Jurnal Sain Peternakan Indonesia Available at https://ejournal.unib.ac.id/index.php/jspi/index DOI: https://doi.org/10.31186/jspi.id.15.2.142-147 P-ISSN 1978-3000 E-ISSN 2528-7109 Volume 15 Nomor 2 edisi April-Juni 2020 142 | Antibacterial potency of P. ostreatus extract from fruting body...(Badarina et al., 2020) Antibacterial Potency of Pleurotus ostreatus Extract from Fruiting Body and Its Solid Substrate on Staphyllococcus aureus I. Badarina a1 , D. Evvyernie b , E. N. Herliyana c , L. K. Darusman d , and T. Toharmat b a Major Program of Animal Nutrition and Feed Science, Graduate School, Bogor Agricultural University 1 Departement of Animal Husbandary, Agriculture Faculty, Bengkulu University b Department of Nutrition and Feed Technology, Fac. of Animal Science, Bogor Agricultural University c Department of Silviculture, Fac. of Forestry, Bogor Agriculture University d Departement of Chemistry, Faculty of Mathematics and Natural Science, Bogor Agriculture University Corresponding email: irmabadarina@unib.ac.id ABSTRACT The objective of this research was to evaluate the antibacterial potency of ethanol extract from fruiting body of Pleurotus ostreatus and Its solid substrate made from coffee husk and sawdust on the growth of Staphylococcus aureus ATCC 25922. The extract of Ganoderma lucidum fruiting body and Tetracycline antibiotic paper disk 30μg/disk were used as control. The samples were extracted by using maceration method in 30% ethanol solution. The extracts were diluted with sterile distilled water to concentration 500, 1000, and 5000ppm. The result showed that the ethanol extracts from fruiting body of Pleurotus ostreatus and Ganoderma lucidum and the extracts of coffee husk and sawdust substrate fermented by Pleurotus ostreatus could inhibit the growth of bacteria for all the concentration. There was a significant difference in diameter of cleared zones between Tetracycline antibiotic disc 30μg and the ethanol extracts of the samples (p<0.01). The diameter of cleared zones among the sample extracts and each dilution concentrations were not a significant difference (p>0.05). Tetracycline was sensitive to S.aureus ATCC25922, while all the extracts were resistant. This study confirmed that there were the antibacterial potency of mushroom extracts from the fruiting body and also its solid substrates. Key words : antibacterial, extract, Pleurotus ostreatus, fruiting body, solid substrate. INTRODUCTION Mastitis is a major problem of the dairy animals. It is an inflammation of mammary gland parenchyme which is caused by bacteria and its toxins (Sharma et al., 2011). Mastitis influence the quantity and the quality of milk, be a food safety problem and an economic losses. The change of mammary tissues due to mastitis leading the progressive change to the secretory apparatus and resulting in the loss of milk production. The closed association between milk production and somatic cell count (SCC) has been increasing used to estimate production loss (Barlett et al., 1990). Mastitis changed milk composition and milk quality. The mastitis or elevated SCC is associated with a decrease in lactose, α-lactalbumin, and fat in milk because of reduced synthetic activity of mammary tissue (Harmon, 1994). Milk from mastitis udder or with high SCC causes arise in whey protein and a decrease in casein, resulting in a considerable lower cheese yields. Shorter shelf life and adverse milk flavor are other consequences of high SCC (Sharif and Muhammad, 2008). Several pathogens can cause mastitis but Staphylococcus aureus is the most frequently contagious pathogen. S. aureus secretes several toxins contributing to the pathogenesis of mastitis and also plays a role in foodborne disease, even with pasteurized milk because of the thermostable enterotoxins (Contreras et al., 2007). Because of that it is important to get the way to erradicate S. aureus in dairy animals. The antibiotic usage is one of the way that often used to treat mastitis. But due to the growing concern of antibiotic resistance and residual effect to animals and humans, the use of antibiotic have already been banned or been minimized. A potential alternative to antibiotic is natural or traditional medicine and mushroom have been exploited for the treatment of many diseases.