Exploration of Raw Pigmented-Fleshed Sweet Potatoes Volatile Organic Compounds and the Precursors.

Sweet potato provides rich nutrients and bioactive substances for the human diet. In this study, the volatile organic compounds of five pigmented-fleshed sweet potato cultivars were determined, the characteristic aroma compounds were screened, and a correlation analysis was carried out with the aroma precursors. In total, 66 volatile organic compounds were identified. Terpenoids and aldehydes were the main volatile compounds, accounting for 59% and 17%, respectively. Fifteen compounds, including seven aldehydes, six terpenes, one furan, and phenol, were identified as key aromatic compounds for sweet potato using relative odor activity values (ROAVs) and contributed to flower, sweet, and fat flavors. The OR sample exhibited a significant presence of trans-ß-Ionone, while the Y sample showed high levels of benzaldehyde. Starch, soluble sugars, 20 amino acids, and 25 fatty acids were detected as volatile compounds precursors. Among them, total starch (57.2%), phenylalanine (126.82 ± 0.02 g/g), and fatty acids (6.45 µg/mg) were all most abundant in Y, and LY contained the most soluble sugar (14.65%). The results of the correlation analysis revealed the significant correlations were identified between seven carotenoids and trans-ß-Ionone, soluble sugar and nerol, two fatty acids and hexanal, phenylalanine and 10 fatty acids with benzaldehyde, respectively. In general, terpenoids and aldehydes were identified as the main key aromatic compounds in sweet potatoes, and carotenoids had more influence on the aroma of OR than other cultivars. Soluble sugars, amino acids, and fatty acids probably serve as important precursors for some key aroma compounds in sweet potatoes. These findings provide valuable insights for the formation of sweet potato aroma.

Preparation of Steamed Purple Sweet Potato-Based Films Containing Mandarin Essential Oil for Smart Packaging.

Anthocyanin-rich steamed purple sweet potato (SPSP) is a suitable raw material to produce smart packaging films. However, the application of SPSP-based films is restricted by the low antimicrobial activity of anthocyanins. In this study, SPSP-based smart packaging films were produced by adding mandarin essential oil (MEO) as an antimicrobial agent. The impact of MEO content (3%, 6%, and 9%) on the structures, properties, and application of SPSP-based films was measured. The results showed that MEO created several pores within films and reduced the hydrogen bonding system and crystallinity of films. The dark purple color of the SPSP films was almost unchanged by MEO. MEO significantly decreased the light transmittance, water vapor permeability, and tensile strength of the films, but remarkably increased the oxygen permeability, thermal stability, and antioxidant and antimicrobial properties of the films. The SPSP-MEO films showed intuitive color changes at different acid-base conditions. The purple-colored SPSP-MEO films turned blue when chilled shrimp and pork were not fresh. The MEO content greatly influenced the structures, physical properties, and antioxidant and antimicrobial activities of the films. However, the MEO content had no impact on the color change ability of the films. The results suggested that SPSP-MEO films have potential in the smart packaging of protein-rich foods.

Relationship between sensory attributes and instrumental texture properties in meat analog patty system substituted with sweet potato stem.

BACKGROUND: Understanding the relationship between perceived sensory attributes and measurable instrumental properties is crucial for replicating the distinct textures of meat in plant-based meat analogs. In this study, plant-based patties composed of textured vegetable protein (TVP) and 10%, 20% and 30% TVPs were substituted with fibers from sweet potato stem (SPS), and their instrumental texture and sensory properties were evaluated. RESULTS: Samples with 20% SPS showed hardness, cohesiveness and chewiness, which are the mechanical indicators most similar to those of meat. A descriptive sensory analysis by ten trained participants indicated that the SPS-supplemented meat analog patties exhibited characteristics similar to pork patties in terms of firmness, toughness, cohesiveness and smoothness compared to the TVP-only sample. A strong positive correlation between instrumental hardness and sensory firmness was observed (P < 0.01); however, cohesiveness, springiness and chewiness did not show any correlation between instrumental and sensory analyses. Warner-Bratzler shear force (WBSF) values showed positive correlations with sensory cohesiveness, chewiness, toughness, fibrousness, moistness, firmness and springiness (P < 0.05). CONCLUSION: The results demonstrated the feasibility of physically treated fibers from SPS as a partial substitute for TVP in developing meat analogs. Additionally, this study suggested that instrumental hardness and WBSF measurements can be sound parameters for representing sensory texture characteristics while further developing plant-based meat analogs. © 2024 Society of Chemical Industry.

Effects of different pretreatment methods on the degree of substitution, structure, and physicochemical properties of synthesized malic acid sweet potato starch ester.

BACKGROUND: The preparation of malic acid starch ester (MSE) is mostly carried out using a high temperature method, but there are problems such as high energy consumption, long preparation time, and uneven heating. Microwave technology can be used to overcome these limitations. The semi-crystalline structure of starch granules hinders the modifier's access to the matrix, thus limiting the esterification reaction. Physical techniques can act on the interior of the starch to create a number of active sites, thereby facilitating the reaction of the starch with esterification reagents. Therefore, this study investigated the effect of starch pretreatment by microwave, heat-moisture, and ultrasonic techniques on the degree of substitution (DS), structure, and physicochemical properties of MSE synthesized by the microwave method. RESULTS: The DS of MSE was increased after pretreatments. The modified starch obtained by different pretreatment methods did not show new characteristic peaks, while the MSE synthesized showed new absorption peaks near 1735 cm-1. The granular structure and morphology of the modified starch obtained by microwave and heat-moisture pretreatment were gelatinized and aggregated, while some of the starch particles of the modified starch obtained by ultrasonic pretreatment appeared pore-sized. The relative crystallinity and gelatinization enthalpy of the MSE were reduced, but the crystallization pattern remained as A-type. CONCLUSION: Overall, the results suggest that various pretreatment methods can enhance the DS of MSE by disrupting the structure of starch. The findings of this study provide theoretical support for improving the DS of esterified starch. © 2024 Society of Chemical Industry.

In vitro digestion and colonic fermentation characteristics of media-milled purple sweet potato particle-stabilized Pickering emulsions.

BACKGROUND: Pickering emulsions stabilized by multicomponent particles have attracted increasing attention. Research on characterizing the digestion and health benefit effects of these emulsions in the human gastrointestinal tract are quite limited. This work aims to reveal the digestive characteristics of media-milled purple sweet potato particle-stabilized Pickering emulsions (PSPP-Es) during in vitro digestion and colonic fermentation. RESULTS: The media-milling process improved the in vitro digestibility and fermentability of PSPP-Es by reaching afree fatty acids release rate of 43.11 ± 4.61% after gastrointestinal digestion and total phenolic content release of 101.00 ± 1.44 µg gallic acid equivalents/mL after fermentation. In addition, PSPP-Es exhibited good antioxidative activity (2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assays), α-glucosidase inhibitory activity (half-maximal inhibitory concentration: 6.70%, v/v), and prebiotic effects, reaching a total short-chain fatty acids production of 9.90 ± 0.12 mol L-1, boosting the growth of Akkermansia, Bifidobacterium, and Blautia and inhibiting the growth of Escherichia-Shigella. CONCLUSIONS: These findings indicate that the media-milling process enhances the potential health benefits of purple sweet potato particle-stabilized Pickering emulsions, which is beneficial for their application as a bioactive component delivery system in food and pharmaceutical products. © 2024 Society of Chemical Industry.

Sweet potato yield and quality characteristics affected by different late-season irrigation levels.

BACKGROUND: Seasonal late-season water deficits negatively affect the yield and quality of sweet potatoes in northern China. However, the amount of late-season irrigation to achieve high yield and consistent quality storage root remains undetermined. We assessed the yield and some qualitative traits of sweet potatoes such as size, shape, skin/flesh colour and nutritional content, as influenced by five irrigation levels (T0: unirrigated control; T1: 33% ETc; T2: 75% ETc; T3: 100% ETc; and T4: 125% ETc). RESULTS: Late-season irrigation significantly increased yield and marketable yield. Yields for T2 and T3 were significantly higher than other treatments, whereas T2 had the highest Grade A rating in a 2-year test. The vertical length of storage roots gradually increased with an increase in irrigation level, whereas the maximum width remained unchanged. The proportion of long elliptic and elliptic storage roots also increased, whereas the proportion of ovate, obovate and round storage roots gradually decreased. The skin and flesh colours became more vivid as the level of irrigation increased, with the skin colour becoming redder and the flesh colour becoming more orange-yellow. The levels of carotenoids, vitamin C and soluble sugar were significantly higher in irrigated crops, with the highest vitamin C and soluble sugar levels in T2 and the highest carotenoid levels in T3 treatment. CONCLUSION: Taken together, these results demonstrate the potential of moderate irrigation in the late-season to improve both yield production and quality potential. The results are of great importance for improving the market value of sweet potatoes and increasing grower profits. © 2024 Society of Chemical Industry.

Advances in valorization of sweet potato peels: A comprehensive review on the nutritional compositions, phytochemical profiles, nutraceutical properties, and potential industrial applications.

During food production, food processing, and supply chain, large amounts of food byproducts are generated and thrown away as waste, which to a great extent brings about adverse consequences on the environment and economic development. The sweet potato (Ipomoea batatas L.) is cultivated and consumed in many countries. Sweet potato peels (SPPs) are the main byproducts generated by the tuber processing. These residues contain abundant nutrition elements, bioactive compounds, and other high value-added substances; therefore, the reutilization of SPP holds significance in improving their overall added value. SPPs contain abundant phenolic compounds and carotenoids, which might contribute significantly to their nutraceutical properties, including antioxidant, antimicrobial, anticancer, prebiotic, anti-inflammatory, wound-healing, and lipid-lowering effects. It has been demonstrated that SPP could be promisingly revalorized into food industry, including: (1) applications in diverse food products; (2) applications in food packaging; and (3) applications in the recovery of pectin and cellulose nanocrystals. Furthermore, SPP could be used as promising feedstocks for the bioconversion of diverse value-added bioproducts through biological processing.

Genetic diversity assessment and genome-wide association study reveal candidate genes associated with component traits in sweet potato (Ipomoea batatas (L.) Lam).

The Korean sweet potatoes were bred by various cultivars introduced from Japanese, American, Porto Rico, China, and Burundi. This issue enriched their genetic diversity but also resulted in a mixture of cultivars. For genotyping, we collected and sequenced 66 sweet potato germplasms from different localities around Korea, including 36 modern cultivars, 5 local cultivars, and 25 foreign cultivars. This identified 447.6 million trimmed reads and 324.8 million mapping reads and provided 39,424 single nucleotide polymorphisms (SNPs) markers. Phylogenetic clustering and population structure analysis distinctly classified these germplasms into 5 genetic groups, group 1, group 2, group 3, group 4, and group 5, containing 20, 15, 10, 7, and 14 accessions, respectively. Sixty-three significant SNPs were selected by genome-wide association for sugar composition-related traits (fructose, glucose, and total sugars), total starch, amylose content, and total carotenoid of the storage root. A total of 37 candidate genes encompassing these significant SNPs were identified, among which, 7 genes were annotated to involve in sugar and starch metabolism, including galactose metabolism (itf04g30630), starch and sucrose metabolism (itf03g13270, itf15g09320), carbohydrate metabolism (itf14g10250), carbohydrate and amino acid metabolism (itf12g19270), and amino sugar and nucleotide sugar metabolism (itf03g21950, itf15g04880). This results indicated that sugar and starch are important characteristics to determine the genetic diversity of sweet potatoes. These findings not only illustrate the importance of component traits to genotyping sweet potatoes but also explain an important reason resulting in genetic diversity of sweet potato.

Effect of potassium intake on cadmium transporters and root cell wall biosynthesis in sweet potato.

Large areas of farmland soil in southern China are deficient in potassium (K) and are contaminated with cadmium (Cd). Previously, we suggested that the K supplementation could reduce Cd accumulation in sweet potatoes (Ipomoea batatas (L.) Lam). In the present study, we investigated the underlying physiological and molecular mechanisms. A hydroponic experiment with different K and Cd treatments was performed to compare the transcriptome profile and the cell wall structure in the roots of sweet potato using RNA sequencing, Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The results showed that K supply inhibits the expressions of IRT1 and YSL3, which are responsible for root Cd uptake under Cd exposure. Furthermore, the expressions of COPT5 and Nramp3 were downregulated by K, which increased Cd retention in the root vacuoles. The upregulation of POD, CAD, INT1 and SUS by K contributed to lignin and cellulose biosynthesis and thickening of root xylem cell wall, which further reduced Cd translocation to the shoot. In addition, K affected the expressions of LHT, ACS, TPS and TPP associated with the production of ethylene and trehalose, which involved in plant resistance to Cd toxicity. In general, K application could decrease the uptake and translocation of Cd in sweet potatoes by regulating the expression of genes associated with Cd transporters and root cell wall components.

Extraction, purification, structural characterization, and hepatoprotective effect of the polysaccharide from purple sweet potato.

BACKGROUND: Purple sweet potato Ipomoea batatas (L.) has long been used as a medicine and a food. It contains various bioactive substances such as polysaccharides, anthocyanins, and flavonoids. Purple sweet potato polysaccharides are known to have anti-oxidant, anti-tumor, and immunomodulatory functions. Nevertheless, studies on the structural characterization of purple sweet potato polysaccharides and their ability to prevent non-alcoholic fatty liver disease (NAFLD) have rarely been reported. RESULTS: A novel polysaccharide (PSPP-A) was extracted and isolated from purple sweet potato, and its structural characteristics and preventive effects on NAFLD were investigated. The results indicated that PSPP-A was composed of l-rhamnose, d-arabinose, d-galactose, d-glucose, and d-glucuronic acid with molar ratios of 1.89:8.45:1.95:1.13:1. Its molecular weight was 2.63 × 103 kDa. Methylation and nuclear magnetic resonance (NMR) analysis indicated that the glycosidic linkages were →3)-α-L-Araf-(1→, α-L-Araf-(1→, →2,4)-α-L-Rhap-(1→, 4-O-Me-ß-D-GlcAp-(1→, →4)-α-D-Glcp-(1→, →4)-ß-D-Galp-(1→, and →6)-ß-D-Galp-(1→. Scanning electron microscopy (SEM) indicated that the structure of PSPP-A was irregular. Subsequently, the protective effect of PSPP-A on NAFLD was investigated. The results indicated that bodyweight, liver index, and triglyceride (TG), total cholesterol (TC), aspartate transaminase (AST), and alanine transaminase (ALT) content were significantly reduced by intervention of purple sweet potato polysaccharide-A (PSPP-A) compared with the - high-fat diet group. Liver histopathological analysis indicated that PSPP-A attenuated irregular hepatocyte patterns and excessive lipid vacuoles. CONCLUSIONS: The novel polysaccharide, PSPP-A, mainly contains arabinose, which has certain preventive effects on NAFLD. This study provides a theoretical basis for further elucidating the hepatoprotective effect of purple sweet potatoes as a functional food. © 2022 Society of Chemical Industry.

Sweet potato flour (Ipomoea batatas) as natural antioxidant on carcass yield and meat physicochemical characteristics of Creole chickens of Mexico and Cobb 500.

Antioxidants are considered functional additives against oxidative stress since they avoid nutritional decline in the meat. The main objective of the present study is to evaluate the effect of sweet potato flour (SPF) as a natural antioxidant on carcass yield and physicochemical characteristics of Creole chickens of Mexico (CChM) and Cobb 500 broilers. In total, 210 chickens (105 CChM and 105 Cobb 500 chickens) were randomly assigned to three treatments: 0, 500, and 1000 mg of SPF kg-1 of feed. The Cobb 500 chickens showed higher carcass yield (hot and cold), breast, and breast fillet, whereas the CChM had higher thigh yield (P ≤ 0.05). The yield on the previously mentioned variables was not affected by the inclusion levels of SPF. The initial pH differed because of the effect of the chicken's genotype and the addition of SPF, which was higher on Cobb 500 chicken and on those that were not supplemented with SPF. The birds' skin that consumed SPF presented higher yellowness after 24 h (P ≤ 0.05). CChM manifested a higher dry matter and protein content and a lower content of ash and fat (P ≤ 0.05). In conclusion, Cobb 500 chickens present a higher carcass yield and its components, in addition to a less acid pH; however, CChM offer a higher nutritional contribution, whereas the 500 and 1000 mg addition of SPF increases the skin yellowness, which makes it an alterorganic as a pigment on broiler chicken production.

Development of anthocyanin markers: gene mapping, genomic analysis and genetic diversity studies in Ipomoea species.

The anthocyanins are pigments responsible for a wide range of colours in plants, from blue, red and purple, play essential biological roles as well as their genes are evolutionarily conserved. Purple sweet potatoes have anthocyanins as the predominant colour, even though they are present in orange roots masked by carotenoids. Several studies have focused on molecular aspects of anthocyanin genes, mainly in wild Ipomoea species, although the structure and segregation analysis of those genes in sweet potato hexaploid species are still unknown. Based on an "exon-primed intron-crossing" (EPIC) approach, fourteen pairs of primers were designed, on five structural anthocyanin genes as candidates. The strategy exploits the Intron Length Polymorphism (ILP) from Candidate Genes (CG), resulting in 93% of successful markers giving scorable and reproducible alleles. The results allowed to define partial structure and sequence of the introns and exons from the selected CG, and to determine patterns of sequence variation. The evaluation of marker dosage and allelic segregations in an Ipomoea batatas (L.) Lam mapping population identified several alleles for linkage analysis. The study validated the utility of ILP-CG markers for genetic diversity and conservation applicability and a successful amplification gradient across wild Ipomoea species validated their transferability.

Extracting Total Anthocyanin from Purple Sweet Potato Using an Effective Ultrasound-Assisted Compound Enzymatic Extraction Technology.

This study aimed to develop an effective technique for extracting total anthocyanins from purple sweet potato (Mianzishu 9) (PSP9) by ultrasound-assisted compound enzymatic extraction (UAEE). Single-factor experiments, Plackett-Burman experimental design, and response surface methodology were utilized for optimizing extraction conditions, and the antioxidant activities were evaluated. Anthocyanins were also measured using an ultra-performance liquid chromatograph linked to a mass spectrometer (UPLC-MS). The maximum yield of total anthocyanins was 2.27 mg/g under the following conditions: the ethanol concentration was 78%, the material-to-liquid ratio was 1:15 g/mL, the enzyme ratio (cellulase: pectinase: papain) was 2:2:1 and its hydrolysis was at 41 °C, pH = 4.5, 1.5 h, the ultrasonication was at 48 °C and conducted twice for 20 min each time. In addition to higher yield, anthocyanins extracted from purple sweet potato by UAEE showed great ability to scavenge DPPH (IC50 of 0.089 µg/mL) and hydroxyl radicals (IC50 of 100.229 µg/mL). Five anthocyanins were found in the purple sweet potato extract from UAEE. Taken together, the ultrasound-assisted compound enzymatic method can rapidly and effectively extract anthocyanins with greater antioxidant capacity from purple sweet potato.

Total Phenolics and Anthocyanins Contents and Antioxidant Activity in Four Different Aerial Parts of Leafy Sweet Potato (Ipomoea batatas L.).

Leafy sweet potato (Ipomoea batatas L.) is an excellent source of nutritious greens and natural antioxidants, but reports on antioxidants content and activity at buds, leaves, petioles, and stems are scarce. Therefore, the total phenolics content (TPC), total anthocyanins content (TAC), and antioxidant activity (assessed by DPPH and ABTS radical scavenging activities and ferric reducing antioxidant power (FRAP)) were investigated in four aerial parts of 11 leafy sweet potato varieties. The results showed that varieties with pure green aerial parts, independently of the part analyzed, had higher TPC, FRAP, and ABTS radical scavenging activities. The green-purple varieties had a significantly higher TAC, while variety GS-17-22 had the highest TAC in apical buds and leaves, and variety Ziyang in petioles and stems. Among all parts, apical buds presented the highest TPC and antioxidant capacity, followed by leaves, petioles, and stems, while the highest TAC level was detected in leaves. The TPC was positively correlated with ABTS radical scavenging activity and FRAP in all parts studied, whereas the TAC was negatively correlated with DPPH radical scavenging activity. Collectively, the apical buds and leaves of sweet potato had the higher levels of nutritional values. These results would provide reference values for further breeding of leafy sweet potatoes.

Changes in Antioxidant Properties and Phenolics in Sweet Potatoes (Ipomoea batatas L.) Due to Heat Treatments.

Processing is one of the most crucial factors affecting polyphenol content in foods. Therefore, the study is aimed at the evaluation of heat treatment effects (microwaving, steaming, baking, and boiling) on the content of chlorogenic acids, total polyphenols, and antioxidant activity of three varieties of sweet potato with different flesh colors (Beauregard­orange-fleshed, O'Henry­white-fleshed, 414-purple­purple-fleshed). According to high performance liquid chromatography analysis, chlorogenic acid was the predominant chlorogenic acid in sweet potatoes. Obtained results also suggested the purple-fleshed variety (414-purple) had significantly (p < 0.05) higher total polyphenol content and thus the highest antioxidant activity. Heat treatment positively influenced the chlorogenic acid content, total polyphenols, and antioxidant activity of sweet potatoes. Among the used methods, steaming had the greatest effect on the chlorogenic acids and total polyphenols, while microwaved samples showed the highest antioxidant activity (DPPH). The content of chlorogenic acids and total polyphenols decreased in the order of steaming > baking > microwaving > boiling > raw. However, the individual varieties differed not only in the flesh color but also in the reaction to the used heat treatment methods. Spearman's correlation coefficient showed a strong correlation between chlorogenic acid and antioxidant activity.

Sizes, Components, Crystalline Structure, and Thermal Properties of Starches from Sweet Potato Varieties Originating from Different Countries.

Sweet potato is a root tuber crop and an important starch source. There are hundreds of sweet potato varieties planted widely in the world. Starches from varieties with different genotype types and originating from different countries have not been compared for their physicochemical properties. In the research, starches from 44 sweet potato varieties originating from 15 countries but planted in the same growing conditions were investigated for their physicochemical properties to reveal the similarities and differences in varieties. The results showed that the 44 starches had granule size (D[4,3]) from 8.01 to 15.30 µm. Starches had different iodine absorption properties with OD680 from 0.259 to 0.382 and OD620/550 from 1.142 to 1.237. The 44 starches had apparent amylose content from 19.2% to 29.2% and true amylose content from 14.2% to 20.2%. The starches exhibited A-, CA-, CC-, or CB-type X-ray diffraction patterns. The thermograms of 44 starches exhibited one-, two-, or three-peak curves, leading to a significantly different gelatinization temperature range from 13.1 to 29.2 °C. The significantly different starch properties divide the 44 sweet potato varieties into different groups due to their different genotype backgrounds. The research offers references for the utilization of sweet potato germplasm.

Comparative Metabolomic and Transcriptomic Analyses of Phytochemicals in Two Elite Sweet Potato Cultivars for Table Use.

To elucidate nutritional components in sweet potato cultivars for table use and to compare the phytochemicals of cultivars from different countries, 'Kokei No. 14' and 'Xinxiang' were selected. The physiological parameters and metabolites were determined using the colorimetric method and widely targeted metabolomics, respectively. Transcriptomic analysis was performed to explain the mechanism that resulted in phytochemical differences. 'Xinxiang' showed higher flavonoid and carotenoid contents. Metabolomics showed five upregulated flavonoids. Two essential amino acids (EAAs) and one conditionally essential amino acid (CEAA) were upregulated, whereas four EAAs and two CEAAs were downregulated. Unlike lipids, in which only one of thirty-nine was upregulated, nine of twenty-seven differentially accumulated phenolic acids were upregulated. Three of the eleven different alkaloids were upregulated. Similarly, eight organic acids were downregulated, with two upregulated. In addition, three of the seventeen different saccharides and alcohols were upregulated. In 'other metabolites,' unlike vitamin C, 6'-O-Glucosylaucubin and pantetheine were downregulated. The differentially accumulated metabolites were enriched to pathways of the biosynthesis of secondary metabolites, ABC transporters, and tyrosine metabolism, whereas the differentially expressed genes were mainly concentrated in the metabolic pathway, secondary metabolite biosynthesis, and transmembrane transport functions. These results will optimize the sweet potato market structure and enable a healthier diet for East Asian residents.

Natural Deep Eutectic Solvent-Based Microwave-Assisted Extraction of Total Flavonoid Compounds from Spent Sweet Potato (Ipomoea batatas L.) Leaves: Optimization and Antioxidant and Bacteriostatic Activity.

Natural deep eutectic solvents (NADESs) coupled with microwave-assisted extraction (MAE) were applied to extract total flavonoid compounds from spent sweet potato (Ipomoea batatas L.) leaves. In this study, ten different NADESs were successfully synthesized for the MAE. Based on single-factor experiments, the response surface methodology (RSM) was applied, and the microwave power, extraction temperature, extraction time, and solid−liquid ratio were further evaluated in order to optimize the yields of total flavonoid compounds. Besides, the extracts were recovered by macroporous resin for the biological activity detection of flavonoid compounds. As a result, NADES-2, synthesized by choline chloride and malic acid (molar ratio 1:2), exhibited the highest extraction yield. After that, the NADES-2-based MAE process was optimized and the optimal conditions were as follows: microwave power of 470 W, extraction temperature of 54 °C, extraction time of 21 min, and solid−liquid ratio of 70 mg/mL. The extraction yield (40.21 ± 0.23 mg rutin equivalents/g sweet potato leaves) of the model validation experiment was demonstrated to be in accordance with the predicted value (40.49 mg rutin equivalents/g sweet potato leaves). In addition, flavonoid compounds were efficiently recovered from NADES-extracts with a high recovery yield (>85%) using AB-8 macroporous resin. The bioactivity experiments in vitro confirmed that total flavonoid compounds had good DPPH and O2−· radical-scavenging activity, as well as inhibitory effects on E. coli, S. aureus, E. carotovora, and B. subtilis. In conclusion, this study provides a green and efficient method to extract flavonoid compounds from spent sweet potato leaves, providing technical support for the development and utilization of sweet potato leaves' waste.

Ameliorative Effect of Structurally Divergent Oleanane Triterpenoid, 3-Epifriedelinol from Ipomoea batatas against BPA-Induced Gonadotoxicity by Targeting PARP and NF-κB Signaling in Rats.

The pentacyclic triterpenoids (PTs) of plant origin are reputed to restrain prostate cancer (PCa) cell proliferation. This study aims to assess 3-epifriedelinol (EFD) isolated from aerial part of Ipomoea batatas against PCa and its potential mechanism, in vitro and in vivo. Molecular docking affirms good binding affinity of the compound with target proteins exhibiting binding energy of −7.9 Kcal/mol with BAX, −8.1 Kcal/mol (BCL-2), −1.9 Kcal/mol (NF-κB) and −8.5 Kcal/mol with P53. In the MTT assay, EFD treatment (3−50 µM) showed a significant (p < 0.05 and p < 0.01) dose and time dependent drop in the proliferative graph of DU145 and PC3, and an upsurge in apoptotic cell population. EFD displayed substantial IC50 against DU145 (32.32 ± 3.72 µM) and PC3 (35.22 ± 3.47 µM). According to Western blots, EFD administration significantly enhanced the cleavage of caspases and PARP, elevated BAX and P53 and decreased BCL-2 and NF-κB expression, thereby triggering apoptosis in PCa cells. When male Sprague Dawley rats were intoxicated with Bisphenol A (BPA), an apparent increase in prostate mass (0.478 ± 0.08 g) in comparison to control (0.385 ± 0.03 g) indicates prostatitis. Multidose treatment of EFD (10 mg/kg) significantly reduced prostate size (0.404 ± 0.05 g). EFD exhibited substantial curative potential in vivo, as hematological, hormonal and histopathological parameters have been significantly improved. Reduced peroxidation (TBARS), and suppression of inflammatory markers i.e., NO, IL-6 and TNF-α, signposts substantial antiinflammatory potential of the compound. Overall, EFD has shown better binding affinity with target molecules, acceptable ADMET profile, potent antiproliferative and apoptotic nature and significant reduction in inflamed prostate mass of rats. The present study demonstrates acceptable physicochemical and pharmacokinetic properties of the compound with excellent drugable nature, hence EFD in the form of standardized formulation can be developed as primary or adjuvant therapy against PCa and toxins-induced gonadotoxicity.

Isolation and functional characterization of a glucose-6-phosphate/phosphate translocator (IbG6PPT1) from sweet potato (Ipomoea batatas (L.) Lam.).

Sweet potato (Ipomoea batatas (L.) Lam.) is a good source of carbohydrates, an excellent raw material for starch-based industries, and a strong candidate for biofuel production due to its high starch content. However, the molecular basis of starch biosynthesis and accumulation in sweet potato is still insufficiently understood. Glucose-6-phosphate/phosphate translocators (GPTs) mediate the import of glucose-6-phosphate (Glc6P) into plastids for starch synthesis. Here, we report the isolation of a GPT-encoding gene, IbG6PPT1, from sweet potato and the identification of two additional IbG6PPT1 gene copies in the sweet potato genome. IbG6PPT1 encodes a chloroplast membrane-localized GPT belonging to the GPT1 group and highly expressed in storage root of sweet potato. Heterologous expression of IbG6PPT1 resulted in increased starch content in the leaves, root tips, and seeds and soluble sugar in seeds of Arabidopsis thaliana, but a reduction in soluble sugar in the leaves. These findings suggested that IbG6PPT1 might play a critical role in the distribution of carbon sources in source and sink and the accumulation of carbohydrates in storage tissues and would be a good candidate gene for controlling critical starch properties in sweet potato.