ABSTRACT
Antibiotics are the chemotherapeutic agents that kill or inhibit the pathogenic microorganisms. Re-sistance of microorganism to antibiotics is a growing problem around the world due to indiscriminate and irrational use of antibiotics. In order to overcome the resistance problem and to safely use antibiotics, the correct measurement of potency and bioactivity of antibiotics is essential. Microbiological assay and high performance liquid chromatography (HPLC) method are used to quantify the potency of antibiotics. HPLC method is commonly used for the quantification of potency of antibiotics, but unable to determine the bioactivity; whereas microbiological assay estimates both potency and bioactivity of antibiotics. Additionally, bioassay is used to estimate the effective dose against antibiotic resistant microbes. Simultaneously, microbiological assay addresses the several parameters such as minimal inhibitory concentration (MIC), minimum bactericidal concentration (MBC), mutation prevention concentration (MPC) and critical concentration (Ccr) which are used to describe the potency in a more informative way. Microbiological assay is a simple, sensitive, precise and cost effective method which gives reproducible results similar to HPLC. However, the HPLC cannot be a complete substitute for microbiological assay and both methods have their own significance to obtain more realistic and precise results.
ABSTRACT
The aim of this study was to develop and validate a simple, sensitive, precise and cost-effective one-level agar diffusion (5t1) bioassay for estimation of potency and bioactivity of Levofloxacin in pharmaceutical preparation which has not yet been reported in any pharmacopoeia. Among 16 microbial strains, Bacillus pumilus ATCC-14884 was selected as the most significant strain against Levofloxacin. Bioassay was optimized by investigating several factors such as buffer pH, inoculums concentration and reference standard concentration. Identification of Levofloxacin in commercial sample Levoflox tablet was done by FTIR spectroscopy. Mean potency recovery value for Levofloxacin in Levoflox tablet was estimated as 100.90%. A validated bioassay method showed linearity (r2 ? 0.988), precision (Interday RSD ? 1.05%, between analyst RSD ? 1.02%) and accuracy (101.23%, RSD ? 0.72%). Bioassay was correlated with HPLC using same sample and estimated potencies were 100.90%and 99.37%, respectively. Results show that bioassay is a suitable method for estimation of potency and bioactivity of Levofloxacin pharmaceutical preparations.
ABSTRACT
Eclipta alba (L.) Hassk is small branched annual herbaceous plant with a long history of traditional medicines uses in many countries especially in tropical and subtropical regions. The herb has been known for its curative properties and has been utilized as antimytotoxic, analgesic, antibacterial, antihepatotoxic, antihaemorrhagic, antihyperglycemic, antioxidant, immunomodulatory properties and it is considered as a good rejuvenator too. A wide range of chemical compounds including coumestans, alkaloids, thiopenes, flavonoids, polyacetylenes, triterpenes and their glycosides have been isolated from this species. Extracts and metabolites from this plant have been known to possess pharmacological properties. The present study confirmed the antibacterial potential of aerial parts extracts of Eclipta alba in solvents like acetone, ethanol, methanol, aqueous and hexane against selected gram positive and gram negative bacterial species. The antibacterial studies were done by agar well diffusion methods. The MIC and MBC methods were also used. Hexane extract of showed Eclipta alba high antibacterial activity against S.aureus, B.cereus, E.coli, S.typhi, K.pneumoniae,S.pyogenes and P.aeruginosa. whereas acetone, ethanol, methanol and aqueous extracts showed intermediate activity against S.aureus, B.cereus, E.coli, S.typhi, K.pneumoniae, P.aeruginosa, P.mirabilis and S.pyogenes. The inhibitory activities of all the extracts reported were compared with standard antibiotics (Ciprofloxacin 25 μg/ml). An MIC of 90.0μg/ml shown by E.coli and S.aureus was considered to be the best (below 100μg/ml), an MIC of 125.0μg/ml shown by E.coli, K.pneumoni, P.mirabilis and S.typhi was considered to be better (100-500μg/ml) as such by the action of acetone, ethanol, methanol and hexane extracts on test bacterial spp respectively MIC between (500-1000μg/ml) was considered to be good. The aqueous extracts of Eclipta alba showed good activity against S.pyogenes, B.cereus, E.coli and P.aeruginosa. If the dilution was above 1000μg/ml the extract were considered inactive against S.aureus, K.pneumoniae, P.mirabilis and S.typhi. MBC results were similar to MIC results but in the case of MBC the confirmation was made by absence of growth in culture plates after 24 hrs of incubation at 37ºC. A potent antibacterial and hepatoprotective drug could probably be formulated from the plant extract of Eclipta alba to combat the effects of bacterial and hepatotoxic infections.
ABSTRACT
One hundred thirty parasitologically confirmed cases of kala-azar were randomly divided in two equal treatment groups. Patients in group A were treated by infusion with amphotericin B deoxycholate (ABD), 1 mg/kg day on days 1-20 and the infusion was given in two hours. Patients in group B were treated by an escalating dose of ABD 0.05 mg/kg, 0.1 mg/kg, 0.25 mg/kg, 0.5 mg/kg, 1 mg/kg on days 1-5, respectively and then in the same dosage on alternate days. The infusion was completed in 6 hours. Total dose of 20 mg/kg remaining the same in both the groups, the treatment was completed in 20 days in group A and 43 days in group B. Clinical cure (subsidence of fever, improvement in general well being and regression in the size of the spleen) and parasitological cure (absence of parasites in splenic aspirates at the end of treatment) occurred in all patients in both the groups. Sixty four (99%) patients in each group had not relapsed clinically and parasitologically within 6 months of follow up and were ultimately cured. The two relapsed patients, one in each group were treated with a 20-day course of ABD and were cured. Leukocyte count, haemoglobin, serum albumin increased (P < 0.05) and ESR, spleen and liver size decreased (P < 0.05) at the end of treatment and follow up. Adverse events were similar in both the groups. The minimum cost of treatment estimated was Rs. 14,500 in group B and Rs. 10,000 in Group A. Thus the newer mode of administration was more cost effective. CONCLUSION: It was concluded that newer mode of administration of amphotericin B was as effective and tolerable as the classical mode of administration and was no more toxic. The newer mode of administration of amphotericin B is more cost effective and puts lesser burden on hospital staff and is recommended for use in kala-azar.