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L-Proline (L-Pro) and trans-4-hydroxy-L-proline (t-4-HPL) are major components of collagen and plant cell wall proteins. During their breakdown, free L-Pro and t-4-HPL are produced abundantly and play unique biological roles through complex metabolisms including isomerization. Therefore, it is essential to quantify all the six stereoisomers of proline and 4-hydroxyproline. Here, analytes were first labelled with 12C-dabsyl group, which has strong red colour and stability under light. Secondly, each of the 13C6-dabsyl stereoisomers were added to 12C-dabsylated samples as internal standards before cleanup. Finally, the molar ratio of 12C- and 13C6-dabsyl analytes was determined as the intensity ratio of doublet molecular ions with m/z difference of six in mass spectra, which were obtained by subjecting the cleaned sample to capillary chromatography-mass spectrometry. The total amounts of proline, t-4-HP and cis-4-hydroxyproline were determined using the standard addition method. Linear calibration curves (R2 > 0.99) were obtained in the range of 10-1000 pmol. To determine the molar ratio of D- and L-enantiomers, enantiopure dabsyl analyte fraction was obtained using reverse-phase and chiral chromatography. Mouse serum contained 0.20 μmol/L trans-4-hydroxy-D-proline. Achatina fulica haemolymph contained 0.070 μmol/L D-proline. The Santalum album wood powder contained all the 6 stereoisomers and unexpectedly the D-enantiomer was dominant for trans-4-hydroxyproline.
Background: Postpartum mental health challenges are increasingly recognized as a major public health concern, particularly during the early months after childbirth when emotional vulnerability is heightened. Although aerobic exercise is known to be associated with mood improvement, few large-scale studies have examined the acute psychological effects of a single exercise session in postpartum women, especially in contexts where environmental barriers restrict opportunities for physical activity. Methods: A total of 628 postpartum mothers (2-6 months postpartum) residing in a snowbound region of northern Japan participated in a single-session indoor bounce-based aerobic exercise program. Mood states were assessed immediately before and after the session using the validated Japanese short-form Profile of Mood States (POMS). Open-ended comments were also collected and analyzed thematically. Results: Paired analyses demonstrated significant acute improvements in key mood domains. Tension-Anxiety decreased (mean difference -7.91, 95% CI [-8.82, -7.00]; d = -0.68), and Anger-Hostility decreased (-4.61, 95% CI [-5.40, -3.82]; d = -0.45), while Vigor increased (11.82, 95% CI [10.47, 13.17]; d = 0.69) (all p < 0.001). In contrast, Depression-Dejection showed no significant change (-0.33, 95% CI [-1.30, 0.64]; p = 0.613). Conclusions: A single session of indoor bounce-based aerobic exercise was associated with immediate improvements in emotional well-being among postpartum women, particularly in anxiety-related and activation-related mood states. Because this exercise modality can be performed safely at home and is well suited to regions where outdoor physical activity is restricted, it may represent an accessible strategy for supporting postpartum mental health. Future research should examine longitudinal effects, controlled designs, and optimal program frequency to determine sustained benefits.
Background/Objectives: This study examined whether sharing a class with a peer with physician-diagnosed food allergy (FA) was associated with post-intervention FA comprehension among preschool children. Methods: A four-month ARCS motivation model-based digital nutrition education program was delivered to 163 five-year-old preschoolers from nine public kindergartens. The program provided instruction on knowledge of balanced diets and FA. Preschoolers were classified as inclusive (at least one peer with physician-diagnosed FA in the same class; n = 75) or non-inclusive (n = 88). Dietary balance and FA comprehension were assessed using illustrated worksheets. Ordinal logistic generalized estimating equations (GEE) accounted for clustering within kindergartens. Results: The inclusive environment was associated with higher FA comprehension (Wald χ2(1) = 4.750, p = 0.029; OR = 4.219, 95% CI: 1.156–15.399), whereas no association was observed for dietary balance (Wald χ2(1) = 0.053, p = 0.818; OR = 0.912, 95% CI: 0.414–2.008). Conclusions: The presence of a peer with FA was associated with higher post-intervention FA comprehension.
Gum arabic (GA) is a highly branched arabinogalactan-protein complex widely used in food and pharmaceutical industries. Its complex side chains contain L-arabinofuranose residues linked via α-(1→3) and α-(1→4) bonds, which represent the final structural barrier to complete enzymatic degradation of GA. Here, we isolated and characterized two complementary α-L-arabinofuranosidases, FoAF2 and FoAF3, from Fusarium oxysporum 12S. FoAF2, a glycoside hydrolase (GH) family 54 enzyme, preferentially cleaves α-(1→3)-arabinosyl residues while exhibiting weak activity toward α-(1→4) linkages at high enzyme concentrations. In contrast, the GH43_34 enzyme FoAF3 displays strict specificity for α-(1→4)-arabinosyl residues but requires prior removal of neighboring α-(1→3) substituents for efficient catalysis. Structural modeling using AlphaFold 3 revealed that the constrained catalytic pocket of FoAF3 is highly sensitive to steric hindrance from adjacent branches, explaining its dependence on sequential FoAF2 action for complete debranching. This two-enzyme system functions similarly to the bifunctional Bifidobacterium BIAraE, but achieves the same effect using separate enzymes rather than fused domains. Combined with previously characterized F. oxysporum enzymes, FoAF2 and FoAF3 complete a comprehensive toolkit enabling systematic GA degradation from complex side chains to monosaccharides. These findings provide molecular insights into the mechanisms underlying α-L-arabinofuranosidase specificity and establish a foundation for the enzymatic modification of GA for industrial applications.
