Anti-obesity activity of anthocyanin and carotenoid extracts from color-fleshed sweet potatoes

Harnessing the health benefits of purple and yellow-fleshed sweet potatoes: Phytochemical composition, stabilization methods, and industrial utilization- A review

Purple-fleshed sweet potato (PFSP) and yellow-fleshed sweet potato (YFSP) are crops highly valued for their nutritional benefits and rich bioactive compounds. These compounds include carotenoids, flavonoids (including anthocyanins), and phenolic acids etc. which are present in both the leaves and roots of these sweet potatoes. PFSP and YFSP offer numerous health benefits, such as antioxidant, anti-inflammatory, anti-cancer, and neuroprotective properties. The antioxidant activity of these sweet potatoes holds significant potential for various industries, including food, pharmaceutical, and cosmetics. However, a challenge in utilizing PFSP and YFSP is their susceptibility to rapid oxidation and color fading during processing and storage. To address this issue and enhance the nutritional value and shelf life of food products, researchers have explored preservation methods such as co-pigmentation and encapsulation. While YFSP has not been extensively studied, this review provides a comprehensive summary of the nutritional value, phytochemical composition, health benefits, stabilization techniques for phytochemical, and industrial applications of both PFSP and YFSP in the food industry. Additionally, the comparison between PFSP and YFSP highlights their similarities and differences, shedding light on their potential uses and benefits in various food products.

Natural Pigments Recovery from Food By-Products: Health Benefits towards the Food Industry

Given the health risks associated with synthetic colorants, natural pigments have emerged as a promising alternative. These renewable choices not only provide health benefits but also offer valuable technical and sensory properties to food systems. The effective application of natural colorants, however, requires the optimization of processing conditions, exploration of new sources, and development of novel formulations to ensure stability and maintain their inherent qualities. Several natural pigment sources have been explored to achieve the broad color range desired by consumers. The purpose of this review is to explore the current advances in the obtention and utilization of natural pigments derived from by-products, which possess health-enhancing properties and are extracted through environmentally friendly methods. Moreover, this review provides new insights into the extraction processes, applications, and bioactivities of different types of pigments.

Unveiling the multifaceted world of anthocyanins: Biosynthesis pathway, natural sources, extraction methods, copigmentation, encapsulation techniques, and future food applications

Numerous datasets regarding anthocyanins have been noted elsewhere. These previous studies emphasized that all processes must be carried out meticulously from the source used to obtain anthocyanins to their inclusion in relevant applications. However, today, full standardization has not yet been achieved for these processes. For this, presenting the latest developments regarding anthocyanins under one roof would be a useful approach to guide the scientific literature. The current review was designed to serve the stated points. In this context, their biosynthesis pathway was elaborated. Superior potential of fruits and certain by-products in obtaining anthocyanins was revealed compared to their other counterparts. Health-promoting benefits of anthocyanins were detailed. Also, the situation of innovative techniques (ultrasound-assisted extraction, subcritical water extraction, pulse electrical field extraction, and so on) in the anthocyanin extraction was explained. The stability issues, which is one of the most important problems limiting the use of anthocyanins in applications were discussed. The role of copigmentation and various encapsulation techniques in solving these stability problems was summarized. This critical review is a map that provides detailed information about the processes from obtaining anthocyanins, which stand out with their functional properties, to their incorporation into various systems.

Purple sweet potato anthocyanins normalize the blood glucose concentration and restore the gut microbiota in mice with type 2 diabetes mellitus

Background

This study investigated the effects of purple sweet potato anthocyanins (PSPA) in a type 2 diabetes mellitus (T2DM) mouse model.

Methods

Sixty-five male mice were randomly divided into one control group and four experimental groups, which were fed with a high-fat diet and intraperitoneally injected with streptozotocin (STZ) to induce T2DM. The model mice were treated with 0 (M), 227.5 (LP), 455 (MP), or 910 (HP) mg/kg PSPA for ten days. ELISA, 16S rRNA sequencing, and hematoxylin and eosin staining were used to assess blood biochemical parameters, gut microbial composition, and liver tissue structure, respectively.

Results

The FBG concentration was significantly decreased in the LP (6.32 ± 1.05 mmol/L), MP (6.32 ± 1.05 mmol/L), and HP (5.65 ± 0.83 mmol/L) groups; the glycosylated hemoglobin levels were significantly decreased in the HP group (14.43 ± 7.12 pg/mL) compared with that in the M group (8.08 ± 1.04 mmol/L; 27.20 ± 7.72 pg/mL; P < 0.05). The PSPA treated groups also increased blood glutathione levels compared with M. PSPA significantly affected gut microbial diversity. The Firmicutes/Bacteroidetes ratio decreased by 38.9 %, 49.2 %, and 15.9 % in the LP, MP, and HP groups compared with that in the M group (0.62). The PSPAs treated groups showed an increased relative abundance of Lachnospiraceae_Clostridium, Butyricimonas, and Akkermansia and decreased abundance of nine bacterial genera, including Staphylococcus.

Conclusion

PSPA reduced blood glucose levels, increased serum antioxidant enzymes, and optimized the diversity and structure of the gut microbiota in mice with T2DM.

Anti-diabetic effect of anthocyanin cyanidin-3-O-glucoside: data from insulin resistant hepatocyte and diabetic mouse

BACKGROUND

Anthocyanins are a group of natural products widely found in plants. They have been found to alleviate the disorders of glucose metabolism in type 2 diabetes mellitus (T2DM), while the underlying mechanisms remain unclear.

METHODS

HepG2 and L02 cells were incubated with 0.2 mM PA and 30 mM glucose for 24 h to induce IR, and cells treated with 5 mM glucose were used as the control. C57BL/6 J male mice and db/db male mice were fed with a chow diet and gavaged with pure water or cyanidin-3-O-glucoside (C3G) solution (150 mg/kg/day) for 6 weeks.

RESULTS

In this study, the anthocyanin C3G, extracted from red bayberry, was found to alleviate disorders of glucose metabolism, which resulted in increased insulin sensitivity in hepatocytes, and achieved by enhancing the glucose consumption as well as glycogen synthesis in insulin resistance (IR) hepatpcytes. Subsequently, the expression of key proteins involved in IR was detected by western blotting analysis. Protein tyrosine phosphatase-1B (PTP1B), a negative regulator of insulin signaling, could reduce cellular sensitivity to insulin by inhibiting the phosphorylation of insulin receptor substrate-2 (IRS-2). Results of this study showed that C3G inhibited the increase in PTP1B after high glucose and palmitic acid treatment. And this inhibition was accompanied by increased phosphorylation of IRS proteins. Furthermore, the effect of C3G on improving IR in vivo was validated by using a diabetic db/db mouse model.

CONCLUSION

These findings demonstrated that C3G could alleviate IR in vitro and in vivo to increase insulin sensitivity, which may offer a new insight for regulating glucose metabolism during T2DM by using the natural dietary bioactive components. C3G promotes the phosphorylation of IRS-2 proteins by suppressing the expression of PTP1B, and then enhances the sensitivity of hepatocyte to insulin.

The Potential of the Flavonoid Content of Ipomoea batatas L. as an Alternative Analog GLP-1 for Diabetes Type 2 Treatment-Systematic Review

Ipomoea batatas L. (IBL) has gained significant popularity as a complementary therapy or herbal medicine in the treatment of anti-diabetes. This review seeks to explore the mechanism by which flavonoid compounds derived from IBL exert their anti-diabetic effects through the activation of GLP-1. The review article refers to the PRISMA guidelines. In order to carry out the literature search, electronic databases such as Science Direct, Crossref, Scopus, and Pubmed were utilized. The search query was based on specific keywords, including Ipomoea batatas OR sweet potato AND anti-diabetic OR hypoglycemic. After searching the databases, we found 1055 articles, but only 32 met the criteria for further review. IBL contains various compounds, including phenolic acid, flavonols, flavanols, flavones, and anthocyanins, which exhibit activity against anti-diabetes. Flavonols, flavanols, and flavones belong to a group of flavonoids that possess the ability to form complexes with AlCl3 and Ca2+. The intracellular L cells effectively retain Ca2+, leading to the subsequent release of GLP-1. Flavonols, flavones, and flavone groups have been found to strongly interact with DPP-IV, which inhibits the degradation of GLP-1. The anti-diabetic activity of IBL is attributed to the mechanism that effectively increases the duration of GLP-1 in the systemic system, thereby prolonging its half-life.

Unlocking the Potential of the ANN Optimization in Sweet Potato Varieties Drying Processes

This study explores the unexploited potential of Artificial Neural Network (ANN) optimization techniques in enhancing different drying methods and their influence on the characteristics of various sweet potato varieties. Focusing on the intricate interplay between drying methods and the unique characteristics of white, pink, orange, and purple sweet potatoes, the presented experimental study indicates the impact of ANN-driven optimization on food-related characteristics such as color, phenols content, biological activities (antioxidant, antimicrobial, anti-hyperglycemic, and anti-inflammatory), chemical, and mineral contents. The results unveil significant variations in drying method efficacy across different sweet potato types, underscoring the need for tailored optimization strategies. Specifically, purple sweet potatoes emerge as robust carriers of phenolic compounds, showcasing superior antioxidant activities. Furthermore, this study reveals the optimized parameters of dried sweet potato, such as total phenols content of 1677.76 mg/100 g and anti-inflammatory activity of 8.93%, anti-hyperglycemic activity of 24.42%. The upgraded antioxidant capability is presented through DPPH●, ABTS●+, RP, and SoA assays with values of 1500.56, 10,083.37, 3130.81, and 22,753.97 μg TE/100 g, respectively. Additionally, the moisture content in the lyophilized sample reached a minimum of 2.97%, holding favorable chemical and mineral contents. The utilization of ANN optimization proves instrumental in interpreting complex interactions and unlocking efficiencies in sweet potato drying processes, thereby contributing valuable insights to food science and technology.

Effects of Foods of Mesoamerican Origin in Adipose Tissue and Liver-Related Metabolism

Adipose tissue and liver metabolism play a key role in maintaining body homeostasis; therefore, their impairment conduces a pathological state. Nowadays, occidental lifestyle is a common etiological issue among a variety of chronic diseases, while diet is a unique strategy to prevent obesity and liver metabolism impairment and is a powerful player in the treatment of metabolic-related diseases. Mesoamerican foods are rich in bioactive molecules that enhance and improve adipose tissue and liver performance and represent a prophylactic and therapeutic alternative for disorders related to the loss of homeostasis in the metabolism of these two important tissues.

A Comprehensive Review of Phytonutrients as a Dietary Therapy for Obesity

Obesity is a complex medical condition mainly caused by eating habits, genetics, lifestyle, and medicine. The present study deals with traditional diets like the Mediterranean diet, Nordic diet, African Heritage diet, Asian diet, and DASH, as these are considered to be sustainable diets for curing obesity. However, the bioavailability of phytonutrients consumed in the diet may vary, depending on several factors such as digestion and absorption of phytonutrients, interaction with other substances, cooking processes, and individual differences. Hence, several phytochemicals, like polyphenols, alkaloids, saponins, terpenoids, etc., have been investigated to assess their efficiencies and safety in the prevention and treatment of obesity. These phytochemicals have anti-obesity effects, mediated via modulation of many pathways, such as decreased lipogenesis, lipid absorption, accelerated lipolysis, energy intake, expenditure, and preadipocyte differentiation and proliferation. Owing to these anti-obesity effects, new food formulations incorporating these phytonutrients were introduced that can be beneficial in reducing the prevalence of obesity and promoting public health.

Melatonin promotes the restoration of bone defects via enhancement of miR-335-5p combined with inhibition of TNFα/NF-κB signaling

Accelerating the repair of a bone defect is crucial clinically due to the increased prevalence of trauma, tumor, and infections in bone. Studies have found that excess acute and chronic inflammation attenuate osteogenic differentiation of BMSCs (bone marrow mesenchymal stem cells). Moreover, TNF-α and NF-κB could inhibit osteoblasts differentiation of BMSCs and promote osteoclastogenesis via multiple mechanisms, such as increasing osteoclast precursor cells and acting synergistically with cell cytokines. However, melatonin could inhibit the expression of TNFα/NF-κB and promote bone formation by activating the Wnt/β-catenin signaling pathway. However, there has been no evidence regarding the effect of melatonin on TNFα/NF-κB-inhibited osteoblastogenesis and bone formation. This study aimed to investigate the role of melatonin on TNFα/NF-κB-inhibited osteoblastogenesis and bone formation. Micro-CT, high-throughput screening, overexpression, and other methods were used, and we found that the number of osteoblasts was elevated with melatonin treatment. Additionally, TNFα/NF-κB signaling was inhibited, while miR-335-5p expression increased markedly following treatment with melatonin. Furthermore, miR-335-5p negatively regulated TNFα/NF-κB signaling, while miR-335-5p inhibitor ameliorated the effects of melatonin on TNFα/NF-κB. In conclusion, melatonin facilitates osteogenesis in bone defect healing by enhancing miR-335-5p expression and inhibiting the TNFα/NF-κB pathway.

Optimization of Major Extraction Variables to Improve Recovery of Anthocyanins from Elderberry by Response Surface Methodology

Elderberry, which is well known for its richness in anthocyanin, is attracting attention in the bioindustry as a functional material with high antioxidant capacity. The aim of this study is to optimize extraction conditions to more effectively recover anthocyanins from elderberry. In a fundamental experiment to determine the suitable solvent, various GRAS reagents, such as acetone, ethanol, ethyl acetate, hexane, and isopropyl alcohol, were used, and total phenol and anthocyanin contents were detected as 9.0 mg/g-biomass and 5.1 mg/g-biomass, respectively, only in the extraction using ethanol. Therefore, ethanol was selected as the extraction solvent, and an experimental design was performed to derive a response surface model with temperature, time, and EtOH concentration as the main variables. The optimal conditions for maximal anthocyanin recovery were determined to be 20.0 °C, 15.0 min, and 40.9% ethanol, and the total anthocyanin content was 21.0 mg/g-biomass. In addition, the total phenol and flavonoid contents were detected as 67.4 mg/g-biomass and 43.8 mg/g-biomass, respectively. The very simple and economical extraction conditions suggested in this study contributed to improving the utilization potential of anthocyanin, a useful antioxidant derived from elderberry.

Sweet potato extract alleviates high-fat-diet-induced obesity in C57BL/6J mice, but not by inhibiting pancreatic lipases

Scope and aim

Sweet potato is widely consumed as a healthy and nutritive vegetable containing bioactive constituents for health promotion. This study investigated the beneficial impact of white-fleshed sweet potato extract (SPE) on high fat diet (HFD)-induced obese mice.

Methods and results

First, SPE, in which resin glycoside was found as the dominant constituent, was suggested as a potential anti-obesity agent, because 20-70% pancreatic lipase (PL) inhibition was measured with SPE by in vitro turbidity assay and pNPP assay. Hence, next, the effect of SPE on obese mice was detected by oral administration of HFD supplemented with 6% SPE on C57BL/6J mice for 9 weeks. Surprisingly, being the opposite of what was typically observed from a lipase inhibitor such as orlistat, the fecal fat content in SPE-fed obese mice was decreased (p < 0.01). Meanwhile, 6% SPE supplement indeed significantly ameliorated HFD-induced obesity in mice, including body weight gain, fat accumulation, adipocyte enlargement, insulin resistance, and hepatic steatosis (p < 0.05). The improved liver steatosis was found associated with a down-regulating action of SPE on nuclear factor kappa B activation in HFD-fed mice. The anti-obesity influence of SPE was also confirmed on the HepG2 cell model for non-alcoholic fatty liver disease (NAFLD).

Conclusion

These results indicate that SPE, as a dietary supplement, has the great potential for weight control and treating hepatic steatosis, possibly through a different action mechanism from that of orlistat.

Sweet Potato Is Not Simply an Abundant Food Crop: A Comprehensive Review of Its Phytochemical Constituents, Biological Activities, and the Effects of Processing

Nowadays, sweet potato (Ipomoea batata L.; Lam.) is considered a very interesting nutritive food because it is rich in complex carbohydrates, but as a tubercle, contains high amounts of health-promoting secondary metabolites. The aim of this review is to summarize the most recently published information on this root vegetable, focusing on its bioactive phytochemical constituents, potential effects on health, and the impact of processing technologies. Sweet potato is considered an excellent source of dietary carotenoids, and polysaccharides, whose health benefits include antioxidant, anti-inflammatory and hepatoprotective activity, cardiovascular protection, anticancer properties and improvement in neurological and memory capacity, metabolic disorders, and intestinal barrier function. Moreover, the purple sweet potato, due to its high anthocyanin content, represents a unique food option for consumers, as well as a potential source of functional ingredients for healthy food products. In this context, the effects of commercial processing and domestic cooking techniques on sweet potato bioactive compounds require further study to understand how to minimize their loss.

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.

Effect of food processing on antioxidants, their bioavailability and potential relevance to human health

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Processing alters the amount, matrix interaction, and structure of antioxidants.

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It is not easy to dissociate processing effects from food matrix effects.

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It is still difficult to make general statements on the effects of processing on bioavailability.

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Facilitated release by heat, pressure, etc. contributes to increased bioaccessibility.

It has long been recognized that the antioxidants present in fresh plant materials may be very different to those we ingest via our foods. This is often due to the use of food processing strategies involving thermal/non-thermal treatments. Current research mostly focuses on determining what is present in vegetative starting materials; how this is altered during processing; how this influences activity in the gut and following uptake into bloodstream; and which in vivo physiological effects this may have on human body. Having a better understanding of these different steps and their importance in a health-and-nutrition-context will place us in a better position to breed for improved crop varieties and to advise the food industry on how to optimize processing strategies to enhance biochemical composition of processed foods. This review provides an overview of what is currently known about the influence which food processing treatments can have on antioxidants and gives some pointers as to their potential relevance.

Sweet Potato New Varieties Screening Based on Morphology, Pulp Color, Proximal Composition, and Total Dietary Fiber Content via Factor Analysis and Principal Component Analysis

A sample set of 18 sweet potatoes [Ipomoea batatas (L.) Lam] segmented into six registered cultivars and 12 new varieties were evaluated. The 142 tuberous roots were obtained from a sweet potato germplasm bank (BAG-sweet potato; -27.417713768824555 and -49.64874168439556), specifically from plants belonging to a sweet potato breeding program. All samples were characterized according to their morphology, instrumental pulp color, proximate composition, and total dietary fiber. The analytical results were submitted to parametric and non-parametric statistical tests for sample variance data comparison. Moreover, the screening of the cultivars and new varieties was performed by exploratory statistical analysis, factor analysis (FA), and principal component analysis (PCA). From the sixteen independent variables that characterized the samples, the exploratory FA identified thirteen that had a communality greater than 0.7, with 92.08% of assertiveness. The PCA generated 4 principal components able to account for 84.01% of the explanatory variance. So, among the six registered cultivars, SCS372 Marina and SCS370 Luiza showed the capability to be employed as cultivars for production. Among the 12 sweet potato new varieties, samples 17025-13, 17125-10, and 17117 met the requirements for patent and registration. These results will be useful to farmers who wish to use these sweet potatoes in the development of their crops.

Combining Metabolomics and Transcriptomics to Reveal the Mechanism of Coloration in Purple and Cream Mutant of Sweet Potato (Ipomoea batatas L.)

Purple sweet potato is considered as a healthy food because of its high anthocyanins. To understand the coloring mechanism and quality change between purple-fleshed sweet potato (cv. Xuzi201) and its cream fleshed mutant (M1001), a combined metabolomic and transcriptomic analysis was performed. The metabolome data showed that 4 anthocyanins, 19 flavones, 6 flavanones, and 4 flavonols dramatically decreased in M1001, while the contents of 3 isoflavones, 3 flavonols, 4 catechins, and 2 proanthocyanins increased. Transcriptomic analyses indicated that the expression of 49 structural genes in the flavonoid pathway and transcription factors (TFs) (e.g., bHLH2, R2R3-MYB, MYB1) inducting anthocyanin biosynthesis were downregulated, but the repressor MYB44 was upregulated. The IbMYB1-2 gene was detected as a mutation gene in M1001, which is responsible for anthocyanin accumulation in the storage roots. Thus, the deficiency of purple color in the mutant is due to the lack of anthocyanin accumulation which was regulated by IbMYB1. Moreover, the accumulation of starch and aromatic volatiles was significantly different between Xuzi201 and M1001. These results not only revealed the mechanism of color mutation but also uncovered certain health-promoting compounds in sweet potato.

Purple sweet potato leaf extracts suppress adipogenic differentiation of human bone marrow-derived mesenchymal stem cells

Purple sweet potato (Ipomoea batatas L.) leaf extract (PSPLE) is known to exhibit various biological effects. However, the anti-adipogenic effects of PSPLE on mesenchymal stem cells (MSCs) remain unknown. In the present study, we investigated the effect of PSPLE on the adipogenic differentiation of human bone marrow MSCs. PSPLE treatment significantly reduced lipid accumulation and triglyceride levels during adipogenic differentiation. PSPLE suppressed the expression of PPARγ and C/EBPα, which are the master transcription factors orchestrating adipogenesis; moreover, it inhibited the expression of adiponectin, adipocyte protein 2 (aP2), and lipoprotein lipase (LPL), which are downstream target genes involved in adipogenic differentiation. Furthermore, PSPLE treatment suppressed glucose transporter 4 expression and intracellular glucose uptake and significantly inhibited the adipogenic differentiation induced factor-stimulated Akt signaling activation. These results indicate that PSPLE suppresses the differentiation of undifferentiated MSCs into adipocyte lineages and inhibits the terminal differentiation from preadipocytes into mature adipocytes. PRACTICAL APPLICATION: The increase in the prevalence of obesity worldwide is a problem today. Obesity is induced by an excessive accumulation of adipocytes and causes obesity-related diseases, such as diabetes, hypertension, and hyperlipidemia. Natural compounds derived from plants and fruits have a variety of biological activities and are expected to exert therapeutic effects against various diseases. This study shows that purple sweet potato (Ipomoea batatas L.) leaf extract (PSPLE) suppresses adipogenesis of bone marrow-derived mesenchymal stem cells. Thus, PSPLE may be a novel functional food for controlling obesity.

Immobilization of dihydroflavonol 4-reductase on magnetic Fe3O4/PVIM/Ni2+ nanomaterials for the synthesis of anthocyanidins

Anthocyanidins are one subclass of flavonoids in plants and possess important biological functions. A Fe3O4/PVIM/Ni2+-immobilized DFR enzyme was prepared using nano-biotechnology, which can catalyze the synthesis of anthocyanidins in vitro.

Protective Effect of Carotenoid Extract from Orange-Fleshed Sweet Potato on Gastric Ulcer in Mice by Inhibition of NO, IL-6 and PGE2 Production

Ipomoea batatas (L.) Lam., Convolvulaceae is widely distributed in Asian areas from tropical to warm-temperature regions. Their tubers are known for their antioxidant, anti-bacterial, anti-diabetic, wound healing, anti-inflammatory, and anti-ulcer activities. The preventive and therapeutic effects of orange-fleshed sweet potato on gastric ulcers have not been investigated. In this study, the carotenoid extract (CE) of orange-fleshed sweet potato was found to protect against gastric ulcers induced by HCl/ethanol in mice. The anti-inflammatory and antioxidant activities of the carotenoid pigment extract were also evaluated as possible evidence of their protective effects. Administration of CE reduced gastric ulcers. Oral administration of CE (100 mg/kg) protected against gastric ulcers by 78.1%, similar to the positive control, sucralfate (77.5%). CE showed potent reducing power and decreased nitric oxide production in a mouse macrophage cell line, RAW 264.7, in a concentration-dependent manner. The production of the inflammatory cytokine interleukin-6 and prostaglandin E₂ was also reduced by CE in a dose-dependent manner. The high carotenoid content of orange-fleshed sweet potato could play a role in its protective effect against gastric ulcers. This result suggests the possibility of developing functional products using this nutrient-fortified material.

Anti-obesity effect of Auricularia heimuer fruiting body alcohol extraction on obese mice and crucial metabolite pathway analysis by liquid chromatography-tandem mass spectrometry

In recent years, the increasing obese and overweight population has become a worldwide public health problem, as there is no effective medication to control obesity. Auricularia heimuer is rich in active substances that have potential biologically active functions. The anti-obesity effect and mechanism of Auricularia heimuer fruiting body alcohol extraction (AHA, 150-600 mg/kg·bw) was investigated in obese mice by assessing changes in endogenous liver metabolites using a liquid chromatography-tandem mass spectrometry approach. The aim of this study was to identify an effective food to control human obesity. AHA of 600 mg/kg·bw (HC) significantly decreased body weight and improved serum biochemistry indices. Sixty-eight liver metabolites were identified and significantly separated among the normal, high-fat diet (HFD), and HC groups. Moreover, the metabolic analysis revealed that HC significantly regulated specific metabolites in mice including amino acids, lipids, and carbohydrate compounds. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that HC was significantly involved in different metabolite pathways including arachidonic acid metabolism, galactose metabolism, carbohydrate digestion and absorption, linoleic acid metabolism, and starch and sucrose metabolism. Eight weeks after supplementing with HC, major metabolites in related pathways that were disrupted by an HFD were restored to normal levels, suggesting that HC had anti-obesity activity.

Immune-Enhancing Effects of a Novel Glucan from Purple Sweet Potato Ipomoea batatas (L.) Lam on RAW264.7 Macrophage Cells via TLR2- and TLR4-Mediated Pathways

PSPP-1 was obtained from purple sweet potato, and the effects of PSPP-1 on the immune modulation on macrophage cells were investigated for the first time. PSPP-1 promoted RAW264.7 proliferation and increased the total cell percentage in DNA synthesis and mitosis phases, and the cell morphology changed in volume and appearance. Additionally, the RAW264.7 immune functions of phagocytic activity and nitric oxide, reactive oxygen species, and cytokine production were improved by PSPP-1. The western blot experiment showed that PSPP-1 could activate toll-like receptor 2 and toll-like receptor 4-mediated pathways, and the expressions of proteins in MyD88-dependent, mitogen-activated protein kinase (MAPK)-signaling, NF-κB-signaling, AP-1 signaling, and TRIF-dependent pathways were improved markedly. Molecular docking and Biolayer Interferometry study further indicated that PSPP-1 could recognize and bind TLR2 and TLR4 by targeting the binding sites with a strong affinity. It suggested that PSPP-1 could enhance immunity via TLR2- and TLR4-mediated pathways, and it could be explored as an immunomodulatory agent.