Determination of sibutramine adulterated in herbal slimming product using thin layer chromatography (TLC) densitometric method with TLC silica gel 60 F 254 aluminium plate as stationary phase and mixture of toluen-diethylamine (10:0.3) as mobile phase has been developed. The calibration curve in the concentration range of 0.50 to 5.00µg/spot showed good linier relationship (r 2 = 0.9986). The limit of detection and quantitation (LOD and LOQ) were 217.5ng and 724.9ng/spot, respectively. The method gave satisfactory specificity, linierity, precision and accuracy validation criteria and was applied for determination of sibutramine in herbal slimming products obtained from several drugstrores in Depok City, West Java, Indonesia. Results of the determination showed that six of seven samples analyzed were detected containing sibutramine HCl w ith the concentration of 2.45-26.24mg in a single dosage of slimming herbal products.
Objective: To determine tamoxifen (TAM) and its metabolites, endoxifen (END) and 4-hydroxytamoxifen (4-HT) in patients' DBS simultaneously for monitoring studies purposes. Methods: The UPLC-MS/MS method was developed and validated with clomiphene as the internal standard. Optimization was done by evaluating several parameters that affect the efficiency of DBS preparation and analysis of TAM and its metabolites. Results: Sample preparation was performed by protein precipitation using methanol. The separation was performed on UPLC Class BEH C18 using formic acid 0.1%-formic acid 0.1% in acetonitrile (35:65) as the mobile phase in isocratic mode at 0.25 ml/minute. The mass detection was performed on Waters Xevo TQD using ESI+for TAM, END, 4-HT, and clomiphene as internal standard with m/z value: 372.2>72.27; 374.29>58.2; 388.29>72.19; dan 406.28>100.17 respectively. This method was linear within the range of 5-200 ng/ml for TAM; 1-40 ng/ml for END; and 0.5-20 ng/ml for 4-HT with r value of ≥0.9983; ≥0.9964; and ≥0.9981. %diff and %CV of the assay were within 15% and within 20% for LLOQ. The method was applied to 29 breast cancer patients, where the results lied between 30.29 and 188.63 ng/ml for tamoxifen, 1.45 and 28.77 ng/ml for endoxifen, 0.21 and 11.28 ng/ml for 4-hydroxytamoxifen. Conclusion: This method has successfully fulfilled validation requirement referring to 2011 EMA and 2013 FDA guidelines. The method was successfully applied to determine TAM, END, and 4-HT in DBS of breast cancer ER+patients. TAM and its metabolites level in patients were showed high variability with END concentration of 2 patients below the clinical threshold.
Objective: The purpose of this research was to investigate the potential of yeast-producing bioethanol from few type of grapes and durians. Methods:The isolation of potential yeast was carried out from five different types of fruits, namely, red grape, black grape, durian Medan, durian Bangkok, and durian Monthong. Optimum fermentation condition was obtained by comparing shaking and non-shaking, detoxifying the hydrolysate, varying temperature, and concentration of N source in the culture medium. Results:The results of an analysis using gas chromatography showed that the ideal conditions for the fermentation of bioethanol were at a temperature below room temperature (+220°C), without shaking, using the hydrolysate, without detoxification, and with a 1% concentration of ammonium acetate as a source of N. Among the isolates, isolate DM1 obtained from durian Medan showed a strong potential to produce bioethanol but at lower levels than Saccharomyces cerevisiae. The concentration of ethanol produced was 0.241%. Conclusion:A yeast isolate with a strong potential to produce bioethanol was discovered as the DM1, which isolated from Medanese durian. The isolate produced 0.241% bioethanol. However, fermentation optimization efforts using an oil palm empty fruit bunch hydrolysate substrate did not yield higher concentrations.
Objective: Tamoxifen (TAM) is a hormonal therapy that is clinically proven to reduce breast cancer recurrence by blocking estrogen receptor, mainly through its active metabolites, 4-hydroxytamoxifen (4HT) and endoxifen (END), which have a higher affinity to ER than TAM itself. The objective of the present study was to develop and validate simple and rapid LC-MS/MS method for analysis TAM and its metabolites simultaneously in dried blood spot (DBS) sample for monitoring studies purposes. Methods: Optimization was done by evaluating several parameters that affect the efficiency of DBS preparation, such as blood spot volume, drying time and extraction method from the DBS paper. The effectiveness of chromatographic conditions was also optimized by varying flow rate, mobile phase combination and gradient. Clomiphene was used as the internal standard. Results: The result showed that preparation of 20 µl blood spot volume with 120 min of drying time and 25 min of extraction time using 1 ml methanol was the most efficient condition and also fulfilled recovery and matrix effect requirement according to FDA and EMA guidelines. The separation was performed on UPLC Class BEH C18 using formic acid 0.1%-formic acid 0.1% in acetonitrile (35:65) as the mobile phase in isocratic mode at 0.25 ml/min with a total analysis time of 4 min. Conclusion: This method has successfully fulfilled all validation requirements referring to EMA and FDA guidelines.
Objective: To further understand this compound, we synthesized and evaluated the antioxidant and anti-inflammatory activity of a series of itsMannich base derivatives.Methods: We synthesized the compounds via the previously reported Mannich reaction method. Their structures were elucidated by Fouriertransforminfrared,1H-NMR,13C-NMR, and high-resolution mass spectra. The derivatives’ anti-inflammatory and antioxidant activities were testedusing the inhibition of protein denaturation method and the 2,2-diphenyl-2-picrylhydrazyl free radical scavenging assay.Results: The IC50 values for the anti-inflammatory activity of the 2,6-dimethylmorpholine, pyrrolidine, 1-methylpiperazine, and dimethylamineMannich base derivatives 2a–d were 10.67, 10.72, 37.75, and 1.93 μM, respectively; for (2E,6E)-2-({4-hydroxy-3-methoxyphenyl}methylidene)-6-(phenylmethylidene)cyclohexan-1-one (1), diclofenac sodium, and curcumin, the IC50 values were 56.29, 1.52, and 8.43 μM, respectively. The IC50values for the antioxidant activity of compounds 2a–2d were 229.62, 57.29, 280.43, and 219.22 μM, respectively; for compound 1, quercetin, andcurcumin, the IC50 values were 144.22, 27.28, and 26.45 μM, respectively.Conclusion: Substituting Mannich bases into (2E,6E)-2-[(4-hydroxy-3-methoxyphenyl) methylidene]-6-(phenylmethylidene)cyclohexan-1-oneenhanced its anti-inflammatory activity, but lowered its antioxidant activity. Compound 2d, (2E,6E)-2-({3-[(dimethylamino)methyl]-4-hydroxy-5-methoxyphenyl}methylidene)-6-(phenyl methylidene)cyclohexan-1-one, exhibited potent anti-inflammatory activity comparable to diclofenacsodium and four times higher than curcumin. However, further investigation of this compound’s mechanism of action and toxicity is warranted.
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