https://doi.org/10.5061/dryad.1jwstqk1w

Description of the data and file structure

Two types of supplementary data files have been uploaded:
1. Figures 1–18 show the results of the preliminary antimicrobial activity of the non-polar extracts of Magnolia virginiana L. flowers from Saudi Arabia.

The detailed methodology and results are as follows:

Methodology
Test Organisms
The following test organisms were used: S. aureus ATCC 29213, S. aureus-CI, MRSA-1, MRSA-2, S. epidermidis ATCC 12228, S. saprophyticus ATCC 43867, S. pneumoniae ATCC 49619, E. faecalis ATCC 29212, B. cereus ATCC 10876, E. coli ATCC 25922, K. pneumoniae ATCC 27736, P. aeruginosa ATCC 9027, S. typhimurium ATCC 13311, S. flexneri ATCC 12022, P. vulgaris ATCC 6380, P. mirabilis ATCC 29906, C. albicans ATCC 10231, and A. niger ATCC 6275. All test organisms (ATCC) were procured from Microbiologics, a Biotechnology Company situated in, the USA, and three clinical isolates (S. aureus-CI, MRSA-1, and MRSA-2) were collected from the Microbiology Laboratory Department, King Saud Hospital, Unaizah, Saudi Arabia.

Procedure
The preliminary antimicrobial activity of non-polar extracts of M. virginiana L. flowers was determined using the disc diffusion method (Qureshi et al. 2021; Qureshi et al. 2022). Stock solutions of n-hexane extract (A) and diethyl ether extract (B) were prepared in their respective extraction solvents (n-hexane and diethyl ether) at a concentration of 250 mg/mL. Each diluted extract (20 µL) was dispensed onto sterile test discs. Each paper disc consisted of 5 mg of plant extract, while the negative control discs consisted of 20 µL of n-hexane (H) and diethyl ether (D)/disc. The inoculum of each organism was prepared in sterile tryptic soy broth (TSB), and the turbidity of each suspension was adjusted to equivalent to 0.5 MacFarland standard. Then, 100 µL of each adjusted inoculum was dispensed individually and separately onto the surfaces of the respective test media plates, and the suspensions were evenly spread using sterile swabs. The prepared discs were then placed on the surfaces of the inoculated plates. All the plates were incubated at a temperature of 35 ± 2°C for 24 h for bacteria and 48 h for fungi. Following the incubation period, the diameters of the inhibitory zones were measured using a millimeter (mm) scale, and the tests were performed in triplicate. The results are expressed as mean ± standard deviation (SD) of three replicates.

Results
The results indicated that both non-polar plant extracts displayed remarkable antimicrobial activities against the majority of tested pathogens at a concentration of 5 mg/disc. However, the results further indicated that diethyl ether extract is a better antimicrobial drug candidate than n-hexane extract.
Antibacterial screening results showed that all the tested bacteria are susceptible to both plant extracts, except K. pneumoniae ATCC 27736, P. aerugenosa ATCC 9027, S. flexneri ATCC 12022, P. vulgaris ATCC 6380, and P. mirabilis ATCC 29906, which showed resistance to n-hexane plant extract. Both the extracts showed the highest inhibitory effect on S. saprophyticus ATCC 43867, with a ZID of 14.0 ± 0.3 mm and 20.0 ± 0.3 mm, respectively (Table 1 and Figures 1-16).
Antifungal screening results revealed that both plant extracts exhibited substantial antifungal activity against the tested fungi at a concentration of 5 mg/disc. The results further indicated that diethyl ether extract has more potent antifungal activity than n-hexane extract; the zones of inhibition for C. albicans ATCC 10231 are 11.0 ± 0.4 for n-hexane extract and 16.0 ± 0.3 mm for diethyl ether extract, while the zones of inhibition for A. niger ATCC 6275 are 8.0 ± 0.2 for n-hexane extract and 16.0 ± 0.3 mm for diethyl ether extract, respectively (Table 1 and Figures 17-18). Thus, based on the preliminary antimicrobial activity results, it can be concluded that diethyl ether extract is a more potent antimicrobial extract than n-hexane extract.

Table 1. Preliminary antimicrobial activity of non-polar plant extracts of M. virginiana flowers.

Note: Each test was performed in triplicates. All results are presented as mean ± SD. (A) n-hexane extract, (B) diethyl ether extract, (H) n-hexane control, and (D) diethyl ether control. *CI = Clinical isolate. ZID = Zone of inhibition diameter

Figures 1-18. Preliminary antimicrobial activity of non-polar plant extracts of M. virginiana flowers.
(1) S. aureus ATCC 29213
(2) S. aureus-CI
(3) MRSA-1
(4) MRSA-2
(5) S. epidermidis ATCC 12228
(6) S. saprophyticus ATCC 43867
(7) S. pneumoniae ATCC 49619
(8) E. faecalis ATCC 29212
(9) B. cereus ATCC 10876
(10) E. coli ATCC 25922
(11) K. pneumoniae ATCC 27736
(12) P. aeruginosa ATCC 9027
(13) S. typhimurium ATCC 13311
(14) S. flexneri ATCC 12022
(15) P. vulgaris ATCC 6380
(16) P. mirabilis ATCC 29906
(17) C. albicans ATCC 10231
(18) A. niger ATCC 6275

Reference
Qureshi, K. A., Bholay, A. D., Rai, P. K., Mohammed, H. A., Khan, R. A., Azam, F., Jaremko, M., Emwas, A. H., Stefanowicz, P., Waliczek, M., Kijewska, M., Ragab, E. A., Rehan, M., Elhassan, G. O., Anwar, M. J., & Prajapati, D. K. (2021). Isolation, characterization, anti-MRSA evaluation, and in-silico multi-target anti-microbial validations of actinomycin X2 and actinomycin D produced by novel Streptomyces smyrnaeus UKAQ_23. Scientific Reports, 11(1), 14539. https://doi.org/10.1038/s41598-021-93285-7

Qureshi, K. A., Imtiaz, M., Parvez, A., Rai, P. K., Jaremko, M., Emwas, A. H., Bholay, A. D., & Fatmi, M. Q. (2022). In Vitro and In Silico Approaches for the Evaluation of Antimicrobial Activity, Time-Kill Kinetics, and Anti-Biofilm Potential of Thymoquinone (2-Methyl-5-propan-2-ylcyclohexa-2, 5-diene-1,4-dione) against Selected Human Pathogens. Antibiotics, 11(1), 79. https://doi.org/10.3390/antibiotics11010079

2. Datasheet file containing comprehensive statistical analyses of the antimicrobial activity of non-polar extracts from Magnolia virginiana L. flowers collected in Saudi Arabia.