Phoenix dactylifera L. fruit is a staple food in most Arabic-speaking countries. It’s composed of a soft, sweet pericarp covering a seed. Different parts of the P. dactylifera L palm tree can be used for medicinal purposes, such as dried leaves, fruit, pollen, seed, and tree bark extracts. A P. dactylifera L palm fruit consists of several components, including skin, pulp, endocarp, and seed (Shanableh and Radeef 2020). There are over 5000 different types of P. dactylifera L worldwide, depending on their kind and maturation stage. P. dactylifera L palms contain various nutritive and cosmetic components, and these bioactive substances are used in business and medicine (El-Far et al. 2021).

Studies have shown that palm P. dactylifera L. have the potential to be antioxidants, antimutagenic, antibacterial, anti-inflammatory, antihyperlipidemic, gastroprotective, hepatoprotective, nephroprotective, anticancer, antifibrotic, antiproliferative, and immunostimulant. Additionally, researchers found that different parts of palm P. dactylifera L. have distinct beneficial chemicals. Nutraceutical substances such as anthocyanins, phenolics, sterols, carotenoids, and flavonoids have been shown to have free radical scavenging properties and to shield people from oxidative damage. Several studies have confirmed the presence of these substances in P. dactylifera L. palms (El-Kholy et al. 2019).

Gc-mass analysis was used to determine the phytochemical composition of ethanolic extract of P. dactylifera L. pits. The analysis revealed the presence of active compounds such as phenols, pentaoxacyclopen, octaethylene glycol monododecyl ether, 15,15’-Bi-1,4,7,10,13-pentaoxacyclohexadecane,á-D-Gluco pyranosiduronic acid, 5-[3,4-bis[(trimethylsilyl)oxy]phenyl]-3-methyl, and tridecane. According to El-Far et al. (2021), P. dactylifera L. palms have all the essential amino acids and contain phenolic and flavonoid substances, including polyphenols and flavonoids with antibacterial properties. Polyphenols can be further classified as benzoic acid derivatives and cinnamic acid derivatives. Some examples of benzoic acid derivatives are p-hydroxybenzoic acid, vanillic acid, protocatechuic acid, syringic acid, and gallic acid. On the other hand, examples of cinnamic acid derivatives are P-coumaric acid, o-coumaric acid, ferulic acid, and caffeic acid. Flavonoids, which are secondary metabolites of polyphenolic plants, are divided into many subgroups, including fava-3-ols, anthocyanidins, isoflavones, flavanones, flavanols, and flavones. Phenolic chemicals have been studied as major microbial growth inhibitors for spoilage and harmful microorganisms, particularly in the food and clinical research sectors. Phenols also have the potential to act as anti-quorum sensing agents and as inhibitors of the microbes associated with food and wound infections that form biofilms and produce toxins (El-Kholy et al. 2019).

P. dactylifera L. plum fruit is well-known for its antimicrobial properties due to its antibacterial, antifungal, and antiviral characteristics, as reported in studies by Godugu et al. (2020). In recent study, PDPE was tested against various pathogenic microorganisms, and all of them were inhibited. The highest inhibition zone diameter (IZD) of 35.0 mm was recorded for S. aureus ATCC 5638, while the lowest IZD was observed for S. typhi and S. sonnei with an IZD of 26.0 mm. As for the fungal strains, A. flavus, P. chrysogenum, and A. niger, they didn’t exhibit any zone of inhibition, but there was a failure of spores and conidia formation for all the fungi.

P. dactylifera L. plum fruit has been found to have antibacterial properties against a variety of bacteria such as E. coli, P. aeruginosa, B. subtilis, B. cereus, and S. aureus and S. abony, as reported in many studies including those by Samad et al. (2016). This antibacterial activity is attributed to the high phenolic content of P. dactylifera L. palms, which also possess antifungal properties. Previous studies have shown that P. dactylifera L. palm extracts have antifungal properties against several types of A. niger, F. oxysporum, and C. albicans(El-Azim et al. 2015).

The MIC values of PDPE were tested using concentrations of 250–1000 µg/ml against the pathogenic bacteria. S. aureus ATCC 5638 and E. coli ATCC 8379 exhibited an MIC value of 500 µg/ml, whereas B. cereus ATCC 11778, E. faecalis ATCC 7080, S. typhi DSM 17058, and S. sonnei DSM 5570 exhibited an MIC value of 250 µg/ml PDPE. As investigated previously, at PDPE concentrations ranging from 500 to 1000 µg/ml the antibacterial spectrum activity showed 100% activity, whereas it was 83.3% at a concentration of 250 µg/ml. Whereas at 125 µg/ml, there was no antibacterial activity. The MBC values ranged between 500 and 1000 µg/ml of PDPE against the tested bacterial strains. B. cereus ATCC 11778, E. faecalis ATCC 7080, and S. typhi DSM 17058 exhibited 500 µg/ml of PDPE MBC value. S. aureus ATCC 5638, S. sonnei DSM 5570, and E. coli ATCC 8379 have an MBC value of 1000 µg/ml (Hussain et al. 2019). The antibacterial spectrum activity of PDPE at equal to 100% of 1000 µg/ml, whereas it was 66.7% at a concentration of 500 µg/ml. At 125–250 µg/ml concentrations there was no antibacterial activity against all pathogen strains. As mentioned in the previous study MIC values of P. dactylifera L. pits ranged from 7.80 to 4.65 mg in Ajwa and Mabroom, respectively. Hussain et al. (2019) results showed that the ethyl acetate extract of Khalas and Khodari dates inhibited S. aureus with an inhibition zone diameter of 20.0 mm and MIC of 10 mg/ml, while the Abu Mann pit extract both inhibited S. aureus and decreased the E. coli population. After treatment with Ajwa extracts, the inhibitory zone’s diameter was 15.0, 16.0, and 18.0 mm, and the MICs were 7.5 and 5.0 mg/ml. Different P. dactylifera L. pit extracts had MICs ranging from 2.5 to 10.0 mg/ml when tested against S. aureus ATCC 29213 and E. coli ATCC 25922. In the same line, Ajwa methanolic extract had antibacterial activity for E. coli, B. cereus, S. aureus, and Serratia marcescens(Samad et al. 2016). However, Shakiba et al. (2011) stated that for the methanol extract of Mazafati dates, no inhibitory zone was seen with E. coli PTCC 1330, E. coli PTCC 1270, E. coli PTCC 1399, and Serratia marcescens. Additionally, Khatami and Shahram (2015) found that P. dactylifera L. pit aqueous extract dramatically reduced Acinetobacter baumannii ATCC 19606 and Klebsiella pneumonia PCI 602, while also decreasing the Rhizoctonia solani AG2_2 population at 25 µg/ml.

In a different study of Al-Daihan and Bhat (2012) it was found that P. dactylifera L. pit extract has antibacterial activity against various microbiological pathogens such as P. aeruginosa, B. subtilis, S. aureus, E. coli, S. pyogenes, and S. flexeneri. However, the aqueous extract showed little effect on P. aeruginosa and exhibited only a weak antibacterial effect against all tested pathogens. The study of Sadeq et al. (2021) indicated methanol and acetone pollen extracts of P. dactylifera pits were shown to moderately reduce the growth of both G + ve and G-ve bacteria. Another investigation carried out by Sarraf et al. (2021) using four different P. dactylifera L. pits revealed that ethanolic and methanolic extracts from the pits exhibited an inhibitory impact on S. aureus while showing no effect on E. coli. The extracts’ minimal inhibitory and minimal bactericidal concentrations for S. aureus were found to be 1.56–3.125 mg/ml and 3.125–12.5 mg/ml, respectively. The presence of active compounds such as flavanols, flavonoid glycosides, and cinnamic acids was found to be the main factor causing P. dactylifera L. pit antimicrobial effect (Zidan et al. 2023).

The PDPE biofilm inhibition showed that S. aureus ATCC 5638 had the highest PDPE inhibition percentage (1000 µg/ml) at 98.59%, followed by B. cereus ATCC 11778 at 94.12%. The lowest antibiofilm influence was observed with E. coli ATCC 8379 at 74.46%. In a previous study, Ajwa dates caused a significant inhibition of 70.5% and 54.19% against Staphylococcus sp. and Salmonella sp. respectively, while Safawi date has an antibiofilm effect against Staphylococcus sp. and Pseudomonas sp. with 65.78% and 45.5%, respectively. The study of Qasim et al. (2020) indicated the effective role of Ajwa and Khalas dates in preventing biofilm formation in B. subtilis and Pasteurella multocida.

Although there are limited studies on the antiviral properties of P. dactylifera L. palm pits, a recent investigation revealed that the highest non-toxic concentrations (CC50) of PDPE against Herpes simplex virus (HSV1) was 123.0 µg/ml with a 50% reduction in viral activity. Similarly, a recent study found that palm leaf extract had antiviral properties against the SARS-CoV-2 virus (Ahmad et al. 2022).

To conclude, Phoenix dactylifera L. pits ethanolic extract (PDPE) have significant antimicrobial, antibiofilm and antiviral activities. The study found that PDPE significantly influenced pathogenic microorganisms, with the most significant being S. aureus ATCC 5638. PDPE showed a 100% antibacterial spectrum activity against tested pathogenic bacteria, with MIC values ranging from 250 to 1000 µg/ml. S. aureus had the highest percentage of inhibition followed by B. cereus and E. coli. The highest non-toxic PDPE doses were found to be 123.0 µg/ml.