1 Introduction

Staphylococcus aureus is a gram-positive, facultative anaerobic bacterium that appears in grape-like clusters. It causes community and hospital-acquired infections, such as bacteremia, osteoarticular, and skin infections. The treatment of S.aureus related infections is becoming challenging due to the emergence of multidrug resistant strains such as Methicillin-resistant S. aureus (MRSA). As a result, S.aureus strains have become resistant to various antibiotics such as Methicillin, nafcillin, oxacillin, and cephalosporin (Liu et al., 2005). Similarly, Cryptococcus neoformans is a pathogenic unicellular yeast that causes cryptococcal meningitis in AIDS patients. Normally, it infects one million people each year around the world. Previously, cryptococcosis was treated efficiently with the help of many commercially available antifungal agents, such as Amphotericin B, Flucytosine, and Fluconazole. However, over time and due to extensive use, the fungus has developed resistance to these antifungals, rendering them ineffective (Almeida et al., 2015).

Plant extracts have been used since the dawn of human civilization to treat various ailments because they are a rich source of many phytochemicals such as alkaloids, phenols, and tannins. So, many plant-derived phytochemicals can be used as a harmless and cheaper alternative strategy for the treatment of S.aureus associated infections. Bismarckia nobilis is an evergreen dioecious palm with a single thick trunk and unique silver-blue, rounded, and fan-shaped leaves (Mitchell, 2012). It is generally known as a silver palm due to its color. Only limited data is available regarding the medicinal use of Bismarckia in history. Some studies have shown that the methanolic extract of Bismarckia nobilis has smooth muscle relaxant potential in diarrhea, hypertension, and asthma (Saqib et al., 2019). Bismarckia plant has also been used by the people of Madagascar for oral health care (Ranjarisoa et al., 2016). The antioxidant potential of B.nobilis fiber was examined by Schauss and Voon (Schauss and Voon, 2006). Choysia ternata is a species of flowering plant belonging to the genus Rutaceae, commonly known as Mexican orange blossom or Mexican orange. Radulović et al., (2013a) studied the effect of methyl and isopropyl N-methyl anthranilate from C.ternata on experimental anxiety and depression in mice. The anti-inflammatory potential of a hybrid plant of C.ternata, Choisya Aztec pearl, was assessed by Carvalho et al. (2014). Leitão et al. (2017) isolated quinolinic alkaloids from Choysia species by high-speed countercurrent chromatography and studied their antioxidant activity. Beaucarnea recurvata, also known as ponytail palm, is an evergreen perennial plant belonging to the Asparagaceae family. It is a native Mexican plant grown in Europe and many other parts of the world as an ornamental plant. Any medicinal use of this plant has not been reported so far, but Eskander et al. (2011) isolated thirteen steroidal components from the leaves of B.recurvata using NMR and mass spectroscopy. Lastly, Chamaedora cataractarum, also known as cat palm, is a small palm native to Central America and southern Mexico. To date, no data is available to suggest the medical importance of Chamaedora cataractarum plant.

The current study aims to prepare plant extracts in n-hexane and 70 % methanol to determine the antibacterial and antifungal activity against isolated S. aureus and C. neoformans strains, respectively.

2 Methodology

3 Results

3.2

3.2 Characterization of bacterial strains

3.2.1

3.2.1 Biochemical characterization of bacterial strains

All strains formed rounded yellow-coloured colonies on MSA plates (Fig. 1). These colonies were purified by quadrant streaking until well-isolated colonies were obtained. All bacterial strains were gram-positive cocci in the form of grape-like clusters when viewed under the 100X lens of the compound microscope. Moreover, all strains were catalase-positive and oxidase-negative (Supplementary data Table 2).

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Fig. 1

Biochemical characterization of S. aureus. (a) Growth of bacterial isolates on Mannitol salt agar (MSA) as rounded yellow-coloured colonies; (b) Appearance of bacterial isolates as clusters of purple-stained gram-positive cocci; (c) No purple coloration in oxidase negative, indicating absence of cytochrome C oxidase enzyme; (d) Bubble formation at the addition of 3% H₂O₂ indicated the presence of catalase.

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3.2.2

3.2.2 PCR amplification of 16S rRNA gene of S.aureus

The reaction mixture used for PCR amplification consisted of 2.5U of Taq polymerase, 1X buffer, 0.15 mM dNTPs, 1.5 Mm MgCl₂, primers (785F and 907R), and 1–2 µg of template DNA. The PCR reaction was allowed to run under optimized conditions (Supplementary data Figure 1).

3.2.3

3.2.3 Analysis of PCR products

PCR products were run on 1.5 % agarose gel along with a 100 bp ladder. DNA bands of about 144 bp were observed between 200 and 100 bp ladder segments (Fig. 2).

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Fig. 2

Analysis of V3 region of eight S.aureus strains by agarose gel electrophoresis. Lane 1 represents a 100 bp DNA ladder. Whereas lane 2–8 represents PCR products of S.aureus strains.

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3.2.4

3.2.4 Antibacterial activity by agar well diffusion assay

After 24 h of incubation, the size of the zone of inhibition of different concentrations of plant extracts was measured in mm. Two plant extracts, BN and CT, formed clear zones of inhibition against the isolates of S. aureus tested (Fig. 3). At 100 mg/mL concentration, BN and CT yielded inhibition zones measuring 12.1–13.1 mm and 13.1–15.1 mm, respectively (Table 1).

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Fig. 3

Antibacterial activity of (B. nobilis) BN and (C. ternata) CT plants against isolated S.aureus strain. DMSO was used as a negative control. (a) BN and CT inhibited bacterial growth and formed zones of inhibition measuring 15 ± 0.1 mm and 12.25 ± 0.25 mm, respectively, each at a 100 mg/ml concentration. (b) BN and CT inhibited bacterial growth and formed zones of inhibition measuring 13.1 ± 0.1 mm and 13.1 ± 0.1 mm, respectively, each at a 100 mg/ml concentration. (c) BN and CT inhibited bacterial growth and formed zones of inhibition measuring 14.1 ± 0.1 mm and 12.05 ± 0.25 mm, respectively, each at a 100 mg/ml concentration. (d) BN and CT inhibited bacterial growth and formed zones of inhibition measuring 15.1 ± 0.1 mm and 12.1 ± 0.1 mm, respectively, each at a 100 mg/ml concentration.

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Table 1 Antibacterial activity against S. aureus: B. nobilis and C. ternata demonstrated antibacterial strong potential against various isolates of S. aureus when assessed by the agar well-diffusion assay. The values are expressed in mm.

S.aureus strains	Zone of inhibition (mm)
	C.ternata	B.nobilis
ASH3	15.1 ± 0.1	12.25 ± 0.25
ASH4	15 ± 0.0	12.5 ± 0.5
ASH5	13.1 ± 0.1	13.1 ± 0.1
ASH6	14.1 ± 0.1	12.05 ± 0.05
ASH7	14.05 ± 0.05	13.1 ± 0.1
ASH8	15.1 ± 0.1	12.1 ± 0.1
ASH2	15 ± 0.0	12.2 ± 0.0
ASH1	13.1 ± 0.1	12.1 ± 0.1

3.3

3.3 Determination of MIC of plant extracts

Three methods were used to determine the MIC of plant extracts, such as agar well diffusion assay, microbroth dilution assay, and MTT reduction assay.

3.3.1

3.3.1 Agar well diffusion assay

After 24 h of incubation, the size of the zone of inhibition of different concentrations of plant extracts was measured in mm. It was found that the zone of inhibition gradually decreased with decreasing concentrations of plant extracts (Fig. 4a, 4b). MIC of the CT plant determined by agar well diffusion assay was in the range of 1.56–3.125 mg/ml, whereas the MIC of the BN plant was in the range of 3.125–6.25 mg/ml (Tables 2a and 2b). All experiments were performed in duplicates, and results were displayed as mean diameter ± SE, where SE represents standard error. See (Fig. 5).

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Fig. 4

Effect of increasing concentration, from 0.78 mg/ml, 1.56 mg/ml, 3.125 mg/ml 6.25 mg/ml, 12.5 mg/ml, 25 mg/ml, to 50 mg/ml, of Choysia ternata extract (CT) and Bismarckia nobilis extract (BN) against S.aureus. (a) CT inhibited bacterial growth and formed zones of inhibition measuring 0 mm, 7 ± 0.0 mm, 8 ± 0.0 mm, 8.5 ± 0.0 mm, 11 ± 0.0 mm, and 12.05 ± 0.15 mm at the concentrations of 0.78 mg/ml, 1.56 mg/ml, 3.125 mg/ml, 6.25 mg/ml, 12.5 mg/ml, 25 mg/ml, and 50 mg/ml, respectively. The size of the zone of inhibition increased with the increasing concentration of plant extracts. (b) BN inhibited bacterial growth and formed zones of inhibition measuring 0 mm, 0 mm, 0 mm, 7.05 ± 0.05 mm, 8.1 ± 0.1 mm, 11.2 ± 0.1 mm, and 12 ± 0.0 mm at the concentrations of 0.78 mg/ml, 1.56 mg/ml, 3.125 mg/ml, 6.25 mg/ml, 12.5 mg/ml, 25 mg/ml, and 50 mg/ml, respectively. The size of the zone of inhibition increased with the increasing concentration of plant extracts.

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Table 2a MIC of Choysia ternata plant extract. Minimum inhibitory concentration of C. ternata against various isolates of S. aureus as determined using the agar well-diffusion assay. All tests were performed in duplicates, and the results were expressed as mean diameter ± SE.

Bacterial strains	Concentration of plant extract mg/ml
	100	50	25	12.5	6.25	3.125	1.56	0.78
ASH3	13.15 ± 0.05	12.05 ± 0.15	11 ± 0.0	8.5 ± 0.0	8 ± 0.0	7 ± 0.0	–	–
ASH4	13.15 ± 0.05	11.1 ± 0.1	7.1 ± 0.1	7.1 ± 0.1	7 ± 0.0	–	–	–
ASH5	13.2 ± 0.1	12.1 ± 0.1	11.05 ± 0.05	10 ± 0.0	9 ± 0.0	8 ± 0.0	7 ± 0.0	–
ASH6	12.15 ± 0.05	11 ± 0.0	10.15 ± 0.05	9.25 ± 0.05	9 ± 0.1	8.0 ± 0.0	–	–
ASH7	13.1 ± 0.1	12.25 ± 0.25	11 ± 0.0	8.1 ± 0.1	7.1 ± 0.1	–	–	–
ASH8	12.05 ± 0.15	11.1 ± 0.1	10.1 ± 0.1	8.0 ± 0.0	–	–	–	–
ASH2	12.1 ± 0.1	12.05 ± 0.05	10.2 ± 0.2	8.05 ± 0.05	–	–	–	–
ASH1	12.1 ± 0.0	11.1 ± 0.1	10 ± 0.0	8.1 ± 0.1	–	–	–	–

Table 2b MIC of Bismarckia nobilis plant extract. Minimum inhibitory concentration of B. nobilis against various isolates of S. aureus as determined using the agar well-diffusion assay. All tests were performed in duplicates, and the results were expressed as mean diameter ± SE.

Bacterial strains	Concentration of plant extract mg/ml
	50	25	12.5	6.25	3.125	1.56	0.78	0.39
ASH3	12.5 ± 0.5	12.1 ± 0.1	12 ± 0.0	7.1 ± 0.1	7.05 ± 0.05	–	–	–
ASH4	12 ± 0.0	11 ± 0.0	7.1 ± 0.1	–	–	–	–	–
ASH5	13.1 ± 0.1	12.2 ± 0.2	10.1 ± 0.1	10 ± 0.0	8.0 ± 0.0	–	–	–
ASH6	12.05 ± 0.05	11.1 ± 0.1	10.3 ± 0.1	10.2 ± 0.2	8.15 ± 0.5	–	–	–
ASH7	13 ± 0.0	12 ± 0.0	11.2 ± 0.1	8.1 ± 0.1	7.05 ± 0.05	–	–	–
ASH8	12.2 ± 0.2	11.5 ± 0.5	10 ± 0.0	8 ± 0.0	7 ± 0.0	–	–	–
ASH2	12.2 ± 0.0	11.5 ± 0.0	10 ± 0.1	9.10.1	7 ± 0.1	–	–	–
ASH1	12.05 ± 0.05	11.1 ± 0.1	10 ± 0.0	8 ± 0.0	–	–	–	–

– sign indicates no inhibition.

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Fig. 5

MIC of different concentrations of B. nobilis (BN) and C. ternata (CT) plant extracts determined by MTT reduction assay. Where rows A = sterility control, B = growth control, C = BN plant extract and ASH6 isolate, D = CT plant and ASH6 isolate, E = BN plant extract and ASH3 isolate, F = CT plant extract and ASH3 isolate, G = BN plant extract and ASH8 isolate and H = CT plant extract and ASH8 isolate. Figure I shows the color of the plate before adding MTT, while figure II shows the development of purple coloration after the addition of MTT.

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3.3.2

3.3.2 Microbroth dilution assay

After 24 h of incubation, 96 well plates containing different concentrations of plant extracts and S.aureus were absorbed in liquid media at 600 nm. MIC was considered as that concentration of plant extract whose absorbance was less than that of growth control and closely related to sterility control. Microbroth dilution assay was more sensitive in measuring MIC of plant extracts. The MIC of C. ternata plant was 0.78–1.56 mg/ml, and the MIC of B. nobilis plant was 1.56–6.25 mg/ml (Table 3a).

Table 3a MIC By Microbroth Dilution Assay. MIC was considered as that concentration of plant extract whose absorbance was less than that of growth control and closely related to sterility control. Microbroth dilution assay was found more sensitive in measuring MIC of plant extracts. Results are reported as mg/ml.

Bacterial strains	MIC mg/ml
	CT	BN
ASH3	1.56	3.125
ASH4	0.78	1.56
ASH5	1.56	3.125
ASH6	1.56	3.125
ASH7	0.78	1.56
ASH8	1.56	6.25
ASH2	0.78	1.56
ASH1	1.56	3.125

3.3.3

3.3.3 MTT reduction assay

96 well plate was used for growing S.aureus in the presence of different concentrations of plant extracts. After 24 h of incubation, cell viability was checked with the help of an MTT solution. 22 µl MTT was added to all test wells. The appearance of purple color indicated the presence of viable bacterial cells. The purple color started fading away with decreasing the concentration of plant extracts until it became light purple or colorless, indicating the absence of viable bacterial cells. The MIC of the C. ternata plant determined by the MTT reduction assay was 1.56–3.125 mg/ml, whereas the MIC of B. nobilis plant was 1.56–6.25 mg/ml (Table 3b).

Table 3b MIC By MTT Reduction Assay. This assay uses MTT solution to check cell viability. Purple color indicates presence of viable bacterial cells. Increasing concentration of plant extract produced a light purple or colorless tinge indicating an absence of live cells. Resulst are reported as mg/ml.

Bacterial strains	MIC mg/ml
	CT	BN
ASH3	1.56	3.125
ASH4	3.125	6.25
ASH5	1.56	3.125
ASH6	1.56	3.125
ASH7	1.56	3.125
ASH8	1.56	3.125
ASH2	3.125	3.125
ASH1	3.125	3.125

MIC = Minimum inhibitory concentration

MTT = 3-(4,5-Dimethylthiazol-2-yl)-2.5-Diphenyltetrazolium Bromide.

CT = Choysia ternate.

BN = Bismarckia nobilis.

3.5

3.5 Determination of antifungal activity of plant extracts

3.5.1

3.5.1 Isolation and identification of C.neoformans

C. neoformans was identified based on colony morphology, microscopic appearance, and urease test (Fig. 6a, b, and c, respectively). It formed mucoid, creamy, and smooth colonies on the SDA medium after one week of incubation at room temperature. Furthermore, C. neoformans appeared as encapsulated, spherical cells lacking hyphae or pseudohyphae. C. neoformans changed the color of the media from yellow to pink due to ammonia production.

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Fig. 6

Morphological Identification of C.neoformans and antifungal activity against it. (a) Colony morphology – formation of mucoid, creamy, and smooth colonies on Sabouraud Dextrose Agar (SDA) medium; (b) Microscopic Appearance – encapsulated, spherical cells lacking hyphae or pseudohyphae; (c) Urease positive indicated by the change in media's color from yellow to pink owing to production of ammonia. (d) Antifungal activity of 70 % methanolic extracts of B. nobilis (BN), C. ternata (CT), B. recurvata (BR) and C. cataractarum(CC) against Cryptococcus neoformans. BN, CT, BR, and CC inhibited fungal growth and formed zones of inhibition measuring 14.25 ± 0.25 mm, 13.25 ± 0.05 mm, 17.35 ± 0.15 mm, and 16.25 ± 0.05 mm, each at a concentration of 100 mg/ml.

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3.5.2

3.5.2 Antifungal activity of plant extracts

70 % methanolic extracts of all plants showed significant antifungal activity against C.neoformans by agar well diffusion assay (Fig. 6d). 100 µl of each plant extract (100 mg/ml) was added to the SDA plate inoculated with 0.5McFarland fungal suspension. After one week of incubation at room temperature, the zone of inhibition was calculated (Table 5).

Table 5 Antifungal activity against C. neoformans. the 70% methanolic extracts of all four indigenous plants demonstrated antifungal activity against the fungus C. neoformans using agar well-diffusion assay. The measurements are expressed in mm.

70 % Methanolic Plant Extracts	Zone of Inhibition (mm)
B. nobilis	14.25 ± 0.25
C. ternata	13.25 ± 0.05
B. recurvata	17.35 ± 0.15
C. cataractarum	16.25 ± 0.05

4 Discussion

Over time, the uncontrolled use of antibiotics has led to the emergence of drug-resistant staphylococcal infections, making their treatment increasingly challenging. The prevalence of multidrug-resistant S. aureus strains is a global issue, with high levels of resistance to multiple antibiotics, including penicillin, ampicillin, oxacillin, and ceftriaxone. Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant global health threat. The estimated global prevalence of MRSA is 14.69 %. The 30-day all-cause mortality rate for bloodstream infections with MRSA is estimated to be 20 % to 40 %. Moreover, the overall mortality rate attributed to Staphylococcus aureus infections was over 1 million deaths in 2019. It is associated with a wide range of infections, including skin and soft tissue infections, endocarditis, osteomyelitis, bacteremia, and lethal pneumonia. These figures underscore the urgent need for continued research and development of effective alternative strategies to combat drug-resistant staphylococcal infections.

The limited effectiveness of certain antibiotics has heightened the importance of alternative treatment approaches, such as phytomedicine, in addressing this critical public health concern. Plant extracts have been traditionally used to treat infectious diseases due to their abundance of effective phytochemicals, which offer an alternative strategy for combating infections. The current study used Bismarckia nobilis and Choysia ternata plants to study their antimicrobial effect. Plant extracts were prepared in 70 % methanol and n-hexane. N-hexane extracts of Bismarckia nobilis and Choysia ternata plants showed antibacterial activity against eight S.aureus isolates. Alam et al. (2020) also studied the antibacterial activity of the silver nanoparticles derived from the seeds of B. nobilis plant by the green method. The anti-inflammatory activity of essential oils, ternanthranin, and two synthetic analogs isolated from C.ternata were also studied (Pinheiro et al., 2015). However, the current study is the first report of the antibacterial activity of B. nobilis and C. ternata leaf extract against any bacterial species. The zone of inhibition of B.nobilis plant extract was 12.1–13.1 mm, and the zone of inhibition of C.ternata plant extract was 13.1–15.1 mm for different S.aureus isolates (Table 1).

After determining antibacterial activity, MIC of B. nobilis and C. ternata plants was determined by agar well diffusion assay, microbroth dilution assay, and MTT reduction assay. Although the MIC determined by all three methods was concordant with each other, microbroth dilution assay was the most sensitive method. So the MIC of the plant determined by microbroth dilution assay was in the range of 0.78–3.125 mg/ml and 1.56–12.5 mg/ml for CT and BN plant extracts, respectively (Table 3a). In order to find the mode of action of these plant extracts, MBC was also calculated to find out the MIC_index value. The MIC_index of BN and CT plants was 0.1248 against S.aureus isolate ASH4 (Table 4a). When the MIC/MBC ratio is ≤ 4, the plant extract is regarded as bactericidal, but if the ratio is ˃ 4, then the plant extract is considered bacteriostatic (Krishnan et al., 2010). Since the value is less than 4, the mode of action of B. nobilis and C. ternata plants is bactericidal. The current investigation is first time reporting the antibacterial activity of these plants against S.aureus. On the other hand, 70 % methanolic extract of all four plants showed antifungal activity against Cryptococcus neoformans fungus, the leading cause of meningitis in AIDS patients. The zone of inhibition of Bismarckia nobilis, Choysia ternata, Chamaedora cataractarum, and Beaucarnea recurvata was 14.25 mm, 13.25 mm, 16.25 mm, and 17.35 mm, respectively (Table 11). The antifungal activity of Lauris nobilis species was reported by Sırıken et al. (2018).

These plants remain largely unexplored for their antimicrobial potential, with limited studies around them. Bismarckia nobilis has been reported as a smooth muscle relaxant. Methanolic extract of B.nobilis is effective for treating diarrhea, hypertension, and asthma because of its spasmodic, antidiarrheal, and vasodilator activities (Saqib et al., 2019). B.nobilis has also been used by the people of Mahajanga, Madagascar, as a mouthwash to treat oral diseases (Ranjarisoa et al., 2016).

GC–MS analysis of C. ternata revealed the presence of the natural compound isopropyl N-methylanthranilate named ternanthranin. Essential oil and ethanolic extract of the C. ternate showed pain-killing activity (Radulović et al., 2011). Antispasmodic and simulative properties of the two compounds isopropyl N‐methylanthranilate and methyl N‐methylanthranilate isolated from C. ternata were also reported (Radulović et al., 2013b). Pinheiro et al. (2015) studied the anti-inflammatory properties of essential oils of C. ternata.

Members of the Arecaceae Family have, however, shown antimicrobial potential. For instance, Farahmandfar et al. (2019) found that the ultrasonic extracts of Arum maculatum (particularly in the ethanol: water (50:50) solvent) had higher extraction yield and antioxidant potential than the maceration extracts. The extracts (water, ethanol, and 50:50 ethanol: water) were active against the tested food-borne pathogens, gram-positive and gram-negative bacterial strains, including S.aureus. Results of the microdilution assay showed that the ultrasonic-assisted ethanol extract (EE-US) was the most effective against S. aureus and had the lowest MIC against it at 12.5 mg/ml. Plant extracts are more effective against Gram-positive bacteria compared to Gram-negative bacteria. This may be due to the differences in the cell wall structure of these two types of bacteria. Studies have shown that plant extracts can cause cell wall disruption and decrease cytoplasmic pH in Gram-positive bacteria, leading to their inhibition. The number and position of phenolic hydroxyl groups, double bonds, and delocalized electrons in plant compounds can also affect their antibacterial activity.

Based on these results, it can be theoretically expected that C.ternata and B.nobilis plant extracts can be used for the treatment of S.aureus associated infections. Similarly, all four plants (Bismarckia nobilis, Choysia ternata, Beaucarnea recurvata, and Chamaedora cataractarum) can be potent antifungal agents for treating Cryptococcal infections. So, we can use these plant extracts for the development of antibiotics. These antibiotics would be economical and safe to use and can serve as potent antifungal and antibacterial agents.

The current study assessed the antibacterial potential of the selected plants since it used eight strains of S.aureus and three different techniques to determine the minimum inhibitory concentration (MIC). However, it presents several limitations. Above all, the selected bacterial strains originate from the same region. To further validate the efficacy of the extracts, they should be tested against drug-resistant strains from different geographical areas (at the global or domestic level). Furthermore, the study does not explore the phytochemical composition of the extracts nor identify the active metabolites. Additionally, the safety or toxicity of the plants used has not been addressed. Moreover, the yield and composition of phytochemicals can be influenced by and, thus, vary due to several factors like growth environment, plant parts, harvest season, and extraction method, potentially influencing its activity.

As mentioned above, the limitations provide a broad path for future prospects. The active plants can be assessed for their efficacy in combatting a wide range of bacterial and fungal pathogens. Bacterial biofilms often pose greater resistance to antibiotics. Plant extracts can be studied for their potential to inhibit biofilm formation. The extracts can also be paired with conventional antibiotics to evaluate their synergistic potential for more effective treatment.

Phytochemical profiles of plant extracts can be analyzed, and the active plant metabolites can be identified through GC–MS or HPLC-MS analysis. Further research can explore the mechanisms of action adopted by the antimicrobial components, paving the way for targeted therapies. The plants can additionally be checked for other biological properties such as anti-viral, anti-cancer, or anti-inflammatory effects. Experimenting with cancer cells and mouse models can assist in identifying additional properties and determining their safety and toxicity status. Moreover, these plant extracts can also be utilized as bio-preservatives in processed food items by preventing the growth of microorganisms and increasing the shelf life of food.

5 Conclusion

In conclusion, the current study highlights the potent antimicrobial attributes of indigenous plants of Bismarckia nobilis, Choysia ternata, Chamaedora cataractarum, and Beaucarnea recurvata. The efficacy of n-hexane and methanolic extracts against S. aureus and C. neoformans, respectively, implicates their therapeutic relevance. The n-hexane extracts of Bismarckia nobilis and Choysia ternate exhibited potent antibacterial activity against S. aureus. Moreover, the methanolic extracts of all four plants displayed potent antifungal activity. The study remains confined to in vitro experiments and sidesteps phytochemical analysis. Analyzing the bioactive constituents of these plant extracts and bridging the gap between in vitro assays and in vivo investigations would enhance the clinical translatability of these findings. In a broader context, our findings contribute to the growing body of knowledge aimed at harnessing the potential of nature's arsenal to develop plant-based therapeutics to mitigate microbial infections.

6 Consent to participate

All authors consent to participate in the manuscript publication

7 Consent for publication

All authors approved the manuscript to be published.

8 Declaration of funding

Researchers Supporting Project Number (RSPD2024R1083), King Saud University, Riyadh, Saudi Arabia.

Author contributions

KM AU and TN conceptualized the research. KM, AL and AR conducted experiment. HY, MA, KAMB, ZA contributed in data acquisition and data analysis, and written the first draft of paper. HMA helped in software and language editing. KM, HY, AU and TN critically revised and improved the manuscript. All authors red and approved the final draft for submission.

CRediT authorship contribution statement

Kausar Malik: Conceptualization, Supervision. Ayesha Liaqat: Data curation, Writing – original draft. Ammara Riaz: Validation, Formal analysis. Humaira Yasmin: Project administration, Resources. Muhammad Asad: Investigation, Formal analysis. Amin Ullah: Conceptualization, Formal analysis, Resources. Khadija Abdul Majid Butt: Methodology, Validation. Zainab Akram: Writing – original draft. Hossam M. Aljawdah: Software, Visualization, Investigation. Tariq Nadeem: Conceptualization, Project administration, Writing – review & editing.