© by PSP Volume 31– No. 08/2022 pages 7535-7542 Fresenius Environmental Bulletin 7535 ANTIBACTERIAL ACTIVITY, PHYTOCHEMICAL ANALYSIS AND FT-IR ANALYSIS OF Salix Nigra PLANT EXTRACT AGAINST GRAM POSITIVE AND GRAM NEGATIVE BACTERIA Usaal Tahir 1 , Muhammad Fakhar 1 , Mariam Zameer 1 , Uzma Yasmeen 1 , Maham Mazhar 1 , Abu Hassan 1 , Ayesha Rafique 1 , Nureen Zahra 1 , Khadija Gilani 1 , Sobia Alyas 1 , Aroosh Shabbir 1 , Qurban Ali 1,2,* 1 Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore Pakistan 2 Department of Plant Breeding and Genetics, Faculty of Agricultural Sciences, University of the Punjab Lahore, Pakistan ABSTRACT Antimicrobial resistance is one of the major is- sue in medical world, so the most important step in microbiological research is to find out the new anti- microbial compounds that have minimal side effects. Several plants, including Salix nigra, are known to possess antimicrobial activity and have biological compounds that are used to treat ailments from the beginning of human civilization. The aim of this study was to evaluate the anti- bacterial activity and presence of secondary metabo- lites in Salix nigra plant extract. Antibacterial activity of ethanolic plant extract was estimated against pathogenic gram positive (Staphylococcus haemolyticus, Bacillus cereus, Staphylococcus aureus) and gram negative bacteria (Escherichia coli) by using agar well diffusion meth- ods. The maximum antibacterial activity was ob- served with Staphylococcus aureus (Gram positive) that made zone of inhibition of 18 mm. Furthermore, the presence of several phytochemicals including al- kaloids, resins and phenols was confirmed. It is concluded that ethanolic plant extract has tremendous antimicrobial activity against patho- genic microorganisms, especially against Staphylo- coccus aureus. This finding will encourage the ethno-pharmacological usage of Salix nigra. KEYWORDS: Antibacterial activity, Zone of Inhibition, Salix nigra, FTIR INTRODUCTION Medicinal plants have been used for the formu- lation of native therapeutic drugs in Pakistan for a very long time [1]. Several medicinal plants are be- ing utilized by local pharmaceutical companies in Pakistan as indigenous botanical drugs. Herbal plants are common in traditional treatment, and mil- lions of citizens rely on them around the world [2, 3]. According to the World Health Organization (WHO), natural compounds are used by 80 percent of the global population for medical care [4]. This is mostly due to the assumption that traditional reme- dies have fewer side effects as well as being a safer alternative to modern synthetic pharmaceuticals for treating human ailments [5]. Phyto-compounds iso- lated from medicinal herbs have a high level of effi- cacy against infectious illnesses [6]. Plants' medici- nal potential is mostly based on secondary-metabo- lites such as alkaloids, tannins, flavonoids, phenol compounds as well as steroid chemicals which may have an antibacterial effect against infectious dis- eases [7]. These secondary metabolites impose sev- eral beneficial health effects by providing anti-oxi- dant, anti-inflammatory, anti-cancer and antimicro- bial activities [8]. Ethno-veterinary medicines are also often used as an element of a society's approach to enhancing animal health as well as offering basic-veterinary care, which is especially prevalent in rural regions [9]. Plants belonging to different families have been used to treat many ailments. Echinops amplexicaulis has species in Southern & Eastern Europe, Tropical- North as well as East-Africa, and also in Asia [10]. Ugandan traditional healers use the whole root of this shrub to treat HIV/AIDS as well as related ill- nesses [11]. The most commonly mentioned applica- tion is for the treatment of inflammation, discomfort, fever, as well as respiratory tract diseases such as cough as well as sore throat [12]. Ruta chalepensis grows in tropical and subtropical climates. The ex- tracts of R. chalepensis leaf extract are commonly used as a cure for gastrointestinal diseases, head- aches, and rheumatism. Its diuretic, anti-inflamma- tory, as well as anti-spasmodic effects have also been observed [13, 14]. Antibiotic resistance is rapidly growing, mak- ing it more difficult to treat bacterial infections in both animals and humans. Because resistant micro- organisms acquire resistance behavior, even sophis- ticated treatments have failed to comply with them