Bangladesh Journal of Pharmacology Volume: 16; Number 2; Year 2021 Cite this article as: Segaran G, Sathiavelu M. Antibacterial activity of an ornamental plant Hippeastrum fos- teri. Bangladesh J Pharmacol. 2021; 16: 49-51. Antibacterial activity of an ornamental plant Hippeastrum fosteri Sir, The genera Hippeastrum Herb. is native to South American and belongs to the family Amaryllidaceae with about 60 species. This genus has long been used to treat tumor, hemorrhoid and bronchial asthma (Tallini et al., 2017). One of the species Hippeastrum elegans shows anticholinesterase activity due to the presence of galantamine to treat Alzheimer's disease. Other bio- active alkaloids are narciclasine, sanguinine and pseu- dolycorine (de Paiva et al., 2021). 3-O-acetyl-narcissi- dine (bioactive alkaloid) was isolated from H. puniceum and showed antifeedant against the poly-phagous insect Spodoptera littoralis. H. fosteri is an ornamental plant used for decorative purposes. This study aimed to conduct the antibacterial activity of H. fosteri leaves. The fresh and healthy leaves from the study plant were collected from the Ranipet, Tamilnadu, India. Leaves were washed twice with tap water to remove dust particles and air-dried for 2 weeks. Then, the dried leaves were grounded to fine powder with a blender machine. Water, methanol, ethyl acetate and dichloro- methane were the solvents with four different polarities used. About one gram of dry leaf powder was soaked in 100 mL of each solvent and Milli-Q water in a 250 mL conical flask and kept in a shaker of 120 rpm at 37ºC overnight. Solvent and aqueous extracts were separated from the solid residue by filtration using Whatman No. 1 filter paper and evaporated for one week to obtain the leaf crude extracts. Phytochemical constituents of the leaf were analyzed by the method described previously (Shankar et al., 2018). Antibacterial properties of leaf crude extracts were screened by the agar well diffusion method (Atef et al., 2019). The antimicrobial properties of crude extracts were tested against Bacillus subtilis, Enterococcus fecalis, Staphylococcus aureus (Gram positive) and Escherichia coli, Pseudomonas fluorescence, Klebsiella pneumoniae (Gram negative bacteria). The test pathogens were pre- cultured in nutrient broth and used for this study. Fresh Muller Hinton agar plates were prepared and streaked with test pathogen. A sterile cork borer was used to make wells in agar plates containing inoculums. Three different concentrations (25, 50, 100 µg/mL) of crude extracts were subjected for analysis. Further, 100 µL of each extracts were added to their appropriate wells. The A Journal of the Bangladesh Pharmacological Society (BDPS) Bangladesh J Pharmacol 2021; 16: 49-51 Journal homepage: www.banglajol.info; www.bdpsjournal.org Abstracted/indexed in Academic Search Complete, Agroforestry Abstracts, Asia Journals Online, Bangladesh Journals Online, Biological Abstracts, BIOSIS Previews, CAB Abstracts, Current Abstracts, Directory of Open Access Journals, EMBASE/Excerpta Medica, Global Health, Google Scholar, HINARI (WHO), International Pharmaceutical Abstracts, Open J-gate, Science Citation Index Expanded, SCOPUS and Social Sciences Citation Index ISSN: 1991-0088; DOI: 10.3329/bjp.v16i2.52655 Letter to the Editor This work is licensed under a Creative Commons Attribution 4.0 International License. You are free to copy, distribute and perform the work. You must attribute the work in the manner specified by the author or licensor Table I Antibacterial activity of different extracts of H. fosteri against bacterial pathogenic strains Extract Concentra- tion (µg/mL) Zone of inhibition (mm) Gram positive Gram negative Bacillus subtilis Enterococcus fecalis Staphylococcus aureus Escherichia coli Pseudomonas fluorescence Klebsiella pneumoniae Aqueous 25 - - - 16 - - 50 12 20 13 100 14 31 20 Methanol 25 14 - - - - 1 50 21 12 100 24 13 15 Ethyl acetate 25 - - 7 16 - 8 50 8 8 2 8 100 20 8 9 31 17 8 Dichloromethane 25 11 - 12 - - 11 50 12 14 13 100 17 15 16 Standard (mg) 10 35 46 35 40 33 25 plates were incubated at 37°C for 18 hours. After the incubation period, the zone of inhibition was measured in diameter to determine the antimicrobial activity. Ciprofloxacin is used as the positive control (standard). Phytochemical screening of the leaf extracts of H. fosteri revealed the presence of phenol, flavonoids, tannins and anthraquinone glycosides (data are not shown). The resulting outcome of agar well diffusion assay showed the plant extract had antibacterial property. The highest zone of inhibition was observed on E. coli for aqueous extract with 32 mm inhibition at 100 µg/ mL (Table I). The ethyl acetate extract of H. fosteri leaves showed antibacterial activity (Figure 1). It had promi- nent antibacterial properties against E. fecalis, S. aureus, E. coli, P. fluorescence and K. pneumoniae. When com- pared with the other three extracts, methanol exhibited lower antibacterial activity against tested strains. This is the first report on the antibacterial activity of H. fosteri. The methanol extract showed inhibition against only two pathogenic microbes B. subtilis and K. pneumoniae and exhibited lower antibacterial activity. Whereas, the other three extracts exhibited significant antibacterial activity against most of the test pathogens. A study demonstrated the cytotoxic activity of fresh bulbs of H. vittatum against five human cell lines OVCAR3 epithelial ovarian cancer, RXF393 renal cell carcinoma, H460 non-small cell lung carcinoma, MCF7 breast cancer and HT29 colon adenocarcinoma (Silva et al., 2008). Both n-butanol and dichloromethane extracts and alkaloids of H. vittatum demonstrated strong activity against the cell lines (Silva et al., 2008). When compared to untreated diabetic rats, the oral adminis- tration of mucilage of H. vittatum bulbs at 150 mg/kg reduced induced hyperglycemia by 45.4% and 62.0% after 2 and 4 hours. At the concentration of 250 mg/kg, elevated blood glucose levels were reduced by 57.4% and 65.7% after 2 and 3 hours (Attia et al., 2021). The authors thank the Vellore Institute of Technology for providing chemicals and lab facilities to carry out this research. Gayathri Segaran and Mythili Sathiavelu School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India. Corresponding author: email: smythili@vit.ac.in References Atef NM, Shanab SM, Negm SI, Abbas YA. Evaluation of anti- microbial activity of some plant extracts against antibiotic susceptible and resistant bacterial strains causing wound infection. Bull Natl Res Cent. 2019; 43: 1-11. Attia EZ, Khalifa MF, Fahim JR, Kamel MS. Anti-diabetic potential of mucilage from Hippeastrum vittatum bulbs in streptozotocin-induced diabetic rats. S Afr J Bot. 2021; 136: 100-04. de Paiva JR, de Queiroz Souza AS, Pereira RD, Ribeiro PR, 50 Bangladesh J Pharmacol 2021; 16: 49-51 Figure 1: Antibacterial activity of ethyl acetate extract of H. fosteri leaves against bacterial pathogens A B Alves Filho EG, e Silva LM, Zocolo GJ, de Brito ES, Alves DR, de Morais SM, Tavares J. 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