A highly sensitive, selective and reproducible chromatographic method is described for determination of low-molecular mass unsaturated aliphatic aldehydes in human serum. The method combines fluorescent labeling using 4-(N,N-Dimethylaminosulfonyl)-7-hydrazino-2,1,3-benzoxadiazole with peroxyoxalate chemiluminescence. The derivatives were separated on a reversed-phase column C8 isocratically using a mixture of acetonitrile and 90 mM imidazole–HNO3 buffer (pH 6.4, 1:1, % v/v). The calibration ranges were: 20–420 nM for methylglyoxal, 16–320 nM for acrolein, 15–360 nM for crotonaldehyde and 20–320 nM for trans-2-hexenal. The detection limits were ranged from 4.4 to 6.5 nM (88–130 fmol/injection), the recovery results were within the range of 87.4–103.8% and the intra and inter-day precision results were lower than 5.5%. The proposed validated method has been successfully applied to healthy, diabetic and rheumatic arthritis patients’ sera with simple pretreatment method. In conclusion, this new method is suitable for routine analysis of large numbers of clinical samples for assessment of the oxidative stress state in patients.

A highly sensitive, selective and reproducible chromatographic method is described for determination of low-molecular mass unsaturated aliphatic aldehydes in human serum. The method combines fluorescent labeling using 4-(N,N-Dimethylaminosulfonyl)-7-hydrazino-2,1,3-benzoxadiazole with peroxyoxalate chemiluminescence. The derivatives were separated on a reversed-phase column C8 isocratically using a mixture of acetonitrile and 90 mM imidazole–HNO3 buffer (pH 6.4, 1:1, % v/v). The calibration ranges were: 20–420 nM for methylglyoxal, 16–320 nM for acrolein, 15–360 nM for crotonaldehyde and 20–320 nM for trans-2-hexenal. The detection limits were ranged from 4.4 to 6.5 nM (88–130 fmol/injection), the recovery results were within the range of 87.4–103.8% and the intra and inter-day precision results were lower than 5.5%. The proposed validated method has been successfully applied to healthy, diabetic and rheumatic arthritis patients’ sera with simple pretreatment method. In conclusion, this new method is suitable for routine analysis of large numbers of clinical samples for assessment of the oxidative stress state in patients.

A highly sensitive, selective and reproducible chromatographic method is described for determination of low-molecular mass unsaturated aliphatic aldehydes in human serum. The method combines fluorescent labeling using 4-(N,N-Dimethylaminosulfonyl)-7-hydrazino-2,1,3-benzoxadiazole with peroxyoxalate chemiluminescence. The derivatives were separated on a reversed-phase column C8 isocratically using a mixture of acetonitrile and 90 mM imidazole–HNO3 buffer (pH 6.4, 1:1, % v/v). The calibration ranges were: 20–420 nM for methylglyoxal, 16–320 nM for acrolein, 15–360 nM for crotonaldehyde and 20–320 nM for trans-2-hexenal. The detection limits were ranged from 4.4 to 6.5 nM (88–130 fmol/injection), the recovery results were within the range of 87.4–103.8% and the intra and inter-day precision results were lower than 5.5%. The proposed validated method has been successfully applied to healthy, diabetic and rheumatic arthritis patients’ sera with simple pretreatment method. In conclusion, this new method is suitable for routine analysis of large numbers of clinical samples for assessment of the oxidative stress state in patients.

4-Hydroxy-2-nonenal (4HNE) is a major aldehyde generated during lipid peroxidation. The clinical monitoring of 4HNE in biological fluids should be useful for the early diagnosis of several diseases involving lipid peroxidation, such as rheumatoid arthritis, Parkinson’s disease and cancer. In this study, an HPLC with fluorescence detection method was developed for the determination of 4HNE in human serum. The proposed method involves the extraction of 4HNE from human serum by sub-zero temperature extraction and fluorescent labeling of 4HNE with 4-(N,N-dimethylaminosulfonyl)-7-hydrazino-2, 1,3-benzoxadiazole. The lower detection limit (signal-to-noise ratio = 3) of the method was 0.06 μM in serum. The proposed method was successfully applied to the measurement of 4HNE in sera obtained from patients with rheumatoid arthritis.

A radical scavenging guided phytochemical study on the leaf of Simmondsia chinensis afforded ten flavonoids (1–10) and four lignans (11–14). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Among isolated compounds, flavonoid aglycones (1–4) showed stronger antioxidant activity than their glycosides (5–10) whilst lignan glycosides (11–14) showed moderate to weak antioxidant activity using DPPH and -carotene methods in relation to BHT (positive control). The inhibitory potential against enzyme lipoxygenase was also evaluated for isolated compounds exhibiting variable potency. For flavonoids, glycosides are less potent inhibitors than free aglycones. Quercetin is the most potent inhibitor with an IC50 of 5.6 µM. Lignoid glycosides exhibited moderate to weak inhibitory effect against lipoxygenase enzyme. Luteolin was used as a positive control in lipoxygenase inhibiting assay.

A radical scavenging guided phytochemical study on the leaf of Simmondsia chinensis afforded ten flavonoids (1–10) and four lignans (11–14). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Among isolated compounds, flavonoid aglycones (1–4) showed stronger antioxidant activity than their glycosides (5–10) whilst lignan glycosides (11–14) showed moderate to weak antioxidant activity using DPPH and -carotene methods in relation to BHT (positive control). The inhibitory potential against enzyme lipoxygenase was also evaluated for isolated compounds exhibiting variable potency. For flavonoids, glycosides are less potent inhibitors than free aglycones. Quercetin is the most potent inhibitor with an IC50 of 5.6 µM. Lignoid glycosides exhibited moderate to weak inhibitory effect against lipoxygenase enzyme. Luteolin was used as a positive control in lipoxygenase inhibiting assay.

A radical scavenging guided phytochemical study on the leaf of Simmondsia chinensis afforded ten flavonoids (1–10) and four lignans (11–14). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Among isolated compounds, flavonoid aglycones (1–4) showed stronger antioxidant activity than their glycosides (5–10) whilst lignan glycosides (11–14) showed moderate to weak antioxidant activity using DPPH and -carotene methods in relation to BHT (positive control). The inhibitory potential against enzyme lipoxygenase was also evaluated for isolated compounds exhibiting variable potency. For flavonoids, glycosides are less potent inhibitors than free aglycones. Quercetin is the most potent inhibitor with an IC50 of 5.6 µM. Lignoid glycosides exhibited moderate to weak inhibitory effect against lipoxygenase enzyme. Luteolin was used as a positive control in lipoxygenase inhibiting assay.

The high mutation rate of RNA viruses has resulted in limitation of vaccine effectiveness and increased emergence of drug-resistant viruses. New effective antivirals are therefore needed to control of the highly mutative RNA viruses. The n-butanol fraction of the stem bark of Mangifera indica exhibited inhibitory activity against influenza neuraminidase (NA) and coxsackie virus 3C protease. Bioassay guided phytochemical study of M. indica stem bark afforded two new compounds including one benzophenone C-glycoside (4) and one xanthone dimer (7), together with eleven known compounds. The structures of these isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Anti-influenza and anti-coxsackie virus activities were evaluated by determining the inhibition of anti-influenza neuraminidase (NA) from pandemic A/RI/5+/1957 H2N2 influenza A virus and inhibition of coxsackie B3 virus 3C protease, respectively. The highest anti-influenza activity was observed for compounds 8 and 9 with IC50 values of 11.9 and 9.2 µM, respectively. Compounds 8 and 9 were even more potent against coxsackie B3 virus 3C protease, with IC50 values of 1.1 and 2.0 µM, respectively. Compounds 8 and 9 showed weak cytotoxic effect against human hepatocellular carcinoma and human epithelial carcinoma cell lines through MTT assay.

The high mutation rate of RNA viruses has resulted in limitation of vaccine effectiveness and increased emergence of drug-resistant viruses. New effective antivirals are therefore needed to control of the highly mutative RNA viruses. The n-butanol fraction of the stem bark of Mangifera indica exhibited inhibitory activity against influenza neuraminidase (NA) and coxsackie virus 3C protease. Bioassay guided phytochemical study of M. indica stem bark afforded two new compounds including one benzophenone C-glycoside (4) and one xanthone dimer (7), together with eleven known compounds. The structures of these isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Anti-influenza and anti-coxsackie virus activities were evaluated by determining the inhibition of anti-influenza neuraminidase (NA) from pandemic A/RI/5+/1957 H2N2 influenza A virus and inhibition of coxsackie B3 virus 3C protease, respectively. The highest anti-influenza activity was observed for compounds 8 and 9 with IC50 values of 11.9 and 9.2 µM, respectively. Compounds 8 and 9 were even more potent against coxsackie B3 virus 3C protease, with IC50 values of 1.1 and 2.0 µM, respectively. Compounds 8 and 9 showed weak cytotoxic effect against human hepatocellular carcinoma and human epithelial carcinoma cell lines through MTT assay.

The high mutation rate of RNA viruses has resulted in limitation of vaccine effectiveness and increased emergence of drug-resistant viruses. New effective antivirals are therefore needed to control of the highly mutative RNA viruses. The n-butanol fraction of the stem bark of Mangifera indica exhibited inhibitory activity against influenza neuraminidase (NA) and coxsackie virus 3C protease. Bioassay guided phytochemical study of M. indica stem bark afforded two new compounds including one benzophenone C-glycoside (4) and one xanthone dimer (7), together with eleven known compounds. The structures of these isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Anti-influenza and anti-coxsackie virus activities were evaluated by determining the inhibition of anti-influenza neuraminidase (NA) from pandemic A/RI/5+/1957 H2N2 influenza A virus and inhibition of coxsackie B3 virus 3C protease, respectively. The highest anti-influenza activity was observed for compounds 8 and 9 with IC50 values of 11.9 and 9.2 µM, respectively. Compounds 8 and 9 were even more potent against coxsackie B3 virus 3C protease, with IC50 values of 1.1 and 2.0 µM, respectively. Compounds 8 and 9 showed weak cytotoxic effect against human hepatocellular carcinoma and human epithelial carcinoma cell lines through MTT assay.