Physicochemical and microbiological evaluation of acidmodified native starch derived from Borassus aethiopum (Arecaceae) shoot

Purpose: To evaluate the physicochemical properties and microbiological quality of Borassus aethiopum shoot acid-modified starch (AMS) for potential pharmaceutical applications.Methods: Modification of Borassus aethiopum native starch (NS) was carried out using 6 % w/v HCl at 37 ± 2 oC for 192 h. The AMS was characterised for their morphological, micromeritics, rheological, thermal properties as well as their microbiological quality using standard protocols.Results: AMS demonstrated increased aqueous solubility, crystallinity and slight increase in flow properties. There was a reduction in swelling and hydration capacities, amylose content as well as viscosity of the modified starch. Scanning electron microscopy analysis showed that the integrity of the modified starch granules were maintained and there was no disruption of the granular structure. Fourier transform infrared spectrophometer data confirmed the hydrolysis of NS with the increase in the intensity of the O-H stretch. AMS met United States Pharmacopoeia requirements in terms of microbiological quality, however, there was presence of Aspergillus niger.Conclusion: Modification of Borassus aethiopum shoot starch by acid treatment led to desirable improvement in some of its physicochemical properties which could improve its functional properties in pharmaceutical industries.Keywords: Native starch, Acid-modified starch, Borassus aethiopum, Microbiological quality, Physicochemical propertie

Detection of efflux pump activity among clinical isolates of Staphylococcus and Micrococcus species

Purpose: To detect efflux pump activity (EPA) and screening a suspected efflux pump inhibitor (EPI) [1- (3-(trifluoromethyl)benzyl]-piperazine (TFMBP)], which could help in reducing multi-drug resistance (MDR).Methods: Eighteen isolates, viz, 14 S. aureus, 2 S. lentus, 1 S. xylosus and 1 Micrococcus species from various hospital infections of admitted patients were screened for antibiotics susceptibility to 11 classes of antibiotics including oxacillin and β-lactamase production. Efflux pump activity (EPA) was determined by minimum inhibitory concentration (MIC) technique in the presence and absence of TFMBP, the isolates were also screened for MDR genes.Results: All the isolates were resistant to ampicillin (10 μg) and penicillin (10 μg), but sensitive to bacitracin (10 μg). Majority of the isolates were MDR 12/18 (66.7 %), 10 (55.6 %) were inducible β- lactamase producers and 3 (16.7 %) were intrinsic β-lactamase producers. Seven (38.9 %) were resistant to oxacillin and also produced carbapenemase enzyme. Eight (66.7 %) of the 12 MDR isolates gave evidence of EPA with TFMBP. However, no MDR genes were detected.Conclusion: Staphylococcus and Micrococcus species exhibit EPA in antibiotic resistance while a suitable EPI such as TFMBP when combined with specific antibiotics could help combat this menace.Keywords: [1-(3-(Trifluoromethyl)benzyl]-piperazine, Efflux pump activity, Oxacillin resistant S. aureus, Multidrug resistant, Carbapenemas