Herbs that are usually recognized as medicinal plants are well known for their therapeutic effects and are traditionally used to treat numerous diseases, including aging. This study aimed to evaluate the metabolite variations among six selected herbs namely Curcurma longa, Oenanthe javanica, Vitex negundo, Pluchea indica, Cosmos caudatus and Persicaria minus using proton nuclear magnetic resonance (1H-NMR) coupled with multivariate data analysis (MVDA). The free radical scavenging activity of the extract was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) and oxygen radical absorbance capacity (ORAC) assay. The anti-aging property was characterized by anti-elastase and anti-collagenase inhibitory activities. The results revealed that P. minus showed the highest radical scavenging activities and anti-aging properties. The partial least squares (PLS) biplot indicated the presence of potent metabolites in P. minus such as quercetin, quercetin-3-O-rhamnoside (quercitrin), myricetin derivatives, catechin, isorhamnetin, astragalin and apigenin. It can be concluded that P. minus can be considered as a potential source for an anti-aging ingredient and also a good free radical eradicator. Therefore, P. minus could be used in future development in anti-aging researches and medicinal ingredient preparations.

The present work aimed to compare the main ergogenic attributes of two commercialized stages (young and mature) of coconut water (CW) obtained from four coconut varieties. The changes of electrolytes and sugars in CW upon maturation were quantified by inductively coupled plasma mass spectrophotometer and high-performance liquid chromatography, respectively. Based on the electrolyte profiling, potassium yielded the highest amount (ranging from 237.41 to 361.20 mg/100 mL) followed by sodium, magnesium, calcium, iron, manganese, copper, selenium, and zinc across all the maturity stages tested. For sugars, there were lower amounts of fructose and glucose, but a higher amount of sucrose with the maturation of the fruits. In conclusion, the amount of beneficial nutrients in the form of sugars and minerals was higher than that of young CW, and the ergogenic attributes of mature CW especially from MATAG variety (M-MATAG) were the best to be exploited further in the development of natural energy drinks.

Several studies have demonstrated strong antioxidant activity of date fruits. Nevertheless, limited data is available for the bioactive compounds responsible for the activity. In this study, the antioxidant activity of five different date varieties (Ajwa, Anbara, Piyarom, Rabbi and Deglet Nour) extracted using 80% ethanol was determined using free radical scavenging (DPPH), ferric reducing power (FRAP) and antioxidant capacity (ABTS) assays. The 1 H-NMR was employed to profile the bioactive metabolites present in the dates. The obtained results demonstrated that the Piyarom extract had the highest total phenolic content (355 mg GAE/100g DW), total flavonoid content (57.07 mg/100g DW) and exhibited good antioxidant activity with IC 50 of 16.2 µg/mL, 26.38 mmol Fe (II)/g and 11.3 µg/mL for DPPH scavenging activity, FRAP antioxidant power and ABTS antioxidant capacity, respectively. The metabolites responsible for the variation between different date's varieties were successfully identified using 1 H-NMR-based metabolomics. The principal component analysis (PCA) and partial least squares (PLS) analysis depicted clear and distinct separations into three clusters representing the five date varieties. The metabolites responsible for the separation were identified as sucrose, betaine, fructose, ascorbic acid, glycine, and arginine. Correlation study from PLS biplot revealed that glucose, ascorbic acid, epicatechin, gallic acid, and citric acid are responsible for the antioxidant activity measured.

Plasmepsin II is a malarial pepsin-like aspartic protease produced as a zymogen containing an N-terminal prosegment domain that is removed during activation. Despite structural similarities between active plasmepsin II and pepsin, their prosegments adopt different conformations in the respective zymogens. In contrast to pepsinogen, the proplasmepsin II prosegment is 80 residues longer, contains a transmembrane region and is non-essential for recombinant expression in an active form, thus calling into question the prosegment's precise function. The present study examines the role of the prosegment in the folding mechanism of plasmepsin II. Both a shorter (residues 77-124) and a longer (residues 65-124) prosegment catalyze plasmepsin II folding at rates more than four orders of magnitude faster compared to folding without prosegment. Native plasmepsin II is kinetically trapped and requires the prosegment both to catalyze folding and to shift the folding equilibrium towards the native conformation. Thus, despite low sequence identity and distinct zymogen conformations, the folding landscapes of plasmepsin II and pepsin, both with and without prosegment, are qualitatively identical. These results imply a conserved and unusual feature of the pepsin-like protease topology that necessitates prosegment-assisted folding.

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