Comprehensive Profiling of Phenolic Compounds in White and Red Chinese Bayberries (Morella rubra Sieb. et Zucc.) and Their Developmental Variations Using Tandem Mass Spectral Molecular Networking

Enhancing the terpenoid and flavonoid profiles and fruit quality in an elite Chinese bayberry line through hybridization

Chinese bayberry fruit is rich in bioactive compounds which are beneficial to health. Fruit hybridization can improve quality and metabolite content, but this has yet to be explored in bayberry. Here, we investigated the effects of hybridization on fruit quality and the metabolomic profile of a newly developed hybrid 'BD-107' compared to the parent 'Biqi' and 'Dongkui', the main cultivars in China. Physiochemical evaluations indicated that 'BD-107' outperformed both parental cultivars in crucial quality attributes such as firmness, sugar content, and vitamin C. Metabolomic analysis revealed that hybridization positively influenced the overall metabolite content, with the highest alterations in terpenoids (21.4 %) and flavonoids (12.2 %). Notably, the novel hybrid 'BD-107' contains seven unique metabolites that are not in either parent; Safranal, Myrcenon, p-Menth-3-en-1-ol, Balanophonin B, Swertisin, Genistein-8-C-glucoside, and Ethanone, 1-(1,4-dimethyl-3-cyclohexen-1-yl), linked to antioxidant and health-promoting properties. Our findings provide valuable insights into the influence of bayberry heterosis on terpenoid and flavonoid biosynthesis, enhancing bioactive metabolites and fruit quality, which meet the demand for health-promoting fruit.

Molecular network strategies combined with MCnebula2 identify potential active compounds from steamed Polygonatum cyrtonema Hua

Polygonatum cyrtonema Hua (PCH) underwent a series of transforms in its composition and had potential biological activities after steamed processing. In this study, LC-MS/MS datasets of chemical components in raw and steamed PCH were collected, and chemical profiling of PCH showed significant differences after steaming. Global Natural Products Social Molecular Network (GNPS-MN) combined with MCnebula2 were further used to annotate compound structures and data visualization. Through molecular network analysis, it is easier to discover the connections deduce the transformation of the components before and after steaming. Afterwards, the activity of transformed components was evaluated through cell models. Based on this strategy, 43 saponins and 31 flavonoid components were labeled in raw and steamed PCH. Among them, 27 saponins and 26 flavonoids were found only in steamed products, and the possible transformed pathways were speculated. Most saponins and flavonoids underwent glycosidic bond cleavage during the steaming process. Cell viability experiments indicated that steamed products improved renal fibrosis better than raw products, and the transformed components have better anti-renal fibrosis activity. This study reveals the influence of steaming on the chemical composition and structure, which provides a basis for subsequent exploration of active ingredients in steamed PCH.

Metabolomics combined with biochemical analyses revealed phenolic profiles and antioxidant properties of rapeseeds

Phenolic compounds, one of the most crucial lipid concomitants in rapeseed, have garnered heighten attention due to their numerous health benefits. Therefore, efficiently characterizing the phenolic profile of rapeseed is paramount for discerning their potential bioactivities. This study employed untargeted metabolomics in conjunction with molecular networking to trace the phenolic composition across three rapeseed genotypes. A total of 117 phenolic compounds were identified in rapeseed by mass spectrometry under positive and negative ionization modes, including 36 flavonoids, 23 coumarins, 12 phenolic acids, 10 lignans, 4 stilbenes, 4 diarylheptanes, 1 tannin, and several other phenolic constituents. Biochemical analyses revealed that Brassica napus rapeseed typically exhibited the highest total phenolic content and total flavonoid content as well as the strongest antioxidant capacity among three rapeseed genotypes. Through correlation analysis, 17 potential antioxidant phenolic compounds were tentatively screened from rapeseed, supporting the development and utilization of natural antioxidants from rapeseed.

Application of molecular networking to improve the compound annotation in liquid chromatography-mass spectrometry-based metabolomics analysis: A case study of Bupleuri radix

INTRODUCTION

Compound annotation is always a challenging step in metabolomics studies. The molecular networking strategy has been developed recently to organize the relationship between compounds as a network based on their tandem mass (MS2) spectra similarity, which can be used to improve compound annotation in metabolomics analysis.

OBJECTIVE

This study used Bupleuri Radix from different geographic areas to evaluate the performance of molecular networking strategy for compound annotation in liquid chromatography-mass spectrometry (LC-MS)-based metabolomics.

METHODOLOGY

The Bupleuri Radix extract was analyzed by LC-quadrupole time-of-flight MS under MSe acquisition mode. After raw data preprocessing, the resulting dataset was used for statistical analysis, including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The chemical makers related to the sample growth place were selected using variable importance in projection (VIP) > 2, fold change (FC) > 2, and p < 0.05. The molecular networking analysis was applied to conduct the compound annotation.

RESULTS

The score plots of PCA showed that the samples were classified into two clusters depending on their growth place. Then, the PLS-DA model was constructed to explore the chemical changes of the samples further. Sixteen compounds were selected as chemical makers and tentatively annotated by the feature-based molecular networking (FBMN) analysis.

CONCLUSION

The results showed that the molecular networking method fully exploits the MS information and is a promising tool for facilitating compound annotation in metabolomics studies. However, the software used for feature extraction influenced the results of library searching and molecular network construction, which need to be taken into account in future studies.

Systemic Analyses of Anti-Cell-Senescence Active Compounds in Camellia Sect. Chrysantha Chang and Their Mechanisms

Aging is an irreversible pathophysiological process for all organisms. The accumulation of senescent cells in pathological sites or tissues is recognized as the major cause of diseases and disorders during the aging process. Small molecules that reduce senescent cell burdens have gained increasing attention as promising intervention therapeutics against aging, but effective anti-senescence agents remain rare. Camellia Sect. Chrysantha Chang is documented as a traditional Chinese herbal medicine used by ethnic groups for many medical and health benefits, but its effect on aging is unclear. Here, we investigated the anti-senescence potential of eight C. Sect. Chrysantha Chang species. The results show that ethyl acetate fractions from these C. Sect. Chrysantha Chang species were able to delay the senescence of H9c2 cardiomyocytes except for C. pingguoensis (CPg). N-butanol fractions of C. multipetala (CM), C. petelotii var. grandiflora (CPt), and C. longzhouensis (CL) showed a senescent cell clearance effect by altering the expression levels of senescent-associated marker genes in the DNA-damage response (DDR) pathway and the senescent cell anti-apoptotic pathway (SCAPs). By using UPLC-QTOF-MS-based non-targeted metabolomics analyses, 27 metabolites from Sect. Chrysantha species were putatively identified. Among them, high levels of sanchakasaponin C and D in CM, CPt, and CL were recognized as the key bioactive compounds responsible for senescent cell clearance. This study is the first to disclose and compare the anti-cell-senescence effect of a group of C. Sect. Chrysantha Chang, including some rare species. The combination of senescent markers and metabolomics analyses helped us to reveal the differences in chemical constituents that target senescent cells. Significantly, contrary to the C. chrysantha var. longistyla (CCL), which is widely cultivated and commercialized for tea drinks, CM, CPt, and CL contain unique chemicals for managing aging and aging-related diseases. The results from this study provide a foundation for species selection in developing small-molecule-based drugs to alleviate diseases and age-related dysfunctions and may potentially be useful for advancing geroscience research.

Metabolomic analysis to unravel the composition and dynamic variations of anthocyanins in bayberry-soaked wine during the maceration process

In this work, we employed a global untargeted metabolomics technique to explore the intricate composition of anthocyanin constituents in bayberry wine and elucidate their alteration during the maceration process. Our analysis uncovered 20 distinct forms of anthocyanins in bayberry wine, including cyanidin-type, delphinidin-type, peonidin-type, malvidin-type, and other-type. 'Dongkui' (DK) bayberry wine was characterized by a predominance of glycoside forms of cyanidin-type and delphinidin-type anthocyanins, while 'Shuijing' (SJ) bayberry wine mainly contained other-type anthocyanins. Additionally, differential anthocyanins analyses conducted across various maceration periods demonstrated the different fate of the components in the wine, with a conspicuous decline in most glycosidic form anthocyanins. Moreover, correlation analysis revealed that the red hue of bayberry wine was primarily associated with cyanidin-3-O-glucoside, cyanidin-3-O-rhamnoside, delphinidin-3-O-arabinoside, and delphinidin-3-O-galactoside. This research contributes to our understanding of the anthocyanin composition and the dynamic variations in bayberry wine, opening avenues for further exploration and optimization of production techniques in the future.

The Effects of Different Drying Methods on the In Vitro Bioaccessibility of Phenolics, Antioxidant Capacity, and Morphology of European Plums (Prunes domestica L.)

Four different drying methods, hot-air-drying (HAD), vacuum-drying (VD), ultrasound-assisted vacuum-drying (US-VD), and freeze-drying (FD), were used to obtain dried plums (Prunes domesticaL.). These prunes were evaluated for their physical properties (such as color, rehydration ratio, and microstructural properties), phenolic compounds, and antioxidant activities before and after being subjected to in vitro digestion. TPC (total phenolic content) of plums ranged from 196.84 to 919.58 mg of GAE (gallic acid equivalent)/100 g of dw, and neochlorogenic acid was the most abundant phenolic compound. FD prunes had the highest levels of phenolics, whereas US-VD caused the most significant loss. During in vitro digestion, the phenolics were present at higher levels at the gastric medium but failed to maintain their stability at the small intestinal stage. Among the samples, FD along with HAD prunes exhibited a higher bioaccessibility index for most of the phenolic compounds. The ratios of TPC, TFC (total flavonoid content), and individual phenolics determined in the digested residues to the initial values of the undigested samples ranged from 0.23 to 31.03%. It could be concluded that the majority of the phenolics were extracted during digestion. Our findings showed that the different drying methods would alter the microstructure, which would affect the extractability and release of phenolics in the simulated digestion model.

T2T reference genome assembly and genome-wide association study reveal the genetic basis of Chinese bayberry fruit quality

Chinese bayberry (Myrica rubra or Morella rubra; 2n = 16) produces fruit with a distinctive flavor, high nutritional, and economic value. However, previous versions of the bayberry genome lack sequence continuity. Moreover, to date, no large-scale germplasm resource association analysis has examined the allelic and genetic variations determining fruit quality traits. Therefore, in this study, we assembled a telomere-to-telomere (T2T) gap-free reference genome for the cultivar 'Zaojia' using PacBio HiFi long reads. The resulting 292.60 Mb T2T genome, revealed 8 centromeric regions, 15 telomeres, and 28 345 genes. This represents a substantial improvement in the genome continuity and integrity of Chinese bayberry. Subsequently, we re-sequenced 173 accessions, identifying 6 649 674 single nucleotide polymorphisms (SNPs). Further, the phenotypic analyses of 29 fruit quality-related traits enabled a genome-wide association study (GWAS), which identified 1937 SNPs and 1039 genes significantly associated with 28 traits. An SNP cluster pertinent to fruit color was identified on Chr6: 3407532 to 5 153 151 bp region, harboring two MYB genes (MrChr6G07650 and MrChr6G07660), exhibiting differential expression in extreme phenotype transcriptomes, linked to anthocyanin synthesis. An adjacent, closely linked gene, MrChr6G07670 (MLP-like protein), harbored an exonic missense variant and was shown to increase anthocyanin production in tobacco leaves tenfold. This SNP cluster, potentially a quantitative trait locus (QTL), collectively regulates bayberry fruit color. In conclusion, our study presented a complete reference genome, uncovered a suite of allelic variations related to fruit-quality traits, and identified functional genes that could be harnessed to enhance fruit quality and breeding efficiency of bayberries.

Active colorimetric bilayer polycaprolactone-eucalyptus oil@silk fibroin-bayberry anthocyanins (PCL-EO@SF-BAs) membrane with directional water transport (DWT) for food packaging

Currently, designing smart membranes with multifunctional effectiveness is crucial to food freshness monitoring and retention. Herein, an active colorimetric Janus bilayer membrane with directional water transport (DWT) performance is constructed by electrospinning, which comprises a hydrophilic layer of silk fibroin-bayberry anthocyanins (SF-BAs) and a hydrophobic layer of polycaprolactone-eucalyptus oil (PCL-EO). The entities of BAs and EO are well dispersed in the fiber matrix by hydrogen bonds and physical interactions, respectively. BAs endow the membrane colorimetric response and antioxidant activity, and EO contributes to the antibacterial activity while DWT performance is generated from the asymmetric wettability of the two layers. The bilayer membrane has an accumulative one-way transport index of 1077%, an overall moisture management capacity of 0.76 and a water evaporation rate of 0.48 g h-1. Moreover, the release of BAs and EO was predominantly controlled by Fickian diffusion. As a pH-sensing indicator, PCL-EO@SF-BAs is highly sensitive to external pH stimuli and the response is reversible. In addition to freshness monitoring, PCL-EO@SF-BAs can extend the shelf-life of pork beyond 100% at 4 °C. Also, it can extend the shelf life of shrimp by approximately 70% at 25 °C with the synergistic effect of antibacterial activity and the DWT performance.

Expanding annotation of chemical compounds in hawthorn fruits and their variations in thermal processing using integrated mass spectral similarity networking

Chemical structural characterization of chemical compounds from hawthorn fruits and its thermal processed products was carried out in present study. By linking Global Natural Products Social (GNPS) Molecular Networking and MolNetEnhancer workflow, seventy-four chemical compounds in hawthorn fruits and its thermal processed products were tentatively identified. Three quercetagetin derivatives (quercetagetin-3-O-glucoside, quercetagetin-di-glucoside and its isomer), five quercetin or kaempferol derivatives (quercetin-acetylapiosyl-hexoside, quercetin-3-O-(6″-malonyl-hexoside), quercetin-3-O-(6″-malonyl-hexoside)-(1 → 2)-O-hexoside, quercetin-3-O-(6″-malonyl-hexoside)-(1 → 2)-O-deoxyhexoside, kaempferol-3-O-(6″-malonyl-hexoside)), six procyanidins including four (E)C-ethyl-procyanidins and two A-type procyanidins digallate, as well as 13 triterpenoids including ursolic aldehyde, triterpenoid glycosides, and triterpene acids were reported for the first time in hawthorn fruits. In addition, triterpenoids exhibited considerable thermal stability, while all of flavonoid glycosides, proanthocyanidins and 10 in 13 organic acids showed dramatic decrease after thermal processing.

MS/MS molecular networking-guided in-depth profiling of triterpenoid saponins from the fruit of Eleutherococcus senticosus and their neuroprotectivity evaluation

INTRODUCTION

Eleutherococcus senticosus fruit (ESF) is a natural health supplement resource that has been extensively applied as a tonic for the nervous system. The structures and neural bioactivities of triterpenoid saponins (TS), which are the major constituents of ESF, have not been comprehensively analyzed thus far.

OBJECTIVE

We conducted a complete in-depth MS/MS molecular networking (MN)-based targeted analysis of TS from the crude extract of ESF and investigated its neuroprotective value.

METHODS

An MS/MS MN-guided strategy was used to rapidly present a series of precursor ions (PIs) of TS in a compound cluster as TS-targeted information used in the discovery and characterization of TS. In addition, a prepared TS-rich fraction of ESF was assayed for its restraining effects on β-amyloid-induced inhibition of neurite outgrowth.

RESULTS

A total of 87 TS were discovered using a PI tracking strategy, 28 of which were characterized as potentially undescribed structures according to their high-resolution MS values. Furthermore, the TS-rich fraction can significantly reduce β-amyloid-induced damage to neural networks by promoting the outgrowth of neurites and axons.

CONCLUSION

Our findings reveal the richness of TS in ESF and will accelerate their application in the treatment of neurodegenerative diseases.

Targeted isolation of diterpenoids and sesquiterpenoids from Daphne gemmata E. Pritz. ex Diels using molecular networking together with network annotation propagation and MS2LDA

Investigation of the whole plant of Daphne gemmata E. Pritz. ex Diels (Thymelaeaceae) using molecular networking coupled to Network Annotation Propagation (NAP) and unsupervised substructure annotation (MS2LDA) led to the discovery of five tigliane diterpenoids, 14 guaiane sesquiterpenoids, one rhamnofolane diterpenoid and three carotene sesquiterpenoids. The structures of the eight undescribed compounds, daphnorbol A and daphnegemmatoids A-G, were characterized by detailed spectroscopic analyses, NMR and ECD calculations, application of Snatzke's method and single-crystal X-ray diffraction analysis. All isolated compounds were evaluated for their cytotoxic activities against HepG2, A549, and MCF-7 cells by MTT assay. Daphnorbol A exhibited significant cytotoxic activity against HepG2 and A549 cells with IC50 values of 4.06 μM and 6.35 μM, respectively. Prostratin showed potent cytotoxic activity against HepG2 and A549 cells with IC50 values of 6.06 μM and 5.45 μM, respectively. Further Hoechst 33,258 and AO-EB staining assays indicated that daphnorbol A and prostratin could induce apoptosis in HepG2 and A549 cells.

Comprehensive review of composition distribution and advances in profiling of phenolic compounds in oilseeds

A wide range of phenolic compounds participate in oilseed growth, regulate oxidative stability of corresponding vegetable oil, and serve as important minor food components with health-promoting effects. Composition distribution of phenolic compounds varied in oilseeds. Isoflavones, sinapic acid derivatives, catechin and epicatechin, phenolic alcohols, chlorogenic acid, and lignans were the main phenolic compounds in soybean, rapeseed, peanut skin, olive, sunflower seed, sesame and flaxseed, respectively. Among which, the total isoflavones content in soybean seeds reached from 1,431 to 2,130 mg/100 g; the main phenolic compound in rapeseed was sinapine, representing 70–90%; chlorogenic acid as the predominant phenolic compound in sunflower kernels, represented around 77% of the total phenolic content. With the rapid development of analytical techniques, it is becoming possible for the comprehensive profiling of these phenolic compounds from oilseeds. This review aims to provide recently developments about the composition distribution of phenolic compounds in common oilseeds, advanced technologies for profiling of phenolic compounds by the metabolomics approaches based on mass spectrometry. As there is still limited research focused on the comprehensive extraction and determination of phenolics with different bound-forms, future efforts should take into account the non-targeted, pseudo-targeted, and spatial metabolomic profiling of phenolic compounds, and the construction of phenolic compound database for identifying and quantifying new types of phenolic compounds in oilseeds and their derived products.

Combining NMR and MS to Describe Pyrrole-2-Carbaldehydes in Wheat Bran of Radiation

Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) are indispensable analytical tools to provide chemical fingerprints in metabolomics studies. The present study evaluated radiation breeding wheat lines for chemical changes by non-targeted NMR-based metabolomics analysis of bran extracts. Multivariate analysis following spectral binning suggested pyrrole-2-carbaldehydes as chemical markers of four mutant lines with distinct NMR fingerprints in a δ_H range of 9.28-9.40 ppm. Further NMR and MS data analysis, along with chromatographic fractionation and synthetic preparation, aimed at structure identification of marker metabolites and identified five pyrrole-2-carbaldehydes. Quantum-mechanical driven ¹H iterative full spin analysis (QM-HiFSA) on synthetic pyrrole-2-carbaldehydes provided a precise description of complex peak patterns. Biological evaluation of pyrrole-2-carbaldehydes was performed with nine synthetic products, and six compounds showed hepatoprotective effects via modulation of reactive oxygen species production. Given that three out of five identified in wheat bran of radiation were described for hepatoprotective activity, the value of radiation mutation to greatly enhance pyrrole-2-carbaldehyde production was supported.

Two Myricetin-Derived Flavonols from Morella rubra Leaves as Potent α-Glucosidase Inhibitors and Structure-Activity Relationship Study by Computational Chemistry

Diabetes mellitus (DM) is a chronic disease characterized by hyperglycemia, and oxidative stress is an important cause and therapeutic target of DM. Phytochemicals such as flavonols are important natural antioxidants that can be used for prevention and treatment of DM. In the present study, six flavonols were precisely prepared and structurally elucidated from Morella rubra leaves, which were screened based on antioxidant assays and α-glucosidase inhibitory activities of different plant tissues. Myricetin-3-O-(2″-O-galloyl)-α-L-rhamnoside (2) and myricetin-3-O-(4″-O-galloyl)-α-L-rhamnoside (3) showed excellent α-glucosidase inhibitory effects with IC50 values of 1.32 and 1.77 μM, respectively, which were hundredfold higher than those of positive control acarbose. Molecular docking simulation illustrated that the presence of galloyl group altered the binding orientation of flavonols, where it occupied the opening of the cavity pocket of α-glucosidase along with Pi-anion interaction with Glu304 and Pi-Pi stacked with His279. Pi-conjugations generated between galloyl moiety and key residues at the active site of α-glucosidase reinforced the flavonol-enzyme binding, which might explain the greatly increased activity of compounds 2 and 3. In addition, 26 flavonols were evaluated for systematic analysis of structure-activity relationship (SAR) between flavonols and α-glucosidase inhibitory activity. By using their pIC50 (-log IC50) values, three-dimensional quantitative SAR (3D-QSAR) models were developed via comparative molecular field analysis (CoMFA) and comparative similarity index analysis (CoMSIA), both of which were validated to possess high accuracy and predictive power as indicated by the reasonable cross-validated coefficient (q 2) and non-cross-validated coefficient (r 2) values. Through analyzing 3D contour maps of both CoMFA and CoMSIA models, QSAR results were in agreement with in vitro experimental data. Therefore, such results showed that the galloyl group in compounds 2 and 3 is crucial for interacting with key residues of α-glucosidase and the established 3D-QSAR models could provide valuable information for the prediction of flavonols with great antidiabetic potential.

An overview of the nutritional value, health properties, and future challenges of Chinese bayberry

Chinese bayberry (CB) is among the most popular and valuable fruits in China owing to its attractive color and unique sweet/sour taste. Recent studies have highlighted the nutritional value and health-related benefits of CB. CB has special biological characteristics of evergreen, special aroma, dioecious, nodulation, nitrogen fixation. Moreover, the fruits, leaves, and bark of CB plants harbor a number of bioactive compounds including proanthocyanidins, flavonoids, vitamin C, phenolic acids, and anthocyanins that have been linked to the anti-cancer, anti-oxidant, anti-inflammatory, anti-obesity, anti-diabetic, and neuroprotective properties and to the treatment of cardiovascular and cerebrovascular diseases. The CB fruits have been used to produce a range of products: beverages, foods, and washing supplies. Future CB-related product development is thus expected to further leverage the health-promoting potential of this valuable ecological resource. The present review provides an overview of the botanical characteristics, processing, nutritional value, health-related properties, and applications of CB in order to provide a foundation for further research and development.

A deep clustering-based mass spectral data visualization strategy for anti-renal fibrotic lead compound identification from natural products

We present a deep clustering-based MS data visualization strategy (MCnebula), integrated with the influential open-source automatic MS annotation platform SIRIUS and in vivo and in vitro methods, to screen and validate potential lead compounds from natural products.

Lignin as a MALDI matrix for small molecules: a proof of concept

Driven by the interest in metabolomic studies and the progress of imaging techniques, small molecule analysis is booming, while it remains challenging to be realized by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Herein, lignin, the second most abundant biomass in nature, was applied as a dual-ion-mode MALDI matrix for the first time to analyze small molecules. The low ionization efficiency and strong optical absorption properties make lignin a potential MALDI matrix in small molecule analysis. A total of 30 different small molecules were identified qualitatively and six kinds of representative molecules were detected quantitatively with a good linear response (R² > 0.995). To verify the accuracy of our quantitative method in MALDI, myricitrin, a major bioactive component in Chinese bayberry, was analyzed in different cultivars and tissues. The myricitrin content in real samples detected by MALDI was highly consistent (R² > 0.999) with that detected by high-performance liquid chromatography, thus indicating the applicability of the lignin matrix. Further characterization by ultraviolet and nuclear magnetic resonance spectroscopy was carried out to explain the possible mechanism of lignin as a matrix and provide more theories for a rational matrix design.

Metabolome Exploration by High-Resolution Mass Spectrometry Methodologies of Two New Yeast Species: Starmerella reginensis and Starmerella kourouensis

Nature is harnessed since ancient times to fulfill human needs, and yeast culture has been mastered for bakery, brewery, or the preparation of beverages. In this context, the two recently discovered yeast species Starmerella reginensis and Starmerella kourouensis, belonging to a genus related to fermentative activities in the literature, were explored via untargeted metabolomics approaches. Ultrahigh-performance liquid chromatography hyphenated with tandem mass spectrometry and a deep investigation of molecular networks and spectral data allowed the annotation of, respectively, 439 and 513 metabolites for S. reginensis and S. kourouensis, with approximatively 30% compound annotations and 40% chemical class annotations for both yeast strains. These analyses and Fourier transform ion cyclotron resonance mass spectrometry accurate metabolic profiles unveiled a rich content of alkaloids, lipids, amino acids, and terpenoids for S. reginensis. S. kourouensis presents a similar profile with more sulfated compounds. In short, these results enrich the current knowledge about Starmerella yeast secondary metabolites and reveal their significant structural diversity of small molecules.