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Sweet potato has played an important role in human diets for centuries. Sweet potato is an excellent source of nutrients and natural health-promoting chemicals such as carotenoids, vitamin C, and polyphenols. In this article, we selected forty-eight sweet potato cultivars to evaluate the contents of proximate compositions, phytochemicals, and total antioxidative capacity (TAC). In addition, the sensory taste test was conducted as well. The concentrations of chemical constituents varied significantly among the 48 cultivars. The starch content ranged from 10.58% to 28.08%. The protein concentration was between 2.00% and 12.16%. A noticeable variability was found in vitamin C (8.17–66.09 mg·100 g−1), total polyphenols (0.32–13.82 µg·g−1), and carotenoids (0.22–559.70 µg·g−1). 3,5-dicaffeoylquinic acid was the dominant phenolic acid derivative in all varieties, followed by chlorogenic acid. The content ranges of 3,5-dicaffeoylquinic acid and chlorogenic acid were 0.41–92.18 µg·100 g−1 and 1.59–63.98 µg·100 g−1, respectively. Remarkable DPPH (0.19–0.59 µg·g−1) and ABTS+ (0.19–1.42 µg·g−1) antioxidant activities were also observed in these sweet potatoes. TAC was related to vitamin C, carotenoids, total polyphenols, and caffeic acid derivatives. The purple flesh cultivars, especially Mianzishu-9, Jiheishu-1, and Qianshu-18-5-1, rich in protein, starch, and antioxidants, had immense potential to improve malnutrition and hidden hunger. The dark orange flesh cultivars Hongxiangjiao and Ziyunhongxinshu performed best in sensory taste evaluation, but the nutrients and antioxidant effects were ordinary. These cultivars were suitable for enriching the human food systems. [ABSTRACT FROM AUTHOR]

Citrus fruits, regarded as a prominent fruit crop, are cultivated extensively around the globe and orange (Citrus sinensis L.) is a widely cultivated popular member of the citrus family. Dried oranges have gained recognition as a healthy snack option among consumers and worldwide markets due to the absence of additional ingredients such as sugar and chemicals, whilst yet containing significant natural beneficial components. The drying method is very intriguing due to its ability to facilitate the efficient production, packaging, storage, and transportation of dried oranges at a cost-effective price. In this study, the effects of microwave pretreatment (Mpt) (90 W, 30 min) on hot air drying (HTAD-MW) (60, 70, and 80°C) were investigated, along with the effects on the drying kinetics, rehydration capacity, and quality properties of the orange snack including phenolic compounds (vanillic acid, gallic acid, epicatechin, hesperidin, naringenin, chlorogenic acid, sinapic acid, and o-coumaric acid), antioxidant capacities (with DPPH, FRAP, and CUPRAC methods), and ascorbic acid contents. For modeling the kinetics of orange snack drying in all tests, logarithmic, Wang and Singh's, diffusion approach, two term, and Wang and Sing's models performed best. Hot air drying (HTAD) at 70°C applied orange snacks showed the lowest △E ∗ ab value, and the color values were close to those of fresh orange slices. The levels of total and individual phenolics, antioxidant capacity (AC), and ascorbic acid (AA) in dried orange snacks were found to be significantly lower (p < 0.05) than in the fresh orange slices. Results also showed that HTAD-MW-applied orange snacks contained more total phenolic (TP) content, individual phenolic content, and AC but lower AA than HTAD-applied samples. The highest amount of phenolic compound was hesperidin for fresh and dried orange snacks. The method that best preserves the TP content and AC of dried orange snacks was found at the drying condition of HTAD-MW at 60°C. As a conclusion, it was suggested that the use of microwave and hot air combination is a promising method to introduce a new functional healthy snack to the dried product market with high quality. [ABSTRACT FROM AUTHOR]

Peroxidation during organism growth and development might have catastrophic implications. It is critical to further investigate the antioxidant potential of plant anthocyanins. In this study, anthocyanins from Eleutherococcus brachypus fruits (EBF) were extracted by an ultrasonic-assisted method. The anthocyanins were then tested for stability under various storage conditions. Based on single-factor combination with response surface optimization, the best ethanol concentration for anthocyanin extraction was 75%, the ideal ultrasonic irradiation power was 160 W, the liquid-to-solid ratio was 10.18 mL/g, and the maximum anthocyanin yield was 1.86 mg/g. Anthocyanins are readily degraded by bright light and remain stable under acidic storage conditions (pH 3.0) and at temperatures below 60°C. The inhibition rates of anthocyanins against ABTS and DPPH radicals were 54.59% and 48.70%, respectively, using vitamin C (Vc) as a positive control. The data cited above make it clear that anthocyanins may act as natural antioxidants. In addition, this research provides a sound theoretical foundation for the creation of natural green antioxidants. [ABSTRACT FROM AUTHOR]

The utilization of natural preservatives presents a promising avenue for mitigating the spoilage of fresh-cut fruits and vegetables induced by microorganisms, enzymatic browning, and water loss. We have developed an innovative method for preserving fresh-cut green peppers using the combined effects of ε-polylysine (ε-PL) and p-Coumaric acid (p-CA). Through concentration screening experiments, we determined that the optimal concentrations of ε-PL and p-CA were 25 mg/L and 10 mg/L, respectively (ε-p-CA). Treatment with ε-p-CA significantly improved the quality of fresh-cut green peppers. It effectively reduced hardness and weight loss, preserving the texture and appearance of the peppers. Furthermore, ε-p-CA treatment delayed the increase in respiratory rate, electrolyte leakage, and ethylene production, thereby maintaining the structural integrity. Meanwhile, ε-p-CA treatment effectively inhibited the malondialdehyde (MDA) content increase and maintained DPPH radical scavenging activity. The microbial analysis demonstrated the ε-p-CA-treated peppers also showed lower total bacterial, mold, and yeast counts, which prolonged the freshness of fresh-cut peppers. In addition, ε-p-CA treatment improved the retention of phenolics and vitamin C without significantly affecting the color and soluble sugar content of green peppers. Overall, the ε-p-CA treatment showed promise as a natural preservative for extending the shelf life of fresh-cut green peppers. [ABSTRACT FROM AUTHOR]

This study evaluated the antioxidant, anticancer, and neuroprotective activities of germinated shoots (cotyledon and true leaves) of wild plants and measured their total phenol, flavonoid, quercetin, and vitamin C contents. The ethanol extract of Geum aleppicum (GA) showed high DPPH and ABTS radical scavenging activities. GA treatment also significantly increased cell viability against hydrogen peroxide-induced oxidative stress in SH-SY5Y neuronal cells, indicating that GA had antioxidant and neuroprotective properties. In AGS gastric cancer cells, the cotyledon of Pinus densiflora (PD1) and the true leaves of Chamaecyparis obtusa (CHA2) significantly inhibited cell proliferation, showing that PD1 and CHA2 elicited anticancer effect. The total phenol content was the highest in the shoots of GA, and the total flavonoid content was the highest in the shoots of true leaves of P. densiflora. The quercetin and vitamin C contents were the highest in the CHA2 and the cotyledon of GA, respectively. In conclusion, this study suggested the antioxidant, anticancer, and neuroprotective activities of the germinated shoots of wild plants and their high total phenol, flavonoid, quercetin, and vitamin C contents. These findings were noteworthy in the case of the germinated shoot of GA and provided a basis for studying functional forestry income resources. Practical Applications. Our results demonstrated that GA exerts strong DPPH and ABTS radical scavenging activities. It also plays a neuroprotective role in oxidative stress-induced cell damage. These effects can be linked to their polyphenol and flavonoid contents in the extract. Moreover, PD1 treatment has inhibitory effect on gastric tumor cells growth and exhibited an effective ∙OH radical scavenging property. These findings indicated that germinated shoot extracts have potential for development of functional food with therapeutic applications. [ABSTRACT FROM AUTHOR]

Low-pressure plasma (LPP) treatment was implemented as a nonthermal technology to preserve the organoleptic and nutritional qualities of lyophilized lemon slices. Effects of LPP treatment on the basic quality and flavor characteristics of lyophilized lemon slices stored for 7 d were evaluated. Fresh lyophilized lemon slices were prepared as a reference. The total titratable acids and sugars were in the range of 1.00∼1.11 mg/mL and 190.21∼197.37 mg/mL. The total phenolic content and Vc gradually decreased during storage from 1.74 to 1.33 mg/mL and 0.53 to 0.31 mg/mL. LPP had minor effects on total sugars and total titrate acids but prevented the storage losses of vitamin C (Vc) and phenols. A total of 35 volatile organic compounds were identified with C10 monoterpenoids being the major compounds. C6-C9 aldehydes corresponding to a green grassy aroma gradually decreased with increasing storage time. The gallery plot confirmed the different compositions of volatile organic compounds in LPP-treated samples. LPP-treated lemon slices had a higher content of preferred aromatic substances (terpinen-4-ol, α-terpineol, α-terpinene, and limonene) with a citrus-like flavor. These results demonstrated the positive effect of LPP treatment on retaining the flavor characteristics of lemon slices. [ABSTRACT FROM AUTHOR]

Ellagic acid (EA) is a bioactive polyphenol compound with numerous biological activities, such as anti-inflammatory, antiestrogenic, antioxidant, and anticancer activities. In this research, we investigated the effect of postharvest tomato fruits with EA treatment. Our results showed that at 25°C for 20 days, compared to a control group, the weight loss rate, titratable acidity, and soluble solid concentration of tomato fruits treated with 50 μM EA were lower. The content of soluble protein in the EA-treated group was approximately 1.65 times higher than in the control group, and EA treatment greatly inhibited the changes in lycopene and vitamin C content. Moreover, EA treatment reduced malondialdehyde content, electrolyte leakage, and the production of reactive oxygen species. Furthermore, EA treatment upregulated the expression of antioxidant-related genes and induced the activities of the antioxidant enzyme. In summary, our results showed that EA could retard senescence and preserve the quality characteristics of harvested tomato fruits via enhancing the antioxidant responses. [ABSTRACT FROM AUTHOR]

Strawberry fruit is one of people's favorite fruits. It has high nutritional value and health care effects. Strawberries lose their edible value quickly after being picked because of their thin skin, which is easily damaged. In order to find a method to maintain the quality of strawberries, the effects of resveratrol treatment on the nutritional quality and antioxidant metabolism of strawberry fruit were studied. The result indicated that 100 μM resveratrol was the optimal concentration to delay the occurrence of decay. Strawberry fruit treated with resveratrol delayed the decrease in firmness, total soluble solids (TSS), total phenolics content (TPC), total flavonoid content (TFC), vitamin C (Vc) content,1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), and 2,2′‐azino‐bis (3‐ethylbezothi‐ azot‐hiazoline‐6‐sulfonic acid) (ABTS) radical scavenging capacities. The malondialdehyde (MDA) content, hydrogen peroxide (H2O2) content, and superoxide anion (O2•−) production of control fruit were significantly higher than those of treated fruit. Strawberry fruit treated with resveratrol also increased the activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) during storage. Therefore, resveratrol has been proved to effectively improve the nutritional quality and antioxidant properties of strawberry fruit. Practical applications: Strawberry fruit is rich in nutrients, which is beneficial to human health. But strawberry fruit has high water content and soft tissue, which is easy to be damaged and decayed. Therefore, it is particularly important to find a way to maintain strawberry fruit quality. In this study, resveratrol has good antioxidant, health care, and antibacterial properties. Resveratrol treatment can maintain the nutritional quality of strawberry fruit and can be used as an effective method for strawberry fruit preservation. [ABSTRACT FROM AUTHOR]

In this study, the interaction between lotus rhizome polyphenol oxidase (PPO) and ascorbic acid (AA) was discussed from the aspects of inhibitory activity, thermodynamics, and conformation. Results showed that PPO was purified from lotus rhizome by DEAE‐52 anion exchange chromatography and Sephadex G‐100 gel filtration chromatography, with its optimum substrate being determined as pyrogallic acid. Spectrophotometric and polarographic assays demonstrated that AA exhibited strong inhibitory activity against PPO. Thermodynamics, fluorescence, and circular dichroism spectral analysis showed that hydrophobic interactions caused the formation of AA–PPO complex, leading to the remarkable fluorescence quenching and conformational change of PPO. Atomic force microscopic analysis revealed that binding to AA induced significant changes in the surface morphology and molecular aggregation of PPO molecules. In this study, the interaction mechanism between PPO and AA was proposed for the first time, which provided a theoretical basis for AA to inhibit lotus rhizome browning. Practical applications: Lotus rhizome, an aquatic vegetable, is prone to enzymatic browning in processing operations, which leads to a decrease in market value and economic loss. At present, ascorbic acid (AA) is widely used in industries as an excellent antioxidant because of its good antibrowning effect and relatively low cost. However, the interaction between the enzymatic browning‐related polyphenol oxidase (PPO) from lotus rhizome and ascorbic acid has not been clearly studied. Understanding the mechanism of inhibiting PPO will help to prevent vegetable browning, especially fresh‐cut products. The inhibitory effect of AA on PPO in lotus rhizome favors simultaneous use with other types of PPO inhibitors because of their likely synergistic effects. [ABSTRACT FROM AUTHOR]

Nonalcoholic Palm Nectar from Cocos nucifera (NPNC), a bio‐refresher obtained from the juvenile inflorescence of coconut palm; is prominent as a nutritional health drink. The aim of this study was to investigate the nutritional and medicinal properties of NPNC and its products; sugar (NPNCS) and honey (NPNCH). The collected samples were subjected to physicochemical evaluations such as pH, Titrable Acidity, Total Soluble Solids, and Ash value, using standard techniques. The analysis revealed the suitability of NPNC as a natural health drink over conventionally available beverage. The elemental compositions of the samples were determined by using Inductive Coupled Plasma—Atomic Emission Spectrometry and demonstrated that NPNCH is enriched with iron and NPNCS with calcium. Vitamin C present in the samples was determined by using 2,6‐Dichlorophenol indophenol redox titration method. Hydrolysable polyphenols, tannins, and flavonoids are determined by Folin‐Ciocalteu, by Folin‐Denis's technique and by aluminium chloride colorimetric methods, respectively. In NPNC, the dominance of Vitamin C as antioxidant is observed. Diuretic activity of samples was determined by Lipschitz method, and the results revealed that NPNC exhibited significant diuretic activity, comparable with furosemide. Immunomodulatory activities of the samples were evaluated by using indirect hemagglutination test and by using delayed type hypersensitivity (DTH) response. NPNC, NPNCS, and NPNCH exhibited stimulatory effect on humoral and cell‐mediated immunity, which is comparable with that of standard immunomodulator levamizole. Subacute toxicity studies of selected samples were done in Wistar rats and the results proved the boicompatibility of the samples without systemic toxic effects. Practical applications: The use of commercially available carbonated beverages and energy drinks in young adults are associated with negative health outcomes with increased incidence of diabetes, sleep disturbances, and dental problems. Even though, such complications are there, the energy drink industries have grown dramatically accounting for major percentage of market sale. Researchers are in search for natural health drinks with some medicinal value to avoid the negative impact on consumers' health. Nonalcoholic Palm Nectar from Cocos nucifera (NPNC) is considered as zero alcoholic natural health drink. The focus of this study is to reveal the potential medicinal properties of NPNC and its products; honey (NPNCH) and sugar (NPNCS). If the nutritional and medicinal values of the selected preparations from natural sources can be proved with scientific evidence, its ability to beat commercially available carbonated beverages and energy drinks with negative health consequences may get widespread acceptance. [ABSTRACT FROM AUTHOR]

This study investigated the anti‐inflammatory and antioxidant effects of hydroalcoholic extracts of mango peel and pulp on oxidative damage in a naproxen‐induced gastric injury rat model. The extracts were assessed for antioxidant activity (ABTS and FRAP methods), and the phenolic profile was investigated with UPLC‐QToF‐MSE. Gastric damage was evaluated in vivo by assessing the membrane lipid peroxidation (malondialdehyde (MDA) content), myeloperoxidase (MPO) enzyme activity, and glutathione (GSH) content. Mango peel and pulp contained high contents of bioactive compounds, particularly phenolics (69.50–5.287.70 mg gallic acid equivalents/100 g), carotenoids (651.30–665.50 μg/100 g), and vitamin C (21.59–108.19 mg/100 g). UPLC‐QToF‐MSE analysis identified 17 phenol compounds, including gallotannins, glycosylated flavonoids, and xanthone. The hydroalcoholic extracts of mango peel and pulp (LPe and LPu, respectively) significantly reduced the MPO activity and MDA content. In addition to preventing naproxen‐induced GSH decline, LPe (30 mg/kg) and LPu (10 mg/kg) restored its content to normal levels. LPe and LPu neutralized the oxidizing agents triggered by naproxen and reduced the severity of gastric lesions owing to their antioxidant properties. [ABSTRACT FROM AUTHOR]

Tyrosinase (polyphenol oxidase) is the key enzyme of enzymatic browning in fruits and vegetables. In this research, the impact of ascorbic acid on tyrosinase and its anti‐browning effect on fresh‐cut Fuji apple were investigated. Ascorbic acid had a dual effect on tyrosinase with a half inhibitory concentration (IC50) of 13.40 ± 0.05 µM. Fluorescence assay demonstrated that ascorbic acid interacted with tyrosinase in a dynamic contaction caused by Förster's resonance energy transfer (FRET) and induced a conformational change of the enzyme. Thermodynamic analysis, copper interaction, and molecular docking further confirmed that ascorbic acid could chelate the copper ions located in active center and interact with amino acid residues of tyrosinase via hydrophobic interaction. In addition, ascorbic acid prevented the browning of fresh‐cut apples by increasing APX activity and inhibiting PPO and POD activities which reduce the oxidation of total phenolics and flavonoids. Practical applications: The present study demonstrated that ascorbic acid had a strong inhibitory activity against tyrosinase (IC50 = 13.40 ± 0.05 µM) and anti‐browning activity against fresh‐cut Fuji apple. It could delay the browning degree of apple juice, increase APX activity, inhibit PPO and POD activities, and reduce the oxidation of total phenolics and flavonoids. These findings provided a basis for the feasible application of ascorbic acid on the preservation of fruits. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effects of Penicillium expansum (P. expansum) infection on the quality and flavor of Jinmi (JM) and Jinyan (JY) kiwifruit. Kiwifruit were inoculated with P. expansum and stored at 0 ± 1°C, and the changes in quality indicators and volatile substances (VCs) at different stages of disease were determined. Results showed that in wound‐inoculated kiwifruit, the soluble solid content (SSC) increased. Conversely, their titratable acidity and vitamin C (VC) content, firmness, lightness, and saturation decreased. The taste‐related parameters and nutritional value of kiwifruit declined after infection. VCs such as ethanol, 3‐methyl‐1‐butanol, and 2‐methylisoborneol were detected only in the diseased fruit and gradually increased as the disease aggravated, suggesting that they may be the main sources of odor during P. expansum infection. Therefore, VCs detection can be used to determine possible P. expansum infection, as well as the degree of infection in kiwifruit. Practical applications: In practical application, we can use the results of this study to determine possible Penicillium expansum infection, as well as the degree of infection in kiwifruit according to the indicators such as volatile substances. Kiwifruit enterprises can use the nondestructive detection model established in this study to screen out the kiwifruit infected with P. expansum more efficiently, quickly, and accurately, in order to prevent harm to the health of consumers. [ABSTRACT FROM AUTHOR]