Natural Product-Based Discovery of Antibacterial Agents from Sophora tomentosa L. to Tackle Drug Resistance †
by
,
Supattra Poeaim
1,*
,
Patcharanun Laowklang
1,
Narumon Tangthirasunun
1 and
Thanarak Chantaraprasit
2 1
Department of Biology, School of Science, King Mongkut’s Institute of Technology Ladkrabang (KMITL), Bangkok 10520, Thailand
2
Department of Industrial Design, School of Architecture, Art, and Design, King Mongkut’s Institute of Technology Ladkrabang (KMITL), Bangkok 10520, Thailand
*
Author to whom correspondence should be addressed.
†
Presented at the 5th International Symposium on Frontiers in Molecular Science (ISFMS 2025), Kyoto, Japan, 26–29 August 2025.
Biol. Life Sci. Forum 2025, 53(1), 1; https://doi.org/10.3390/blsf2025053001
Published: 19 November 2025
(This article belongs to the Proceedings of The 5th International Symposium on Frontiers in Molecular Science)
Abstract
The rapid emergence of antimicrobial resistance (AMR) threatens global health by reducing the effectiveness of current antibiotics. Natural products remain an essential source of structurally diverse compounds with therapeutic potential. This study’s methanolic extracts of Sophora tomentosa L., a leguminous plant with traditional medicinal uses, were fractionated by liquid–liquid extraction and column chromatography. Dichloromethane and ethyl acetate fractions from leaves and seeds exhibited antibacterial activity against Kocuria rhizophila and Bacillus cereus. GC–MS profiling revealed alkaloids (e.g., matrine), flavonoids (e.g., catechin), phthalic acid derivatives, and fatty acids, supporting the potential of S. tomentosa as a source of novel antibacterial agents.
1. Introduction
Antimicrobial resistance (AMR) is a growing global health concern, underscoring the urgent need for new therapeutic agents. Natural products remain a valuable source of bioactive compounds, and several Sophora species have been reported to exhibit antimicrobial activity. For instance, silver nanoparticles synthesized from aqueous seed extracts of Sophora alopecuroides inhibited Staphylococcus aureus [1], while acetone extracts of S. pachycarpa roots showed inhibition of S. aureus [2]. Aqueous and methanolic leaf extracts of S. interrupta demonstrated strong effects against Escherichia coli, reaching inhibition zones of 29.50 ± 0.50 and 24.75 ± 0.43 mm, respectively [3]. Moreover, methanolic extracts of S. jaubertii seeds and stems suppressed several bacterial strains, with matrine identified as a primary active alkaloid [4].
These findings highlight the genus’s antimicrobial potential and indicate species and solvent-specific differences. Sophora tomentosa L., distributed along the coasts of Thailand, has been traditionally used to treat stomach pain, diarrhea, and abscesses, with the dosage determined by the patient’s age and number of seeds consumed. Although S. tomentosa holds notable ethnomedicinal value, scientific investigation of its bioactivities remains limited to a single study examining crude methanolic extracts of its leaves and seeds, which reported higher antioxidant and phenolic contents in the leaves and stronger antibacterial activity in the seeds, with both extracts containing alkaloids and coumarins [5]. In contrast to other Sophora species with documented antimicrobial properties, S. tomentosa remains critically underexplored, and no prior studies have linked its chemical composition to antibacterial activity. This reflects a clear knowledge gap, particularly regarding constituents identified through multisolvent fractionation and GC–MS analysis. Therefore, the present study aims to evaluate the antibacterial activities of S. tomentosa, with particular emphasis on its potential as a promising source of antibacterial agents.
2. Materials and Methods
2.1. Plant Material
Sophora tomentosa (the Thai name is Sara phat pit) leaves were collected from Koh Yao Yai, Phang Nga province and seeds were purchased from the herbal drug store in Nonthaburi province, Thailand. The species was taxonomically identified compared with reference specimens available at the Bangkok Herbarium, Department of Agriculture, Bangkok, Thailand.
2.2. Fractionation of Plant Extracts
Leaves and seeds were washed with tap water, shade-dried at 50 °C, and ground into coarse powder. Each part (leaf, L; seed, S) was macerated in methanol (30 g/300 mL) at room temperature for one week, and the filtrates were evaporated under reduced pressure to obtain methanol extracts. The crude extracts were then suspended in water and sequentially partitioned with hexane (H), dichloromethane (D), ethyl acetate (E), and n-butanol (B), leaving the residual aqueous layer (W), to yield LH–LW and SH–SW sub-extracts. Bioactivity screening indicated that the dichloromethane and ethyl acetate fractions exhibited the strongest activities; therefore, these were further subjected to column chromatography on silica gel. The mobile phase system was optimized based on Thin-layer chromatography (TLC) analysis, and eluates were monitored under UV light (254 and 366 nm) and visualized with anisaldehyde reagent. Fractions showing similar TLC profiles were pooled and designated as sub-fractions for subsequent bioactivity evaluation.
2.3. GC–MS Analysis of Bioactive Compounds
The chemical composition of the extracts was analyzed using gas chromatography-mass spectrometry (GC–MS). Extracts were dissolved in methanol and analyzed using an Agilent 6890 GC system coupled with an Agilent 5973 inert mass selective detector (MSD) at the Scientific Equipment Center, School of Science, King Mongkut’s Institute of Technology Ladkrabang.
2.4. Evaluation of Antibacterial Activity
2.4.1. Microorganisms and Culture Conditions
Antibacterial activity was assessed against eight different strains of bacteria, including six Gram-positive (Bacillus subtilis TISTR1248, B. cereus DMST5040, Kocuria rhizophila ATCC9341, Staphylococcus aureus TISTR746, S. epidermidis TISTR2141, and Propionibacterium acnes DMST14916) and two Gram-negative strains (Escherichia coli TISTR074 and Pseudomonas aeruginosa TISTR2370). All strains were cultured in Mueller-Hinton Broth (MHB) at 37 °C for 18–24 h under aerobic conditions, except P. acnes, which was grown anaerobically in Tryptic Soy Broth (TSB).
2.4.2. Disc Diffusion Assay
The antibacterial activity of the extracts was determined by the disc diffusion technique following the Clinical and Laboratory Standards Institute (CLSI) guidelines (2012) [6]. Test organisms were cultured in MHB and adjusted to the turbidity equivalent to a 0.5 McFarland standard. The suspensions were evenly spread on Mueller-Hinton Agar (MHA) plates using sterile swabs. Sterile paper discs (6 mm diameter) were impregnated with 1 mg of each extract dissolved in methanol or methanol–DMSO (10%, v/v), air-dried, and placed on the agar surface. Plates were incubated at 37 °C for 18–24 h under aerobic conditions, except P. acnes, which was incubated anaerobically. Gentamicin (10 µg/disc) was the positive control, while solvent-loaded discs were used as negative controls. The antibacterial effect was expressed as the diameter of inhibition zones (mm).
2.5. Statistical Analysis
All experiments were performed in triplicate, and results are presented as mean ± standard deviation (SD). Data were analyzed using one-way ANOVA (SPSS v26.0, IBM Corp., Armonk, NY, USA). Mean comparisons were conducted with Duncan’s multiple range test, and different letters indicate statistically significant differences at p < 0.05.
3. Results and Discussion
3.1. Subsection Sub-Fractionation by Column Chromatography
From the biological activity study of the solvent-partitioned extracts obtained by liquid–liquid extraction, the dichloromethane and ethyl acetate fractions of the leaf and seed extracts of S. tomentosa exhibited high bioactivity. Therefore, these fractions were subjected to further purification by column chromatography. The suitable solvent system for separating the components was determined to be hexane: ethyl acetate in a ratio of 3:7. TLC was used to monitor the separation process, in which the extracts were spotted onto TLC plates, sprayed with anisaldehyde reagent, and observed under UV light at 254 and 365 nm. The extracts could migrate from the baseline to the front line, producing distinct bands.
Fractionation of the leaf dichloromethane extract yielded 11 sub-fractions, designated as LDF (Leaf Dichloromethane Fraction 1–11). For example, the first sub-fraction obtained was named LDF1, followed by LDF2–LDF11. Sub-fractions with similar TLC profiles were combined. Likewise, the leaf ethyl acetate extract produced 8 sub-fractions (LEF1–8), the seed dichloromethane extract produced 8 sub-fractions (SDF1–8), and the seed ethyl acetate extract produced 8 sub-fractions (SEF1–8). The LDF and LEF sub-fractions appeared viscous, dark yellow to greenish-brown, and the SDF and SEF sub-fractions were oily, yellow to deep orange. In total, 35 sub-fractions were evaluated for antibacterial properties.
3.2. GC–MS Profiles of Bioactive Compounds
A total of 35 sub-fractions, including LDF1–11, LEF1–8, SDF1–8, and SEF1–8, were subjected to GC–MS analysis. For each sub-fraction, only the three most abundant compounds, presented with their relative percentages, are reported. Chemical profiling of the sub-fractions revealed distinct bioactive constituents across both leaf and seed extracts. In the dichloromethane leaf sub-fractions, phthalic acid and hexanedioic acid were predominant, while LDF10 and LDF11, which displayed potent antibacterial activity, were further characterized by matrine as a key compound (Table 1). The ethyl acetate leaf sub-fractions primarily contained hexadecanamide, 4H-pyran-4-one, and 2,3-dihydro-3,5-dihydroxy-6-methyl, compounds likely associated with both antioxidant and antibacterial effects. In the seed extracts, the dichloromethane sub-fractions were rich in 9-octadecenoic acid, 9,12-octadecadienoic acid, and hexadecanoic acid. In contrast, the ethyl acetate sub-fractions were characterized by n-hexadecanoic acid, 4H-pyran-4-one, and 2,3-dihydro-3,5-dihydroxy-6-methyl (DDMP), all of which are strongly linked to antioxidant and antibacterial activities (Table 2).
3.3. Antibacterial Activity
When considering both leaf and seed fractions, it was found that antibacterial activity against K. rhizophila and B. cereus was observed only in the dichloromethane and ethyl acetate layers. Therefore, only the sub-fractions from these solvent layers were selected and tested for further testing against the two bacterial strains. Paper disc diffusion assays were performed at 1 mg/disc concentrations, with gentamicin (10 µg/disc) as the positive control.
Among the leaf dichloromethane sub-fractions (LDF1–11), inhibition zones against K. rhizophila ranged from 0.00 to 10.10 ± 0.06 mm, and against B. cereus from 0.00 to 9.13 ± 0.02 mm. LDF11 exhibited the highest inhibitory activity against both bacterial strains. For the leaf ethyl acetate sub-fractions (LEF1–8), inhibition zones against K. rhizophila were in the range of 0.00–8.38 ± 0.03 mm, and against B. cereus in the range of 0.00–8.40 ± 0.04 mm, with LEF1 showing the most potent inhibition. The seed dichloromethane sub-fractions (SDF1–8) inhibited K. rhizophila with zones of 0.00–7.73 ± 0.11 mm and B. cereus with zones of 0.00–8.33 ± 0.02 mm, of which SDF8 displayed the most significant inhibition. The seed ethyl acetate sub-fractions (SEF1–8) produced inhibition zones ranging from 0.00 to 8.61 ± 0.04 mm for K. rhizophila and 0.00–9.01 ± 0.06 mm for B. cereus, with SEF8 being the most active. LDF11 showed the highest antibacterial activity against both K. rhizophila and B. cereus. No inhibition zones were observed for sub-fractions LDF4, LDF9, LEF4, LEF7, SDF1, SDF2, SDF5, SDF7, SEF1, SEF3, and SEF5. These results are illustrated in Figure 1 and summarized in Table 2.
Antimicrobial resistance poses a major global health challenge, projected to cause up to 10 million deaths annually by 2050 if left unaddressed. Several major interventions have been proposed to combat AMR, including improved infection prevention, rational antibiotic use, and development of new drugs and vaccines [7]. The present study contributes to this effort by highlighting natural products as a promising source for novel antibacterial agents. In this study, chemical profiling of S. tomentosa revealed bioactive compounds distributed across leaf and seed sub-fractions, many of which have previously been associated with antimicrobial properties. The dichloromethane leaf fractions were dominated by phthalic acid and hexanedioic acid, with matrine additionally detected in LDF10 and LDF11. Phthalic acid derivatives are known for their broad-spectrum antibacterial and antioxidant properties [8,9]. In contrast, hexanedioic acid and its derivatives have been linked to potent bioactivities in Thymus schimperi [10], whose study specifically aimed to identify medicinal plants effective against MDR-uropathogenic bacteria. The identification of matrine is particularly significant, as it has been established as a key antibacterial alkaloid in Sophora species [4], reinforcing the potential of S. tomentosa as a source of alkaloid-based antibacterial leads. In the ethyl acetate leaf fractions, the detection of hexadecanamide, 4H-pyran-4-one, and 2,3-dihydro-3,5-dihydroxy-6-methyl (DDMP) further supports their role in antibacterial and antioxidant activities. Hexadecanamide has been reported to inhibit E. coli and S. aureus while exhibiting radical scavenging capacity [11]. The dual activity of these compounds reflects a therapeutic advantage, as oxidative stress is often associated with bacterial pathogenesis and resistance mechanisms.
Seed fractions also yielded compounds of notable relevance to AMR. The dichloromethane seed fractions contained 9-octadecenoic acid, 9,12-octadecadienoic acid, and hexadecanoic acid, which have been consistently reported in natural extracts with antimicrobial and antioxidant activities [12,13]. These fatty acids may exert antibacterial effects by disrupting bacterial membranes, a mechanism distinct from conventional antibiotics, offering opportunities to counteract resistance. Similarly, the ethyl acetate seed fractions exhibited n-hexadecanoic acid, 4H-pyran-4-one, and DDMP, compounds previously linked to inhibition of multidrug-resistant bacteria such as S. aureus, B. subtilis, E. coli, and K. pneumoniae [14]. The distribution of fatty acids, heterocyclic compounds, and alkaloids across different fractions highlights the chemical diversity and multifunctional bioactivities of S. tomentosa. Identifying matrine alongside membrane-active fatty acids suggests a synergistic antibacterial potential that targets bacteria through multiple mechanisms. This is particularly valuable in AMR, where combination effects can reduce the likelihood of resistance development.
This study demonstrates preliminary in vitro antibacterial activity; however, the lack of in vivo validation limits conclusions regarding clinical relevance. Antibacterial screening was performed using disc diffusion assays following CLSI (2012) guidelines [6], which provide only an initial indication of activity. More quantitative approaches—such as microbroth dilution, time-kill kinetics, microscopy-based analyses, and molecular techniques (e.g., transcriptomics or proteomics)—will be required to elucidate the mechanism of action and confirm biological relevance. In addition, quantitative analyses of key polar phytochemicals, including total phenolics and flavonoids, were not conducted. Future work will therefore incorporate in vivo models, validated analytical methods (e.g., HPLC-DAD, UHPLC-QTOF), and detailed mechanistic studies following the isolation of the most active fractions and compounds.
The findings complement previous studies on other Sophora species [1,2,3], demonstrating antimicrobial efficacy against clinically relevant pathogens. Our results provide the first evidence that S. tomentosa, traditionally used in Thai ethnomedicine, harbors compounds with promising antibacterial potential. The alignment of our findings with prior reports across the genus underscores its significance as a natural reservoir for drug discovery.
4. Conclusions
The chemical and bioactivity profiles of S. tomentosa support its potential as a source of natural antibacterial agents. Combining alkaloids such as matrine with bioactive fatty acids and heterocyclic compounds, S. tomentosa may offer novel leads to tackle drug-resistant pathogens. Future studies on isolation, structural characterization, and mechanistic evaluation of these compounds are warranted to advance their potential application in the fight against AMR.
Author Contributions
Conceptualization, S.P., P.L., N.T. and T.C.; methodology, S.P. and P.L.; validation, S.P.; formal analysis, S.P. and P.L.; investigation, S.P.; resources, N.T. and T.C.; data curation, S.P.; writing—original draft preparation, S.P.; writing—review and editing, S.P., N.T. and T.C.; visualization, S.P. and P.L.; supervision, S.P.; project administration, S.P.; funding acquisition, S.P., N.T. and T.C. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by the National Research Council of Thailand (NRCT), grant number N21A661218.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Data are contained within the paper; further inquiries can be directed to the corresponding author.
Acknowledgments
The authors gratefully acknowledge financial support from the National Research Council of Thailand. This study was part of the Plant Genetic Conservation Project under the Royal Initiative of Her Royal Highness Princess Maha Chakri Sirindhorn (RSPG). The authors also thank the Koh Yao community, Phang Nga Province, for providing the leaf samples.
Conflicts of Interest
The authors declare no conflicts of interest.
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Figure 1.
Inhibition zones of K. rhizophila and B. cereus by leaf and seed sub-fractions (1 mg/disc): LDF, dichloromethane leaf; LEF, ethyl acetate leaf; SDF, dichloromethane seed; SEF, ethyl acetate seed; N, negative control; P, gentamicin (10 µg/disc) positive control.
Figure 1.
Inhibition zones of K. rhizophila and B. cereus by leaf and seed sub-fractions (1 mg/disc): LDF, dichloromethane leaf; LEF, ethyl acetate leaf; SDF, dichloromethane seed; SEF, ethyl acetate seed; N, negative control; P, gentamicin (10 µg/disc) positive control.
Table 1.
Major compounds identified by GC–MS in leaf and seed sub-fractions of S. tomentosa. Only the three most abundant compounds are reported for each sub-fraction.
Table 1.
Major compounds identified by GC–MS in leaf and seed sub-fractions of S. tomentosa. Only the three most abundant compounds are reported for each sub-fraction.
| Sub-Fractions | Compound 1 (Total %) | Compound 2 (Total %) | Compound 3 (Total %) |
|---|---|---|---|
| LDF1 | Phthalic acid, Din-butyl (33.95) | Phthalic acid, Di-2-ethylhexyl (25.35) | Phthalic acid, butyl octyl ester (15.13) |
| LDF2 | Gusperimus (53.90) | Vanillic acid (22.24) | Loliolide (10.65) |
| LDF3 | 3-Hydroxy-3′-methoxyflavone (32.90) | 9-Methoxy-6a,11a-dihydro-6H-benzofuro[3,2-c]chromen-3-ol (27.88) | Oleic Acid (21.98) |
| LDF4 | Hexanedioic acid, bis(2-ethylhexyl) ester (55.40) | Phthalic acid, dibutyl ester (14.33) | Phthalic acid, Di-2-ethylhexyl (14.00) |
| LDF5 | Hexanedioic acid, bis(2-ethylhexyl) ester (29.66) | 3-Hydroxy-4′-methoxyflavone (27.54) | Medicarpin (23.23) |
| LDF6 | 3-Formylindole (74.35) | Dehydrovomifoliol (7.30) | Hexanedioic acid, bis(2-ethylhexyl) ester (5.48) |
| LDF7 | Methyl 9-cis,11-trans-octadecadienoate (36.86) | Butylated Hydroxytoluene (27.98) | Hexadecanoic acid, methyl ester (14.56) |
| LDF8 | Benzoic acid, 4-methyl-2-trimethylsilyloxy-, TMS (69.62) | Linoelaidic acid (11.24) | Cholesta-5,7-dien-3-ol, 24-(2-methylpropylidene)-acetate (10.30) |
| LDF9 | Phthalic acid, diethyl ester (65.93) | Diphenyl sulfide (13.55) | 2,4-Di-tert-butylphenol (10.77) |
| LDF10 | 3′,8,8′-Trimethoxy-3-piperidyl-2,2′-binaphthalene-1,1′,4,4′-tetrone (63.51) | Matrine (13.92) | Heptacosane (7.09) |
| LDF11 | Phthalic acid, Di-2-ethylhexyl (32.48) | Matrine (24.18) | 4-Hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (22.19) |
| LEF1 | 2-Butenal 3 methyl (31.23) | Palmitoleamide (25.94) | Hexadecanamide (21.00) |
| LEF2 | 2-Butenal 3 methyl (48.87) | 3 beta-Chloro-5alpha-cholestan-6-one (30.95) | n-Hexadecanoic acid (10.15) |
| LEF3 | Nonacosane (27.49) | 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl (23.83) | Parametaxyleno (18.86) |
| LEF4 | Oleyl amide (43.43) | 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl (25.02) | 3beta-Chloro-5alpha-cholestan-6-one (14.16) |
| LEF5 | 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl (71.60) | Methyl 4-hydroxycinnamate (16.69) | 2-Propenoic acid, 3-(3-(isopropyloxycarbonyl)oxy-4-methoxyphenyl)-, methyl ester, (2E)- (11.71) |
| LEF6 | Benzaldehyde (60.44) | 9-Octadecenamide, (Z)- (18.25) | Sorbic alcohol (12.35) |
| LEF7 | Mesitylene (46.19) | Dinaphtho[2,1-d:1,2 f] [1,3,2] dioxaphosphepin-4-ol 4-oxide, O-TMS (24.79) | 9-Octadecenamide, (Z)- (19.31) |
| LEF8 | Mesitylene (83.45) | Phenylethyl alcohol (16.55) | - |
| SDF1 | Toluene (53.40) | 9-Octadecenoic acid, 12-hydroxy-, methyl ester, (Z)- (24.00) | Lagochilin (22.60) |
| SDF2 | Toluene (40.30) | Chloroxylenol (34.67) | Phenol, 2,4-di-tert-butyl- (25.03) |
| SDF3 | Hexadecanoic acid, methyl ester (42.67) | 9-Octadecenoic acid (Z)-, methyl ester (16.56) | Oleic Acid (13.12) |
| SDF4 | Hexadecanoic acid, methyl ester (67.29) | 9-Octadecenoic acid (Z)-, methyl ester (9.30) | Octadecanoic acid, methyl ester (8.88) |
| SDF5 | Hexadecanoic acid, methyl ester (48.15) | 9,12-Octadecadienoic acid (Z,Z)-, methyl ester (40.64) | Pantolactone (11.20) |
| SDF6 | 9-Octadecenoic acid, 12-hydroxy-, methyl ester, [R-(Z)]- (30.60) | Oxiraneoctanoic acid, 3-octyl-, methyl ester (21.64) | Pantolactone (17.00) |
| SDF7 | Ethylene Glycol (26.99) | 9-Octadecenoic acid,12-hydroxy, methyl ester, (z) (26.94) | Epoxyoleic acid (26.79) |
| SDF8 | 9,12-Octadecadienoic acid (Z,Z)- (34.57) | 9,12-Octadecadienoic acid (Z, Z)-, methyl ester (14.92) | L-Ascorbic acid (13.13) |
| SEF1 | Dimethyl Sulfoxide (97.56) | Sulphonylbismethan (2.12) | Toluene (0.32) |
| SEF2 | n-Hexadecanoic acid (39.29) | Ethylene Glycol (31.17) | Hexadecanoic acid, methyl ester (29.54) |
| SEF3 | Toluene (66.48) | n-Hexadecanoic acid (24.75) | Hexadecanoic acid, methyl ester (8.77) |
| SEF4 | 1-Dodecanol (49.97) | Dodecanoic acid, dodecyl ester (32.89) | n-Hexadecanoic acid (9.24) |
| SEF5 | 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl (92.37) | n-Hexadecanoic acid (7.63) | - |
| SEF6 | 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl (56.87) | Nonacosane (26.62) | Heptacosane (16.52) |
| SEF7 | Catechin (40.30) | Chloroxylenol (34.67) | Syrigol (25.03) |
| SEF8 | Phenylacetaldehyde (48.86) | n-Hexadecanoic acid (19.12) | Dinaphtho[2,1-d:1,2-f][1,3,2]dioxaphosphepin-4-ol 4-oxide, O-TMS (17.45) |
Note: LDF, dichloromethane leaf; LEF, ethyl acetate leaf; SDF, dichloromethane seed; SEF, ethyl acetate seed.
Table 2.
Inhibition zones (mm) of K. rhizophila and B. cereus by leaf and seed sub-fractions of S. tomentosa at 1 mg/disc.
Table 2.
Inhibition zones (mm) of K. rhizophila and B. cereus by leaf and seed sub-fractions of S. tomentosa at 1 mg/disc.
| Microorganisms | Kocuria rhizophila | Bacillus cereus | ||||||
|---|---|---|---|---|---|---|---|---|
| Sub-Fractions | LDF | LEF | SDF | SEF | LDF | LEF | SDF | SEF |
| 1 | 8.47 d ± 0.05 | 8.38 b ± 0.03 | 0 | 0 | 8.78 c ± 0.04 | 8.40 b ± 0.04 | 0 | 0 |
| 2 | 7.90 ef ± 0.04 | 7.68 e ± 0.06 | 0 | 8.11 d ± 0.00 | 7.49 d ± 0.06 | 8.15 bc ± 0.02 | 0 | 7.65 d ± 0.04 |
| 3 | 8.46 d ± 0.11 | 7.75 f ± 0.05 | 7.48 c ± 0.05 | 0 | 7.08 e ± 0.07 | 8.20 bc ± 0.06 | 7.15 c ± 0.04 | 0 |
| 4 | 0 | 0 | 7.11 d ± 0.04 | 8.20 c ± 0.03 | 0 | 0 | 6.36 e ± 0.05 | 7.72 e ± 0.02 |
| 5 | 7.79 f ± 0.06 | 7.97 d ± 0.04 | 0 | 0 | 6.92 f ± 0.01 | 8.06 d ± 0.05 | 0 | 0 |
| 6 | 8.08 e ± 0.01 | 8.12 c ± 0.03 | 7.01 e ± 0.01 | 8.00 e ± 0.02 | 7.27 de ± 0.04 | 7.95 e ± 0.02 | 6.76 d ± 0.05 | 8.87 c ± 0.02 |
| 7 | 8.67 d ± 0.11 | 0 | 0 | 8.25 c ± 0.06 | 7.29 de ± 0.00 | 0 | 0 | 8.96 c ± 0.02 |
| 8 | 9.06 c ± 0.07 | 7.98 e ± 0.05 | 7.73 b ± 0.11 | 8.61 b ± 0.04 | 7.43 d ± 0.02 | 8.17 bc ± 0.06 | 8.33 b ± 0.02 | 9.01 b ± 0.06 |
| 9 | 0 | - | - | - | 0 | - | - | - |
| 10 | 9.36 bc ± 0.12 | - | - | - | 8.94 c ± 0.02 | - | - | - |
| 11 | 10.10 b ± 0.06 | - | - | - | 9.13 b ± 0.02 | - | - | - |
| Gentamicin | 27.56 a ± 0.70 | 25.24 a ± 0.83 | ||||||
Note: LDF, dichloromethane leaf; LEF, ethyl acetate leaf; SDF, dichloromethane seed; SEF, ethyl acetate seed; The data are expressed as mean ± SD. Different superscript letters (a–f) indicate statistically significant differences according to Duncan’s multiple range test (p < 0.05).
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Poeaim, S.; Laowklang, P.; Tangthirasunun, N.; Chantaraprasit, T. Natural Product-Based Discovery of Antibacterial Agents from Sophora tomentosa L. to Tackle Drug Resistance. Biol. Life Sci. Forum 2025, 53, 1. https://doi.org/10.3390/blsf2025053001
AMA Style
Poeaim S, Laowklang P, Tangthirasunun N, Chantaraprasit T. Natural Product-Based Discovery of Antibacterial Agents from Sophora tomentosa L. to Tackle Drug Resistance. Biology and Life Sciences Forum. 2025; 53(1):1. https://doi.org/10.3390/blsf2025053001
Chicago/Turabian StylePoeaim, Supattra, Patcharanun Laowklang, Narumon Tangthirasunun, and Thanarak Chantaraprasit. 2025. "Natural Product-Based Discovery of Antibacterial Agents from Sophora tomentosa L. to Tackle Drug Resistance" Biology and Life Sciences Forum 53, no. 1: 1. https://doi.org/10.3390/blsf2025053001
APA StylePoeaim, S., Laowklang, P., Tangthirasunun, N., & Chantaraprasit, T. (2025). Natural Product-Based Discovery of Antibacterial Agents from Sophora tomentosa L. to Tackle Drug Resistance. Biology and Life Sciences Forum, 53(1), 1. https://doi.org/10.3390/blsf2025053001
