## 4 Conclusions  
This study provided the first comparative metabolite profiling of cucumber and bottle gourd fruits via HR-UPLC/MS/MS based on GNPS-networking in both modes, allowing for annotation of 107 metabolites, i.e., amino acids (14), organic acids (6), phenolic/cinnamic acid derivatives (15), alkaloids (1), flavonoids (24), pterocarpans (3), alkyl glycosides (4), sesquiterpenenes (5), saponins (5), lignans (3), fatty acids/amides (16), and lysophospholipids (8). Overall, both fruits share an abundance of amino acids, organic acids, flavones-C-glycos, fatty acids and lysophospholipids in a comparable manner. However, triterpen saponins, alkaloids, flavones-C-glycosides acylated with ferulic or p-coumaric acids, alkyl glycosides, and pterocarpans were exclusively detected in cucumber, and the latter two classes were reported in this study for the first time to be present in Cucurbitaceae. On the other hand, bottle gourd was further distinguished by the presence of dimethylaxylated flavonoids acylated with malonic or acetic acids, lignans, and conjugatesof phenyl compounds with caffeic/ferulic acid-O-glycosides, all of which were reported for the first time in genus _Lagenaria_. Sesquiterpenes were more abundant in bottle gourd, except for cynaroside A, which was detected in both fruits for the first time. The herein-identified metabolites rationalized several of the reported pharmacological effects of both species and further promoted them for new in vitro and in vivo medicinal research. Several of the herein-detected phytochemicals require further bioactivity studies to study their potential health effects, e.g., pterocarpans, alkyl glycosides, and phenyl-cinnamic acids conjugates. Aroma profiling via SPME-GC/MS analysis detected 93 volatiles at comparable levels in both species, responsible for the pleasant aroma of bottle gourd, despite its enrichment with ketones and esters. 49 Silylated primary metabolites were detected in both species via GC/MS analysis at comparable levels, of which bottle gourd was further enriched with fatty acids, and cucumber with sugars. The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/foods12040771/s1](https://www.mdpi.com/article/10.3390/foods12040771/s1)]([https://www.mdpi.com/article/10.3390/foods12040771/s1](https://www.mdpi.com/article/10.3390/foods12040771/s1)), Table S1: Relative percentile of volatile constituents detected in _C. sativus_ and _L. sicteraria_ fruits via SPME/GCMS; Figure S1: Full molecular networking created using MS/MS data in positive ionization mode for _L. sicteraria_ (bottle gourd) and _C. sativus_ (cucumber) crude fruit extracts showing 1002 nodes and 1451 edges. All nodes are labeled with parent mass and edges are labelled with neutral loss values. The network is displayed as pie chart with orange and green colors representing distribution of the precursor ion intensity in the pumpkin and cucumber extracts respectively; Figure S2: Tandem MS/MS spectrum of N,N,N-Trimethyl tryptophan betaine (or Lenticin) alkaloid (peak 16) detected in _C. sativus_ fruit crude extract via HR-UPLC/MS/MS analysis in positive ionization mode; Figure S3: Tandem MS/MS spectrum of hydroxymethylphenyl-O-hexosylferuloyl-O-hexoside (peak 29) detected in _L. sicteraria_ fruit crude extract via HR-UPLC/MS/MS analysis in negative ionization mode; Figure S4: Tandem MS/MS spectrum of hydroxymethylphenyl -O-caffeoyl-O-hexoside (peak 31) detected in _L. sicteraria_ fruit crude extract via HR-UPLC/MS/MS analysis in negative ionization mode; Figure S5: Tandem MS/MS spectrum of hydroxybenzoic acid -O-feruloyl-O-hexoside (peak 36) detected in _L. sicteraria_ fruit crude extract via HR-UPLC/MS/MS analysis in negative ionization mode; Figure S6: Tandem MS/MS spectrum of cynaroside A sesquiterpene (peak 39) detected in both _L. sicteraria_ & C. sativus fruit crude extracts via HR-UPLC/MS/MS analysis in negative ionization mode; Figure S7: Tandem MS/MS spectrum ofbutanol-O-pentosyl-hexoside (peak 44) detected in _C.