Stevia rebaudiana (SR) is often used by the food industry due to its steviol glycoside content, which is a suitable calorie-free sweetener. Further, both in vitro and in vivo studies indicate that these glycosides and the extracts from SR have pharmacological and therapeutic properties, including antioxidant, antimicrobial, antihypertensive, antidiabetic, and anticancer. This work reviews the antiobesity, antihyperglycemic, antihypertensive, and antihyperlipidemic effects of the majority of glycosides and aqueous/alcoholic extracts from the leaves, flowers, and roots of the SR. These compounds can serve as a natural and alternative treatment for diseases that are associated with metabolic syndrome, thus contributing to health promotion.

The physicochemical and biochemical changes during the fermentation of four clones and two native varieties of Theobroma cacao L. were studied. Fermentation was performed in traditional wood cubes. During fermentation, the cotyledon pH decreased, and the temperature increased to more than 10 °C above the ambient temperature (47 °C). The fermentation index (FI) increased in the clones C1, C4, C8, C9, and Guayaquil (G) to close to one at 120 h of fermentation. For the FI of the cocoa Criollo (Cr), a value of 2.5 was proposed according to the spectrophotometric scan performance. The total polyphenol content increased in all the samples from 21 (C8) to 70 (Cr) % in a comparison of the TPC at T0 and T120, respectively. The total flavonoid content increased from 16 (C8) to 51% in Guayaquil (G) during the fermentation period. In the case of the methylxanthines, such as theobromine and caffeine, both quantities decreased. The theobromine content decreased in all the samples from 6 (G) to 31% (C8). The caffeine content decreased in all the samples from 3% in Cr to 25% in C1 and G after fermentation. The antioxidant capability did not change after 120 h of fermentation, and the amount of methylxanthines did not affect the antioxidant potential of the fermented cocoa. The FTIR scan of the fat-free cocoa showed significant differences between the unfermented and fermented beans, and several peaks assigned to carbohydrates and proteins decreased.

The Cocoa Pod Husk (CPH) accounts for 67–76% of the total cocoa fruit weight, making it its main agro-industrial waste of cocoa production. A valorization of this waste is possible through the extraction of pectin. In this study, pectin was extracted from CPH powder by acid hydrolysis using citric acid and sulfuric acid. Fourier transform infrared spectroscopy (FT-IR) was employed as a qualitative and quantitative characterization technique. The FT-IR of the pectin samples showed the bands visible at 1732 and 1626 cm⁻¹ corresponding to the esterified and free carboxylic groups, respectively. These bands can be differentiated according to their degree of methyl esterification (DE) by analyzing the area under the curve. The extracted pectin showed no significant difference in yields (p ≤ 0.05) between the two acids; however, significant differences (p ≤ 0.05) were observed in DE and methoxylation percentage (MeO). According to the FT-IR results, pectin extracted with citric acid presented a lower DE (7.43%) and MeO (1.12%) compared to pectin extracted with sulfuric acid, which showed a DE of 18.15% and a 2.96% MeO. Pectin with a DE below 50% is classified as low-methylated, making it unsuitable for the food industry. However, these create a raw material that has a potential use in the pharmaceutical and bioenergy industries.

The aim of this study was to investigate the potential of Amaranthus cruentus flavonoids (quercetin, kaempferol, catechin, hesperetin, naringenin, hesperidin, and naringin), cinnamic acid derivatives (p-coumaric acid, ferulic acid, and caffeic acid), and benzoic acids (vanillic acid and 4-hydroxybenzoic acid) as antioxidants, antidiabetic, and antihypertensive agents. An analytical method for simultaneous quantification of flavonoids, cinnamic acid derivatives, and benzoic acids for metabolomic analysis of leaves and inflorescences from A. cruentus was developed with HPLC-UV-DAD. Evaluation of linearity, limit of detection, limit of quantitation, precision, and recovery was used to validate the analytical method developed. Maximum total flavonoids contents (5.2 mg/g of lyophilized material) and cinnamic acid derivatives contents (0.6 mg/g of lyophilized material) were found in leaves. Using UV-Vis spectrophotometry, the maximum total betacyanin contents (74.4 mg/g of lyophilized material) and betaxanthin contents (31 mg/g of lyophilized material) were found in inflorescences. The leaf extract showed the highest activity in removing DPPH radicals. In vitro antidiabetic activity of extracts was performed with pancreatic α-glucosidase and intestinal α-amylase, and compared to acarbose. Both extracts exhibited a reduction in enzyme activity from 57 to 74%. Furthermore, the in vivo tests on normoglycemic murine models showed improved glucose homeostasis after sucrose load, which was significantly different from the control. In vitro antihypertensive activity of extracts was performed with angiotensin-converting enzyme and contrasted to captopril; both extracts exhibited a reduction of enzyme activity from 53 to 58%. The leaf extract induced a 45% relaxation in an ex vivo aorta model. In the molecular docking analysis, isoamaranthin and isogomphrenin-I showed predictive binding affinity for α-glucosidases (human maltase-glucoamylase and human sucrase-isomaltase), while catechin displayed binding affinity for human angiotensin-converting enzyme. The data from this study highlights the potential of A. cruentus as a functional food.

Cocoa drying is the post-harvest thermal process used to condition the beans to a moisture content between 6.5 and 7% for storage and further processing. Convective drying is an energy-intensive process where time and temperature are considered critical factors for the degradation of bioactive compounds in edible products. In the present study, the energy parameters, vibrational spectroscopy, and changes in bioactive compounds of cocoa beans were studied during thin-layer hot air drying at 50 °C, 60 °C, and 70 °C. Moisture loss, specific energy consumption (SEC), energy efficiency, total phenolics (TPs), total flavonoids (TFs), and antioxidant activity (DPPH) were determined. Fourier transform infrared (FT-IR) spectroscopy with attenuated total reflectance (ATR) was used to characterize the samples, and a multivariate analysis was applied to find interactions among the components. The obtained SEC was 18,947.30–24,469.51 kJ/kg, and the energy efficiency was 9.73–12.31%. When the temperature was 70 °C, the best values for SEC and energy efficiency were obtained. The results also showed that the convective drying generated changes in the TP levels for the three temperatures, mainly after 300 min, with maximum levels between 360 and 600 min, at 70 °C; however, it does not have a clear relationship with the TFs and the antioxidant activity. The FT-IR and the multivariate analysis revealed changes in several signals in the 1800 to 400 cm⁻¹ range, confirming the variation in the associated signal with phenolic compounds.

Biomass-derived activated carbons (ACs) are promising sustainable adsorbents for water polishing; however, their performance in real aqueous matrices cannot always be predicted from BET surface area alone. In this study, chemically activated biomass-derived carbonaceous adsorbents were prepared from Cocoa Pod Husk (CPH), Watermelon Peel (WP), and Pineapple Crown (PC) and evaluated for Chemical Oxygen Demand (COD) removal from real eutrophic lagoon water. The materials were characterized by N₂ adsorption–desorption analysis, including BET surface area and BJH pore-size assessment, XRD, Raman spectroscopy, FTIR, UV–Vis diffuse reflectance spectroscopy, and pH_PZC analysis. Although all adsorbents exhibited low N₂-BET surface areas, adsorption performance was governed by apparent functional pore accessibility inferred from adsorption behavior, pore size distribution, surface chemistry, structural disorder, electronic delocalization, and surface charge. Among the acid-activated samples, ACPCSA5 showed a narrow average pore size of 1.720 nm and achieved near-complete COD removal. Its superior performance was associated with oxygen-containing functional groups, partially developed sp² carbon domains, lower optical band gap, BJH-derived pore architecture, and favorable surface charge at lagoon pH. The Microbial Regrowth Potential Index (MRPI) was introduced only as a conservative COD-based proxy, not as a validated biological indicator. Overall, this work demonstrates that adsorption in real-water matrices depends on accessible pore architecture and multifunctional surface chemistry rather than BET surface area alone.