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Abdulahi S K. Comparison of antityphoidal efficacy of Moringa oleifera seed oil to antibiotics against Salmonella typhi. mljgoums 2026; 20 (1) :7-10
URL: http://mlj.goums.ac.ir/article-1-1860-en.html
URL: http://mlj.goums.ac.ir/article-1-1860-en.html
The Federal University of Technology Akure, P.M.B. 704, Akure, Ondo State, Nigeria , kayode.abdulahi2@gmail.com
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Discussion
The evaluation of the anti-typhoidal activity of M. oleifera seed oil on typed and clinical S. typhi strains indicates limited or negligible inhibitory effects at dosages of 1000 and 500 mg. Several factors contribute to this observation, including the presence of lipopolysaccharide (LPS) in S. typhi (11), inadequate or absent specific phytochemicals (6,12), and the choice of solvent used for seed oil extraction (6) from M. oleifera. LPS shields the bacteria from bactericidal agents by preventing the entry of hydrophobic molecules, while the constant alteration of the bacteria's outer membrane structure aids in their defense against such agents (11). These findings align with studies reporting weak or no inhibitory effects of M. oleifera seed oil on tested Gram-negative bacterial strains, possibly due to the strains' resistance to the constituents of M. oleifera (12).
Phenolic compounds are identified as the primary contributors to the antimicrobial efficacy (12,13) of essential oils against Gram-negative bacteria, which are lacking in this study. The current research addresses the limitations of previous studies (12), such as the unknown extraction source and undetermined phytochemical constituents of the M. oleifera seed oil used. Furthermore, although flavonoids exhibit antimicrobial properties (13), their abundance in this study is minimal. Additionally, other studies demonstrate the antibacterial potential of bioactive compounds such as phenols, alkaloids, and flavonoids present in M. oleifera seed extract obtained using methanol as a solvent, suggesting their potential as antibiotic ingredients against Gram-positive and Gram-negative bacterial infections (6,12).
Comparison with previous studies
The findings of this study, which indicate the ineffectiveness of M. oleifera seed oil against S. typhi, are consistent with some previous research. For instance, Abu El-Wafa and Abd El-All (12) reported weak or no inhibitory effects of M. oleifera seed oil on certain Gram-negative bacteria. This similarity could be attributed to factors such as the presence of LPS in Gram-negative bacteria, which hinders the penetration of hydrophobic compounds, and the absence of key antimicrobial phytochemicals such as phenols in the oil extract, as observed in our study.
However, our results contrast with studies that have demonstrated the antibacterial potential of M. oleifera seed extracts. Akintelu et al. (6) found that methanol extracts of M. oleifera seeds exhibited antibacterial activity, likely due to the presence of compounds such as phenols and alkaloids. This discrepancy highlights the importance of the extraction solvent, as different solvents can extract different phytochemicals, thereby influencing the bioactivity of the extract.
Implications for treatment
The results of this study have significant implications for the potential use of M. oleifera seed oil in treating typhoid fever. The observed lack of significant anti-typhoidal activity suggests that this particular preparation of M. oleifera seed oil is not a suitable alternative to conventional antibiotic treatments. It reinforces the importance of relying on established antibiotic therapies for the management of typhoid fever.
Conclusion
In conclusion, while M. oleifera seed oil may possess the capability to treat other diseases, it proves ineffective against typhoid fever. The concentration of phytochemical constituents in the seed oil of M. oleifera is insufficient to cause death or meaningful inhibition of S. typhi growth.
Limitations and future research
This study has some limitations that should be considered. First, the study focused solely on the in vitro activity of M. oleifera seed oil. Further research is needed to evaluate its efficacy in in vivo models, which can better mimic the complex interactions within a living organism. Second, while the phytochemical composition of the seed oil was analyzed, a more detailed investigation into the specific compounds responsible (Or the lack thereof) for the observed antibacterial activity could provide deeper insights.
Future research directions could include:
Acknowledgement
The author sincerely acknowledges Professor Dada and Mr. Femi for their valuable guidance and assistance in conducting the experiments.
Funding sources
Not applicable
Ethical statement
This study utilized clinical S. typhi isolates obtained from the Microbiology Laboratory, University of Ibadan Teaching Hospital, Ibadan, Nigeria. The use of these isolates was approved by the Ethical Review Committee of the University of Ibadan Teaching Hospital (UI/EC/22/0143). As this research involved the use of existing clinical isolates and did not involve direct interaction with patients, individual patient consent was not required. This study was conducted in accordance with all relevant guidelines and regulations.
Conflicts of interest
The author declares no conflicts of interest. The author is solely responsible for the content and writing of this article.
Author contributions
Abdulahi S.K. designed the study, conducted the experiments, analyzed and interpreted the data, wrote the manuscript, revised it critically, and approved the final version.
Data availability statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Full-Text: (229 Views)
Introduction
Throughout history, typhoid fever has presented a significant challenge to human populations and remains an ongoing public health concern, causing approximately 200,000 deaths annually (1). This disease is endemic in are:as char:acterized by inadequate sanitation standards (2). Outbreaks often occur due to the contamination of water supplies through various means, such as the cross-connection of human and polluted water sources, faecal contamination of wells, or the consumption of contaminated poultry products. Salmonella typhi has been identified as the primary causative agent of typhoid fever (1). This Gram-negative, flagellated, non-encapsulated, facultative anaerobic bacillus differentiates itself from other Salmonella infections by manifesting as a life-threatening systemic disease rather than the self-limiting gastroenteritis commonly associated with most other Salmonella strains. Moreover, S. typhi exclusively infects humans, unlike other Salmonella strains that can infect a wide range of hosts (1,2). The clinical presentation of typhoid fever resulting from S. typhi infection includes symptoms such as malaise, diffuse abdominal pain, and constipation (3). Untreated typhoid fever is a debilitating illness that can progress to delirium, obtundation, intestinal haemorrhage, bowel perforation, and ultimately death within one month of symptom onset (3). Over 90% of typhoid patients can be effectively managed with oral antibiotics, along with reliable care and close medical monitoring to identify and address complications or inadequate responses to treatment (4). However, the issue of relapse after antibiotic treatment and the growing resistance of S. typhi to conventional drugs have led to investigations into the potential use of medicinal plants as alternative therapeutic options (5).
The use of herbal medicine, including Moringa oleifera, has been documented in Nigeria and other countries due to its cultural acceptance, affordability, accessibility, and the presence of bioactive compounds capable of combating diseases caused by microorganisms, viruses, insects, and parasites (5). The secondary metabolites present in the seed extract of M. oleifera, such as alkaloids, tannins, saponins, phenols, and flavonoids, contribute to the extract's antibacterial activity (6). Consequently, the aim of this study is to evaluate the in-vitro anti-typhoidal activity of M. oleifera seed oil.
Methods
Seed collection
The seeds of M. oleifera were obtained from a farmland in Bolorunduro (Coordinates 7.4209°N, 5.00114°E), Ifedore LGA, Ondo State. The seeds were then authenticated at the Department of Crop, Soil, and Pest (CSP) Management, School of Agricultural Technology, The Federal University of Technology, Akure, Ondo State, Nigeria.
Preparation of plant extract
Dehulled and cleaned seeds were sun-dried until they reached a constant weight of 2 kg. The dried seeds were then crushed and finely pulverized using a Philip blender (Model HR2102). The oil from M. oleifera seeds was extracted using 240 mL of n-hexane in a Soxhlet extractor arrangement. The n-hexane was evaporated from the obtained oil using a rotary evaporator, and the remaining oil was quantified and stored in a glass bottle for later use (7).
Seed oil dosage preparation
The seed oil of M. oleifera was reconstituted with Tween 20 and sterile distilled water to prepare various concentrations: 1000, 500, 250, 125, and 62.5 mg/mL (7) for the anti-typhoidal assay. The dosages of the seed oil administered to the typed and clinical S. typhi strains were prepared by dissolving 1.0 g of the seed oil in a sterile universal bottle containing 8 mL of distilled water and 2 mL of Tween 20 to obtain a 1000 mg/mL dosage. The dosages of 500, 250, 125, and 62.5 mg/mL were obtained through successive two-fold dilutions from the 1000 mg/mL concentration.
Source and preservation of bacteria
Clinical and typed S. typhi strains were obtained from the Microbiology Laboratory, University of Ibadan Teaching Hospital, Ibadan, Nigeria, and transferred to the Department of Microbiology, Federal University of Akure (FUTA). The standard S. typhi used in this study was S. typhi ATCC 6539. This standard strain is a Gram-negative, flagellated, non-encapsulated, facultative anaerobic bacillus. Standard inocula of both clinical and typed S. typhi strains were used in the study, and the bacterial cell density was quantified using the method described by Cheesbrough (8).
Preparation of standard inocula of Salmonella typhi
The method employed for preparing the standard inocula of S. typhi for in vitro assay was based on the procedure described by Akinyemi and Dada (3). Overnight cultures of the isolates were transferred to tubes containing sterile saline. The bacterial suspension was compared to 0.5 McFarland standards using black lines drawn on a white sheet of paper. The density of the bacterial suspension was adjusted to match the McFarland 0.5 standard by adding sterile saline or additional bacterial growth. The bacterial suspension was then diluted to obtain a concentration of 106 colony-forming units per millilitre (CFU/mL).
Antityphoidal sensitivity testing of the extract on clinical and typed isolates
The procedure described by Muhammed et al. (8) was adopted for this step. Using a sterile pipette, 0.5 mL of the bacterial suspension was drawn and aseptically introduced into sterile Petri dishes. Mueller-Hinton Agar (MHA), cooled to approximately 45°C, was poured into the Petri dishes containing the S. typhi suspension. Each Petri dish was swirled gently in a clockwise direction to ensure the homogeneous distribution of bacteria within the MHA. After allowing the plates to stand for 40 minutes, four wells of approximately 6 mm were aseptically bored into each agar plate using a sterile cork borer, with a distance of 30 mm between adjacent wells and between the wells and the edge of the Petri dish. A 0.1 mL volume of the different concentrations of the extract was then introduced into each well using a sterile syringe. A control well at the centre contained 0.1 mL of the extracting solvent (n-hexane, Sigma-Aldrich). The plates were labelled and incubated at 37°C for 24, 48, and 72 hours. The resulting zones of inhibition were measured using a calliper, and the average of three readings was taken as the zone of inhibition for the bacterial isolate at that specific concentration and contact time.
Antibiotics assay
The effectiveness of standard antibiotics from Oxoid, such as gentamicin (30 μg), chloramphenicol (30 μg), ciprofloxacin (10 μg), tetracycline (30 μg), amoxicillin (30 μg), and nalidixic acid (30 μg), was compared with the seed oil of M. oleifera against clinical and typed S. typhi isolates. Using a sterile pipette, 0.1 mL of the bacterial suspension was drawn and aseptically introduced into sterile Petri dishes. Mueller–Hinton Agar (MHA), cooled to about 45°C, was poured into the Petri dishes containing the S. typhi suspension. Each Petri dish was gently swirled in a clockwise direction to ensure even distribution of the bacteria. The plates were allowed to stand for 40 minutes to enable the bacteria to establish in the medium. The standard discs were placed aseptically on the plates using sterile forceps. The plates were incubated at 37°C for 24 hours, after which the zones of inhibition around the discs were observed. The diameters of the clear zones were measured in millimetres (mm) using a calliper, and the average of three readings was taken as the zone of inhibition for the bacterial isolate at that specific concentration and contact time (2).
Determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC)
The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extracts were determined using the broth dilution technique. Dilutions of the extract in Mueller-Hinton broth were prepared in tubes. The tubes containing the different concentrations of seed oil in Mueller-Hinton broth were then inoculated with 0.5 mL of the standardized culture. The cultures were incubated at 37°C for 48 hours, and the lowest concentration that inhibited growth was considered the MIC. Visual observation was performed to detect turbidity in the test tubes (3).
Phytochemical screening of seed oil of Moringa oleifera
The seed oil of M. oleifera was subjected to quantitative and qualitative phytochemical screening using standard procedures described by Ijarotimi et al. (9) and Donkor et al. (10).
Ethical considerations
This study used clinical isolates obtained from the Microbiology Laboratory, University of Ibadan Teaching Hospital, Ibadan, Nigeria. The use of these isolates was approved by the Ethical Review Committee of the University of Ibadan Teaching Hospital (Approval number: UI/EC/22/0143).
Results
Antityphoidal activity of seed oil of Moringa oleifera and antibiotics assay
The evaluation of the antityphoidal activity of the seed oil of M. oleifera against typed and clinical isolates of S. typhi is presented in Table 1. The results indicate that S. typhi exhibited weak or no susceptibility to the seed oil of M. oleifera. The zones of inhibition observed for typed and clinical S. typhi at a concentration of 1000 mg/mL of M. oleifera seed oil were 0.21 ± 0.04 mm and 0.23 ± 0.03 mm, respectively. At a concentration of 500 mg/mL, the zones of inhibition were 0.20 ± 0.03 mm and 0.19 ± 0.01 mm for typed and clinical S. typhi, respectively. The MIC for both typed and clinical S. typhi were found to be 500 mg/mL, while the MBC could not be determined, as there was no evidence of bacterial death at a concentration of 1000 mg/mL
Throughout history, typhoid fever has presented a significant challenge to human populations and remains an ongoing public health concern, causing approximately 200,000 deaths annually (1). This disease is endemic in are:as char:acterized by inadequate sanitation standards (2). Outbreaks often occur due to the contamination of water supplies through various means, such as the cross-connection of human and polluted water sources, faecal contamination of wells, or the consumption of contaminated poultry products. Salmonella typhi has been identified as the primary causative agent of typhoid fever (1). This Gram-negative, flagellated, non-encapsulated, facultative anaerobic bacillus differentiates itself from other Salmonella infections by manifesting as a life-threatening systemic disease rather than the self-limiting gastroenteritis commonly associated with most other Salmonella strains. Moreover, S. typhi exclusively infects humans, unlike other Salmonella strains that can infect a wide range of hosts (1,2). The clinical presentation of typhoid fever resulting from S. typhi infection includes symptoms such as malaise, diffuse abdominal pain, and constipation (3). Untreated typhoid fever is a debilitating illness that can progress to delirium, obtundation, intestinal haemorrhage, bowel perforation, and ultimately death within one month of symptom onset (3). Over 90% of typhoid patients can be effectively managed with oral antibiotics, along with reliable care and close medical monitoring to identify and address complications or inadequate responses to treatment (4). However, the issue of relapse after antibiotic treatment and the growing resistance of S. typhi to conventional drugs have led to investigations into the potential use of medicinal plants as alternative therapeutic options (5).
The use of herbal medicine, including Moringa oleifera, has been documented in Nigeria and other countries due to its cultural acceptance, affordability, accessibility, and the presence of bioactive compounds capable of combating diseases caused by microorganisms, viruses, insects, and parasites (5). The secondary metabolites present in the seed extract of M. oleifera, such as alkaloids, tannins, saponins, phenols, and flavonoids, contribute to the extract's antibacterial activity (6). Consequently, the aim of this study is to evaluate the in-vitro anti-typhoidal activity of M. oleifera seed oil.
Methods
Seed collection
The seeds of M. oleifera were obtained from a farmland in Bolorunduro (Coordinates 7.4209°N, 5.00114°E), Ifedore LGA, Ondo State. The seeds were then authenticated at the Department of Crop, Soil, and Pest (CSP) Management, School of Agricultural Technology, The Federal University of Technology, Akure, Ondo State, Nigeria.
Preparation of plant extract
Dehulled and cleaned seeds were sun-dried until they reached a constant weight of 2 kg. The dried seeds were then crushed and finely pulverized using a Philip blender (Model HR2102). The oil from M. oleifera seeds was extracted using 240 mL of n-hexane in a Soxhlet extractor arrangement. The n-hexane was evaporated from the obtained oil using a rotary evaporator, and the remaining oil was quantified and stored in a glass bottle for later use (7).
Seed oil dosage preparation
The seed oil of M. oleifera was reconstituted with Tween 20 and sterile distilled water to prepare various concentrations: 1000, 500, 250, 125, and 62.5 mg/mL (7) for the anti-typhoidal assay. The dosages of the seed oil administered to the typed and clinical S. typhi strains were prepared by dissolving 1.0 g of the seed oil in a sterile universal bottle containing 8 mL of distilled water and 2 mL of Tween 20 to obtain a 1000 mg/mL dosage. The dosages of 500, 250, 125, and 62.5 mg/mL were obtained through successive two-fold dilutions from the 1000 mg/mL concentration.
Source and preservation of bacteria
Clinical and typed S. typhi strains were obtained from the Microbiology Laboratory, University of Ibadan Teaching Hospital, Ibadan, Nigeria, and transferred to the Department of Microbiology, Federal University of Akure (FUTA). The standard S. typhi used in this study was S. typhi ATCC 6539. This standard strain is a Gram-negative, flagellated, non-encapsulated, facultative anaerobic bacillus. Standard inocula of both clinical and typed S. typhi strains were used in the study, and the bacterial cell density was quantified using the method described by Cheesbrough (8).
Preparation of standard inocula of Salmonella typhi
The method employed for preparing the standard inocula of S. typhi for in vitro assay was based on the procedure described by Akinyemi and Dada (3). Overnight cultures of the isolates were transferred to tubes containing sterile saline. The bacterial suspension was compared to 0.5 McFarland standards using black lines drawn on a white sheet of paper. The density of the bacterial suspension was adjusted to match the McFarland 0.5 standard by adding sterile saline or additional bacterial growth. The bacterial suspension was then diluted to obtain a concentration of 106 colony-forming units per millilitre (CFU/mL).
Antityphoidal sensitivity testing of the extract on clinical and typed isolates
The procedure described by Muhammed et al. (8) was adopted for this step. Using a sterile pipette, 0.5 mL of the bacterial suspension was drawn and aseptically introduced into sterile Petri dishes. Mueller-Hinton Agar (MHA), cooled to approximately 45°C, was poured into the Petri dishes containing the S. typhi suspension. Each Petri dish was swirled gently in a clockwise direction to ensure the homogeneous distribution of bacteria within the MHA. After allowing the plates to stand for 40 minutes, four wells of approximately 6 mm were aseptically bored into each agar plate using a sterile cork borer, with a distance of 30 mm between adjacent wells and between the wells and the edge of the Petri dish. A 0.1 mL volume of the different concentrations of the extract was then introduced into each well using a sterile syringe. A control well at the centre contained 0.1 mL of the extracting solvent (n-hexane, Sigma-Aldrich). The plates were labelled and incubated at 37°C for 24, 48, and 72 hours. The resulting zones of inhibition were measured using a calliper, and the average of three readings was taken as the zone of inhibition for the bacterial isolate at that specific concentration and contact time.
Antibiotics assay
The effectiveness of standard antibiotics from Oxoid, such as gentamicin (30 μg), chloramphenicol (30 μg), ciprofloxacin (10 μg), tetracycline (30 μg), amoxicillin (30 μg), and nalidixic acid (30 μg), was compared with the seed oil of M. oleifera against clinical and typed S. typhi isolates. Using a sterile pipette, 0.1 mL of the bacterial suspension was drawn and aseptically introduced into sterile Petri dishes. Mueller–Hinton Agar (MHA), cooled to about 45°C, was poured into the Petri dishes containing the S. typhi suspension. Each Petri dish was gently swirled in a clockwise direction to ensure even distribution of the bacteria. The plates were allowed to stand for 40 minutes to enable the bacteria to establish in the medium. The standard discs were placed aseptically on the plates using sterile forceps. The plates were incubated at 37°C for 24 hours, after which the zones of inhibition around the discs were observed. The diameters of the clear zones were measured in millimetres (mm) using a calliper, and the average of three readings was taken as the zone of inhibition for the bacterial isolate at that specific concentration and contact time (2).
Determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC)
The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extracts were determined using the broth dilution technique. Dilutions of the extract in Mueller-Hinton broth were prepared in tubes. The tubes containing the different concentrations of seed oil in Mueller-Hinton broth were then inoculated with 0.5 mL of the standardized culture. The cultures were incubated at 37°C for 48 hours, and the lowest concentration that inhibited growth was considered the MIC. Visual observation was performed to detect turbidity in the test tubes (3).
Phytochemical screening of seed oil of Moringa oleifera
The seed oil of M. oleifera was subjected to quantitative and qualitative phytochemical screening using standard procedures described by Ijarotimi et al. (9) and Donkor et al. (10).
Ethical considerations
This study used clinical isolates obtained from the Microbiology Laboratory, University of Ibadan Teaching Hospital, Ibadan, Nigeria. The use of these isolates was approved by the Ethical Review Committee of the University of Ibadan Teaching Hospital (Approval number: UI/EC/22/0143).
Results
Antityphoidal activity of seed oil of Moringa oleifera and antibiotics assay
The evaluation of the antityphoidal activity of the seed oil of M. oleifera against typed and clinical isolates of S. typhi is presented in Table 1. The results indicate that S. typhi exhibited weak or no susceptibility to the seed oil of M. oleifera. The zones of inhibition observed for typed and clinical S. typhi at a concentration of 1000 mg/mL of M. oleifera seed oil were 0.21 ± 0.04 mm and 0.23 ± 0.03 mm, respectively. At a concentration of 500 mg/mL, the zones of inhibition were 0.20 ± 0.03 mm and 0.19 ± 0.01 mm for typed and clinical S. typhi, respectively. The MIC for both typed and clinical S. typhi were found to be 500 mg/mL, while the MBC could not be determined, as there was no evidence of bacterial death at a concentration of 1000 mg/mL
|
Table 1. Antityphoidal activity of seed oil of Moringa oleifera against typed and clinical Salmonella typhi
.PNG) Values are mean ± S.E (n = 3). Means with different superscripts in the same row show significant (P ≤ 0.05). |
.PNG) Figure 1. Comparative zones of inhibition of standard antibiotics and seed oil of Moringa oleifera against clinical and typed Salmonella typhi (Abbreviations: Hex, n-hexane; M.O, seed oil of M. oleifera; CRO, Ceftriaxone; GN, Gentamicin; AK, Amikacin; CIP, Ciprofloxacin; C, Chloramphenicol; AML, Amoxicillin; CAZ, Ceftazidime; TE, Tetracycline). |
Phytochemical constituents of seed oil of Moringa oleifera
Table 2 presents the phytochemical constituents of the seed oil of M. oleifera. The analysis reveals the presence of various qualitative and quantitative phytochemical bioactives in the seed oil of M. oleifera. The secondary metabolites identified include terpenoid, cardiac glycosides, saponin, tannin, and flavonoid, with respective amounts of 5.52 ± 0.04 mg/100 g, 3.84 ± 0.05 mg/100 g, 1.55 ± 0.27 mg/100 g, 1.01 ± 0.01 mg/100 g, and 0.45 ± 0.01 mg/100 g. However, phytochemicals such as steroid, phlobatannin, alkaloid, and anthraquinone were found to be absent in the seed oil of M. oleifera. The phytochemical composition in this study is consistent with the findings of Makanjuola et al. (14). However, this contrasts with the study by Akintelu et al. (6), which reports the presence of phenols, alkaloids, and other similar components in the seed extract of M. oleifera using methanol as a solvent. The diverse phytochemical constituents in M. oleifera contribute to its pharmacological uses, medicinal potency, and disease protection (7,13,15).
Table 2 presents the phytochemical constituents of the seed oil of M. oleifera. The analysis reveals the presence of various qualitative and quantitative phytochemical bioactives in the seed oil of M. oleifera. The secondary metabolites identified include terpenoid, cardiac glycosides, saponin, tannin, and flavonoid, with respective amounts of 5.52 ± 0.04 mg/100 g, 3.84 ± 0.05 mg/100 g, 1.55 ± 0.27 mg/100 g, 1.01 ± 0.01 mg/100 g, and 0.45 ± 0.01 mg/100 g. However, phytochemicals such as steroid, phlobatannin, alkaloid, and anthraquinone were found to be absent in the seed oil of M. oleifera. The phytochemical composition in this study is consistent with the findings of Makanjuola et al. (14). However, this contrasts with the study by Akintelu et al. (6), which reports the presence of phenols, alkaloids, and other similar components in the seed extract of M. oleifera using methanol as a solvent. The diverse phytochemical constituents in M. oleifera contribute to its pharmacological uses, medicinal potency, and disease protection (7,13,15).
|
Table 2. Phytochemical constituents of seed oil of Moringa oleifera
.PNG) Values are mean ± S.E (n = 3). Means with different superscripts in the same column show significant (P ≤ 0.05). KEYS: + = Present; - = Absent |
Discussion
The evaluation of the anti-typhoidal activity of M. oleifera seed oil on typed and clinical S. typhi strains indicates limited or negligible inhibitory effects at dosages of 1000 and 500 mg. Several factors contribute to this observation, including the presence of lipopolysaccharide (LPS) in S. typhi (11), inadequate or absent specific phytochemicals (6,12), and the choice of solvent used for seed oil extraction (6) from M. oleifera. LPS shields the bacteria from bactericidal agents by preventing the entry of hydrophobic molecules, while the constant alteration of the bacteria's outer membrane structure aids in their defense against such agents (11). These findings align with studies reporting weak or no inhibitory effects of M. oleifera seed oil on tested Gram-negative bacterial strains, possibly due to the strains' resistance to the constituents of M. oleifera (12).
Phenolic compounds are identified as the primary contributors to the antimicrobial efficacy (12,13) of essential oils against Gram-negative bacteria, which are lacking in this study. The current research addresses the limitations of previous studies (12), such as the unknown extraction source and undetermined phytochemical constituents of the M. oleifera seed oil used. Furthermore, although flavonoids exhibit antimicrobial properties (13), their abundance in this study is minimal. Additionally, other studies demonstrate the antibacterial potential of bioactive compounds such as phenols, alkaloids, and flavonoids present in M. oleifera seed extract obtained using methanol as a solvent, suggesting their potential as antibiotic ingredients against Gram-positive and Gram-negative bacterial infections (6,12).
Comparison with previous studies
The findings of this study, which indicate the ineffectiveness of M. oleifera seed oil against S. typhi, are consistent with some previous research. For instance, Abu El-Wafa and Abd El-All (12) reported weak or no inhibitory effects of M. oleifera seed oil on certain Gram-negative bacteria. This similarity could be attributed to factors such as the presence of LPS in Gram-negative bacteria, which hinders the penetration of hydrophobic compounds, and the absence of key antimicrobial phytochemicals such as phenols in the oil extract, as observed in our study.
However, our results contrast with studies that have demonstrated the antibacterial potential of M. oleifera seed extracts. Akintelu et al. (6) found that methanol extracts of M. oleifera seeds exhibited antibacterial activity, likely due to the presence of compounds such as phenols and alkaloids. This discrepancy highlights the importance of the extraction solvent, as different solvents can extract different phytochemicals, thereby influencing the bioactivity of the extract.
Implications for treatment
The results of this study have significant implications for the potential use of M. oleifera seed oil in treating typhoid fever. The observed lack of significant anti-typhoidal activity suggests that this particular preparation of M. oleifera seed oil is not a suitable alternative to conventional antibiotic treatments. It reinforces the importance of relying on established antibiotic therapies for the management of typhoid fever.
Conclusion
In conclusion, while M. oleifera seed oil may possess the capability to treat other diseases, it proves ineffective against typhoid fever. The concentration of phytochemical constituents in the seed oil of M. oleifera is insufficient to cause death or meaningful inhibition of S. typhi growth.
Limitations and future research
This study has some limitations that should be considered. First, the study focused solely on the in vitro activity of M. oleifera seed oil. Further research is needed to evaluate its efficacy in in vivo models, which can better mimic the complex interactions within a living organism. Second, while the phytochemical composition of the seed oil was analyzed, a more detailed investigation into the specific compounds responsible (Or the lack thereof) for the observed antibacterial activity could provide deeper insights.
Future research directions could include:
- Evaluating the synergistic effects of combining M. oleifera seed oil with antibiotics.
- Investigating the potential of other extraction methods to obtain M. oleifera seed oil with enhanced anti-typhoidal activity.
- Identifying the specific compounds in M. oleifera seed oil that may have weak antibacterial effects and exploring ways to enhance their activity.
Acknowledgement
The author sincerely acknowledges Professor Dada and Mr. Femi for their valuable guidance and assistance in conducting the experiments.
Funding sources
Not applicable
Ethical statement
This study utilized clinical S. typhi isolates obtained from the Microbiology Laboratory, University of Ibadan Teaching Hospital, Ibadan, Nigeria. The use of these isolates was approved by the Ethical Review Committee of the University of Ibadan Teaching Hospital (UI/EC/22/0143). As this research involved the use of existing clinical isolates and did not involve direct interaction with patients, individual patient consent was not required. This study was conducted in accordance with all relevant guidelines and regulations.
Conflicts of interest
The author declares no conflicts of interest. The author is solely responsible for the content and writing of this article.
Author contributions
Abdulahi S.K. designed the study, conducted the experiments, analyzed and interpreted the data, wrote the manuscript, revised it critically, and approved the final version.
Data availability statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Research Article: Research Article |
Subject:
bacteriology
Received: 2024/08/27 | Accepted: 2025/07/26 | Published: 2026/06/3 | ePublished: 2026/06/3
Received: 2024/08/27 | Accepted: 2025/07/26 | Published: 2026/06/3 | ePublished: 2026/06/3
References
1. Galán JE. Typhoid toxin provides a window into typhoid fever and the biology of Salmonella typhi. Proc Natl Acad Sci U S A. 2016;113(23):6338-44. [View at Publisher] [DOI] [PMID] [Google Scholar]
2. Dada EO, Faleye OS. In-vitro and In-vivo Activities of the Ethanol Pulp Extract of Annona muricata (Linn) Fruit in Albino Rats Infected with Salmonella typhi. J Adv Med Pharm Sci. 2016;5(4):1-12. [View at Publisher] [DOI] [PMID] [Google Scholar]
3. Akinyemi OI, Dada EO. Phytochemical Screening and Antityphoid Properties of Ethanolic Leaf Extracts of Parquetina nigrescens. J Agric Biol Sci. 2013;8(11):1-8. [View at Publisher] [Google Scholar]
4. National Institute for Communicable Diseases (NICD). Typhoid: NICD recommendations for diagnosis, management and public health response. Outbreak response, division of public health surveillance and response centre for enteric diseases. Guidelines_typhoid. 2016;125:1-20. [View at Publisher]
5. Ekeopara CA, Ugoha AM. The Contributions of African Traditional Medicine to Nigeria's Health Care Delivery System. J Humanit Soc Sci. 2017;22(5):32-43. [View at Publisher] [DOI] [Google Scholar]
6. Akintelu SA, Folorunso AS, Oyebamiji AK. Phytochemical and antibacterial investigation of Moringa oleifera seed: experimental and computational approaches. Eclética Química J. 2021;46(2):17-25. [View at Publisher] [DOI] [Google Scholar]
7. Abdulahi SK, Dada EO, Adebayo RO. Histopathological Effects of Seed Oil of Moringa oleifera Lam. on Albino Mice Infected with Plasmodium berghei (NK65). Adv J Grad Res. 2022;11(1):71-9. [View at Publisher] [DOI] [Google Scholar]
8. Muhammed D, Dada EO, Alo AA. Antibacterial Property of Ethanolic Leaf Extract of Eucalyptus citriodora Hook on Clinical and Typed Isolates of Escherichia coli. South Asian J Res Microbiol. 2018;2(1):1-8. [View at Publisher] [DOI] [Google Scholar]
9. Ijarotimi OS, Adeoti OA, Ariyo O. Comparative study on nutrient composition, phytochemical, and functional characteristics of raw, germinated, and fermented Moringa oleifera seed flour. Food Sci Nutr. 2013;1(6):452-63. [View at Publisher] [DOI] [PMID] [Google Scholar]
10. Donkor A, Oduro-Mensah D, Ani E, Ankamah E, Nsiah S, Mensah DE, et al. In vitro Anti-Plasmodial Activity of Aqueous and Ethanolic Extracts of Moringa oleifera and Phyllanthus amarus. Int J Biol Chem. 2015;9(4):198-206. [View at Publisher] [DOI] [Google Scholar]
11. Wang J, Li Y, Sun H. Lipopolysaccharide - a Target for the Development of Novel Drugs Being Aimed at Gram-Negative Bacteria. Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2015;32(4):910-3. [View at Publisher] [PMID] [Google Scholar]
12. Abu El-Wafa WM, Abd El-All WS. Effect of Moringa oleifera Seed Oil on Antimicrobial Activity of some Antibiotics against some Pathogenic Gram Negative Bacteria. Int J Curr Microbiol Appl Sci. 2015;4(5):140-51. [View at Publisher] [Google Scholar]
13. Abdulkadir AR, Hasan MM, Jahan MS. Antimalarial, antioxidant, antimicrobial properties of Moringa Oliefera Lam: A review. Aust J Crop Sci. 2018;12(06):905-8. [View at Publisher] [DOI] [Google Scholar]
14. Makanjuola OO, Dada EO, Ekundayo FO. Antibacterial Activities of Moringa oleifera (Lam.) on Coliforms Isolated from some Surface Waters in Akure, Nigeria. FUTA J Res Sci. 2013;9(1):63-71. [View at Publisher]
15. Vergara-Jimenez M, Almatrafi MM, Fernandez ML. Bioactive Components in Moringa Oleifera Leaves Protect against Chronic Disease. Antioxidant. 2017;6(4):91. [View at Publisher] [DOI] [PMID] [Google Scholar]
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