In Vitro Assessment of Antibacterial Activity of Some Plant Extracts in Bovine Subclinical Mastitis

Abstract

Present study was undertaken to evaluate in-vitro antibacterial activity of Azadirachta indica (Neem) leaves , Curcumin longa (Turmeric) rhizome and Targetes erecta (Marigold) petals against pathogens of subclinical mastitis in cattle (Bos indicus) and buffalo (Bubalis bubalis). In-addition, in the present study we also determine the phytochemical analysis of Azadirachta indica, Curcumin longa, Targetes erecta and to determine oxidative stress parameters in milk samples of subclinical mastitic animals. For this study we collected 110 milk samples from LRC, SVPUA&T; Daurala Veterinary Hospital and nearby Village of Meerut District. Out of 110 samples, 94 samples are positive for bacterial isolates and 65 samples were positive for CMT, depicting an overall 59.09% prevalence of subclinical mastitis (SCM) and showed more than 2.5 lakh SCC cells/ ml of milk as compared to healthy animals <1.5 lakh SCC. Staphylococcus spp. was confirmed by Mannitol Salt Agar and about 42 samples were positive for Staphylocoocus spp. while E. coli was confirmed by PCR-based 556 base pair band formation and 23 samples were – positive for E. coli. Phytochemical screening of methanol extract of Azadirachta indica (neem) leaves reveal the presence of glycosides, flavonoids, alkaloids and saponin, tannins, phenols, reducing sugar, while carbohydrate, terpenoid, and anthraquinones were absent. Phytochemical screening of methanol extract of Curcuma longa (Turmeric) rhizome reveal the presence of glycosides, flavonoids, saponin, tannins, phenols, reducing sugar, carbohydrate, terpenoid, and anthraquinones while steroids, reducing sugars, phenolic compound, and alkaloids were absent. Phytochemical screening of methanol extract of Tagetes erecta (marigold) petals reveal the presence of glycosides, flavonoids, phenols, reducing sugar, carbohydrate, anthraquinones, phenolic compound, and alkaloids while saponin, tannins, steroids, terpenoid were absent. In vitro antibacterial activity of Azadirachta indica (neem), Curcuma longa (Turmeric) rhizome, Tageteserecta (marigold) petals against Staphylococcus aureus and E.coli. indicated average zone of inhibition of neem extract against Staphylococcus aureus is 12.5mm, 15.5mm, 14.5mm, 12.5mm, at 500mg/ml, 250mg/ml,125mg/ml, 62.5mg/ml, respectively as compared standard drug Streptomycin show 14.5 mm zone of inhibition at 10µg. The average zone of inhibition of neem extract against E. coli was 11.5mm, 13.5mm, 14.5mm, 10.5mm, 10mm at 500mg/ml, 250mg/ml,125mg/ml, 62.5mg/ml, 31.25mg/ml, respectively. And the average zone of inhibition of curcumin extract against Staphylococcus aureus is 11.5mm, 13.5mm, 14.5mm, 10.5mm, at 500mg/ml, 250mg/ml,125mg/ml, 62.5mg/ml, respectively while the standard drug Streptomycin show 14.5mm zone of inhibition. The average zone of inhibition of curcumin extract against E.coli was 11.5mm,13.5mm,13mm, 11.5mm,10.5mm at 500mg/ml,250mg/ml,125mg/ml,62.5mg/ml,31.25mg/ml, respectively. The average zone of inhibition of marigold extract against Staphylococcus aureus is 11.5mm, 13mm, 14mm,11.5mm, at 500mg/ml, 250mg/ml, 125mg/ml, 62.5mg/ml, respectivel in comparison to Streptomycin show 14.5 mm zone of inhibition .The average zone of inhibition of marigold extract against E.coli is 11.5mm, 11.5mm, 13.5mm, 11.5mm, 9mm at 500mg/ml, 250mg/ml, 125mg/ml, 62.5mg/ml, 31.25mg/ml respectively. In the present study, significant increase LPO and Total protein levels in milk of subclinical mastitis cow while GSH level was significantly low in SCM group of cow indicated oxidative stress in animals. No significant alteration in SOD and catalase activity in milk of SCM as well as control groups of cow was observed. Result of present study concluded that Staphylococcus and E Coli were major causative agents of SCM in cow and buffalo and responsible for oxidative stress inducer in mammary glands and all three herbal plants extracts such as-Azadirachta indica, Curcumin longa and Tagetes erecta possess promising antibacterial action against these causative agents, in vitro