Effects of microwave radiation on the physicochemical properties, structure, and digestibility of the synthesized different crystal forms of malic acid starch ester.

The effects of microwave combined with L-malic acid treatment on the degree of substitution (DS), structure, physicochemical properties, and digestibility of sweet potato starch (A-type), potato starch (B-type), and pea starch (C-type) were evaluated. The order of DS obtained was: DSM-POS > DSM-SPS > DSM-PES. Fourier transform-infrared spectroscopy (FT-IR) showed that the obtained modified starch produced a new absorption band at 1735 cm-1. Scanning electron microscopy (SEM) and polarized light microscopy indicated that different types of native starches exhibited different granular morphologies and appeared to have different degrees of damage, but still had polarized crosses after modification. Sweet potato starch had the smallest particle size, while potato starch had the largest. X-ray diffractometry (XRD) showed that the modified starches still retained the same crystal structure as the native starches, but the relative crystallinity decreased. The apparent viscosity and swelling power of modified starches dropped, but their water/oil holding capacity, amylose content, and resistant starch content all increased. The results demonstrate that the degree of influence on the structure, physicochemical properties, and digestibility of different starches varies under the same modification conditions.

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.

Structural characterization and induction of tumor cell apoptosis of polysaccharide from purple sweet potato (Ipomoea batatas (L.) Lam).

The carbohydrate is the main ingredient of purple sweet potato. A polysaccharide, named PSP, was separated and purified from purple sweet potato by extraction with hot water, precipitation with ethanol, deproteinization with Sevag reagent and column chromatography with Sephadex G-100. The purity and structure were studied with HPLC, UV-Vis, GC-MS and NMR. The PSP is a neutral polysaccharide with Mw of 470 kDa. The monosaccharide composition of PSP contained D-xylose, d-glucose, D-galactose with ratio of 1.0: 8.3: 1.3. The backbone of PSP was composed of the residues of →6)-D-Glcp-(1 â†’ and →2, 6)-D-Glcp-(1→. The branches of PSP contained the residues of →3)-D-Galp-(1→, and D-Xylp-(1→. The antitumor activity in vitro of PSP was analyzed with HT-29 cells. And the SEM, AO staining, MDC staining and hoechst 33342 staining were performed to study the effect on apoptosis of HT-29 cells by PSP. The results revealed that the PSP can significantly inhibit the proliferation of HT-29 cells from induction apoptosis. The manuscript provided valuable knowledges on structural characteristics of the polysaccharides from purple 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.

The Protective Effect of Sweet Potato Root Tuber on Chemotherapy-Induced Thrombocytopenia.

SCOPE: Sweet potato (Ipomoea batatas L.) is one of the leading crops worldwide, containing high nutritional components such as fiber and polyphenols. Root tuber of Simon 1 (SIMON), a cultivar of sweet potato, is a folk food in China with a hemostasis function but lacking experimental data support. METHODS AND RESULTS: Now the protective effect of SIMON on chemotherapy-induced thrombocytopenia (CIT), a serious complication of cancer treatment, is investigated for the first time by a CIT mouse model induced by intraperitoneal injection of carboplatin. As a result, SIMON raises the number of peripheral platelets, white blood cells, and bone marrow nucleated cells in CIT mice significantly. Besides, carboplatin-induced atrophy of the thymus, spleen, and disordered metabolism of the inflammatory immune system and glycerophospholipids are also reversed by SIMON. Phytochemical analysis of SIMON indicates 16 compounds including eight phenolic derivatives, which might be associated with its anti-CIT bioactivity. CONCLUSION: Sweet potato (SIMON) may be an efficient function food in the prevention of bleeding disorders.

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.

Comparative study of thermo-mechanical, rheological, and structural properties of gluten-free model doughs from high hydrostatic pressure treated maize, potato, and sweet potato starches.

Effects of high hydrostatic pressure (HHP, 100, 300 and 500 MPa for 30 min at 25 °C) treated maize (MS), potato (PS), and sweet potato (SS) starches on thermo-mechanical, rheological, microstructural properties and water distribution of gluten-free model doughs were investigated. Significant differences were found among starch model doughs in terms of water absorption, dough development time, and dough stability at 500 MPa. Total gas production of MS, PS and SS doughs was significantly increased from 541 to 605 mL (300 MPa), 527 to 568 mL (500 MPa) and 551 to 620 mL (500 MPa) respectively as HHP increased. HHP increased storage (G') and loss (G″) modulus in terms of rheological properties suggesting, the higher viscoelastic behavior of starch model doughs. The dough after 500 MPa treatment showed lower degree of dependence of G' on frequency sweep suggesting, the formation of a stable network structure. In addition, continuous abundant water distribution and uniform microstructure were found in MS (300 MPa), PS (500 MPa) and SS (500 MPa) doughs for 60 min fermentation. Thus, the starches after HHP show great application potential in gluten-free doughs with improved characteristics.

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.

Anthocyanin Extract from Purple Sweet Potato Exacerbate Mitophagy to Ameliorate Pyroptosis in Klebsiella pneumoniae Infection.

Given the rise of morbidity and mortality caused by Klebsiella pneumoniae (KP), the increasing number of strains resistant to antibiotics, and the emergence of hypervirulent Klebsiella pneumonia, treatment of KP infection becomes difficult; thus, novel drugs are necessary for treatment. Anthocyanins, or natural flavonoids, have an extensive effect against bacterial infection. However, few studies on anti-KP are identified. Here, we evaluated the therapeutic effect of purple sweet potato anthocyanins (PSPAs) on KP, containing 98.7% delphinidin 3-sambubioside. Results showed that KP-infected mice after PSPAs treatment manifested decreased mortality, weakened lung injury, dampened inflammatory responses, and reduced bacterial systemic dissemination in vivo. In Vitro, PSPAs significantly suppressed pyroptosis and restricted NLRP3 inflammasome activation in alveolar macrophages infected with KP. As for the mechanism, PSPAs promote mitophagy by recruiting Parkin to the mitochondria. PSPAs-conferred mitophagy increased mitochondrial membrane potential and decreased mitochondrial reactive oxygen species and mitochondrial DNA, resulting in impaired NLRP3 inflammasome activation. In addition, the promotion of mitophagy by PSPAs required the Nrf2 signaling pathway. Collectively, these findings suggest that PSPAs are a potential option for the treatment of KP infection.

Sweet potato (Ipomoea batatas L.) leaf polyphenols ameliorate hyperglycemia in type 2 diabetes mellitus mice.

The hypoglycemic effects and potential mechanism of sweet potato leaf polyphenols (SPLP) on type 2 diabetes mellitus (T2DM) were investigated. Results showed that oral administration of SPLP to mice could alleviate body weight loss, decrease fasting blood glucose levels (by 64.78%) and improve oral glucose tolerance compared with those of untreated diabetic mice. Furthermore, increased fasting serum insulin levels (by 100.11%), ameliorated insulin resistance and improved hepatic glycogen (by 126.78%) and muscle glycogen (increased by 135.85%) were observed in the SPLP treatment group. SPLP also could reverse dyslipidemia, as indicated by decreased total cholesterol, triglycerides, low density lipoprotein-cholesterol and promoted high density lipoprotein-cholesterol. Histopathological analysis revealed that SPLP could relieve liver inflammation and maintain the islet structure to inhibit ß-cell apoptosis. A quantitative real-time polymerase chain reaction confirmed that SPLP could up-regulate the phosphatidylinositol 3-kinase/protein kinase B/glycogen synthase kinase-3ß signaling pathway to improve glucose metabolism and up-regulate the phosphatidylinositol 3-kinase/protein kinase B/glucose transporter 4 signaling pathway in the skeletal muscle to enhance glucose transport. This study provides useful information to support the application of SPLP as a natural product for the treatment of T2DM.

Preparation and properties of phosphate starches from tuberous roots.

The diversification of raw materials in the starch industries is a current strategy. However, the production of native starches does not meet market demand, and it is essential to expand the knowledge about chemical modifications in the same production line for different sources of starch. Phosphate starches are one of the most abundantly produced and widely used chemically modified starches. However, the effects of this modification may vary with the starch source and the reaction conditions. In this study, arrowroot, cassava and sweet potato starches were modified with sodium trimetaphosphate (STMP)/sodium tripolyphosphate (STPP) mixture under same conditions. The reaction time ranged from 7.5 to 120 min. Unmodified and modified starches were analyzed for phosphorus, amylose, morphology, X-ray diffraction pattern, crystallinity, swelling power, solubility, pasting and thermal properties. Phosphorus content linked to the starches increased with the reaction time, which affected the physicochemical properties of the three starches. The changes were more significant in all reaction times for cassava starch, followed by arrowroot. Due to its intrinsic characteristics, longer reaction times were necessary for more significant changes in sweet potato starch. Regardless of the starch source, as the reaction time increased, the average starch granule diameter, swelling power, solubility and peak viscosity increased. There was a decrease in setback in the longer reaction times for cassava and arrowroot starches. The changes in the reaction times allowed obtaining phosphate tuberous starches with different properties which can meet the demands of the food and non-food industries.

Structural, antioxidant, aroma, and sensory characteristics of Maillard reaction products from sweet potato protein hydrolysates as influenced by different ultrasound-assisted enzymatic treatments.

Effects of energy-divergent ultrasound (EDU), energy-gathered ultrasound (EGU), and energy-gathered ultrasound-microwave (EGUM) on structure, antioxidant activities, aroma, and sensory attributes of Maillard reaction products (MRPs) from sweet potato protein hydrolysates (SPPH) were investigated. EGU and EGUM markedly enhanced the Maillard reaction (MR) progress. FTIR results revealed significant peptide structure changes in MRPs as compared to their SPPHs counterparts. EGU-MRPs exhibited the highest percentages in lower MW fractions of 200-3,000 Da, and presented a significantly enhanced ORAC value of 92.10 µg TE/mL (p < 0.05). Besides, EGU-MRPs and EGUM-MRPs showed higher content and quality of aroma compounds than other MRPs, and presented increased umami, sweetness, and sourness attributes, but decreased bitterness (p < 0.05). Their stronger umami taste was highly correlated to 1-naphthalenol, dodecanoic acid, <200, 200-500, 500-1,000 and 1,000-3,000 Da. Thus, EGU and EGUM assisted enzymatic hydrolysis coupled with MR might be promising ways to produce natural flavoring with improved antioxidant activities.

Acylated Anthocyanins from Red Cabbage and Purple Sweet Potato Can Bind Metal Ions and Produce Stable Blue Colors.

Red cabbage (RC) and purple sweet potato (PSP) are naturally rich in acylated cyanidin glycosides that can bind metal ions and develop intramolecular π-stacking interactions between the cyanidin chromophore and the phenolic acyl residues. In this work, a large set of RC and PSP anthocyanins was investigated for its coloring properties in the presence of iron and aluminum ions. Although relatively modest, the structural differences between RC and PSP anthocyanins, i.e., the acylation site at the external glucose of the sophorosyl moiety (C2-OH for RC vs. C6-OH for PSP) and the presence of coordinating acyl groups (caffeoyl) in PSP anthocyanins only, made a large difference in the color expressed by their metal complexes. For instance, the Al3+-induced bathochromic shifts for RC anthocyanins reached ca. 50 nm at pH 6 and pH 7, vs. at best ca. 20 nm for PSP anthocyanins. With Fe2+ (quickly oxidized to Fe3+ in the complexes), the bathochromic shifts for RC anthocyanins were higher, i.e., up to ca. 90 nm at pH 7 and 110 nm at pH 5.7. A kinetic analysis at different metal/ligand molar ratios combined with an investigation by high-resolution mass spectrometry suggested the formation of metal-anthocyanin complexes of 1:1, 1:2, and 1:3 stoichiometries. Contrary to predictions based on steric hindrance, acylation by noncoordinating acyl residues favored metal binding and resulted in complexes having much higher molar absorption coefficients. Moreover, the competition between metal binding and water addition to the free ligands (leading to colorless forms) was less severe, although very dependent on the acylation site(s). Overall, anthocyanins from purple sweet potato, and even more from red cabbage, have a strong potential for development as food colorants expressing red to blue hues depending on pH and metal ion.

Bioactive Compounds, Antioxidants, and Health Benefits of Sweet Potato Leaves.

Sweet potato (Ipomoea batatas) is one of the most important food crops worldwide and its leaves provide a dietary source of nutrients and various bioactive compounds. These constituents of sweet potato leaves (SPL) vary among varieties and play important roles in treating and preventing various diseases. Recently, more attentions in health-promoting benefits have led to several in vitro and in vivo investigations, as well as the identification and quantification of bioactive compounds in SPL. Among them, many new compounds have been reported as the first identified compounds from SPL with their dominant bioactivities. This review summarizes the current knowledge of the bioactive compositions of SPL and their health benefits. Since SPL serve as a potential source of micronutrients and functional compounds, they can be further developed as a sustainable crop for food and medicinal industries.

Identification of Ipomoea batatas anti-cancer peptide (IbACP)-responsive genes in sweet potato leaves.

IbACP, Ipomoea batatas anti-cancer peptide, a sixteen-amino-acid peptide isolated from sweet potato leaves, is capable of mediating a rapid alkalinization of growth media in plant suspension cells. However, the biological roles of IbACP as a defense peptide have not been studied. The objective of this study was to investigate the effect of IbACP on the accumulation of reactive oxygen species (ROS) and the expression of the defense-related genes. IbACP treatment of sweet potato leaves resulted in marked accumulation of both superoxide ion (O2-) and hydrogen peroxide (H2O2). The activity of peroxidase (POD) was significantly enhanced by IbACP treatment, suggesting that high levels of POD antioxidant activity may be used to scavenge the excess H2O2 in sweet potato plants. The IbACP-related genes were identified by suppression subtractive hybridization (SSH), and were then classified and assigned to the following categories: defense, development, metabolism, signaling, gene expression, and abiotic stress. H2O2 acts as a second messenger for gene activation in some of the IbACP-triggered gene expressions. These results demonstrated that IbACP is part of an integrated strategy for genetic regulation in sweet potato. Our work highlights the function of IbACP and its potential use for enhancing stress tolerance in sweet potato, in an effort to improve our understanding of defense-response mechanisms.

Hair growth-promoting activity of components derived from sweet potato shochu.

Sweet potato shochu oil is one of the by-products of sweet potato shochu production. We investigated the functionality and industrial use of shochu oil as a food-derived raw material. Because of the increased incidence of self-consciousness in people owing to thinning hair, in this study, we examined the hair growth-inducing effects of shochu oil. Minoxidil, the only topical medication approved for hair growth treatment in Japan, was used as a control for the evaluation of hair growth-promoting activity of shochu oil. Human follicle dermal papilla cells treated with shochu oil showed upregulated expression of vascular endothelial growth factor in a concentration-dependent manner, indicating that shochu oil induced the activation of the hair growth cycle. In vivo, epidermal treatment with shochu oil also promoted hair growth in C3H mice. More than 35 components were detected in shochu oil via gas chromatography-mass spectrometry. The main components, accounting for 98.5% of shochu oil, were as follows, in order of decreasing concentration: ethyl palmitate, ethyl linoleate, ethyl oleate, ethyl stearate, ethyl caprate, ethyl laurate, ethyl myristate, and ethyl α-linolenate. Among these, ethyl palmitate, ethyl linoleate, and ethyl α-linolenate promoted hair growth in C3H mice. These results indicate that shochu oil can be used as a hair restorer. To the best of our knowledge, this study is the first to demonstrate the hair growth-promoting activity of shochu oil.

Effect of spray drying on the polyphenolic compounds present in purple sweet potato roots: Identification of new cinnamoylquinic acids.

The effect of spray drying on the different polyphenolic compounds present in the root of a purple-fleshed sweet potato variety of Ipomoea batatas native from Peru was performed by HPLC-QTOF-MSMS. Nine anthocyanins, including four peonidin, three cyanidin and two pelargonidin derivatives glycosylated with sophorose and/or glucose and acylated with caffeic, ferulic and p-hydroxybenzoic acid were identified. Twenty nine cinnamoylquinic acids (CiQA), including eight mono-CiQA, fourteen di-CiQA, and five tri-CiQA, were identified on the base of their MS fragmentation profile. Relevant amounts of feruloylquinic acid derivatives were identified. Among them, some di and tri-CiQAs containing feruloyl and caffeoyl moieties in their structures, and di-feruloylquinic acids were reported here, for the first time, in Ipomoea. Spray drying process negatively affected the different phenolic groups, with polyphenol losses representing around 90% of the initial amounts. Mono-CiQAs presenting feruloyl moieties and mono acylated peonidin derivatives with p-hydroxybenzoic acid were the less affected compounds.

Iron Absorption from Iron-Biofortified Sweetpotato Is Higher Than Regular Sweetpotato in Malawian Women while Iron Absorption from Regular and Iron-Biofortified Potatoes Is High in Peruvian Women.

BACKGROUND: Sweetpotato and potato are fast-maturing staple crops and widely consumed in low- and middle-income countries. Conventional breeding to biofortify these crops with iron could improve iron intakes. To our knowledge, iron absorption from sweetpotato and potato has not been assessed. OBJECTIVE: The aim was to assess iron absorption from regular and iron-biofortified orange-fleshed sweetpotato in Malawi and yellow-fleshed potato and iron-biofortified purple-fleshed potato in Peru. METHODS: We conducted 2 randomized, multiple-meal studies in generally healthy, iron-depleted women of reproductive age. Malawian women (n = 24) received 400 g regular or biofortified sweetpotato test meals and Peruvian women (n = 35) received 500 g regular or biofortified potato test meals. Women consumed the meals at breakfast for 2 wk and were then crossed over to the other variety. We labeled the test meals with 57Fe or 58Fe and measured cumulative erythrocyte incorporation of the labels 14 d after completion of each test-meal sequence to calculate iron absorption. Iron absorption was compared by paired-sample t tests. RESULTS: The regular and biofortified orange-fleshed sweetpotato test meals contained 0.55 and 0.97 mg Fe/100 g. Geometric mean (95% CI) fractional iron absorption (FIA) was 5.82% (3.79%, 8.95%) and 6.02% (4.51%, 8.05%), respectively (P = 0.81), resulting in 1.9-fold higher total iron absorption (TIA) from biofortified sweetpotato (P < 0.001). The regular and biofortified potato test meals contained 0.33 and 0.69 mg Fe/100 g. FIA was 28.4% (23.5%, 34.2%) from the regular yellow-fleshed and 13.3% (10.6%, 16.6%) from the biofortified purple-fleshed potato meals, respectively (P < 0.001), resulting in no significant difference in TIA (P = 0.88). CONCLUSIONS: FIA from regular yellow-fleshed potato was remarkably high, at 28%. Iron absorbed from both potato test meals covered 33% of the daily absorbed iron requirement for women of reproductive age, while the biofortified orange-fleshed sweetpotato test meal covered 18% of this requirement. High polyphenol concentrations were likely the major inhibitors of iron absorption. These trials were registered at www.clinicaltrials.gov as NCT03840031 (Malawi) and NCT04216030 (Peru).