Contents variation analysis of free amino acids, nucleosides and nucleobases in semen sojae praeparatum fermentation using UFLC-QTRAP MS

Influence of microorganisms on flavor substances and functional components of sojae semen praeparatum during fermentation: A study integrating comparative metabolomics and high-throughput sequencing

Sojae semen praeparatum (SSP), a fermented product known for its distinctive flavor and medicinal properties, undergoes a complex fermentation process due to the action of various microorganisms. Despite its widespread use, the effect of these microorganisms on the flavor compounds and functional components of SSP remains poorly understood. This study aimed to shed light on this aspect by identifying 20 metabolites as potential key flavor substances in SSP. Moreover, glycine and lysine were identified as crucial flavor substances. Additionally, 24 metabolites were identified as key functional components. The dominant microorganisms involved in the fermentation process were examined, revealing six genera of fungi and 12 genera of bacteria. At the species level, 16 microorganisms were identified as dominant through metagenome sequencing. Spearman correlation analysis demonstrated a strong association between dominant microorganisms and both flavor substances and functional components. Furthermore, the study validated the significance of four core functional microorganisms in improving the flavor and quality of SSP. This comprehensive exploration of functional microorganisms of SSP on key flavor substances/functional components during SSP fermentation. The study findings serve as a valuable reference for enhancing the overall flavor and quality of SSP.

Quality evaluation of Sojae Semen Praeparatum by HPLC combined with HS-GC-MS

Sojae Semen Praeparatum is a popular fermented legume product in China, with a delicious flavour and health benefits. However, the quality control methods for Sojae Semen Praeparatum are now incomplete, and there are no standards for defining its degree of fermentation. In this study, we introduced colour, acid value, ethanol-soluble extractives and six flavonoid components' content to evaluate the quality of Sojae Semen Praeparatum comprehensively. Multiple linear regression was used to streamline the 11 evaluation indicators to 4 and confirm the evaluating feasibility of the four indicators. The degree of fermentation and odour of Sojae Semen Praeparatum were analyzed on headspace-gas chromatography-mass, and two types of odours, 'pungent' and 'unpleasant', could distinguish over-fermented Sojae Semen Praeparatum. Our research developed fermentation specifications and quality standards for Sojae Semen Praeparatum.

Carboxyl-containing components delineation via feature-based molecular networking: A key to processing conditions of fermented soybean

Carboxyl-containing components (CCCs) was the key chemical markers for fermented soybean, whose composition and content would be dramatically changed during the fermentation processes. To select the optimal fermented conditions, a rapid and sensitive 5-(diisopropylamino)amylamine derivatization, ultra-high performance liquid chromatography-quadrupole-time-of-flight/mass spectrometry and feature-based molecular networking method was established for determination CCCs and the developed method was successfully applied to compare the dynamic changes of CCCs under different processing conditions. A total of 120 components were identified, the optimum fermentation conditions were the temperature at 30 °C, 50% humidity, with a 2-hour steaming time. Sixteen chemical markers with significant differences were screened. Furthermore, molecular docking technology was used to verify the antiperoxidative effect of these chemical markers. Accordingly, we focused on the high-content, little-studied active CCCs rather than the low-content and well-studied flavonoids. This study was helpful for the nutraceutical development and contributed scientific basis to further exploring quality evaluation of fermented food.

An Evaluation of Traits, Nutritional, and Medicinal Component Quality of Polygonatum cyrtonema Hua and P. sibiricum Red

Polygonati rhizoma (Huangjing in Chinese) is a traditional and classic dual-purpose material used in food and medicine. Herbalists in China and Japan have noticed several different rhizome types in Huangjing with different qualities. Rhizome of Polygonatum cyrtonema Hua and P. sibiricum Red. is divided into five types: "Jitou-type" Polygonati rhizoma (JTPR), atypical "Jitou-type" Polygonati rhizoma (AJTPR), "Jiang-type" Polygonati rhizoma (JPR), "Cylinder-type" Polygonati rhizoma (CPR), and "Baiji-type" Polygonati rhizoma (BJPR). This study observed the microstructure and histochemical localization of polysaccharides, saponins, and proteins in Huangjing. Nutritional and medicinal component data and antioxidant capacity (DPPH and ABTS) were analyzed to evaluate the quality of different types of Huangjing. The results showed that the comprehensive quality of the rhizomes, BJPR and JTPR, was better, regardless of their nutritional or medicinal values. Altogether, these results could recommend future breeding efforts to produce Huangjing with improved nutritional and medicinal qualities.

A Rapid High Throughput Vibration and Vortex-Assisted Matrix Solid Phase Dispersion for Simultaneous Extraction of Four Isoflavones for Quality Evaluation of Semen Sojae Praeparatum

Isoflavones (daidzein, daidzin, genistein and genistin) were main chemical components and usually selected as markers for quality control of Traditional Chinese Medicine semen sojae praeparatum (SSP). High throughput vibration and vortex-assisted matrix solid phase dispersion and high performance liquid chromatography with diode array detection were developed to simultaneously extract and quantify four isoflavones in SSP. Some parameters influencing extraction efficiency of isoflavones by vortex-assisted matrix solid phase dispersion such as sorbent type, ratio of sample to sorbent, crushing time, vibration frequency, methanol concentration, eluting solvent volume and vortex time were optimized. It was found that the best extraction yields of four isoflavones were obtained when the sample (20 mg) and SBA-3 (40 mg) was crushed by ball mill machine for 2 min at vibration frequency of 800 times per minute. Methanol/water (1.5 ml, 8:2, v/v) solution was dropped into the treated sample and vortexed for 3 min. The recoveries of the four isoflavones ranged from 86.1 to 94.8% and all relative standard deviations were less than 5%. A good linearity (r > 0.9994) was achieved within the range 0.5-125 μg/ml. It was concluded that the high throughput vibration and vortex-assisted matrix solid-phase dispersion coupled with high performance liquid chromatography was user-friendly extraction and quantification method of multiple isoflavones for quality evaluation of SSP.

Changes in free amino acids of fermented minced peppers during natural and inoculated fermentation process based on HPLC-MS/MS

Free amino acids (FAAs) participate in the synthesis of quality characteristic ingredients and taste substances in fermented minced peppers (FMPs), and they can be affected by fermentation method and time. In this study, changes in FAAs of FMP during natural fermentation (NF) and inoculated fermentation (IF) process were characterized by HPLC-MS/MS. The results showed that a total of 20 FAAs were identified, including 8 essential amino acids (AAs), 2 semiessential AAs, and 10 nonessential AAs. Comparing with other FAAs, Gln, Arg, and Asn presented higher content in the whole NF or IF periods. The FAAs content of NF and IF samples showed similar tendency during fermentation process, which first increased and then decreased. The highest content of most FAAs in IF and NF samples was obtained on the 18- and 12-day, respectively. Moreover, the FAA content in IF samples was higher than that in NF ones at the same fermentation time. The taste AAs content accounted for 23.3% to 50.0% in total FAAs, and taste activity value of bitter and umami was higher than sweet and aromatic ones. Based on principal component analysis, comprehensive analysis ranking, and heat map clustering analysis, FMP obtained by IF posed better FAAs quality than NF samples during fermentation process. PRACTICAL APPLICATION: Free amino acids (FAAs) participate in the synthesis of quality characteristic ingredients and taste substances in fermented minced peppers (FMPs), and they can be affected by fermentation method and time. Changes in FAA varieties and level in FMP during natural fermentation (NF) and inoculated fermentation (IF) process were analyzed using HPLC-MS/MS. Then, they were performed by principal component analysis (PCA), and clustered with the heat map. The results showed that FMP obtained by IF posed better FAAs quality than NF samples in the whole fermentation. HPLC-MS/MS was a reliable and effective mean for determining the FAAs and could provide regulation guidelines for improving the quality of FMP during fermentation process.

Simultaneous Characterization and Quantification of Varied Ingredients from Sojae semen praeparatum in Fermentation Using UFLC⁻TripleTOF MS

Systematic comparison of active ingredients in Sojae semen praeparatum (SSP) during fermentation was performed using ultra-fast liquid chromatography (UFLC)-TripleTOF MS and principal component analysis (PCA). By using this strategy, a total of 25 varied compounds from various biosynthetic groups were assigned and relatively quantified in the positive or negative ion mode, including two oligosaccharides, twelve isoflavones, eight fatty acids, N-(3-Indolylacetyl)-dl-aspartic acid, methylarginine, and sorbitol. Additionally, as the representative constituents, six targeted isoflavones were sought in a targeted manner and accurately quantified using extracted ion chromatograms (XIC) manager (AB SCIEX, Los Angeles, CA, USA) combined with MultiQuant software (AB SCIEX, Los Angeles, CA, USA). During the fermentation process, the relative contents of oligoses decreased gradually, while the fatty acids increased. Furthermore, the accurate contents of isoflavone glycosides decreased, while aglycones increased and reached a maximum in eight days, which indicated that the ingredients converted obviously and regularly throughout the SSP fermentation. In combination with the morphological changes, which meet the requirements of China Pharmacopoeia, this work suggested that eight days is the optimal time for fermentation of SSP from the aspects of morphology and content.

Safety evaluation of Semen Sojae Preparatum based on simultaneous LC-ESI-MS/MS quantification of aflatoxin B1 , B2 , G1 , G2 and M1

Semen Sojae Preparatum (SSP) is one of the most widely used traditional Chinese medicines, and is also a functional food. However, contamination with aflatoxins may occur in the fermentation process. To evaluate its safety, an accurate and rapid LC-ESI-MS/MS analytical method was developed and validated for the simultaneous determination of AFB₁ , AFB₂ , AFG₁ , AFG₂ and AFM₁ in SSP. After a simple ultrasonic extraction of SSP samples, chromatographic separation was achieved on an Agilent Zorbax SB-C₁₈ column (2.1 × 50 mm, 3.5 μm) with a flow rate of 0.50 mL/min. The gradient elution program was performed using a mobile phase consisting of water and acetonitrile, both containing 0.1% formic acid. Detection of five aflatoxins was based on triple quadrupole mass spectrometry using a multiple reaction monitoring mode with an electrospray ionization source. SSP is likely to be contaminated by aflatoxins in the processes of fermentation, storage, transportation and usage, and it is necessary to strictly monitor it. Artemisia annua L. and Morus alba L. may inhibit the production and growth of AFB₁ - and AFB₂ -producing fungi, which has a certain detoxification effect on contamination with aflatoxins in SSP.

A new strategy for statistical analysis-based fingerprint establishment: Application to quality assessment of Semen sojae praeparatum

Semen sojae praeparatum with homology of medicine and food is a famous traditional Chinese medicine. A simple and effective quality fingerprint analysis, coupled with chemometrics methods, was developed for quality assessment of Semen sojae praeparatum. First, similarity analysis (SA) and hierarchical clusting analysis (HCA) were applied to select the qualitative markers, which obviously influence the quality of Semen sojae praeparatum. 21 chemicals were selected and characterized by high resolution ion trap/time-of-flight mass spectrometry (LC-IT-TOF-MS). Subsequently, principal components analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were conducted to select the quantitative markers of Semen sojae praeparatum samples from different origins. Moreover, 11 compounds with statistical significance were determined quantitatively, which provided an accurate and informative data for quality evaluation. This study proposes a new strategy for "statistic analysis-based fingerprint establishment", which would be a valuable reference for further study.

Simultaneous high-performance liquid chromatography with diode array detection and time-of-flight mass spectrometric confirmation of the ten bioactive compounds in Semen Sojae Preparatum

Semen Sojae Preparatum is one of the most widely used traditional Chinese medicines. A reliable and accurate high-performance liquid chromatography with diode array detection method has been developed and validated for the quantitative determination of the ten bioactive compounds contained in Semen Sojae Preparatum. The samples were first extracted by pressurized liquid extraction using 80% ethanol at 100°C for 15 min and three static extraction cycles. Chromatographic separation was conducted on a C18 column using a mobile phase consisting of water and acetonitrile under gradient elution, and the detection wavelength was set at 210 nm. The samples were further analyzed on a high-performance liquid chromatography with time-of-flight mass spectrometry system to confirm the determination results. All the ten analytes were well separated, and the calibration curves showed good linearity. The intra- and interday precisions were evaluated in terms of relative standard deviation values within the ranges of 0.20-1.43% and 0.40-4.78%, respectively. The recoveries for the ten analytes were all in the ranges of 96.2-104.3%, with relative standard deviation values < 3.85%. The established high-performance liquid chromatography method could serve as a reliable and accurate method for the quality evaluation of Semen Sojae Preparatum from different origins.