ANTIMICROBIAL EFFECT OF BLACK MUSTARD SEED EXTRACT ON SOME PATHOGENIC BACTERIA

This study evaluated the antimicrobial potential of black mustard seed (Brassica nigra) extracts against pathogenic bacteria, including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pyogenes. Mustard seed oil was extracted using aqueous, ethanolic, and methanolic methods and tested using the disc diffusion method to determine its efficacy. The Minimum Inhibitory Concentration (MIC) of the extracts was also determined, while phytochemical analyses revealed the presence of alkaloids, flavonoids, tannins, saponins, and phenols. Results indicated that the aqueous extract exhibited the highest antimicrobial activity, with significant inhibition at lower concentrations (100 mg/ml) compared to ethanolic and methanolic extracts, which required higher concentrations (150 mg/ml) to achieve similar effects. Among the phytochemicals, alkaloids and flavonoids were most abundant, contributing to the extract's antimicrobial properties. This study underscores the medicinal value of Brassica nigra, highlighting its potential as a natural antimicrobial agent and its application in treating microbial infections. Furthermore, the findings support the need for local cultivation and utilization of mustard seeds to enhance public health and food safety practices.1.1 Background of the study For many centuries, plants, barks, roots, spices and many more natural agricultural resources have been used greatly in the treatment and prevention of several disease cases, especially by the Asian and African natives (Ghani et al., 1998). In recent time, modem and sophisticated equipments have been made available for the extraction of different important active constituents of several agricultural materials for use in pharmaceutical processes and in the food industries (Obi et al., 2009). Mustard seed has traditional dietary and medicinal applications as an anti-infective agent (Obi et al., 2006). Invitro evidence of the antimicrobial activity of fresh and dried mustard extracts against many bacteria, fungi and viruses supports these applications (Cimanga et al., 1991) This study was meant to investigate the individual effect of crude mustard extract in the inactivation of human pathogenic bacteria and atmospheric pathogens such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus pyogenes .Mustard refers to several Brassica species that are valued for their spicy and pungent dried seeds. The reported life zone for mustard is 5 to 27 degrees centigrade with an annual precipitation of 0.3 to 4.2 meters and have a soil pH of 4.2 to 8.3. the active antimicrobial component of mustard crude extract is allyl isothiocyanate (AITC) and also contains some ally! cyanide and carbon disulfide (Simon et al., 1984). Mustard seed and seed products are used extensively in the food industry, in meats, sausages, processed vegetables, and relishes (Entani et al., 1998);probably because of its antimicrobial properties. The antimicrobial properties of natural substances have long been recognized and utilized across various cultures for their therapeutic benefits (Yadav et al., 2017). Among these, black mustard seed stands out as a potent source of antimicrobial compounds, presenting a promising avenue for exploration in both traditional and modern medicine. Black mustard seed (Brassica nigra ) has been a staple ingredient in culinary and medicinal practices for centuries, revered for its distinct flavor and numerous health benefits (Singh et al., 2017). Beyond its culinary applications, traditional medicine systems such as Ayurveda and traditional Chinese medicine have long utilized black mustard seed for its antimicrobial and anti-inflammatory properties (Pandey et al., 2020). These historical uses provide a solid foundation for exploring its potential in modern medical contexts. Recent scientific studies have begun to shed light on the mechanisms underlying the antimicrobial activity of black mustard seed. Research indicates that its efficacy against microbial pathogens is attributed to bioactive compounds such as glucosinolates, phenolic compounds, and essential oils present in the seeds (Sultana et al., 2018). These compounds exhibit varying degrees of antimicrobial activity against a wide range of bacteria, fungi, and even some viruses. To fully harness the antimicrobial benefits of black mustard seed, it is essential to understand the most effective methods for extracting these active compounds. Various extraction techniques, including solvent extraction, steam distillation, and supercritical fluid extraction, have been explored to isolate the bioactive constituents from the seeds (Wani et al., 2019). Each method offers unique advantages in terms of efficiency, yield, and preservation of bioactivity, but selecting the optimal extraction process is crucial to maximizing the therapeutic potential of black mustard seed.