ABSTRACT: This study determined the extraction conditions, chemical composition, and antimicrobial activities of the essential oils of Citrus nobilis. The results illustrated that soaking in the 9% (w/v) NaCl solution for 2 h with a sample and solvent ratio of 1:3 (w/v) and a subsequent extraction time of 45 min yielded the highest extraction efficiency, reaching 3.66% (w/w). The main chemical components of the essential oils were limonene (90.42%), β-myrcene (4.7%), and α-pinene (1.22%). The minimum inhibitory concentration (MIC) at the density of 5x104, 5x105, and 5x106 cells/mL of Escherichia coli were 100, 125, and 125 mg/mL, respectively; for Staphylococcus aureus were 75, 100, and 125 mg/mL, respectively; and for Bacillus cereus were 50, 75, and 100 mg/mL, respectively. The minimum bactericidal concentration (MBC) at densities of 5x104, 5x105, 5x106 cells/mL of E. coli were 175, 225, 225 mg/mL, S. aureus were 150, 200, 225 mg/mL, and B. cereus were 125, 175, 200 mg/mL, respectively. The inhibitory activities of Aspergillus flavus of orange essential oils according to the agar dilution method at concentrations of 0.025-0.1%) on the 5th day were 8.84-30.61%. ABSTRACT conditions composition nobilis 9 w/v wv w v (w/v 13 1 3 1: 4 efficiency 366 66 3.66 w/w. ww w/w . (w/w) 90.42%, 9042 90.42% , 90 42 (90.42%) βmyrcene β myrcene 4.7%, 47 4.7% 7 (4.7%) αpinene α pinene 1.22%. 122 1.22% 22 (1.22%) MIC (MIC 5x104 x 5x105 5x10 cellsmL cells mL 12 mgmL mg mg/mL respectively 75 50 10 MBC (MBC E 175 S 150 B 20 0.0250.1% 002501 0.025 0.1% 0 025 0.025-0.1% th 8.8430.61%. 8843061 8.84 30.61%. 8 84 30 61 8.84-30.61% 36 6 3.6 (w/w 904 90.42 (90.42% 4.7 (4.7% 1.22 (1.22% 5x1 5 17 15 0250 0.0250.1 00250 0025 0.02 01 0.1 02 0.025-0.1 8430 8.8430.61% 884306 884 8.8 3061 30.61% 8.84-30.61 3. 90.4 (90.42 4. (4.7 1.2 (1.22 5x 0.0250. 002 0.0 0. 0.025-0. 843 8.8430.61 88430 88 8. 306 30.61 8.84-30.6 90. (90.4 (4. 1. (1.2 0.0250 00 0.025-0 8.8430.6 8843 30.6 8.84-30. (90. (4 (1. 0.025- 8.8430. 30. 8.84-30 (90 ( (1 8.8430 8.84-3 (9 8.843 8.84-
RESUMO: Este estudo teve como objetivo determinar as condições de extração, composição química e atividades antimicrobianas dos óleos essenciais de Citrus nobilis. Os resultados demonstram que a imersão na solução de NaCl a 9% (p/v) por 2 h com uma proporção de amostra e solvente de 1:3 (p/v) e um tempo de extração subsequente de 45 min produziu a maior eficiência de extração, atingindo 3,66 % (p/p). Os principais componentes químicos dos óleos essenciais foram limoneno (90,42%), β-mirceno (4,7%) e α-pineno (1,22%). A concentração inibitória mínima (CIM) na densidade de 5x104, 5x105 e 5x106 células/mL de Escherichia coli foram 100, 125 e 125 mg/mL, respectivamente, e para Staphylococcus aureus foram 75, 100 e 125 mg/mL, respectivamente, e para Bacillus cereus foram 50, 75 e 100 mg/mL, respectivamente. A concentração bactericida mínima (MBC) em densidades de 5x104, 5x105, 5x106 células/mL de E. coli foram 175, 225, 225 mg/mL, S. aureus foram 150, 200, 225 mg/mL e B. cereus foram 125, 175, 200 mg/mL, respectivamente. As atividades inibitórias de Aspergillus flavus dos óleos essenciais de laranja, de acordo com o método de diluição em ágar nas concentrações 0,025-0,1%, no dia cinco foram 8,84-30,61%. RESUMO nobilis 9 p/v pv p v (p/v 13 1 3 1: 4 366 66 3,6 p/p. pp p/p . (p/p) 90,42%, 9042 90,42% , 90 42 (90,42%) βmirceno β mirceno 4,7% 47 7 (4,7% αpineno α pineno 1,22%. 122 1,22% 22 (1,22%) CIM (CIM 5x104 x 5x10 célulasmL células mL 12 mgmL mg respectivamente 10 50 MBC (MBC E 175 S 150 B 20 laranja 0,0250,1%, 002501 0,025 0,1%, 0 025 0,025-0,1% 8,8430,61%. 8843061 8,84 30,61%. 8 84 30 61 8,84-30,61% 36 6 3, (p/p 904 90,42 (90,42% 4,7 (4,7 1,22 (1,22% 5x1 5 17 15 0250 0,0250,1% 00250 0025 0,02 01 0,1% 02 0,025-0,1 8430 8,8430,61% 884306 884 8,8 3061 30,61% 8,84-30,61 90,4 (90,42 4, (4, 1,2 (1,22 5x 0,0250,1 002 0,0 0,1 0,025-0, 843 8,8430,61 88430 88 8, 306 30,61 8,84-30,6 90, (90,4 (4 1, (1,2 0,0250, 00 0, 0,025-0 8,8430,6 8843 30,6 8,84-30, (90, ( (1, 0,0250 0,025- 8,8430, 30, 8,84-30 (90 (1 8,8430 8,84-3 (9 8,843 8,84-