Quantitation of capsaicinoids in different chilies from Austria by a novel UHPLC method

Determination of capsaicin at trace levels in different food, biological and environmental samples by quadruple isotope dilution-gas chromatography mass spectrometry after its preconcentration

Despite the therapeutic properties of capsaicin for some diseases, it shows some side effects for human health. The goal of this study was to develop a precise and accurate analytical strategy for the trace determination of capsaicin in different food, biological and environmental samples including pepper, saliva and wastewater by gas chromatography-mass spectrometry (GC-MS) after spraying-based fine droplet formation-liquid phase microextraction (SFDF-LPME) and quadruple isotope dilution (ID4) method. Acetic anhydride was used as derivatizing agent, and the extraction method was used to enrich the analyte derivative to reach low detection limits. Under the optimum conditions, limit of detection (LOD) and limit of quantitation (LOQ) were determined to be 0.33 and 1.10 µg/kg, respectively. Percent recoveries calculated for SFDF-LPME-GC-MS method ranged between 84.1 and 131.7 %. After the application of ID4-SFDF-LPME-GC-MS method, percent recoveries were obtained in the range of 94.9 and 104.0 % (%RSD ≤ 2.8) for the selected samples. It is obvious that the isotope dilution-based method provided high accurate and precise results due to the elimination of errors during the derivatization, extraction and measurement steps.

Capsaicinoids in Food: An Update on Pretreatment and Analysis Methods since 2010

Capsaicinoids, whose basic chemical structure is the vanilla amide of n-nonanoic acid, are responsible for chili pepper fruits' spicy flavor (pungency) and multiple pharmacological actions. Capsaicinoids are widely used to produce intense flavor food additives due to their sensory attributes of pungency, aroma, and color. To ensure strict quality control for capsaicinoids and maximize their positive effects, valid and sensitive pretreatment and determination methods are urgently needed. Consequently, this review provides a comprehensive summary of capsaicinoids' preparation and analytical technologies in food samples. Pretreatment techniques mainly include liquid-liquid extraction, solid-phase extraction, solid-phase microextraction, and dispersive solid-phase microextraction, among others. Detection methods include liquid chromatography coupled with different detectors, gas chromatography, electrochemical sensor methods, capillary electrophoresis, etc. Furthermore, the advantages and disadvantages of various pretreatment and analytical methods are compared and discussed. Thus, the present paper has attempted to shed light on novel and traditionalpretreatment methods and determination approaches and provided proper comments about their new developments and applications.

Unleashing the bioactive potential of Capsicum chinense cv Bhut Jolokia: a comparison of microwave- and ultrasound-mediated extraction techniques for lipophilic capsaicin

This study investigated the extraction of capsaicin from Capsicum chinense cv Bhut Jolokia using rice bran oil (RBO) as a 'green solvent' via microwave- and ultrasound-mediated techniques (MME and UME) as an alternative to hazardous organic solvents. Extraction conditions were optimised using MME at 180 and 300 W for 2 and 8 min and UME at 300 and 400 W for 10 and 30 min. The maximum capsaicin yield obtained was 12.47 mg/mL, with a corresponding gamma oryzanol content of 8.46 mg/mL. The peroxide value of the extract (capsaicin-infused RBO) was found to be within permissible limits as per Codex Alimentarius specifications. Results strongly suggest the potential of RBO as a novel solvent for extraction of capsaicin. The capsaicin-enriched oil can be used as a functional food ingredient due to its health-promoting properties.

Application of a reversed-phase ionic liquid dispersive liquid-liquid microextraction method for the extraction and preconcentration of domoic acid from urine samples

A simple and efficient sample extraction and preconcentration method based on reversed-phase ionic liquid dispersive liquid-liquid microextraction (RP-IL-DLLME) had been developed and used to quantify the domoic acid in human urine samples. The analysis was performed by ultra-performance liquid chromatography and photodiode array detection. During the procedure, hydrophilic ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate [C₄mim] BF₄ as dispersive solvent and NaOH solution was chosen as extraction solvent. Some important parameters in the method were investigated to get high enrichment factors. Under optimal conditions, the linearity of the method was in the range of 0.1–10 ng mL⁻¹ and the correlation coefficient was above 0.9996. The relative standard deviations (RSDs) of the developed methods for intra-day (n = 5) and inter-day (n = 5) precision ranged from 1.9 to 3.9%. Meanwhile, limit of detection (LOD) was 0.03 ng mL⁻¹(S/N = 3) and that of quantification (LOQ) was 0.1 ng mL⁻¹(S/N = 10) with the enrichment factors (EF) being 230. Eventually, the proposed method was successfully applied to the determination of Dominic acid in human urine samples.

Non-destructive prediction of the hotness of fresh pepper with a single scan using portable near infrared spectroscopy and a variable selection strategy

There has been no study on using near-infrared spectroscopy (NIRS) to predict the hotness of fresh pepper. This study is aimed at developing a non-destructive and accurate method for determining the hotness of fresh peppers using portable NIRS and the variable selection strategy. Spectra from different locations on samples were obtained non-destructively with a single scan. Quantitative models were established using partial least squares (PLS) with a variable selection method or fusion method. The results showed that near-stalk was the best spectral acquisition location for quantitative analysis. The variable selection strategy allows the selection of targeted characteristic variables and improves the results. A fusion method, namely variable adaptive boosting partial least squares (VABPLS), was selected for optimal prediction of the performance. In the optimized model, the root mean square errors of prediction for the validation set (RMSEPvs) of capsaicin, dihydrocapsaicin and pungency degree were 0.295, 0.143 and 47.770, respectively, while the root mean square errors of prediction for the prediction set (RMSEPps) collected one month later were 0.273, 0.346 and 75.524, respectively.

A sensitive 1 H NMR spectroscopic method for the quantification of capsaicin and capsaicinoid: morpho-chemical characterisation of chili land races from northeast India

INTRODUCTION

Proton (¹ H) nuclear magnetic resonance (NMR) spectroscopy based analytical method for the quantification of capsaicin (major pungent principle of chili) has certain advantages including short data acquisition time and better structural authentication. Earlier NMR methods are associated with either of the bottlenecks such as low or lack of information on the sensitivity and scope for the quantification of total capsaicinoid.

OBJECTIVE

To develop a sensitive ¹ H quantitative NMR (qNMR) technique for capsaicin and total capsaicinoid in dry chili and chili oleoresin and to demonstrate its applicability in a real sample set.

METHOD

A ¹ H qNMR method was developed using benzene as the internal standard for the quantification of capsaicin (terminal methyl signal) as well as total capsaicinoid (benzyl methylene signal) in dry chili and oleoresin and validated in terms of specificity, linearity, sensitivity, accuracy and precision.

RESULTS

The developed ¹ H qNMR method was specific, sensitive (limit of detection 4.4 μg/mL and limit of quantitation 14.8 μg/mL), linear in the range 0.083-8.33 mg/mL of capsaicin, accurate and precise. The credibility of the developed method was showcased in the morpho-chemical characterisation of commercially available 15 chili land races from northeast India. The analysis identified the land races with a wide range of capsaicin (trace to 1.49% in the dry fruit and trace to 6.21% in the oleoresin w/w) and oleoresin content (3.35-26.78% w/w).

CONCLUSION

The standardized ¹ H qNMR method facilitated the findings of chemical basis for the selection of chili land races from this region, capable of producing high-yielding oleoresin with intended degree of pungency.

Schisandra chinensis bee pollen's chemical profiles and protective effect against H2O2-induced apoptosis in H9c2 cardiomyocytes

Background

Schisandra chinensis (Turcz.) Baill bee pollen extract (SCBPE) is often used as a functional food in China due to its good antioxidant property. However, its chemical compositions and effects on H9c2 cardiomyocytes against H₂O₂-induced cell injury still lacks of reports thus far. This study aimed to characterize the main components of SCBPE and investigate its protective effects against H₂O₂-induced H9c2 cardiomyocyte injury.

Methods

The main components of SCBPE were analyzed via ultraperformance liquid chromatography–quadrupole time-of-flight tandem mass spectrometry (UPLC–QTOF MS/MS). The three main nucleosides in SCBPE were quantitatively analyzed via ultraperformance liquid chromatography–diode array detection. Furthermore, the potential mechanism by which SCBPE exerts protective effects against H₂O₂-induced H9c2 cardiomyocyte injury was explored for the first time via cell survival rate measurements; cell morphological observation; myocardial superoxide dismutase (SOD) activity and malondialdehyde (MDA) and glutathione (GSH) level determination; flow cytometry; and quantitative polymerase chain reaction.

Results

Two carbohydrates, three nucleosides, and nine quinic acid nitrogen-containing derivatives in SCBPE were identified or tentatively characterized via UPLC–QTOF MS/MS. The nine quinic acid nitrogen-containing derivatives were first reported in bee pollen. The contents of uridine, guanosine, and adenosine were 2.4945 ± 0.0185, 0.1896 ± 0.0049, and 1.8418 ± 0.0157 μg/mg, respectively. Results of in vitro experiments showed that cell survival rate, myocardial SOD activity, and GSH level significantly increased and myocardial MDA level significantly decreased in SCBPE groups compared with those in H₂O₂ group. Cell morphology in SCBPE groups also markedly improved compared with that in H₂O₂ group. Results indicated that SCBPE protected H9c2 cardiomyocytes from H₂O₂-induced apoptosis by downregulating the mRNA expressions of Bax, cytochrome C, and caspase-3 and upregulating the Bcl-2 mRNA expression.

Conclusions

This study is the first to report that SCBPE could protect against oxidative stress injury and apoptosis in H₂O₂-injured H9c2 cells. Results indicated that the nucleosides and quinic acid nitrogen-containing derivatives could be the main substances that exert protective effects against H₂O₂-induced H9c2 cardiomyocyte injury.

Liquid Chromatography Analysis of Common Nutritional Components, in Feed and Food

Food and feed laboratories share several similarities when facing the implementation of liquid-chromatographic analysis. Using the experience acquired over the years, through application chemistry in food and feed research, selected analytes of relevance for both areas were discussed. This review focused on the common obstacles and peculiarities that each analyte offers (during the sample treatment or the chromatographic separation) throughout the implementation of said methods. A brief description of the techniques which we considered to be more pertinent, commonly used to assay such analytes is provided, including approaches using commonly available detectors (especially in starter labs) as well as mass detection. This manuscript consists of three sections: feed analysis (as the start of the food chain); food destined for human consumption determinations (the end of the food chain); and finally, assays shared by either matrices or laboratories. Analytes discussed consist of both those considered undesirable substances, contaminants, additives, and those related to nutritional quality. Our review is comprised of the examination of polyphenols, capsaicinoids, theobromine and caffeine, cholesterol, mycotoxins, antibiotics, amino acids, triphenylmethane dyes, nitrates/nitrites, ethanol soluble carbohydrates/sugars, organic acids, carotenoids, hydro and liposoluble vitamins. All analytes are currently assayed in our laboratories.

The genusCapsicum: a phytochemical review of bioactive secondary metabolites

The Capsicum genus is one of the most popular plants consumed and cultivated worldwide, containing approximately 50 000 varieties of pepper. Due to its wide biodiversity, the chemical composition within the genus also presents a great variability. Its major applications are in food and pharmacological industry, as pepper presents a chemical composition rich in capsaicinoids, carotenoids, flavonoids and volatile compounds which is attributed to the ability of the fruit to remove insipidity, produce aromas and act against oxidative diseases. Due the existence of several cultivars there is a huge intraspecific chemical variability within each species, which can be considered as an obstacle when selecting and cultivating a species to be applied as a natural product source for a specific objective. The usage of pepper-based products in different industrial areas requires pre-established ranges of chemical compounds, such as capsaicinoids, which in high concentration are toxic when consumed by humans. Applying a pepper with a chemical profile closely related to the concentration that is required after industrial processing can improve efficacy and effectiveness of the process. An insight into the chemical characteristics of major secondary bioactive compounds within Capsicum, the factors that affect their concentration and their chemosystematic implication are reported and discussed.

The Capsicum genus is economically important due to its chemical profile which is rich in capsaicinoids, carotenoids and flavonoids. Its unique chemical composition allows this genus to be applied from food additives to medicinal application.