To address the rising challenge of resistance to traditional antibiotics and to bolster microbial management in the dominions of food safety and antibiotic effectiveness, recent explorations have been conducted into the bioactive phytochemicals, utilizing eco-friendly methodologies. This study focuses on the potential utility of Rhazya stricta and Azadirachta indica, indigenous plant species of Saudi Arabia, in combatting foodborne bacteria across the pharmaceutical and food sectors. The dried leaf powders of both plants underwent methanol extraction, evaporation via a rotary evaporator, and subsequent dissolving in a 1% dimethyl sulfoxide (DMSO) solution. The bioactive constituents were analyzed through gas chromatography-mass spectrometry (GC/MS), revealing a higher presence of bioactive compounds (32 compounds) in A. indica compared to R. stricta (15 compounds). R. stricta’s methanolic extract demonstrated superior efficacy against the tested bacterial strains (Salmonella enteritidis, Staphylococcus aureus, Salmonella typhimurium, and Escherichia coli) compared to A. indica. These findings were compared against six antibiotics: cefoxitin (FOX), cephalothin (KF), cotrimoxazole (TS), gentamicin (GM), augmentin (AUG), and ampicillin (AP). Furthermore, both plant extracts exhibited inhibitory effects on microbial lipase, amylase, and protease enzymes. In conclusion, further investigations at the molecular and biochemical levels are warranted in future studies to elucidate the precise mechanisms underlying the antibacterial efficacy of these naturally occurring plant species.

To address the rising challenge of resistance to traditional antibiotics and to bolster microbial management in the dominions of food safety and antibiotic effectiveness, recent explorations have been conducted into the bioactive phytochemicals, utilizing eco-friendly methodologies. This study focuses on the potential utility of Rhazya stricta and Azadirachta indica, indigenous plant species of Saudi Arabia, in combatting foodborne bacteria across the pharmaceutical and food sectors. The dried leaf powders of both plants underwent methanol extraction, evaporation via a rotary evaporator, and subsequent dissolving in a 1% dimethyl sulfoxide (DMSO) solution. The bioactive constituents were analyzed through gas chromatography-mass spectrometry (GC/MS), revealing a higher presence of bioactive compounds (32 compounds) in A. indica compared to R. stricta (15 compounds). R. stricta’s methanolic extract demonstrated superior efficacy against the tested bacterial strains (Salmonella enteritidis, Staphylococcus aureus, Salmonella typhimurium, and Escherichia coli) compared to A. indica. These findings were compared against six antibiotics: cefoxitin (FOX), cephalothin (KF), cotrimoxazole (TS), gentamicin (GM), augmentin (AUG), and ampicillin (AP). Furthermore, both plant extracts exhibited inhibitory effects on microbial lipase, amylase, and protease enzymes. In conclusion, further investigations at the molecular and biochemical levels are warranted in future studies to elucidate the precise mechanisms underlying the antibacterial efficacy of these naturally occurring plant species.

Allelopathy refers to both beneficial and harmful effects of one plant on another plant by the release of chemicals from plant parts through leaching, root exudation, volatilization, residue decomposition and other processes in both natural and agricultural systems. Tithonia diversifolia contains allelochemicals that inhibit or stimulate growth of agricultural crops. A study was conducted to investigate the allelopathic effects of fresh shoot aqueous extracts of T. diversifolia on the germination of seeds and growth of young seedlings of Spiderplant (Cleome gynandra) under laboratory and glasshouse conditions. Seeds of C. gynandra were germinated in sterilizedpetri-dishes lined with two layers of whatman no.1 filter papers moistened with 10ml of fresh shoot aqueous extracts of T. diversifolia (0%, 25%, 50%, 75%, and 100%) in Department of Botany laboratory of Maseno University. Number of seeds germinating each day was recorded and germination percentage calculated for each treatment at the end of the experiment. Plumule and radicle lengths were also measured. In the glasshouse, individual plants were grown in 4.5 litre plastic pots containing soil. The treatments allocated to the pots involved 4 different concentrations: 400ml aqueous shoot extracts of T. diversifolia at 25%, 50%, 75% and 100% and tap water (control). The treatments were replicated five times and the pots laid out in a completely randomized design. The fresh shoot aqueous extracts of T. diversifolia did not show significant (p > 0.05) allelopathic effect on germination of seeds of C. gynandra. However, higher shoot extracts concentration stimulated the germination of the seeds. Plumule and radicle lengths were significantly (p < 0.05) inhibited by higher concentrations of the shoot extracts. The aqueous shoot extracts of T. diversifolia significantly stimulated shoot height, leaf area, number of leaves, fresh weight and dry weight of C. gynandra. The study indicated that aqueous fresh shoot extracts of T. diversifolia have both stimulatory and inhibitory effects on spiderplant (C. gynandra,) germination and growth.