with periodic stirring, 250 g of D.
regia leaf powder was macerated in 1000 mL of 96% ethanol for three consecutive 24-hour After each period, the mixture was filtered using filter paper and compressed with a hydraulic press to extract the liquid.
The filtrate was then evaporated using a water bath set at 70AC to remove the ethanol, regia leaf extract solution .
mL) was heated for 5 minutes to enhance the reactivity of potential flavonoids.
After heating, 1 mL of hydrochloric acid (HC.
and a small quantity .
05 m.
of magnesium powder were added to the solution.
The presence of flavonoids is typically indicated by the development of red, yellow, or orange colors in the reaction These color changes result from the complexation of the flavonoids with the added characteristic of this phytochemical group .
safitri et al.
Phytochemical Screening and Antibacterial .
Alkaloids For alkaloid detection, 250 mg of the regia leaves extract was mixed with 1 mL of 2N hydrochloric acid and 9 mL of distilled water and then heated for 2 minutes to activate the alkaloids.
After cooling, the mixture was filtered, and 1 mL of the filtrate was transferred into three separate test tubes for testing with different chemical reagents.
The first tube received a few drops of Mayer's reagent, typically forming a white or yellow precipitate if alkaloids are present.
The second tube was treated with Bouchardat's To test for tannins in the Delonix regia leaves extract, 1 mL of the extract solution was treated with 1% ferric chloride (FeCl.
The presence of tannins is typically indicated by the formation of green, blue, or black coloration in the solution.
These color changes occur due to the complexation between tannins and the ferric ions, demonstrating the ability of tannins to bind and precipitate metals, a property that contributes to their astringency and potential health benefits .
Phenolics reagent, which resulted in a brown-to-black precipitate, and the third tube received Dragendorff's reagent, forming a yelloworange precipitate.
The test is considered positive for alkaloids if at least two reagents form a precipitate, indicating a substantial presence of alkaloid compounds in the extract .
, .
Saponins The saponin content was assessed by adding 1 mL of the D.
regia leaves extract solution to 5 mL of distilled water, followed by vigorous shaking for 10 seconds.
The presence of saponins is evidenced by To detect phenolic compounds, 1 mL of the D.
regia leaves extract solution was mixed with a few drops of FeCl3.
The presence of phenolics is confirmed by the appearance of colors ranging from green, red, purple, blue, dark blue, and bluish-black to dark green.
These color variations result from forming phenolic-Fe.
complexes, which differ based on the specific types of phenolic compounds present in the extract.
The 10 minutes.
This foam formation occurs due to the soap-like properties of saponins, which lower the surface tension of the liquid.
The foam's stability, even after adding 2N hydrochloric acid, which does not cause the foam to dissipate, further confirms the presence of saponins in the extract .
Tannins chelating capacities .
Terpenoids forming a stable foam layer measuring 1 to 10 cm in height that persists for approximately terpenoids, 2 mL of the D.
regia leaves extract solution was mixed with 2 mL of chloroform, followed by adding a few drops of concentrated sulfuric acid (H2SO.
The development of a reddish-brown precipitate upon this addition is indicative of terpenoids.
This color change typically results from the acid-based reaction between terpenoids and JKPK (JURNAL KIMIA DAN PENDIDIKAN KIMIA).
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rearrangements and complexation within the desolvation processes were set at 100AC and terpenoid molecules .
350AC, respectively.
The chromatograms and mass spectra obtained from UPLC-MS/MS Characterization of the Ethanolic Extract of D.
regia Leaves FTIR (Fourier Transform Infrared Spectroscop.
The ethanolic extract of Delonix regia were analyzed using MassLynx Version 4.
Data were recorded, including each detected peak's peak areas and m/z values.
These data were then cross-referenced and leaves was characterized using FTIR to interpreted using various chemical databases identify the functional groups present in the such as PubChem.
ChemSpider.
HMDB, and For this analysis, the extract was CFM-ID to identify the chemical constituents mixed with potassium bromide (KB.
and present in the extract .
, .
compressed into a circular pellet with a thickness of 1 mm.
This pellet was then Antibacterial Activity Test placed in the sample holder of the FTIR The medium used in this study was The analysis was conducted nutrient agar (NA).
Initially, 7 g of NA powder over a wavenumber range of 4000-400 cm-1.
was added to an Erlenmeyer flask, dissolved The in 250 mL of distilled water, and heated with detailed information about the types of constant stirring until the solution was chemical bonds and functional groups within homogeneous and boiling.
Then, 7 mL of the the sample, such as hydroxyl, carbonyl, and solution was transferred to a sterile test tube, sealed with cotton, wrapped in aluminum foil.
FTIR compound classes present in the extract.
LC-MS/MS (Liquid Chromatography-Mass Spectrometry/Mass Spectrometr.
For the LC-MS/MS analysis, 10 mg of D.
regia leaf extract was dissolved in 10 mL and sterilized using an autoclave at 15 psi and 121 AC for 15 minutes.
After sterilization, the test tube was inclined to allow the media to solidify in a slanted position, which was then used to rejuvenate the test bacteria.
of methanol.
A microsyringe was used to draw 5 L of this solution, which was injected into the sample area and UPLC column.
The Subculture of Test Bacteria Pure Salmonella liquid chromatography analysis employed a typhimurium and Escherichia coli were each mobile water phase with 5 mM ammonium transferred using a sterile loop needle and formate (A) and acetonitrile with 0.
05% formic streaked aseptically onto the solid slanted acid (B).
The flow rate was maintained at 0.
agar media in a zig-zag pattern.
The cultures mL/min over 23 minutes, with an injection were then incubated for 24 hours at 37 AC.
volume of 5 L.
Mass spectrometry was (ESI) source operating in positive ionization Preparation Test Bacterial Suspension The first step in preparing the mode across a mass range of 50Ae1200 m/z.
bacterial suspension involved creating a The temperatures for the source and the 9% NaCl solution.
This was done by analyzed using an electrospray ionization safitri et al.
Phytochemical Screening and Antibacterial .
9 g of NaCl in a 100 mL impregnated with ciprofloxacin acted as the volumetric flask filled with distilled water.
Af.
ter homogenization, 9 mL of this solution diameter of the inhibition zones formed was transferred to a test tube and sterilized in around the discs was measured using a an autoclave at 15 psi and 121 AC for 15 caliper and recorded in millimeters .
In the second step.
Salmonella subtracting the diameter of the disc .
to typhimurium and E.
coli bacteria, previously account for the actual zone of inhibition.
The rejuvenated on nutrient agar, were taken experiment was conducted in triplicate .
using a sterile loop and transferred into a test Statistical Analyses tube containing 9 mL of the sterile 0.
9% NaCl then measured at 600 nm using a UV-vis spectrophotometer, aiming for a cell density 6, equivalent to approximately 106 Post-incubation.
Data analysis was conducted using The suspension was homogenized using a vortex.
The optical density (OD) was the IBM SPSS software, version 29.
Initially, a normality test was applied using the Kolmogorov-Smirnov method to determine the data distribution.
If the data were normally distributed, a One-Way ANOVA was utilized CFU/mL.
to assess the significance of the differences Antibacterial Activity Test among treatments, setting the confidence level at 95% ( = 0.
After the ANOVA, the assessed using the disc diffusion method Tukey HSD (Honestly Significant Differenc.
(Kirby Baue.
Concentrations of D.
post-hoc test was performed to pinpoint the leaves extract tested were 25%, 50%, 75%, differences between each treatment group.
and 100%.
Initially, 5 g of D.
regia leaves Experimental results are expressed as mean extract was dissolved in 5 mL of 10% ethanol to prepare the 100% concentration solution.
significance was established at p-values less This solution was then serially diluted to 05, indicating meaningful differences achieve 25%, 50%, and 75% concentrations.
between the experimental groups.
This Approximately 15Ae20 mL of nutrient agar was approach ensures a rigorous data analysis, poured into each sterile petri dish and providing a reliable basis for interpreting the allowed to solidify.
Each bacterial suspension efficacy of the treatments under study.
The Standard Deviation (SD).
Statistical of Salmonella typhimurium and E.
coli was then evenly swabbed over the surface of the solidified NA using a sterile cotton swab.
Sterile paper discs .
mm in diamete.
were soaked in each concentration of the D.
leaves extract solution for 30 minutes, placed onto the agar surface using sterile tweezers, and incubated at 37 AC for 24 hours.
A sterile paper disc soaked in 10% ethanol served as RESULTS AND DISCUSSION Phytochemical Screening Results of Ethanolic Extract of D.
regia Leaf Delonix regia leaves were extracted using the maceration method with 96% ethanol as the solvent.
Ethanol is widely regarded as a universal solvent due to its ability to dissolve almost all secondary metabolite compounds and its relatively low JKPK (JURNAL KIMIA DAN PENDIDIKAN KIMIA).
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toxicity compared to other organic solvents.
identifying such metabolites.
Understanding From the maceration process, 18.
88 g of a the phytochemical components present in the dark green ethanolic extract was obtained from D.
regia leaves, yielding 7.
biological and pharmacological effects of the The plant .
The observed color changes in Table 1 confirmed flavonoids, alkaloids, screening to analyze its content of secondary saponins, phenolics, tannins, and terpenoids in the ethanolic extract of D.
regia leaves.
included flavonoids, alkaloids, saponins.
These results are consistent with previous phenolics, tannins, and terpenoids.
Color studies, which identified flavonoid, alkaloid, changes indicated the presence of these saponin, phenolic, tannin, and terpenoid compounds upon reaction with specific compounds in D.
regia leaf extracts .
, .
The standard reagents, a common method for Table 1.
Phytochemical qualitative screening results of ethanolic extract of D.
regia leaves Secondary Metabolites Flavonoids Observation Result Alkaloids Saponins Tannin Phenolic Terpenoids Description: ( ) = Contains these phytochemicals, (A.
= Does not contain these phytochemicals.
safitri et al.
Phytochemical Screening and Antibacterial .
Fourier-transform infrared spectroscopy extract of D.
regia leaves is rich in phenolic (FTIR) was utilized to characterize further the compounds .
, underscoring its potential Delonix regia leaves extract by identifying the therapeutic properties.
functional groups present.
The FTIR analysis.
While conducted over a wavenumber range of 4000- 400 cm-1, revealed several absorption peaks, insights into the functional groups present in each corresponding to different functional the Delonix regia leaves extract, it alone groups, as depicted in Figure 1 and detailed in Table 1.
Therefore, further analysis using The spectrum displayed a significant Fourier-transform
(FTIR)
peak at 3283.
14 cm , indicative of an alcohol chromatography-tandem mass spectrometry or phenol hydroxyl group (O-H).
Peaks at (LC-MS/MS) 31 cm-1 and 2852.
42 cm-1 were associated with aliphatic C-H functional characterization, offering intricate details A peak suggested the presence of regarding the composition, structure, and cm-1, identification of compounds within the extract.
The According to the chromatogram results depicted in Figure 2, 16 primary compounds 06 cm-1 were attributed to alkene have been identified in the D.
regia leaves These compounds were further indicated the presence of an aromatic ring (C- analyzed using several databases, including C), while peaks at 1239.
38 cm-1 and 1041.
PubChem.
ChemSpider.
HMDB, and CFM- cm-1 suggested the presence of alcohol (C-O) ID, which revealed their chemical nature as and ether (C-O-C), respectively.
Additionally, amino acids, alkaloids, phenolics, flavonoids, the absorption wavelengths at 832.
91 cm -1 38 cm-1 were consistent with acylpyrrolidines, and fatty acids, as listed in aromatic rings (C-H).
Table 3.
The polyphenol group, particularly C=O absorption peaks at 1607.
34 cm groups (C=C).
A peak at 1446.
18 cm The spectral interpretation confirms LC-MS/MS flavonoids and phenolics, emerged as the the presence of phenol hydroxyl groups, alkanes, aldehydes, alkenes, aromatic rings, indicating their prevalence in the extract as alcohols, and ethers in the D.
regia leaves evidenced by the metabolite data in Table 3.
Notably, the characteristic absorption This detailed analysis underscores the band at 3283.
14 cm , associated with O-H complex biochemical composition of the D.
stretching, underscores the presence of regia leaves extract, highlighting its potential hydroxyl groups, a hallmark of phenolic for various pharmacological applications.
This suggests that the ethanolic JKPK (JURNAL KIMIA DAN PENDIDIKAN KIMIA).
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Figure 1.
FTIR spectrum of D.
regia leaves extract Table 2.
Interpretation results of the FTIR spectrum of D.
regia leaves extract Wavenumber .
31 and 2852.
34 and 1516.
91 and 717.
Functional Group O-H Stretching C-H Stretching C=O Stretching C=C Stretching C-C Stretching C-O Stretching C-O-C Stretching C-H Stretching Compound Class Phenols Alkanes Aldehyde Alkene Aromatic Alcohol Ethers Aromatic safitri et al.
Phytochemical Screening and Antibacterial .
Figure 2.
UPLC-QToFMS/MS chromatogram of D.
regia leaves extract Table 3.
Data from UPLC-QtoFMS/MS chromatogram interpretation results of D.
regia leaves Retention Time (RT) Peak Area
(%)
Formula Measured mass .
Name Compound
C4H10N3O2
C8H10N
C9H7O2
C27H31O15
C15H11O6
C13H21O
C15H17O7
C22H25O9
C20H19O9
C19H19O7
C18H29O
3-Guanidinopropanoic 2,3-Dihydro-1H-indole Coumarin Kaempferol 3-rhamnoglucoside Kaempferol Beta-Ionone Hydroisoflavone B 3-Methoxynobiletin 5-Hydroxy-3,3',7,8tetramethoxy-4',5'methylenedioxyflavone Retusin .
Laurophenone C21H42NO
C23H46NO
C17H27O2
C10H13O2
C40H55
Antibacterial Activity 1-.
Nonadecanoic acid 3-Methoxy-5-pentyl-2prenylphenol Eugenol Echinenone Group Amino acid Alkaloids Phenolic Flavonoids Flavanoids Terpenoids Flavonoids Flavanoids Flavanoids Flavanoids Phenylpropa Nacylpyrrolidin Fatty acid Phenolic Phenolic Carotenoids Additionally, a 10% ethanol solution served Antibacterials are substances capable as the negative control to evaluate any of combating pathogenic bacteria by either potential antibacterial effects of the solvent killing them or inhibiting their metabolic on the growth of E.
coli and S.
activity, thus mitigating their deleterious The results indicated that the D.
effects within a biological environment .
leaf extract effectively inhibited the growth of this study.
Delonix regia leaf extract was both E.
coli and S.
typhimurium, as evidenced tested at various concentrationsAi25%, 50%, by the clear zones of inhibition observed 75%, and 100%Aito determine the most around the paper discs.
The data on the effective concentration for inhibiting the average diameters of these inhibition zones growth of Escherichia coli and Salmonella for each concentration are detailed in Table 4 (Figures 3 and .
This data supports the The concentration was assessed by comparing the diameter of the inhibition zones formed possesses significant antibacterial properties around the paper discs soaked in the extract and is effective across various concentrations solutions against those formed around a disc against these specific bacterial strains.
soaked in the positive control, ciprofloxacin.
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Figure 3.
Antibacterial activity results in test of D.
regia leaves ethanolic extract against E.
coli (A).
Concentrations 100%, 75%, 50%, and 25%, replication 1, 2, and 3.
(B) Control .
and control Ae .
% ethano.
, replication 1, 2, and 3.
Figure 4.
Antibacterial activity results test of D.
regia leaves ethanolic extract against S.
thypimurium (A) Concentrations 100%, 75%, 50%, and 25%, replication 1, 2 and 3.
(B)
Control .
and control Ae .
% ethano.
, replication 1, 2 and 3.
safitri et al.
Phytochemical Screening and Antibacterial .
Table 4.
The diameter of inhibition zones of D.
regia leaves ethanolic extract Sample Concentration (%) Mean Inhibition Zone Diameter .
A SD Escherichia coli Control Control Ae 26 A 0.
37 A 0.
27 A 0.
18 A 0.
02 A 2.
Salmonella 05 A 0.
01 A 0.
77 A 0.
04 A 0.
28 A 1.
Category Medium Medium Medium Strong Very strong According to the categorization in .
, rings can intercalate or form hydrogen bonds the antibacterial inhibition zones are grouped with the nucleic acids, inhibiting bacterial into four categories: diameters of inhibition nucleic acid production .
, .
zones less than 5 mm are categorized as In addition to flavonoids, phenolic weak, 5Ae10 mm as medium, greater than 10Ae compounds in D.
regia leaf extract, such as 20 mm as strong, and over 20 mm as very coumarin, have demonstrated antibacterial Coumarin targets the B subunit of antibacterial activity of D.
regia leaf extract DNA gyrase in bacteria, preventing ATPase against E.
coli and Salmonella typhimurium at activity and hindering DNA supercoiling, 25%, 50%, and 75% is classified as medium.
contributing to its antibacterial properties .
In comparison, it is classified as strong at a Additionally, eugenol, belonging to the phenol concentration of 100%.
This indicates that higher concentrations of the antibacterial phenylpropanoid, has been documented to material result in larger inhibition zones, disrupt the cytoplasmic membrane of gram- aligning with prior findings that suggest the negative bacteria, leading to structural cell greater the concentration of an extract, the changes and leakage of cellular contents, more bioactive components it contains, thus underscoring its antibacterial mechanism enhancing the inhibition zone diameter .
Based Research supports the notion that In the negative control, which utilized flavonoid compounds possess antibacterial 10% ethanol, no inhibition zones were Specifically, kaempferol has been observed around the paper discs for the two test bacteria.
This confirms that the 10% flavonoid, particularly against E.
coli, where it ethanol used as a solvent does not possess inhibits the enzyme DNA gyrase, a critical antibacterial activity.
Conversely, the positive agent in bacterial replication and DNA strand tension relief during DNA replication .
The significant antibacterial efficacy, producing antibacterial efficacy of flavonoids is often inhibition zones measuring 30.
02 mm against attributed to their chemical structure, notably coli and 28 mm against Salmonella the presence and position of methoxyl groups typhimurium, categorizing it within the "very at C-8 in ring A and hydroxyl groups at strong" inhibition range.
Ciprofloxacin, a position 3 in ring C.
Furthermore, flavonoid B fluoroquinolone class antibiotic, is known for JKPK (JURNAL KIMIA DAN PENDIDIKAN KIMIA).
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its bactericidal properties and its ability to typhimurium at 0.
> 0.
, confirming inhibit both gram-positive and gram-negative Subsequent analysis using one-way ANOVA Enterobacteriaceae family such as E.
showed significant results with a 0.
< Salmonella spp.
Shigella spp.
, and Neisseria .
It acts by inhibiting bacterial DNA These findings corroborate that gyrasesAitopoisomerase IVAi both the ethanol extracts of D.
regia leaves at disrupting DNA replication, causing DNA various concentrations and the positive damage, and ultimately leading to cell death controls are effectively inhibitory against the .
growth of E.
coli and S.
for both The average diameter of the inhibition zones reported in Table 4 is lower than those found in previous studies.
This discrepancy could be attributed to several factors, primarily the nature of the test bacteria.
and Salmonella typhimurium are gramnegative protective three-layered barrier.
The critical phospholipids, lipopolysaccharides (LPS), and proteins, notably contributes to bacterial resistance against antibacterial substances.
The membrane and the enzymatic activity in the periplasmic space can degrade external At the same time, the negatively charged LPS protects the bacterial cells against antibacterial agents .
, .
Other influencing factors include the metabolic activity and inherent sensitivity of the bacteria, as well as the concentration of the treatment and the type of solvent used, which affect the solubility and efficacy of the active compounds .
The statistical analysis indicated that the inhibition zones observed are normal as p > 0.
Homogeneity tests revealed consistent data for E.
coli with a significance value of 0.
> 0.
and for Salmonella
CONCLUSION
The conducted in this study demonstrate that Delonix regia leaf extract can effectively inhibit the growth of E.
coli and Salmonella It was observed that the higher the concentration of the D.
regia leaves extract, the larger the inhibition zone formed This attributable to the rich content of bioactive The antibacterial properties of the D.
regia leaf extract are significantly influenced by the secondary metabolites present in the leaves.
Characterization flavonoids and phenolics, as prevalent in the regia leaves extract and crucial in inhibiting bacterial growth.
Phytochemical screenings further confirmed the presence of flavonoids, alkaloids, saponins, tannins, and reinforcing the therapeutic potential of D.
regia leaves.
ACKNOWLEDGMENT
This research was supported by an safitri et al.
Phytochemical Screening and Antibacterial .
internal research grant from the Faculty of .
Suhane.
Shrivastava, and Singh.
AuGulmohar ornamental plant with medicinal uses,Ay 245 J.
Pharmacogn.
Phytochem.
, vol.
5, no.
6, pp.
245Ae 248, 2016.
Bin Rahman et al.
AuA multi-directional exploration of phytochemicals and bioactivities of flower extracts from Delonix regia (Bojer ex Hook.
) Raf.
Cassia fistula L.
and Lagerstroemia speciosa L.
,Ay Biochem.
Biophys.
Reports, vol.
24, no.
September, p.
doi: 10.
1016/j.
Ebada et al.
AuCharacterization of Delonix regia FlowersAo Pigment and Polysaccharides: Evaluating Their Antibacterial.
Anticancer, and Antioxidant Activities and Their Application as a Natural Colorant and Sweetener in Beverages,Ay Molecules, vol.
28, no.
7, pp.
1Ae19, doi: 10.
3390/molecules28073243.
Wang.
Lee.
Su.
Huang, and S.
Wang.
AuDelonix regia leaf extract (DRLE):
A potential therapeutic agent for cardioprotection,Ay PLoS One, vol.
11, no.
12, pp.
15Ae17, 2016, 1371/journal.
Shewale.
Deshmukh.
Patil, and V.
Patil.
AuAntiinflammatory activity of Delonix regia (Boj.
Ex.
Hoo.
,Ay Adv.
Pharmacol.
Sci.
, vol.
2012, 2012,
doi: 10.
1155/2012/789713.
Mathematics and Natural Sciences (FMIPA).
Brawijaya University, 2/UN01.
F09/PN/2024
REFERENCES