Antifungal activity from Ocimum gratissimum L. towards Cryptococcus neoformans

Abstract

Cryptococcal infection had an increased incidence in last yearsCryptococcal infections have increased dramatically over the last years. This high incidence can be due in large part to the explosion of acquired immune deficiency syndrome (AIDS) epidemic around the world and the use of more potent immunosuppressive agents by increasing numbers of solid organ transplant recipients (Mitchell & Perfect 1995, Dromer et al. 1996.Cryptococcal meningitis, the most common infection of cryptococcosis is usually chronic and uniformly fatal if untreated (Collazos 2003). Some antifungal drugs, such as polyene macrolides (amphotericin B) and azoles (itraconazole and fluconazole) are currently used in antifungal therapies with certain limitations due to side effects as toxicity and emergence of resistant strains (Terrel 1999, Saag et al. 2000. The lack of response to treatment and resistance in vitro to fluconazole, the drug that now commands maintenance treatment protocols for AIDS patients has began to emerge with Cryptococcus neoformans var. neoformans in immunocompromissed patients undergoing prolonged azole treatment (Alves et al. 1997, Momoff & Parrish 2003 The medicinal plants have been used for several purposes including antimicrobial effects and have showed inhibition of growth to fungi. Caryocar brasiliensis, plant widely distributed in Brazil, has in vitro activity against Paracoccidioides brasiliensis and C. neoformans while Hyptis ovalifolia, plant native from Brazilian cerrado, has inhibitory effect on dermatophytes (Souza et al. 2002). We are interested on antifungal activity of Ocimum gratissimum, plant known as alfavaca cravo, which has presented in vitro inhibitory effect against bacteria as Staphylococcus aureus, Escherichia coli, and some fungi as dermatophytes (Lima et al. 1993, Nakamura et al. 1999.The occurrence of cryptococcosis in Goiânia and its importance in immunocom-promised patients justify in studying Cryptococcus species in this city localized in the Brazilian midwest region. In this paper the antifungal activity of ethanolic crude extract, ethyl acetate, hexane and chloroformic fractions, essential oils and eugenol from O. gratissimum leaves towards 25 isolates of C. neoformans, important pathogen commonly found in our geographic area , was investigated. Chemical analysis of essential oil -Oil sample analysis was performed on a Shimadzu QP5050A gas chromatograph interfaced to a mass spectrometer (GC/MS) instrument employing the following conditions: fused silica capillary column (CBP-5; 30 m x 0.25 µm x 0.25 µm) which was programmed as follows: 60ºC for 2 min and then up to 240ºC at 3ºC/min, then to 270ºC at 10ºC/min ending with a 10 min at 270ºC. The carrier gas was He at a flow rate of 1 ml/min, split mode, with ratio of 1:5, and injection volume of 1 µl in CH 2 Cl 2 and the ionization voltage, 70 EV. The calculation of the retention indexes was made through co-injection with C 8 -C 32 n alkanes series (Van Den Doll & Kratz 1963). Identification of the oil constituents was made based on the ...

Antimicrobial activity of essential oils of <i>Ocimum gratissimum</i> l. from different populations of Kenya

“…This implies that pure eugenol from O. gratissimum could show higher inhibition than the crude essential oils (Table 2). This was also observed by Lemos et al (2005).…”

“…The essential oils from all the populations showed activity on both Gram negative and Gram positive bacteria in addition to the fungi (Candida albicans) as shown by their inhibition zones ( Table 2). The difference in activity of the essential oils from the different populations could be attributed to variation of the chemical composition of the essential oil of O. gratissimum according to geographical distribution (Lemos et al, 2005).…”

GC—MS analysis of the essential oil of Ocimum gratissimum L. growing desolately in South India

“…The compound eugenol was reported in high and low amount along with diverse chemotypes from different region of world [15,[19][20][21][22][23][24][25][26][27][28][29][30][31]. It is interesting to note that, in earlier report [15], the compounds eugenol (75.1%) and terpinolene (14.2%) were reported in high amount from cultivated plant of O. gratissimum.…”

“…In traditional medicine, the leaves of O. gratissimum have been used as a general tonic and antidiarrhea, and for the treatment of conjunctivitis, skin infections, bronchitis, headaches, fever, sunstroke, and influenza [3,4]. Diverse pharmacological activities, viz., anthelmintic [5], antiinflammatory, analgesic [6], immunostimulatory [7], cardiovascular [8], antimutagenic [9], antimalarial [10], antidiarrheal [11,12], antidiabetic [13], an-tioxidant [14,15], cytotoxic [16], and antimicrobial [15,[17][18][19], have been reported from the extract and essential oil of O. gratissimum. The major compound of the essential oil of O. gratissimum from different regions [15,[19][20][21][22][23][24][25][26][27][28][29][30][31] is represented in Table I.…”

Caracterização farmacognóstica das folhas e sementes de Albizia lebbeck (L.) Benth. (Fabaceae)

“…Requerimentos para segurança e eficácia do uso de produtos vegetais têm sido demonstrados (Bast et al, 2002;Silveira et al, 2008;Nascimento et al, 2009). Outra abordagem dada às pesquisas com plantas medicinais é a investigação do potencial antibacteriano e antifúngico, na busca de novos agentes antimicrobianos (Gayoso et al, 2005;Lemos et al, 2005;Navickiene et al, 2006;Ferronatto et al, 2007;Nascimento et al, 2007;Packer & Luz, 2007;Coutinho et al, 2008;Silva Junior et al, 2009).…”