Diabetes mellitus, a complex chronic disease that is associated with hyperglycemia (high blood su... more Diabetes mellitus, a complex chronic disease that is associated with hyperglycemia (high blood sugar) affects millions of people worldwide. This study evaluated the hypoglycemic activities of male and female Antidesma bunius, commonly known as currant tree or bignay, extracts in alloxan-treated ICR mice. In addition, the effects of the treatments on blood urea nitrogen (BUN) and creatinine levels were determined. Phytochemical screening using standard protocol was performed. Plant extracts (500 mg/kg) were administered orally via gavage for 14 days and fasting blood glucose (FBG) levels were monitored prior to alloxan-induction on the day of alloxan-induction, and on the 3rd, 7th and 14th days of treatment. Sera were collected on the 14th day to measure the BUN and creatinine levels. Phytochemical screening was performed using standard TLC spray tests. All extracts were found to significantly lower FBG levels compared to the positive (glibenclamide 10 mg/kg) and negative (distilled ...
The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the c... more The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the chiral selector was investigated. The enantioseparation behavior of the analytes with gamma-CD in the absence and presence of different alcohols specifically methanol, ethanol, 2-propanol (IPA), and 2-methyl-2-propanol (TBA), the relationship of enantiomeric resolution (R(s)) values with either hydrophobicity or bulkiness of the alcohols, as well as the effect of these alcohols on interaction of the analytes with gamma-CD were studied. Results showed that hydrophobicity and/or bulkiness of alcohols have an influence on the enantioresolution of most of the analytes based on the relatively high correlation coefficients (R) obtained between R(s) versus log P and between R(s) versus ovality (i.e., parameter to indicate bulkiness of a molecule). Comparison of the values of the average binding constants obtained for each enantiomeric pair in the presence and absence of 5% IPA showed that alcohols can increase, decrease, or give a minimal effect on the analyte-gamma-CD interaction depending on the analyte. Furthermore, the significant enhancement in the enantioresolution of both propranolol and pindolol in the presence of either IPA or TBA led to the baseline enantioresolution of both drugs using 35 mM gamma-CD.
The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the c... more The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the chiral selector was investigated. The enantioseparation behavior of the analytes with gamma-CD in the absence and presence of different alcohols specifically methanol, ethanol, 2-propanol (IPA), and 2-methyl-2-propanol (TBA), the relationship of enantiomeric resolution (R(s)) values with either hydrophobicity or bulkiness of the alcohols, as well as the effect of these alcohols on interaction of the analytes with gamma-CD were studied. Results showed that hydrophobicity and/or bulkiness of alcohols have an influence on the enantioresolution of most of the analytes based on the relatively high correlation coefficients (R) obtained between R(s) versus log P and between R(s) versus ovality (i.e., parameter to indicate bulkiness of a molecule). Comparison of the values of the average binding constants obtained for each enantiomeric pair in the presence and absence of 5% IPA showed that alcohols can increase, decrease, or give a minimal effect on the analyte-gamma-CD interaction depending on the analyte. Furthermore, the significant enhancement in the enantioresolution of both propranolol and pindolol in the presence of either IPA or TBA led to the baseline enantioresolution of both drugs using 35 mM gamma-CD.
Journal of Liquid Chromatography & Related Technologies, 2007
Abstract Separation of seven ginsenosides at elevated temperature by ultra high pressure liquid c... more Abstract Separation of seven ginsenosides at elevated temperature by ultra high pressure liquid chromatography (UHPLC) on reversed phase C18‐bonded silica stationary phase was studied. All separations were carried out with a binary mobile phase consisting of ...
In this work a new method to detect the existence of chiral amino acids in orange juice is presen... more In this work a new method to detect the existence of chiral amino acids in orange juice is presented. The method employs beta-cyclodextrins and micellar electrokinetic chromatography with laser-induced fluorescence (MEKC-LIF) to separate and detect L- and D-amino acids (L-aa and D-aa) previously derivatized with fluorescein isothiocianate (FITC). A systematic optimization of the chiral-MEKC conditions is done bringing about in less than 20 min a good separation of the main amino acids found in orange juice (i.e., Pro, Asp, Ser, Asn, Glu, Ala, Arg, and the nonchiral GABA, i.e., gamma-aminobutyric acid). Using this procedure, the analysis time reproducibility for the 15 standard compounds (L-aa, D-aa, and GABA) has been determined to be better than 0.2% (n = 5) for the same day and better than 0.7% (n = 15) for three different days. Corrected peak area reproducibility is somewhat lower, providing values better than 3.3% (n = 5) for the same day and 6.9% (n = 15) for three different days. The limit of detection using this procedure was determined to be 0.86 attomoles for L-Arg. The optimized FITC derivatization method allows the easy and straightforward detection of amino acids in orange concentrates and juices (i.e., only centrifugation of diluted samples for 5 min is needed prior to their derivatization). D-Ala, D-Asp, D-Arg, and D-Glu were determined in orange juices and orange concentrates from different geographical origins using this new method. Moreover, the effect of different temperature treatments (50, 92, and 150 degrees C) on the content of D-aa in orange juice was evaluated.
Page 1. Chromatographic Behavior of Uric Acid and Methyl Uric Acids on a Diol Column in HILIC Noe... more Page 1. Chromatographic Behavior of Uric Acid and Methyl Uric Acids on a Diol Column in HILIC Noel S. Quiming1,2, Nerissa L. Denola1,3, Yoshihiro Saito1, AliciaP. Catabay4, Kiyokatsu Jinno1,& 1 School of Materials Science ...
Diabetes mellitus, a complex chronic disease that is associated with hyperglycemia (high blood su... more Diabetes mellitus, a complex chronic disease that is associated with hyperglycemia (high blood sugar) affects millions of people worldwide. This study evaluated the hypoglycemic activities of male and female Antidesma bunius, commonly known as currant tree or bignay, extracts in alloxan-treated ICR mice. In addition, the effects of the treatments on blood urea nitrogen (BUN) and creatinine levels were determined. Phytochemical screening using standard protocol was performed. Plant extracts (500 mg/kg) were administered orally via gavage for 14 days and fasting blood glucose (FBG) levels were monitored prior to alloxan-induction on the day of alloxan-induction, and on the 3rd, 7th and 14th days of treatment. Sera were collected on the 14th day to measure the BUN and creatinine levels. Phytochemical screening was performed using standard TLC spray tests. All extracts were found to significantly lower FBG levels compared to the positive (glibenclamide 10 mg/kg) and negative (distilled ...
The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the c... more The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the chiral selector was investigated. The enantioseparation behavior of the analytes with gamma-CD in the absence and presence of different alcohols specifically methanol, ethanol, 2-propanol (IPA), and 2-methyl-2-propanol (TBA), the relationship of enantiomeric resolution (R(s)) values with either hydrophobicity or bulkiness of the alcohols, as well as the effect of these alcohols on interaction of the analytes with gamma-CD were studied. Results showed that hydrophobicity and/or bulkiness of alcohols have an influence on the enantioresolution of most of the analytes based on the relatively high correlation coefficients (R) obtained between R(s) versus log P and between R(s) versus ovality (i.e., parameter to indicate bulkiness of a molecule). Comparison of the values of the average binding constants obtained for each enantiomeric pair in the presence and absence of 5% IPA showed that alcohols can increase, decrease, or give a minimal effect on the analyte-gamma-CD interaction depending on the analyte. Furthermore, the significant enhancement in the enantioresolution of both propranolol and pindolol in the presence of either IPA or TBA led to the baseline enantioresolution of both drugs using 35 mM gamma-CD.
The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the c... more The effects of alcohol on the CE enantioseparation of selected basic drugs with gamma-CD as the chiral selector was investigated. The enantioseparation behavior of the analytes with gamma-CD in the absence and presence of different alcohols specifically methanol, ethanol, 2-propanol (IPA), and 2-methyl-2-propanol (TBA), the relationship of enantiomeric resolution (R(s)) values with either hydrophobicity or bulkiness of the alcohols, as well as the effect of these alcohols on interaction of the analytes with gamma-CD were studied. Results showed that hydrophobicity and/or bulkiness of alcohols have an influence on the enantioresolution of most of the analytes based on the relatively high correlation coefficients (R) obtained between R(s) versus log P and between R(s) versus ovality (i.e., parameter to indicate bulkiness of a molecule). Comparison of the values of the average binding constants obtained for each enantiomeric pair in the presence and absence of 5% IPA showed that alcohols can increase, decrease, or give a minimal effect on the analyte-gamma-CD interaction depending on the analyte. Furthermore, the significant enhancement in the enantioresolution of both propranolol and pindolol in the presence of either IPA or TBA led to the baseline enantioresolution of both drugs using 35 mM gamma-CD.
Journal of Liquid Chromatography & Related Technologies, 2007
Abstract Separation of seven ginsenosides at elevated temperature by ultra high pressure liquid c... more Abstract Separation of seven ginsenosides at elevated temperature by ultra high pressure liquid chromatography (UHPLC) on reversed phase C18‐bonded silica stationary phase was studied. All separations were carried out with a binary mobile phase consisting of ...
In this work a new method to detect the existence of chiral amino acids in orange juice is presen... more In this work a new method to detect the existence of chiral amino acids in orange juice is presented. The method employs beta-cyclodextrins and micellar electrokinetic chromatography with laser-induced fluorescence (MEKC-LIF) to separate and detect L- and D-amino acids (L-aa and D-aa) previously derivatized with fluorescein isothiocianate (FITC). A systematic optimization of the chiral-MEKC conditions is done bringing about in less than 20 min a good separation of the main amino acids found in orange juice (i.e., Pro, Asp, Ser, Asn, Glu, Ala, Arg, and the nonchiral GABA, i.e., gamma-aminobutyric acid). Using this procedure, the analysis time reproducibility for the 15 standard compounds (L-aa, D-aa, and GABA) has been determined to be better than 0.2% (n = 5) for the same day and better than 0.7% (n = 15) for three different days. Corrected peak area reproducibility is somewhat lower, providing values better than 3.3% (n = 5) for the same day and 6.9% (n = 15) for three different days. The limit of detection using this procedure was determined to be 0.86 attomoles for L-Arg. The optimized FITC derivatization method allows the easy and straightforward detection of amino acids in orange concentrates and juices (i.e., only centrifugation of diluted samples for 5 min is needed prior to their derivatization). D-Ala, D-Asp, D-Arg, and D-Glu were determined in orange juices and orange concentrates from different geographical origins using this new method. Moreover, the effect of different temperature treatments (50, 92, and 150 degrees C) on the content of D-aa in orange juice was evaluated.
Page 1. Chromatographic Behavior of Uric Acid and Methyl Uric Acids on a Diol Column in HILIC Noe... more Page 1. Chromatographic Behavior of Uric Acid and Methyl Uric Acids on a Diol Column in HILIC Noel S. Quiming1,2, Nerissa L. Denola1,3, Yoshihiro Saito1, AliciaP. Catabay4, Kiyokatsu Jinno1,& 1 School of Materials Science ...
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