Screening of Some Egyptian Plant Extracts for Biological Activity Against Some Pathogenic Bacteria

Abstract

Plants and plant by-products are now gaining attractiveness in treatment of bacterial infections and food preservation. The objective of this study was to assess antibacterial activity of some Egyptian plant and plant by-products against the locally pathogenic isolates from patients having infectious diseases in our country. Screening of antibacterial activity of ethanol, methanol and hexane extracts of some plants: grape leaves (Vitis vinifera), mulberry leaves (Morus alba), mallow leaves (Corchorus olitorius) and lemon leaves (Citrus limon) toward Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella sp., were investigated. Antibacterial activity was performed by the agar disc diffusion method. The ethanol and methanol extract of tested plant leaves showed promising antibacterial activities against both Gram-positive and Gram-negative tested bacterial isolates due to its great ability to extract those polyphenolic and biological active compounds from natural sources which effectively act against broad spectrum bacteria. Ethanol followed by methanol were found to be the best solvents of choice to extract natural products to get maximum health and medicinal benefits. The results revealed that the extraction efficiency increase with polarity increasing of the solvents, hence the highest extraction done with ethanol and methanol and the lowest extraction with nonpolar solvent n-hexane did not exhibit any activity against all the tested bacteria. Irradiation at 5 and 10 kGy did not significantly affect the antibacterial activity of all tested plant leaves. Results indicate the potential of these plants for further work on isolation and characterization of the active compounds responsible for antibacterial activity and its exploitation as therapeutic agents 378 Arab Univ. J. Agric. Sci., 25(2), 2017

Valorisation of black mulberry and grape seeds: Chemical characterization and bioactive potential

“…Black mulberry (Morus nigra L.), which originates from China, is cultivated for its fruits in Southern Europe and Southwest Asia (Mosayebi & Tabatabaei Yazdi, 2018). Mulberry fruits and leaf wastes have been widely studied (Abdel-Hamid et al, 2017;Huang et al, 2011;Koyuncu, 2004;Li et al, 2017;Mena et al, 2016;Natić et al, 2015;Okatan, 2018;Raman et al, 2016;Zhang et al, 2018); however, mulberry seeds have been underexploited, compared to grape pomace and seeds. A substantial amount of mulberry fruits is processed into juice and juice concentrates, indeed the mulberry production in Turkey exceeded 74 thousand tons (Tomas et al, 2015).…”

“…In a recent study, Abdel-Hamid et al (2017) revealed the antibacterial properties of grape and mulberry leaf extracts against Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhimurium. Additionally, Huang et al (2011) suggested that anthocyanins from mulberry fruits might be used to prevent gastric carcinoma formation and Peixoto et al (2018) described Vitis vinifera L. seed winery wastes as potential cytotoxic agents against MCF-7 breast adenocarcinoma and HeLa cervical carcinoma tumour cells.…”

“…Several authors have deal separately with the chemical or the bioactive characterisation of grape or mulberry wastes (Abdel-Hamid et al, 2017;Aldubayan, 2018;Dopico-García et al, 2007;Poveda et al, 2018). However, few have addressed the individual characterization and the multiple bioactive properties of grape (Peixoto et al, 2018), and mulberry seeds (Kim et al, 2010).…”

Antibacterial effect of ethanolic Morus alba Linn. leaf extract against mastitis-causing Escherichia coli and Staphylococcus aureus in vitro

“…Mulberry also has economic importance for the sericulture industry, as it is traditionally used to feed silkworms in Asia (Lamberti et al, 2019). Previous studies have demonstrated several medicinal properties of mulberry plants, including antihyperglycemic (Chen et al, 2018), antioxidant (Polumackanycz et al, 2019) and antibacterial (Abdel-Hamid et al, 2017) activities. Extracts of M. alba L. leaves have also shown beneficial effects against bacteria isolated from humans, such as S. aureus and E. coli (minimum inhibitory concentration [MIC] 0.32 mg/mL and minimum bactericidal concentration [MBC] 0.64 mg/mL) (Abdel-Hamid et al, 2017).…”

“…Previous studies have demonstrated several medicinal properties of mulberry plants, including antihyperglycemic (Chen et al, 2018), antioxidant (Polumackanycz et al, 2019) and antibacterial (Abdel-Hamid et al, 2017) activities. Extracts of M. alba L. leaves have also shown beneficial effects against bacteria isolated from humans, such as S. aureus and E. coli (minimum inhibitory concentration [MIC] 0.32 mg/mL and minimum bactericidal concentration [MBC] 0.64 mg/mL) (Abdel-Hamid et al, 2017). A study of leaf extracts from two Morus species (M. alba and M. rubra L.) showed effects against gram-negative and gram-positive bacterial ATCC strains, including S. aureus, S. epidermidis, S. pyogenes, E. faecalis, Propionibacterium acnes, E. coli, P. aeruginosa, Acinetobacter baumannii, Proteus mirabilis, and K. pneumoniae, with MIC and MBC values of 15.75-252.00 mg/mL (Miljkovic et al, 2018).…”