The aim of this study was to characterize the polyphenolic composition by determination of chemical fingerprints of Methanolic extracts of Ocimum canum Sims, Ocimum basilicum L. and Ocimum gratissimum L. from Democrat...The aim of this study was to characterize the polyphenolic composition by determination of chemical fingerprints of Methanolic extracts of Ocimum canum Sims, Ocimum basilicum L. and Ocimum gratissimum L. from Democratic Republic of Congo and to compare their antisickling activity of that of rosmarinic acid, the major compound to those of methanolic extracts. Phytochemical analysis performed by TLC and HPLC analysis, showed that rosmarinic acid is the most abundant phenolic acid in these Ocimum species according to the following order O. basilicum L., O. gratissimum L. and O. canum Sims. Methanolic extracts of these three species and pure rosmarinic acid showed significant antisickling activities with minimal concentration of normalization values of 0.18 ± 0.03, 0.23 ± 0.04, 0.26 ± 0.04 and 0.31 ± 0.05 mg/mL for rosmarinic acid, O. basilicum L., O. gratissimum L. and O. canum Sims methanolic extracts respectively. The antisickling activity order is the same as that of the rosmarinic acid content, indicating that this polyphenolic acid would be among the main active molecules in these extracts.展开更多
To detect urea content in milk powder, a nonlinear chemical fingerprint technique was developed. In our study, Belousov-Zhabotinsky oscillatory chemical reaction (B-Z) was performed using milk powder and malonic acid ...To detect urea content in milk powder, a nonlinear chemical fingerprint technique was developed. In our study, Belousov-Zhabotinsky oscillatory chemical reaction (B-Z) was performed using milk powder and malonic acid as main dissipative substances. The same dosage of milk powder with or without artificially added urea was introduced to “H+ + Ce4+ + + malonic acid” oscillating system, respectively, and nonlinear chemical fingerprints of different milk powder were thus obtained. The proposed method was based on a linear relationship between inductive time of non-linear chemical fingerprints and urea content in milk powder, which held when urea content in milk powder was in the range of 0 - 40 mg/g. A detection limit of 7.8 × 10<sup>-3</sup>mg/g was also obtained. Our results showed that the method could be used to certify urea content in milk powder without pretreatment of samples, which was more simple and economical compared with traditional methods.展开更多
Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of th...Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of the compounds by standard chromatographic techniques.With the help of DART-MS,chemical fingerprint of raw plant parts were generated,which revealed the presence of piperidine alkaloids in leaf,pod and flower.A comparative study of the distribution pattern,showed variation in the presence and distribution of these alkaloids in various parts of P.juliflora.The leaves and pod displayed the largest alkaloid pattern with a total of 12 different alkaloids in each part,whereas only 4 alkaloids were present in flower.Alkaloids:julifloridine,prosopine,prosopinine and prosafrinine were ubiquitously distributed in all the alkaloid rich plant parts.Juliprosopine was pre-eminet alkaloid in leaf,whereas pod and flower displayed copious amounts of julifloridine.展开更多
文摘The aim of this study was to characterize the polyphenolic composition by determination of chemical fingerprints of Methanolic extracts of Ocimum canum Sims, Ocimum basilicum L. and Ocimum gratissimum L. from Democratic Republic of Congo and to compare their antisickling activity of that of rosmarinic acid, the major compound to those of methanolic extracts. Phytochemical analysis performed by TLC and HPLC analysis, showed that rosmarinic acid is the most abundant phenolic acid in these Ocimum species according to the following order O. basilicum L., O. gratissimum L. and O. canum Sims. Methanolic extracts of these three species and pure rosmarinic acid showed significant antisickling activities with minimal concentration of normalization values of 0.18 ± 0.03, 0.23 ± 0.04, 0.26 ± 0.04 and 0.31 ± 0.05 mg/mL for rosmarinic acid, O. basilicum L., O. gratissimum L. and O. canum Sims methanolic extracts respectively. The antisickling activity order is the same as that of the rosmarinic acid content, indicating that this polyphenolic acid would be among the main active molecules in these extracts.
文摘To detect urea content in milk powder, a nonlinear chemical fingerprint technique was developed. In our study, Belousov-Zhabotinsky oscillatory chemical reaction (B-Z) was performed using milk powder and malonic acid as main dissipative substances. The same dosage of milk powder with or without artificially added urea was introduced to “H+ + Ce4+ + + malonic acid” oscillating system, respectively, and nonlinear chemical fingerprints of different milk powder were thus obtained. The proposed method was based on a linear relationship between inductive time of non-linear chemical fingerprints and urea content in milk powder, which held when urea content in milk powder was in the range of 0 - 40 mg/g. A detection limit of 7.8 × 10<sup>-3</sup>mg/g was also obtained. Our results showed that the method could be used to certify urea content in milk powder without pretreatment of samples, which was more simple and economical compared with traditional methods.
文摘Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of the compounds by standard chromatographic techniques.With the help of DART-MS,chemical fingerprint of raw plant parts were generated,which revealed the presence of piperidine alkaloids in leaf,pod and flower.A comparative study of the distribution pattern,showed variation in the presence and distribution of these alkaloids in various parts of P.juliflora.The leaves and pod displayed the largest alkaloid pattern with a total of 12 different alkaloids in each part,whereas only 4 alkaloids were present in flower.Alkaloids:julifloridine,prosopine,prosopinine and prosafrinine were ubiquitously distributed in all the alkaloid rich plant parts.Juliprosopine was pre-eminet alkaloid in leaf,whereas pod and flower displayed copious amounts of julifloridine.