Characterisation and in vitro cytotoxicity of toxic and degradation compounds in bamboo shoots (Dendrocalamus Sinicus) during traditional fermentation

Fermentation has been historically applied to reduce bamboo shoot (BS) toxicity. However, the underlying degradation pathway of the toxic compounds remains unknown. In this work, the cytotoxicity of BS against the BRL-3A cells was evaluated, and the changes in chemical constituents were determined to reveal the influence of fermentation on BS. The in vitro toxic evaluation revealed fermentation time was crucial in decreasing the toxicity. The main compounds in fresh and fermented were qualitatively and quantitatively determined and were further targeted isolated and identified. A mathematical model to describe the change rate as a function of fermentation time was formulated. Dynamic profiling revealed that taxiphyllin 1 , p-hydroxybenzaldehyde 2 and methyl-p-hydroxybenzoate 3 decreased and transformed into intermediate compounds (p-hydroxybenzoic acid 4 and p-hydroxybenzyl alcohol 5 ), finally converting into p-hydroxytoluene 6 during fermentation. The results provided basis on the chemical components for practical fermentation and the quality control of BS products.     

Uncovering a challenging case of adulterated commercial saffron

The analytical approach presented uncovers the type of adulteration of a commercial product labeled as “saffron”, sold packed in powder form in a major consuming country. Simple colorimetric and spectrometric tests included in the ISO 3632 trade standard indicated only that it was not “pure saffron”. The TLC and HPLC methods recommended in the same standard for the detection of artificial colorants were not applicable due to limited sample amount available. Since it could not be precluded that substances other than artificial colorants have been used, deeper investigation through metabolic fingerprinting was necessary to uncover chemical composition of the sample. The multistep workflow that exploited chromatographic (HPLC) and spectroscopic (UV–Vis, mid-infrared (FT-IR), and nuclear magnetic resonance (NMR)) data from in-house databases uncovered a “tailor-made” case of 100% substitution of saffron by a mixture of exogenous chemical compounds in such a way that the commercial product would approximately mimic not only the appearance of saffron but also its UV–Vis spectrum and specific absorbance values. The findings indicated a sophisticated practice, including total substitution of saffron constituents by tartrazine and sunset yellow along with propane-1,2-diol, propan-2-ol and acylglycerols, probably as emulsifier agents. Interestingly, the perpetrators avoided the use of toxic compounds. To our knowledge such a type of fraud has not been elucidated so far.     

RP-HPLC-DAD法初步考察5种化合物对照品的稳定性

采用RP-HPLC-DAD法同时测定5种常见的性质不稳定的化合物阿魏酸、正丁基苯酞、正丁烯基苯酞、Z-藁本内酯以及亚油酸的对照品,考察其甲醇混合溶液在12 h及4 d内的稳定性。结果表明,5种对照品混合物的甲醇溶液于2 d内稳定性较好,不需新鲜配制,超过56 h则需新鲜配制。