Effect of silver nanoparticles foliar application on the nutritional properties of potato tubers.

The aim of presented study was to test nutritional properties of potato tubers and silver ions accumulation pattern after foliar application of silver nanoparticles (AgNPs) during potato vegetation. Potato plants were sprayed with different concentration of Ag nanoparticles (0.1, 1.0 and 10 mg·dm-3) synthesized with incorporation with sodium dodecyl sulphate (SDS) and sodium citrate as stabilizing agent. The lowest amounts of silver ions were transported to the tubers after spraying with AgNPs synthesized with SDS, rather than with citrate. Nevertheless silver ions accumulation in tubers was negligible. SDS method of synthesis was more favourable in terms of nutritional properties of potato tubers. The highest tested concentration of AgNPs_SDS had a favourable effect on a variety of macro- and micronutrients, ascorbic acid and soluble sugars. In turn, lower concentrations of AgNPs_SDS increased the content of phenolic compounds and free radical scavenging efficiency of tubers. These correlations were also confirmed by Principal Component Analysis.

Copper (II)-catalyzed polydopamine mediated photothermal sensors for visual quantitative point-of-care testing.

BACKGROUND: Temperature sensing is commonly used in point-of-care (POC) detection technologies, yet the portability and convenience of use are frequently compromised by the complexity of thermosensitive processes and signal transduction. Especially, multi-step target recognition reactions and temperature measurement in the reaction vessel present challenges in terms of stability and integration of detection devices. To further combine photothermal reaction and signal readout in one assay, these two processes enable to be integrated into miniaturized microfluidic chips, thereby facilitating photothermal sensing and achieving a simple visual temperature sensing as POC detection. RESULTS: A copper ion (Cu2+)-catalyzed photothermal sensing system integrated onto a microfluidic distance-based analytical device (µDAD), enabling the visual, portable, and sensitive quantitative detection of multiple targets, including ascorbic acid, glutathione, and alkaline phosphatase (ALP). The polydopamine nanoparticles (PDA NPs) were synthesized by the regulation of free Cu2+ through redox or coordination reactions, facilitating the transduction of distinct photothermal response signals and providing the versatile Cu2+-responsive sensing systems. Promoted by integration with a photothermal µDAD, the system combines PDA's photothermal responsiveness and thermosensitive gas production of ammonium bicarbonate for improved sensitivity of ALP detection, reaching the detection limit of 9.1 mU/L. The system has successfully achieved on-chip detection of ALP with superior anti-interference capability and recoveries ranging from 96.8 % to 104.7 %, alongside relative standard deviations below 8.0 %. SIGNIFICANCE AND NOVELTY: The µDAD design accommodated both the photothermal reaction of PDA NPs and thermosensitive gas production reaction, achieving the rapid sensing of visual distance signals. The µDAD-based Cu2+-catalyzed photothermal sensing system holds substantial potential for applications in biochemical analysis and clinical diagnostics, underscored by the versatile Cu2+ regulation mechanism for a broad spectrum of biomarkers.

Effect of microwave combined with ethanol pretreatment on the quality of potato CO2 explosion puffing drying.

To enhance the drying quality of potato slices, this investigation employed a microwave heating (MH) combined with ethanol osmotic dehydration (EOD) pretreatment strategy to improve the quality of explosion puffing drying (EPD). This paper systematically investigated the effects of different pretreatment methods (no treatment, HAD, MH, EOD, MH+EOD) on the quality and physicochemical properties of potato slices subjected to CO2-EPD. The results showed that after MH and EOD pretreatments, the internal pores of the potato slices exhibited a uniform porous structure. The MH+EOD+CO2-EPD treatment demonstrated superior expansion, crispness, hardness, and color, with higher retention rates of vitamin C and protein. The measurements were an expansion ratio of 2.15, hardness of 1290.01 g, crispness of 745.94 g, ΔE of 6.54, protein content of 1.99 g/100 g, and VC content of 17.33 mg/100 g. Additionally, the study explored the effects of microwave power, microwave drying time, ethanol concentration, and ethanol soaking time on the expansion ratio, hardness, crispness, protein content, VC content, and color. MH+EOD+CO2-EPD is an environmentally sustainable and efficient solution with potential for widespread industrial application to enhance processing quality and economic benefits.

[Nutritional components of 5 potatoes in Anqing City in 2021].

OBJECTIVE: To analyze the nutrient composition and nutritional value evaluation of 5 potatoes in Anqing City. METHODS: According to the requirements of the Technical Manual for Food Composition Monitoring Projects, 5 types of potato samples were collected from Anqing City, Anhui Province. National standard detection method were used to determine the nutritional components such as water, ash, protein, fat, dietary fiber, sugar, minerals, vitamins, and amino acids in the samples. The index of nutritional quality(INQ) method was used to evaluate proteins, vitamins, and minerals, and the amino acid scoring standard mode(FAO/WHO mode) was used to evaluate the nutritional value of amino acids. RESULTS: Among the 5 types of potatoes, purple potato had the highest protein(2.3 g/100 g) and dietary fiber content(3.6 g/100 g). Sweet potato(red) had the highest carotene content(4003 µg/100 g), sweet potato(white) had the highest content of vitamin C(15.4 mg/100 g). Sugar in potatoes mainly existed in three forms: fructose, glucose, and sucrose; Purple potatoes had the highest levels of calcium(47 mg/100 g) and phosphorus(74 mg/100 g), respectively. Potatoes(white) had the highest content of potassium(401 mg/100 g), while sweet potatoes(red) had the highest content of magnesium(31 mg/100 g). Sodium(104.0 mg/100 g), iron(0.9 mg/100 g), copper(0.17 mg/100 g), and manganese(0.40 mg/100 g) had the highest content in sweet potatoes(white). The Na/K ratio range of the 5 potato varieties was 0.003-0.456, and the INQ of phosphorus, potassium, magnesium, copper, and manganese were greater than 1. The detection result of 5 potatoes all contain 18 amino acids, and aspartic acid was the highest. The amino acid score(AAS) was 0.29-1.35, and the ratio coefficient(RC) was 0.47-1.69. CONCLUSION: The 5 types of potatoes are rich in dietary fiber, vitamin C and minerals, and belong to the high potassium and low sodium type of food. Potatoes can meet the daily needs of the human body for phosphorus, potassium, magnesium copper, and manganese elements. Lysine is rich in content and can be used as a nutritional supplement for grains. The AAS score and RC are close to 1, and the AAS evaluation mode is closer to the human amino acid composition mode, which can meet the daily needs of the human body for this essential amino acid.

[Nutritional composition of three cities restaurants in Shandong Province in 2021].

OBJECTIVE: To understand the current status of protein, fat, carbohydrates, energy, vitamins, minerals and other contents in common dishes of large, small, and medium-sized restaurants in Shandong Province. METHODS: From July to October 2021, 90 Shandong cuisine dishes were collected from 9 large, medium, and small restaurants in Shandong Province. One dish was collected from each restaurant, and samples from different types of restaurants were mixed as one sample. The content of nutrients and their carbohydrate and energy levels were detected and calculated. RESULTS: The median fat and protein content detected in the 90 dishes collected were 7.7 and 6.8 g/100 g, respectively. The calculated median values of energy and carbohydrates were 528 kJ/100 g and 5.4 g/100 g, respectively. The energy supply ratio of carbohydrates per 100 g of dishes was 17.2%, fat was 55.3%, and protein was 21.4%. The content of vitamin A, vitamin B_1, vitamin B_2, vitamin C and vitamin E was trace(tr)-26 700 µg/100 g, tr-0.12 mg/100 g, tr-0.40 mg/100 g, tr-56.5 mg/100 g and tr-5.31 mg α-TE/100 g. The medium number of dishes and potassium content was 375 and 219 mg/100 g. The detection rate of trans fat acid was 81.1%, and the median content was 0.06 g/100 g. CONCLUSION: The energy supply ratio of protein and fat in dishes is relatively high, while the energy supply ratio of total carbohydrates is relatively low. The sodium content is high, showing the characteristics of high sodium and low potassium. Vitamin, especially vitamin B_1 and vitamin B_2, has a low content.

Assessment of Selected Chemical and Morphological Properties of Lonicera var. kamtschatica and Lonicera var. emphyllocalyx Treated with Gaseous Ozone.

Lonicera caerulea L. fruits are a rich source of vitamins, organic acids, and phenolic compounds, which are characterised by their health-promoting properties. The content of bioactive compounds in this fruit may vary depending on the cultivar and the harvest date. This study analysed the effect of applying 5 ppm gaseous ozone for 1, 3, and 5 min on the chemical properties of L. kamtschatica varieties and newly created clones of L. emphyllocalyx for three years of cultivation. The fruits harvested from L. emphyllocalyx, depending on the year of harvest, had significantly larger size and weight compared to L. kamtschatica. On average, the acidity of the L. emphyllocalyx clones was 6% higher than other tested varieties. The average content of ascorbic acid was highest in L. emphyllocalyx clone '21-17'-57.80 mg·100 g-1; the year of harvest will significantly affect the content of vitamin C, reaching the highest level in 2022-53.92 mg·100 g-1. The total content of polyphenols was significantly dependent on the year of cultivation; reaching, on average, 54.8% more in 2022 compared to the rest of the years. The total antioxidant value using the FRAP, DPPH, and ABTS methods varied depending on the variety; exposure to ozone significantly increased the antioxidant value in each case. On the basis of the study, both botanical varieties can be used in food processing. Gaseous ozone exposure can significantly influence chemical composition, increasing the health-promoting value of fruit.

Changes in fruit quality properties and phytochemical substances of kiwifruit (Actinidia deliciosa) grown in different agro-ecological conditions during cold storage.

BACKGROUND: The changes in the physical structures of the products are the first things that consumers pay attention to. Therefore, it is essential and significant importance to take measures to improve the storage conditions of products and to minimize quality losses. The main objective of the study was to evaluate the effects of agro-ecological conditions on bioactive compounds and fruit quality of kiwifruit during cold storage. The 'Hayward' kiwifruit cultivar grown in Ordu, Giresun, Samsun, Rize, and Yalova provinces of Türkiye were kept at 0 ± 0.5 °C and relative humidity of 90 ± 5% for 150 d. RESULTS: The kiwifruit obtained from the provinces of Yalova, Ordu, and Giresun experienced the least weight loss during cold storage. Kiwifruit from Samsun and Yalova provinces had the lowest fruit firmness, while those from Giresun had the highest on 150th d. The changes were observed in the skin and flesh colors of the kiwifruit belonging to all cultivation areas. The amount of vitamin C increased throughout the study in all ecological conditions, but the Yalova province's kiwifruit was found to have the highest levels. Additionally, in all ecologies, kiwifruit showed an increase in antioxidant activity, total phenolics, and total flavonoids, all known to have beneficial effects on human health. The total antioxidant activity and total phenolics were highest in the kiwifruit of Yalova province, but the total flavonoids were found in the kiwifruit of Rize and Ordu provinces. CONCLUSION: The study's results revealed that kiwifruit's bioactive compounds and quality parameters may vary depending on the cultivation area. Additionally, it can be stated that Yalova province kiwifruit experiences the least amount of postharvest quality losses.

Visual Sensor Array for Multiple Aromatic Amines via Specific Ascorbic Acid Oxidase Mimic Triggered Schiff-Base Chemistry.

Redox nanozymes have exhibited various applications in recognizing environmental pollutants but not aromatic amines (a type of typical pollutant). Herein, with Cu2+ as a node and tryptophan (Trp) as a linker, Cu-Trp as a specific ascorbic acid oxidase mimic was synthesized, which could catalyze ascorbic acid (AA) oxidation to dehydroascorbic acid (DHAA). Alternatively, with other natural amino acids as linkers to synthesize Cu-based nanozymes, such catalytic performances are also observed. The as-produced DHAA could react with o-phenylenediamine (OPD) and its derivatives (2,3-naphthalene diamine (NDA), 4-nitro-o-phenylenediamine (4-NO2-OPD), 4-fluoro-o-phenylenediamine (4-F-OPD), 4-chloro-o-phenylenediamine(4-Cl-OPD), and 4-bromo-o-phenylenediamine(4-Br-OPD)) to form a Schiff base and emit fluorescence. Based on the results, with Cu-Trp + AA and Cu-Arg (with arginine (Arg) as a linker) + AA as two sensing channels and extracted red, green, and blue (RGB) values from emitted fluorescence as read-out signals, a visual sensor array was constructed to efficiently distinguish OPD, NDA, 4-NO2-OPD, 4-F-OPD, 4-Cl-OPD, and 4-Br-OPD as low as 10 µM. Such detecting performance was further confirmed through discriminating binary, ternary, quinary, and senary mixtures with various concentration ratios, recognizing 18 unknown samples, and even quantitatively analyzing single aromatic amine. Finally, the discriminating ability was further validated in environmental waters, providing an efficient assay for large-scale scanning levels of multiple aromatic amines.

Optimal Brassicaceae family microgreens from a phytochemical and sensory perspective.

Microgreens, also called superfoods, emerge because of their high levels of nutrients, diverse flavour profiles, and sustainable cultivation methods, which make them culinary delights and valuable to a healthy and flavorful diet. The present study investigated Brassicaceae family microgreens, proposing a novel system (quality indices) that allows scoring among them. Fourteen Brassica microgreen species were morphological, phytochemical, and sensorial investigated. The morphological assessment revealed that radish microgreens exhibited the highest leaf area (p < 0.05), while red mizuna demonstrated superior yield. Cauliflower microgreens contained the highest concentrations of ascorbic acid (HPLC-DAD) and total phenolic content (p < 0.05). Phytochemical analysis using HPLC-MS/MS identified over 18 glucosinolates and phenolic compounds. Red mustard and red cabbage showed the highest glucosinolate content (p < 0.05). Watercress exhibited the highest phenolic compound content (p < 0.05), primarily flavonoids, while broccoli and radish contained the highest isothiocyanate levels. Cauliflower microgreens resulted in the most consumer-accepted variety. Appling quality indices scoring system identified radish, cauliflower, and broccoli microgreens as the most promising species. This study underscores the potential of Brassica microgreens as an excellent source of health-promoting phytochemicals with favorable market acceptance, providing valuable insights for both nutritional research and commercial applications.

Synthesis of lipophilic vitamin C and evaluation of its antioxidant performance in sunflower seed oil frying.

The present study involved the synthesis and analysis of a lipophilic form of vitamin C, namely tetrabutyryl vitamin C ester (TVCE). TVCE is synthesized by a simple one-step method, combining the advantages of VC and butyric acid. Its antioxidant efficacy on sunflower seed oil frying was evaluated by assessing lipid oxidation parameters including peroxide number (POV), carbonyl number (CV), and paraniline number (pAV). Furthermore, changes in the fatty acid composition of the oil were monitored using techniques such as infrared spectroscopy (IR), nuclear magnetic resonance (NMR), and gas chromatography (GC). The findings demonstrated that lipophilic vitamin C exhibited superior protection against oxidation during frying compared to vitamin E, suggesting that it may be an effective fat-soluble antioxidant. The study provides a new field for the utilization of vitamin C and a new idea for the development of efficient antioxidants.

Nanoflower Microreactor Based Versatile Enhancer for Recognition Cofactor-Dependent Enzyme Biocatalysis toward Saxitoxin Detection.

Investigating organic carriers' utilization efficiency and bioactivity within organic-inorganic hybrid nanoflowers is critical to constructing sensitive immunosensors. Nevertheless, the sensitivity of immunosensors is interactively regulated by different classes of biomolecules such as antibodies and enzymes. In this work, we introduced a new alkaline phosphatase-antibody-CaHPO4 hybrid nanoflowers (AAHNFs) microreactor based colorimetric immunoprobe. This system integrates a biometric unit (antibody) with a signal amplification element (enzyme) through the biomineralization process. Specifically, the critical factors affecting antibody recognition activity in the formation mechanism of AAHNFs are investigated. The designed AAHNFs retain antibody recognition ability with enhanced protection for encapsulated proteins against high temperature, organic solvents, and long-term storage, facilitating the selective construction of lock structures against antigens. Additionally, a colorimetric immunosensor based on AAHNFs was developed. After ascorbic acid 2-phosphate hydrolysis by alkaline phosphatase (ALP), the generated ascorbic acid decomposes I2 to I-, inducing the localized surface plasmon resonance in the silver nanoplate, which is effectively tuned through shape conversion to develop the sensor. Further, a 3D-printed portable device is fabricated, integrated with a smartphone sensing platform, and applied to the data of collection and analysis. Notably, the immunosensor exhibits improved analytical performance with a 0.1-6.25 ng·mL-1 detection range and a 0.06 ng·mL-1 detection limit for quantitative saxitoxin (STX) analysis. The average recoveries of STX in real samples ranged from 85.9% to 105.9%. This study presents a more in-depth investigation of the recognition element performance, providing insights for improved antibody performance in practical applications.

Highly Sensitive Biosensors Based on All-PEDOT:PSS Organic Electrochemical Transistors with Laser-Induced Micropatterning.

Recent advances in numerous biological applications have increased the accuracy of monitoring the level of biologically significant analytes in the human body to manage personal nutrition and physiological conditions. However, despite promising reports about costly wearable devices with high sensing performance, there has been a growing demand for inexpensive sensors that can quickly detect biological molecules. Herein, we present highly sensitive biosensors based on organic electrochemical transistors (OECTs), which are types of organic semiconductor-based sensors that operate consistently at low operating voltages in aqueous solutions. Instead of the gold or platinum electrode used in current electrochemical devices, poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) was used as both the channel and gate electrodes in the OECT. Additionally, to overcome the patterning resolution limitations of conventional solution processing, we confirmed that the irradiation of a high-power IR laser (λ = 1064 nm) onto the coated PEDOT:PSS film was able to produce spatially resolvable micropatterns in a digital-printing manner. The proposed patterning technique exhibits high suitability for the fabrication of all-PEDOT:PSS OECT devices. The device geometry was optimized by fine-tuning the gate area and the channel-to-gate distance. Consequently, the sensor for detecting ascorbic acid (vitamin C) concentrations in an electrolyte exhibited the best sensitivity of 125 µA dec-1 with a limit of detection of 1.3 µM, which is nearly 2 orders of magnitude higher than previous findings. Subsequently, an all-plastic flexible epidermal biosensor was established by transferring the patterned all-PEDOT:PSS OECT from a glass substrate to a PET substrate, taking full advantage of the flexibility of PEDOT:PSS. The prepared all-plastic sensor device is highly cost-effective and suitable for single-use applications because of its acceptable sensing performance and reliable signal for detecting vitamin C. Additionally, the epidermal sensor successfully obtained the temporal profile of vitamin C in the sweat of a human volunteer after the consumption of vitamin C drinks. We believe that the highly sensitive all-PEDOT:PSS OECT device fabricated using the accurate patterning process exhibits versatile potential as a low-cost and single-use biosensor for emerging bioelectronic applications.

Dual oxidative stress biomarkers co-recognition in periodontal microenvironment: A flexible and low-power consumption nanozyme sensing platform.

Sensing platforms with high interference immunity and low power consumption are crucial for the co-detection of dual oxidative stress biomarkers and clinical diagnosis of periodontitis. Herein, we constructed a bifunctional nanozyme to identify hydrogen peroxide (H2O2) and ascorbic acid (AA) with low crosstalk at zero or low bias voltage. To target H2O2 and AA, Fe(III) meso-tetra(4-carboxyphenyl) porphine (TCPP(Fe)) and Pt nanoclusters were selected as active sites respectively, and titanium carbide nanosheets were additionally introduced as a sensitizer. Due to their highly efficient catalytic properties, self-powered detection of H2O2 without bias voltage and distinguishable AA detection at 0.45 V were successfully achieved. Density functional theory calculations further confirmed the binding sites for target molecules and elucidated the sensing mechanism. On this basis, a dual-channel screen-printed electrode was fabricated to further ensure the discriminative detection of dual biomarkers at the device level. The constructed flexible, low-power consumption sensing platform was successfully applied to raw clinical samples, effectively distinguishing between healthy individuals and patients with varying degrees of periodontitis. This work is expected to provide new insights into the design of highly specific nanozymes and low-power consumption electrochemical sensing systems, which will contribute to the accurate and convenient diagnosis of periodontitis.

Electrochemical Determination of Dopamine with a Carbon Paste-Lanthanum (III) Oxide Micro-Composite Electrode: Effect of Cetyl Trimethyl Ammonium Bromide Surfactanton Selectivity.

This paper presents a new application of a lanthanum oxide (III)-modified carbon paste electrode (LaOX/CPE) for dopamine (DP) detection in the presence of ascorbic acid (AA). The presence of cetyl trimethyl ammonium bromide (CTAB) facilitated the LaOX/CPE electrode's ability to detect DP amidst AA interference, resulting in a substantial 70.0% increase in the anodic peak current for DP when compared to the unmodified carbon paste electrode (CPE). CTAB enabled clear separation of the anodic peaks for DP and AA by nearly 0.2 V, despite their initially overlapping potential values, through the ion-dipole interaction of AA and CTAB. The electrode was characterized using cyclic voltammetry (CV) and energy-dispersive spectroscopy (EDS). The method demonstrated a detection limit of 0.06 µmol/L with a relative standard deviation (RSD) of 6.0% (n = 15). Accuracy was assessed through the relative error and recovery percent, using urine samples spiked with known quantities of DP.

Efficient Estimation of ascorbic acid in vitamin C tablets enabled by phase-transfer strategy.

In this paper, we introduced a novel phase-transfer strategy tailored for the efficient batch detection of ascorbic acid in vitamin C tablets. This method entailed the reaction between ascorbic acid and an excess of potassium permanganate. Subsequent reaction of the residual potassium permanganate with sodium oxalate in an acidic medium led to the generation of carbon dioxide. The quantification of the produced carbon dioxide was achieved using headspace GC, enabling the indirect measurement of ascorbic acid. The obtained findings revealed that the headspace method exhibited satisfied precision with a relative standard deviation of less than 2.11 % and high sensitivity with a limit of quantitation of 0.27 µmol. These results firmly establish the reliability of this innovative approach for determining ascorbic acid. In addition, the highly automated feature of headspace method significantly enhances the efficiency of batch sample detection and reduces the errors caused by human operation. Thus, the adoption of the transformed phase strategy has demonstrated its effectiveness in assessing ascorbic acid, especially for large-scale sample analysis in industrial applications, owing to its efficiency, precision, and sensitivity.

Functional Nutrients and Jujube-Based Processed Products in Ziziphus jujuba.

Jujube (Ziziphus jujuba Mill.) is the first tree species in China, with a long history and abundant yield. However, fresh jujubes have a short shelf-life and are not resistant to storage. Therefore, more and more processed jujube products are being studied. These processed products can extend the shelf-life of jujubes and attract widespread attention for their rich functional nutrients. This review summarized changes in nutrients of fresh jujube and processed products and the research progress of different preparation methods of jujubes. Meanwhile, the pharmacological effects of bioactive components in jujube-based products were concluded. Jujube and its processed products contain rich polysaccharides, vitamin C, and other functional nutrients, which are beneficial to humans. As the initial processing method for jujubes, vacuum freezing or microwave drying have become the most commonly used and efficient drying methods. Additionally, processed jujube products cannot be separated from the maximum retention of nutrients and innovation of flavor. Fermentation is the main deep-processing method with broad development potential. In the future, chemical components and toxicological evaluation need to be combined with research to bring consumers higher quality functional jujube products and ensure the sustainable development of the jujube industry.

Au24Cd Nanoenzyme Coating for Enhancing Electrochemical Sensing Performance of Metal Wire Microelectrodes.

Dopamine (DA), ascorbic acid (AA), and uric acid (UA) are crucial neurochemicals, and their abnormal levels are involved in various neurological disorders. While electrodes for their detection have been developed, achieving the sensitivity required for in vivo applications remains a challenge. In this study, we proposed a synthetic Au24Cd nanoenzyme (ACNE) that significantly enhanced the electrochemical performance of metal electrodes. ACNE-modified electrodes demonstrated a remarkable 10-fold reduction in impedance compared to silver microelectrodes. Furthermore, we validated their excellent electrocatalytic activity and sensitivity using five electrochemical detection methods, including cyclic voltammetry, differential pulse voltammetry, square-wave pulse voltammetry, normal pulse voltammetry, and linear scanning voltammetry. Importantly, the stability of gold microelectrodes (Au MEs) modified with ACNEs was significantly improved, exhibiting a 30-fold enhancement compared to Au MEs. This improved performance suggests that ACNE functionalization holds great promise for developing micro-biosensors with enhanced sensitivity and stability for detecting small molecules.

Optimization of Four Different Rosemary Extraction Techniques Using Plackett-Burman Design and Comparison of Their Antioxidant Compounds.

Rosemary has many medicinal and therapeutic properties and therefore it is important to study how to maximize the recovery of its bioactive compounds. In the present study, four different extraction techniques were used, namely stirring extraction (STE), pulsed electric field-assisted extraction (PEF), ultrasound probe-assisted extraction (UPAE), and ultrasound bath-assisted extraction (UBAE). First, some primary experiments were carried out in order to optimize each technique individually through the Plackett-Burman design. Then, each technique was applied under optimal conditions and the results were compared with each other. The optimal total polyphenol content (TPC) of STE is ~19 mg gallic acid equivalents per gram of dry weight (dw), while the antioxidant activity of the extract is 162 µmol ascorbic acid equivalents (AAEs) per gram of dw via FRAP and ~110 µmol AAE per gram of dw via DPPH. As for PEF, the optimal TPC is ~12 mg GAE/g dw, and the FRAP and DPPH values are ~102 and ~70 µmol AAE per gram of dw, respectively. When it comes to UPAE, the optimal TPC is ~16 mg GAE/g dw and the antioxidant capacity of the extract is ~128 µmol AAE/g dw through FRAP and ~98 µmol AAE/g dw through DPPH. UBAE optimal extract yielded ~17 mg GAE/g dw TPC, ~146 µmol AAE/g dw for FRAP, and ~143 µmol AAE/g dw for DPPH. The highest flavonoid content (~6.5 mg rutin equivalent/g dw) and DPPH (~143 µmol ascorbic acid equivalent/g dw) is obtained through UBAE. UPAE has been shown to be more efficient in recovering ascorbic acid (~20 mg/g dw). Additionally, the chlorophyll-to-carotenoid ratios of UPAE and UBAE were 2.98 and 2.96, respectively, indicating that the extracts had a generally positive impact on health. Considering the environmental impact of each extraction technique but also which antioxidant factor needs to be maximized, the most suitable extraction technique will be chosen.

Comparative analysis of nutrient composition and antioxidant activity in three dragon fruit cultivars.

Dragon fruit has significant economic value in many countries due to has excellent nutritional content, health advantages, and adaptability to different climates, making it an important crop in the global fruit industry. This study aimed to gather comprehensive nutritional data on three dragon fruit cultivars by analysing the levels of micronutrients, fibre, carbohydrates, antioxidants, vitamins, and minerals in their pulps. Uniform dragon fruit samples underwent thorough analysis for proximate composition, mineral content, pigments, antioxidants, and vitamin C, with statistical methods used to assess significant differences among the parameters studied. The proximate composition analysis revealed significant differences among the three dragon fruit cultivars. Among the proximate components, protein (0.40 ± 0.02 g/100 g), moisture (91.33 ± 0.88%), crude fibre (0.32 ± 0.07 g/100 g), and ash (1.27 ± 0.09 g/100 g) were more abundant in Hylocereus costaricensis than in Hylocereus undatus and Hylocereus megalanthus. On the other hand, Hylocereus undatus had higher carbohydrate (17.02 ± 0.63 g/100 g) and energy (69.74 ± 2.44 kcal/100 g) contents. K (7.23 ± 0.35 mg/100 g), Ca (1.61 ± 0.13 mg/100 g), Fe (1.84 ± 0.05 mg/100 g), and Zn (0.37 ± 0.034 mg/100 g) are highly abundant in H. costaricensis. Additionally, Hylocereus costaricensis had the highest anthocyanin content (120.15 ± 3.29 mg/g FW) and total carotenoid content (72.51 ± 1.62 mg/g FW), along with the highest vitamin C content (8.92 ± 0.13 mg/g FW) and total soluble phenolic content (572.48 ± 20.77 mg/100 g). Its remarkable antioxidant activity was further highlighted by the lowest SC50 value (13.50 ± 0.4 mg/mL) for its DPPH radical scavenging capacity. The total soluble sugar content was highest in Hylocereus megalanthus (8.72 ± 0.30 g/100 g FW). Hierarchical clustering analysis revealed distinct trait and genotype associations; among the studied cultivars, Hylocereus costaricensis demonstrated superior performance across multiple traits. Correlation analysis indicated significant positive correlations among several traits, while principal component analysis highlighted the contribution of each trait to overall variance, with PC1 explaining 73.95% of the total variance. This study highlights the nutritional variations among dragon fruit cultivars, with Hylocereus costaricensis showing superior performance, guiding dietary planning and functional food development.

Development of flavored kombuchas with Amazonian fruits: bioactive compounds evaluation and antioxidant capacity.

Using Amazonian fruits to flavor kombuchas is a promising proposal, as it adds nutritional value to the drink. This work sought to develop kombucha flavored with Amazonian fruits and evaluate the bioactive compounds and antioxidant capacity of the formulations. Three kombucha formulations were prepared using green tea (Camellia sinensis) and three Amazonian fruits: cupuassu (Theobroma grandiflorum), tapereba (Spondias lutea L.) and bacuri (Platonia insignis). Kombucha fermentations were evaluated before and after the insertion of nectars through the analysis of phenolic compounds, vitamin C and antioxidant capacity. Analyzes of pH, total sugars, acetic acid, ethanol, and microbiological characterization of final formulations were also carried out. For the first fermentation, were found values of phenolic compounds and antioxidant capacity of 30.60 ± 0.93 mg EAG/L and 295.02 ± 5.59 µmol ET/mL, and the formulation with tapereba showed the highest values for total phenolic compounds (34.92 ± 12.25 mg EAG/L), antioxidant capacity (320.57 ± 9.53 µmol ET/mL) and vitamin C (198.25 mg/100g). Thus, the formulations developed had a crucial nutritional appeal to stimulate consumption by the population, in addition to enabling the valorization and addition of commercial value to the Amazonian fruits used.