Development and validation of eight cyanogenic glucosides via ultra-high-performance liquid chromatography-tandem mass spectrometry in agri-food

Uncovering Taxiphyllin in bamboo shoots: An analytical perspective

Bamboo shoots, a staple in Asian diets, particularly in India, China, Japan, and Southeast Asia, are valued for their rich nutrients and health benefits. However, they contain cyanogenic glycosides, primarily Taxiphyllin, posing toxicity risks if improperly consumed. This review examines bamboo shoots' nutritional profile, geographical consumption patterns, and the role of Taxiphyllin. It explores the impact of traditional and industrial processing methods, such as boiling, fermentation, and steaming, in reducing Taxiphyllin levels to ensure food safety. Additionally, the paper highlights bamboo shoots' applications in pharmaceuticals, bioethanol production, therapeutics, and cosmetics. Emphasis is placed on the significance of detection technologies in food processing to prevent cyanide poisoning. The findings underscore the need for effective processing and detection techniques to balance bamboo shoots' nutritional and medicinal benefits while mitigating health risks. The review also identifies future research opportunities to maximize their potential in sustainable food and industrial applications.

Flaxseed in Diet: A Comprehensive Look at Pros and Cons

Flaxseeds, which have been consumed for thousands of years, have recently gained increasing popularity due to their rich composition, including omega-3 fatty acids, lignans, proteins, and fibers. These components are strongly associated with various health benefits, such as improving cardiovascular health, preventing certain types of cancer, controlling diabetes, promoting gastro-intestinal well-being, and aiding in weight management. This monograph explores the role of flaxseeds in nutrition, as well as their potential risks. Despite their numerous health benefits, flaxseeds also represent concerns due to excessive consumption and possible contamination, particularly from cyanogenic glycosides. Therefore, the levels of these compounds must be controlled, and this monograph also analyzes the available methods to detect and reduce these contaminants, ensuring the safety of flaxseed and flaxseed products consumers. Flaxseed is considered a valuable addition when incorporated into the diet, but it is necessary to continue research and promote technological improvements to maximize their benefits and minimize their risks.

Novel UHPLC-(+ESI)MS/MS Method for Determining Amygdalin, Prunasin and Total Cyanide in Almond Kernels and Hulls (Prunus dulcis)

Almonds contain cyanogenic glycosides (CNGs), prunasin and amygdalin, which generate hydrogen cyanide upon hydrolysis. Different extraction and analytical methods are currently used to measure CNGs or cyanide (CN), necessitating distinct samples and can lead to inconsistent or incomparable results. To address this, we describe a method that uses ultrasonic-assisted sample extraction. Amygdalin and prunasin are measured directly in the extract, whereas CN is measured in the extract after derivatization with cysteine ethyl ester to form a cyano-S-ethyl-O-cysteine (CNCysEt) conjugate. The amygdalin, prunasin, and CNCysEt are quantified using the same UHPLC-(+ESI)MS/MS method. This new approach measured total CN in ten common almond kernel and hull varieties. The limit of quantitation ranged from 7.78 μg L-1 (amygdalin), 51.36 μg L-1 (prunasin), and 7.80 μg L-1 (CNCysEt; kernel) and 25.02 μg L-1 (CNCysEt; hull). This is the first time CNGs and CN levels are reported for almond hulls. Average total CN levels in hulls (<3 mg kg-1) were significantly lower than levels in kernels (<20 mg kg-1). Based on these findings, the hulls from California sweet almond varieties may be considered for use in human food products without additional processing to reduce CNG levels.

Decelerated skin aging effect of rubber (Hevea brasiliensis) seed oil in cell culture assays

Rubber seeds, the abundant by-products of rubber tree (Hevea brasiliensis), have been studied for sustainable utilization. Nevertheless, there is no information available regarding activity against skin aging. The study aimed to prepare rubber seed oil (RSO) and evaluate fatty acid compositions by gas chromatography - mass spectrometry (GC/MS), linamarin contamination by ultra-high performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS). Additionally, cytotoxicity assay and anti-skin aging activities, including cell proliferating stimulation, cellular antioxidant, collagen stimulation, and matrix metalloproteinase-2 (MMP-2) inhibition, were analyzed in immortalized human skin keratinocytes (HaCaT cells) and human dermal fibroblasts. RSO was pale-yellow oily liquid with an extraction yield of 35.79 ± 0.52%. Principal fatty acids were comprised of oleic (43.37 ± 0.76%), linoleic (38.49 ± 0.81%), palmitic (11.47 ± 0.12%), and stearic (6.66 ± 0.05%) acids. Linamarin contamination was not detected in 100 µg/mL RSO, demonstrating the absence of a cyanogenic glucoside. Non-cytotoxic concentrations of RSO in both cells were in the range of 0.0001-0.1 mg/mL. Activities of RSO against skin aging included the cell proliferating stimulation, the antioxidant activity, the collagen stimulation, and the MMP-2 suppression at mRNA expression level and enzymatic activity. Study results have suggested that rubber seeds can probably be employed as a promising ingredient in the preparations designed for deceleration of skin aging.

Evaluation of exposure to cyanogenic glycosides and potential hydrogen cyanide release in commercially available foods among the Korean population

The release of hydrogen cyanide (HCN) after food ingestion can pose a serious health risk to consumers. This study aimed to simultaneously quantify four cyanogenic glycosides (lotaustralin, prunasin, taxiphyllin, and dhurrin) using liquid chromatography-tandem mass spectrometry. The analysis scope extended beyond agricultural products to various consumer foods to estimate dietary exposure to cyanogenic glycosides and assess its risk levels. The major exposure sources are cassava chips (lotaustralin), apples (seeds) (prunasin and dhurrin), and Prunus mume axis (taxiphyllin). In addition to quantifying specific cyanogenic glycosides, this study proposed the development of a preliminary risk assessment framework based on the dietary exposure assessment and the calculation of theoretical levels of HCN derived from cyanogenic glycoside concentrations. In the absence of established guidelines for the permissible intake of foods containing cyanogenic glycosides, this study provides initial guidance for assessing the risks associated with a range of commonly consumed foods.

Monitoring of cyanogenic compounds behavior during the manufacturing process of sweetened bean paste

To ensure food safety, food business operators must eliminate or reduce hazardous factors in manufacturing processes by implementing effective process controls. Since some beans are known to contain cyanogenic compounds, their distribution and use are permitted only as a raw bean paste material. Therefore, from the perspective of Hazard Analysis and Critical Control Points (HACCP), the purpose of this study is to demonstrate the validity of establishing CCPs and to determine the cyanogenic compounds in intermediate products for effectively managing hazardous substances in the manufacturing process. The previously reported method, post-column HPLC with fluorescence detection, was used for determine cyanogenic compounds in CCPs. While free cyanide ions were only detected at CCP#1, cyanoglycoside analysis was crucial throughout the manufacturing process. Results indicated a decrease in cyanoglycoside concentration as manufacturing progressed, with levels below 10 ppm in the final product. Notably, cyanoglycosides decreased significantly during the shibukiri process (soaking, boiling, and discarding water). The concentration of cyanogenic compounds in raw beans were below the regulated 500 ppm, and the concentrations in the final product were below regulated 10 ppm. In conclusion, it was found that proposed method is very useful for HACCP management to monitor the decrease of cyanide compounds in the manufacturing process.

A Novel UHPLC-MS/MS Based Method for Isomeric Separation and Quantitative Determination of Cyanogenic Glycosides in American Elderberry

LC-MS/MS analyses have been reported as challenging for the reliable separation and quantification of cyanogenic glycosides (CNGs), especially (R)-prunasin and sambunigrin isomers found in American elderberry (Sambucus nigra L. subsp. canadensis (L.) Bolli). Hence, a novel multiple reaction monitoring (MRM)-based ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated in the present study for simultaneous separation and quantification of five CNGs, including amygdalin, dhurrin, linamarin, (R)-prunasin, and (S)-prunasin (commonly referred to as sambunigrin). Initially, the role of ammonium formate was investigated as an aqueous mobile-phase additive in developing MRM-based UHPLC-MS/MS. Later, chromatographic conditions for the resolved separation of (R)-prunasin and sambunigrin were identified. Validation studies confirmed that the developed method has good linearity and acceptable precision and accuracy. A noticeable matrix effect (mainly signal enhancement) was observed in leaf samples only. This method was used to detect and quantify CNGs, including (R)-prunasin and sambunigrin, in leaf and fruit samples of American elderberry. Among the studied CNGs, only (R)-prunasin was detected in the leaf samples. Interestingly, (S)-prunasin (sambunigrin) was not detected in the samples analyzed, even though it has been previously reported in elderberry species.

Catalytic efficiency and thermal stability promotion of the cassava linamarase with multiple mutations for better cyanogenic glycoside degradation

In our previous study, we found that cassava cyanogenic glycosides had an acute health risk. Therefore, to solve this problem, the improvement of specific degradation of cyanogenic glycosides of cassava linamarase during processing is the key. In this study, the catalytic activity and thermal stability of enzymes were screened before investigating the degradation efficiency of cyanogenic glycosides with a cassava linamarase mutant K263P-T53F-S366R-V335C-F339C (CASmut) -controlled technique. The CASmut was obtained with the optimum temperature of 45 °C, which was improved by 10 °C. The specific activity of CASmut was 85.1 ± 4.6 U/mg, which was 2.02 times higher than that of the wild type. Molecular dynamics simulation analysis and flexible docking showed there were more hydrogen bonding interactions at the pocket, and the aliphatic glycoside of the linamarin was partially surrounded by hydrophobic residues. The optimum conditions of degradation reactions was screened with CASmut addition of 47 mg/L at 45 °C, pH 6.0. The CASmut combined with ultrasonication improved the degradation from 478.2 ± 10.4 mg/kg to 86.7 ± 7.4 mg/kg. Those results indicating the great potential of CASmut in applying in the cassava food or cyanogenic food. However, challenges in terms of the catalytic mechanism research is worthy of being noticed in further studies.

Resequencing of global Lotus corniculatus accessions reveals population distribution and genetic loci, associated with cyanogenic glycosides accumulation and growth traits

BACKGROUND

Lotus corniculatus is a widely distributed perennial legume whose great adaptability to different environments and resistance to barrenness make it an excellent forage and ecological restoration plant. However, its molecular genetics and genomic relationships among populations are yet to be uncovered.

RESULT

Here we report on a genomic variation map from worldwide 272 L. corniculatus accessions by genome resequencing. Our analysis suggests that L. corniculatus accessions have high genetic diversity and could be further divided into three subgroups, with the genetic diversity centers were located in Transcaucasia. Several candidate genes and SNP site associated with CNglcs content and growth traits were identified by genome-wide associated study (GWAS). A non-synonymous in LjMTR was responsible for the decreased expression of CNglcs synthesis genes and LjZCD was verified to positively regulate CNglcs synthesis gene CYP79D3. The LjZCB and an SNP in LjZCA promoter were confirmed to be involved in plant growth.

CONCLUSION

This study provided a large number of genomic resources and described genetic relationship and population structure among different accessions. Moreover, we attempt to provide insights into the molecular studies and breeding of CNglcs and growth traits in L. corniculatus.

Analysis of Bitter Almonds and Processed Products Based on HPLC-Fingerprints and Chemometry

In the processing field, there is a saying that "seed drugs be stir-fried". Bitter almond (BA) is a kind of seed Chinese medicine. BA need be used after being fried. To distinguish raw bitter almonds (RBA) from processed products and prove the rationality of "seed drugs be stir-fried", we analyzed the RBA and five processed products (scalded bitter almonds, fried bitter almonds, honey fried bitter almonds, bran fried bitter almonds, bitter almonds cream) using RP-HPLC fingerprints and chemometric methods. The similarity between RBA and processed products was 0.733∼0.995. Hierarchically clustered heatmap was used to evaluate the changes in components. Principal component analysis (PCA) was used for classification, and all samples are distinguished according to RBA and five processing methods. Six chemical markers were obtained by partial least squares discriminant analysis (PLS-DA). The content and degradation rate of amygdalin and β-glucosidase activity were determined. Compared with RBA, the content and degradation rate of amygdalin, and β-glucosidase activity were increased in bitter almonds cream. The content and degradation rate were decreased, and β-glucosidase was inactivated in other processed products. The above results showed that stir-frying had the best effect. The results showed that processing can ensure the stability of RBA quality, and the saying "seed drugs be stir-fried" is reasonable.

Study on the Correlation Between the Appearance Traits and Intrinsic Chemical Quality of Bitter Almonds Based on Fingerprint-Chemometrics

Bitter almond is a well-known and commonly used traditional Chinese medicine (TCM) for relieving coughs and asthma. However, the bioactive chemical composition of bitter almonds, especially their amygdalin content, which determines their quality for TCM use, is variable and this can cause problems with formulating and prescribing TCMs based on bitter almonds. Therefore, a simple method was developed to evaluate the compositional quality of bitter almonds from their appearance traits, based on a combination of chromatographic fingerprinting and chemometrics. Bitter almonds were analyzed by high-performance liquid chromatography (HPLC). Hierarchical cluster analysis (HCA) and principal components analysis (PCA) were applied to classify bitter almonds, which split the samples into two independent clusters. Three chemical markers (amygdalin, prunasin, and one unidentified component) were found by partial least squares-discriminant analysis (PLS-DA). What's more, a new PLS-DA model was reconstructed to confirm the obtained chemical markers from PLS-DA. Additionally, the appearance trait indices and amygdalin content of bitter almond were determined and the classification was confirmed by one-way analysis of variance. This method can easily determine the quality of bitter almonds from their appearance alone, high quality correlated closely with kernels that were larger, oblong in shape and heavier.

Evaluation of the chemical profile from four germplasms sources of Pruni Semen using UHPLC-LTQ-Orbitrap-MS and multivariate analysis

Pruni Semen, the seed of several unique Prunus plants, is a traditional purgative herbal material. To determine the authentic sources of Pruni Semen, 46 samples from four species were collected and analyzed. Ten compounds including multiflorin A (Mul A), a notable purative compound, were isolated and identified by chemical separation and nuclear magnetic resonance spectroscopy. Seventy-six communal components were identified by ultra-high performance liquid chromatography with linear ion trap-quadrupole Orbitrap mass spectrometry, and acetyl flavonoid glycosides were recognized as characteristic constituents. The flavonoids were distributed in the seed coat and cyanogenic glycosides in the kernel. Based on this, methods for identifying Pruni Semen from different sources were established using chemical fingerprinting, quantitative analysis of the eight principal compounds, hierarchical cluster analysis, principal component analysis, and orthogonal partial least squares discriminant analysis. The results showed that the samples were divided into two categories: one is the small seeds from Prunus humilis (Ph) and Prunus japonica (Pj), and the other is the big seeds from Prunus pedunculata (Pp) and Prunus triloba (Pt). The average content of Mul A was 3.02, 6.93, 0.40, and 0.29 mg/g, while the average content of amygdalin was 18.5, 17.7, 31.5, and 30.9 mg/g in Ph, Pj, Pp, and Pt, respectively. All the above information suggests that small seeds might be superior sources of Pruni Semen. This is the first comprehensive report on the identification of chemical components in Pruni Semen from different species.

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Chemical constituents of Pruni semen from four Prunus species were compared.

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Acetyl flavonoid glycosides were identified as the characteristic components.

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Flavonoids were present in the seed coat and cyanogenic glycosides in the kernel.

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The content of acetyl flavonoid in small seeds is significant higher than those in big ones.

Quantitatively analysis and detection of CN- in three food samples by a novel nopinone-based fluorescent probe

Cyanide (CN^-) is one of the most lethal chemical substance and exists in the organisms and environment. Due to the CN^- and CN^--containing chemicals being widely applied in industrial fields and threatening human health, the sensitive and selective detection techniques towards CN^- are still essential. Based on this, a "turn-on" fluorescent probe 2-(4-(5,5-dimethyl-4,5,6,7-tetrahydro-3H-4,6-methanobenzo[d]imidazol-2-yl)styryl)-3-ethylbenzo[d]thiazol-3-ium iodide (NCy) was designed and synthesized for monitoring CN^-. NCy had a distinguishable color change towards CN^- from colorless to yellow under 365 nm UV-light. NCy possessed the merits including low LOD (75 nM), good selectivity, and wide suitable pH range (4-10). The sensing mechanism of NCy towards CN^- was proved by HRMS, ¹H NMR titration and DFT analysis. Furthermore, the probe NCy was successfully utilized in detecting endogenous CN^- in three food samples (green potato, cassava, and bitter almond) quantitatively. In bioimaging aspect, NCy was also successfully applied in detecting the exogenous CN^- in living zebrafish.

A world tour in the name of natural products

BACKGROUND

Names of natural products (NP) are usually given depending on the species of origin, be it a plant, a marine organism or a microbial species. In some cases, names have been given with reference to people, animals, music, foods or places. Many NP refer to countries, cities or specific places such as mountains, deserts, seas and oceans.

PURPOSE

On the basis of NP names, a world tour has been imagined referring to more than one hundred NP with names evocative of over 50 countries and regions.

RESULTS

The world tour goes from UK (britannin) to Italy (vaticanol) in Europe, from Uganda (ugandoside) to Senegal (senegalene, senegalenines) in Africa, from Brazil (brasilin) to Chile (santiaguine) in South America, from Utah (utahin) to Florida (floridanolide) in the US. It includes Central America (mexicanin, panamine) and the Caribbean islands (jamaicin, bahamaolides). It also crosses Alaska (alaskene) and Canada (quebecol, canadaline). The tour continues throughout Asia, from Thailand (thailandine) to China (Chinaldine) and Pakistan (pakistanamine), to finally reaches Oceania with Australia (australigenin) and Vanuatu (vanuatine), among other countries. This virtual journey, without bordure or wall, brings us to the highest mountains (himalayamine), the deepest oceans (pacificins) and the largest deserts (desertomycin).

CONCLUSION

In the current period of COVID-19 pandemia, with restricted opportunities for international travels, this NP name-based virtual journey offers a world tour to learn more from nature and to inspire scientists to contribute to the field of NP discovery and drug design. There are also limitations associated with the use of trivial names for NP. NP names can be further exploited for teaching and learning.

Highly sensitive analysis of cyanogenic glycosides in cold-pressed flaxseed oil by employing cigarette filter fiber-based SPE coupled with ultra-performance liquid chromatography-tandem mass spectrometry

In this study, a highly sensitive method for analysis of 4 cyanogenic glycosides (CNGs) in cold-pressed flaxseed oil was developed by using cigarette filter fiber-based SPE and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The cold-pressed flaxseed oil was diluted with 5% (v/v) isopropanol/n-hexane solution and loaded to a cigarette filters fiber-based SPE column for CNG enrichment and purification. Under optimized conditions, four CNGs could be detected with limits of detection ranging from 1.3 to 4.4 pg/mL. The linear range was 0.05-50 ng/ml with a linear correlation coefficient (r) > 0.9935. CNG recovery ranged from 113% to 133%, and the relative standard deviation was between 0.8% and 20.5%. Finally, the proposed method was applied to the determination of CNGs in nine cold-pressed flaxseed oils.

Overview of Recent Liquid Chromatography Mass Spectrometry-Based Methods for Natural Toxins Detection in Food Products

Natural toxins include a wide range of toxic metabolites also occurring in food and products, thus representing a risk for consumer health. In the last few decades, several robust and sensitive analytical methods able to determine their occurrence in food have been developed. Liquid chromatography mass spectrometry is the most powerful tool for the simultaneous detection of these toxins due to its advantages in terms of sensitivity and selectivity. A comprehensive review on the most relevant papers on methods based on liquid chromatography mass spectrometry for the analysis of mycotoxins, alkaloids, marine toxins, glycoalkaloids, cyanogenic glycosides and furocoumarins in food is reported herein. Specifically, a literature search from 2011 to 2021 was carried out, selecting a total of 96 papers. Different approaches to sample preparation, chromatographic separation and detection mode are discussed. Particular attention is given to the analytical performance characteristics obtained in the validation process and the relevant application to real samples.

Effect of ultrasonic pretreatment on eliminating cyanogenic glycosides and hydrogen cyanide in cassava

Traditional soaking method takes days to remove cassava cyanide. Ten minutes of ultrasonic pretreatment (UPT) was found to be a new effective method to eliminate both cyanogenic glycosides and hydrogen cyanide in cassava. Here, the parameters of UPT were optimized and the underlying mechanisms were investigated. 40.36% and 24.95% of hydrogen cyanide and cyanogenic glycosides in cassava juice were eliminated under 10 min of UPT (45℃, 81 W). UPT before boiling enhanced the total cyanide elimination to 41.94%. The degradation patterns of hydrogen cyanide and cyanogenic glycosides were different. Ultrasound directly eliminated hydrogen cyanide and indirectly degraded cyanogenic glycosides through promoting enzymatic hydrolysis. The β-glucosidase activity was increased by 17.99% induced by ultrasound. This was supported by the movement of hydrophobic residual and the rearrangement of the secondary structure of the molecular as found in fluorescence, CD, FTIR, DSC and TG analysis. This study revealed that UPT acted as a fast and simple technical way in improving cassava safety.

Cyanogenic Derivatives as Chemical Markers for the Authentication of Commercial Products of Bamboo Shoots

The authentication of bamboo shoots found in the marketplace is complex because the chemical profile of processed and unprocessed material is different. During processing, heat derivatives of the potentially toxic cyanogenic glycoside taxiphyllin are produced. Here, we report the isolation and structure elucidation of the two major diarylbutenedinitrile derivatives, which are cis and trans isomers of the rare 2,3-bis(4-hydroxyphenyl)but-2-enedinitrile from a commercial extract of bamboo shoots. These compounds, absent in fresh bamboo shoots, were produced by boiling the shoots of Bambusa vulgaris and were associated with a decrease in levels of taxiphyllin. Furthermore, (E)-2,3-bis(4-hydroxyphenyl)but-2-enedinitrile was quantified in all 16 of the commercial products tested. Its abundance was found to be highly variable, ranging from 1 to 3 mg/g in preserved bamboo shoots and from 10 to 160 mg/mL in commercial aqueous extracts. Of the 15 authenticated bamboo samples tested for taxiphyllin, it was found only in the shoots of B. vulgaris and Gigantochloa verticillata, which represent two edible bamboo species. Our results indicate that diarylbutenedinitriles can be used as markers for the authentication of boil-processed bamboo shoots obtained from taxiphyllin-containing edible species and organs.