Discovery of a Novel Bioactive Compound in Orange Peel Polar Fraction on the Inhibition of Trimethylamine and Trimethylamine N-Oxide through Metabolomics Approaches and In Vitro and In Vivo Assays: Feruloylputrescine Inhibits Trimethylamine via Suppressing cntA/B Enzyme.

This study compares the inhibitory effects of orange peel polar fraction (OPP) and orange peel nonpolar fraction (OPNP) on trimethylamine (TMA) and trimethylamine N-oxide (TMAO) production in response to l-carnitine treatment in vivo and in vitro. Metabolomics is used to identify bioactive compounds. The research demonstrates that the OPP effectively regulates atherosclerosis-related markers, TMA and TMAO in plasma and urine, compared to the OPNP. Our investigation reveals that these inhibitory effects are independent of changes in gut microbiota composition. The effects are attributed to the modulation of cntA/B enzyme activity and FMO3 mRNA expression in vitro. Moreover, OPP exhibits stronger inhibitory effects on TMA production than OPNP, potentially due to its higher content of feruloylputrescine, which displays the highest inhibitory activity on the cntA/B enzyme and TMA production. These findings suggest that the OPP containing feruloylputrescine has the potential to alleviate cardiovascular diseases by modulating cntA/B and FMO3 enzymes without directly influencing gut microbiota composition.

Milk Fat Globule Membrane Relieves Fatigue via Regulation of Oxidative Stress and Gut Microbiota in BALB/c Mice.

Milk fat globule membranes (MFGMs) are complex structures that incorporate bioactive proteins and lipids to assist in infant development. However, the antifatigue and antioxidant potentials of MFGM have not been investigated. In this study, repeated force swimming measured fatigue in male BALB/c mice fed MFGM and saline for 18 weeks. The MFGM supplementation increased the time to exhaustion by 42.7% at 6 weeks and 30.6% at 14 weeks (p < 0.05). Fatigue and injury-related biomarkers, including blood glucose, lactic acid, and lactate dehydrogenase, were ameliorated after free swimming (p < 0.05). The activity of antioxidant enzymes in blood serum increased at 18 weeks, while malondialdehyde (MDA) content decreased by 45.0% after the MFGM supplementation (p < 0.05). The Pearson correlation analysis showed a high correlation between fatigue-related indices and antioxidant levels. The increased protein expression of hepatic Nrf2 reduced the protein expression of Caspase-3 in the gastrocnemius muscle (p < 0.05). Moreover, the MFGM supplementation increased the relative abundance of Bacteroides, Butyricimonas, and Anaerostipes. Our results demonstrate that MFGM may maintain redox homeostasis to relieve fatigue, suggesting the potential application of MFGM as an antifatigue and antioxidant dietary supplement.

Whey Protein Hydrolysate Renovates Age-Related and Scopolamine-Induced Cognitive Impairment.

Whey protein and its hydrolysates are ubiquitously applied in the food system. However, their effect on cognitive impairment remains unclear. This study aimed to investigate the potential ability of whey protein hydrolysate (WPH) to ameliorate cognitive degeneration. WPH intervention in Crl:CD1 (ICR, Institute for cancer research) mice and aged C57BL/6J mice in a scopolamine-induced cognitive impairment model for 10 days were evaluated. Behavioral tests indicated that WPH intervention improved the cognitive abilities in ICR and aged C57BL/6J mice (p < 0.05). Scopolamine enhanced the Aß1-42 level in the brain tissue, and the WPH intervention exhibited a similar therapeutic effect to donepezil in ICR mice. A noticeable reduction occurred in serum Aß1-42 level of aged mice treated with WPH. The histopathological study of the hippocampus showed that WPH intervention alleviates neuronal damage. Hippocampus proteomic analysis suggested possible mechanisms of WPH action. The relative abundance of Christensenellaceae, a gut microbe related to Alzheimer's disease, was altered by WPH intervention. This study demonstrated that short-term WPH intake protected against memory impairment induced by scopolamine and aging.

Effects of kefir lactic acid bacteria-derived postbiotic components on high fat diet-induced gut microbiota and obesity.

Cellular components, surface layer protein (SLP) and exopolysaccharides (EPS) of postbiotic lactic bacteria (PLAB) can rehabilitate high-fat diet-induced dysbiosis and obese characteristic gut microbiome. However, it is not clear whether and how PLAB components affect gut microbiota and specifically adipocyte gene expression. Furthermore, SLP and EPS of PLAB in combination with polyphenolics of prebiotic wine grape seed flour (GSF) may have greater benefit on high-fat diet (HFD)-induced obesity and gut microbiota imbalance. To investigate interactions, C57BL/6 mice were fed a HFD and orally administered saline (CON), 250 mg/Kg EPS, or 120 mg/Kg SLP or saline with fed 2% GSF (GSF) or combination (42 mg/Kg EPS + 20 mg/Kg SLP + 0.5% GSF; ALL). There were significant reductions of HFD-induced body weight gain, adipose weight, serum triglyceride, and insulin resistance by the SLP and ALL diets compared to CON, with the most profound effect by ALL. ALL significantly affected the distribution of intestinal bacterial genus and species particularly those involved in production of short chain fatty acid (SCFA) and anti-obesogenic action. Microarray analysis from adipose tissue showed that ALL significantly affected expression of genes related to fatty acid biosynthesis, autophagy, inflammatory response, immune response, brown adipose tissue development and response to lipoteichoic acid and peptidoglycan (p < 0.05). Interestingly, expression of Akp13 (A-kinase anchoring protein 13) gene, which is related to body mass index and immune response, was negatively associated with the abundance of obesogenic and SCFAs producing gut bacteria. These data suggest that a combination of postbiotic kefir LAB cellular components and prebiotic GSF establishes a healthy intestinal microbiota that in part was associated with the prevention of obesity and obesity-related diseases.

Health benefits of first and second extraction drum-dried pitted olive pomace.

Olive pomace (OP) is the main by-product of olive oil extraction. After pit and skin removal, OP pulp has high concentrations of dietary fiber and phenolics with high antioxidant capacity. This study evaluated mice health benefits of drum-dried pitted OP pulp obtained after first and second oil extraction. Fresh OP was steam blanched, then pits and skins separated in a pulper/finisher, and pulp drum-dried and milled. OP was characterized by proximate analysis, total soluble phenolics (TSP), individual phenolics, and dietary fiber. Drum-dried pitted OP from first and second extraction was formulated at 10% and 20% in a high fat mice diet. Low fat (5%) and high fat (18%) control diets were also used for comparison. First extraction OP had higher TSP than OP from second extraction. Hydroxytyrosol was the main phenolic in OP. Mice weight gain was lower for the four OP diets compared to high and low-fat control diets. Fecal protein was high for all OP diets, indicating poor protein retention in mice, possibly by phenolics binding of protein and enzymes. Liver weight and adipose tissue were lower in mice consuming the four high fat OP diets compared to high fat control diet. Also, there was no effect on blood glucose by OP in diets. Mice gut microbiota analysis indicated that Actinobacteria decreased in the OP diets compared to the two control diets while Bacteroidetes increased, indicating a positive correlation with reduced body fat and weight. Drum-dried pitted OP is a novel agricultural by-product with its bioactive compounds having the potential to be incorporated in feeds and foods providing health benefits. PRACTICAL APPLICATION: Drum-dried pitted olive pomace can be produced from first or second olive oil extraction byproducts to be used as a shelf-stable healthy food or feed supplement.

Quercetin Ameliorates Insulin Resistance and Restores Gut Microbiome in Mice on High-Fat Diets.

Quercetin is a flavonoid that has been shown to have health-promoting capacities due to its potent antioxidant activity. However, the effect of chronic intake of quercetin on the gut microbiome and diabetes-related biomarkers remains unclear. Male C57BL/6J mice were fed HF or HF supplemented with 0.05% quercetin (HFQ) for 6 weeks. Diabetes-related biomarkers in blood were determined in mice fed high-fat (HF) diets supplemented with quercetin. Mice fed the HFQ diet gained less body, liver, and adipose weight, while liver lipid and blood glucose levels were also lowered. Diabetes-related plasma biomarkers insulin, leptin, resistin, and glucagon were significantly reduced by quercetin supplementation. In feces, quercetin supplementation significantly increased the relative abundance of Akkermansia and decreased the Firmicutes/Bacteroidetes ratio. The expression of genes Srebf1, Ppara, Cyp51, Scd1, and Fasn was downregulated by quercetin supplementation. These results indicated that diabetes biomarkers are associated with early metabolic changes accompanying obesity, and quercetin may ameliorate insulin resistance.

Evaluation of Cellular Absorption and Metabolism of ß-Carotene Loaded in Nanocarriers after In Vitro Digestion.

Three protein emulsifiers encapsulating ß-carotene (BC) with accompanying lipids into nanoemulsions (NEs) or without lipids into nanoparticles (NPs) were fabricated to study the effect of the type of interfacial protein on carrier design and the structure remodeling during digestion on the overall uptake and metabolism of BC in Caco-2 cells. BC-loaded micelles and micellar-like aggregates were collected after in vitro digestion and applied to Caco-2 cell monolayers. The digestion process significantly enhanced the cellular uptake of BC by 1.2-2.2 times and 4.1-8.2 times loaded in NEs and NPs, respectively. Whey protein isolate-based carriers improved the absorption but decreased the metabolism of BC to retinyl palmitate. The presence of lipids was found to improve metabolism and aid the transport of retinoids to the basolateral side of Caco-2 monolayers. Understanding the transportation behavior of the protein-based nanocarries after digestion may contribute to the design of biosafe carriers with higher bioavailability to deliver lipophilic nutrients.

Cooked Black Turtle Beans Ameliorate Insulin Resistance and Restore Gut Microbiota in C57BL/6J Mice on High-Fat Diets.

Colored common beans are associated with health promoting and chronic disease prevention effects. Male C57BL/6J mice were fed high-fat (HF) diets supplemented with cooked black turtle beans (HFB) to prevent obesity related insulin resistance. Mice on both HF and HFB were obese compared to mice fed a low-fat (LF) diet. Plasma low density lipoprotein (LDL) and triglyceride concentrations of mice fed HFB diet were 28% and 36.6% lower than those on HF diet. Homeostatic model assessment of insulin resistance (HOMA-IR) index of mice fed HFB diet was 87% lower than that of mice fed HF diet. Diabetes related biomarkers, gastric inhibitory polypeptide (GIP), leptin, glucagon, and inflammatory cytokines interleukin 4 (IL-4) and IL-5, 10 and 12, IFN-g and TNF-α were significantly affected by HFB diet. Pparα, Cyp7a1 and Fasn were down-regulated by HFB diet while LDL-R, Srebp-2, Adipoq and Slc2a4 were up-regulated by HFB diet. The ratio of Firmicutes/Bacteroidetes (F/B) was also decreased 64.1% by HFB diet compared to HF diet. The results indicated that cooked black turtle bean consumption could ameliorate insulin resistance and lower plasma LDL in mice fed HF diet through glucose signaling pathway and JNK/c-Jun pathway. Meanwhile, cooked black turtle bean consumption restored the gut microbiome.

Effects of Differences in Resistant Starch Content of Rice on Intestinal Microbial Composition.

The aim of this study was to evaluate the effects of resistant starch (RS) and fat levels on the gut microbiome in C57BL/6 mice. Three levels of RS from three varieties of rice were the major source of carbohydrates and fat levels were low (10%) and high (39%). We confirmed that RS decreased the Firmicutes to Bacteroidetes ratio, increased SCFA production by higher Bacteroidaceae and S24-7 abundance, and enriched predicted gene families of glycosidases and functional pathways associated with carbohydrate and glycan metabolism. We also found correlations between microbial taxa and tissue gene expression related to carbohydrate and lipid metabolism. Moreover, increasing RS levels resulted in a molecular ecological network with enhanced modularity and interspecific synergy, which is less sensitive to high fat intervention. Overall, RS as low as 0.44% from cooked rice can modulate gut microbiome in mice, which correlated to a protective effect against deleterious effects of an obesogenic diet.

Modulating storage stability of binary gel by adjusting the ratios of starch and kappa-carrageenan.

This study aimed to investigate the interaction mechanism of the waxy starch and kappa carrageenan (KC) gel with different ratios during co-gelatinization and storage. Water distributions, mobilities and rheological properties of the mixture gels were studied. When KC concentration was low (0.5%KC and 4% starch), the starch dominated the system, and the gel strength was the lowest. When KC concentration increased to 0.75%, the gel had the lowest change rate of fracture force, and the most homogeneous network of the freeze-dried gel was observed. When KC concentration increased to 1.0%, the gel strength was high, but the uneven structure led to the instability of the gel. Overall, the gel with 0.75%KC and 4% starch was the most stable during storage, and the exclusion of the two components to each other was the weakest, resulting in the uniform structure of the gel.

Infusion of trans-resveratrol in micron-scale grape skin powder for enhanced stability and bioaccessibility.

A novel delivery system using micron-scale grape skin powder (GSP) was developed that enhanced loading, stability and bioaccessibility of trans-resveratrol (trans-Res). Vacuum assisted infusion of GSP results in a high yield (~1 mg/g) of trans-Res and improved photostability of infused trans-Res in GSP exposed to UV-A light. The release of trans-Res from GSP was ~ 45% during gastric digestion and the total release in the intestinal phase during sequential digestion processes using low and high bile salts was ~ 70% and ~ 90%, respectively. Moreover, the release of endogenous polyphenols in GSP during simulated gastrointestinal digestion was similar to the release profile of infused resveratrol, suggesting strong interactions of infused resveratrol with the GSP matrix. In summary, this research illustrates a novel approach to utilize food by-products to enhance stability and bioaccessibility of bioactive compounds.

Remodeling of ß-Carotene-Encapsulated Protein-Stabilized Nanoparticles during Gastrointestinal Digestion In Vitro and in Mice.

The remodeling of ß-carotene-encapsulated protein nanoparticles (NPs) during digestion in vitro and in vivo was investigated. The NPs were formed using three different proteins. Hydrolysis of the surface protein during digestion resulted in structure remodeling of NPs and the formation of small-sized micellar-like aggregates below 100 nm, accelerating the release of ß-carotene into the aqueous phase. However, the reduced surface ζ-potential in the intestinal fluid suggested the adsorption of bile salts, favoring the formation of small-sized micellar-like aggregates. A shifted peak of ß-carotene in the micellar phase from 965 cm-1 to about 855 cm-1 in Fourier transform infrared spectroscopy analysis indicated that ß-carotene existed in the amorphous state. Microstructure observation in vivo further confirmed that ß-carotene was loaded in micellar-like aggregates and dispersed uniformly in water. The cellular uptake study showed that the absorption rate of digested NPs was significantly increased by 1.34- to 4.16-fold when compared with undigested NPs.

Interactions in starch co-gelatinized with phenolic compound systems: Effect of complexity of phenolic compounds and amylose content of starch.

Maize starches of different amylose contents were co-gelatinized with caffeic acid (CA), quercetin (Qu) and epigallocatechin gallate (EGCG), respectively. The decomposition temperature of waxy maize starch (WS)-CA blends was increased compared to WS, while that of normal maize starch (MS) and high amylose starch (HS) was decreased. The more complex of the phenolic compounds, the lower the decomposition temperature of the MS. The results of Fourier-transform infrared spectroscopy suggested that CA increased short range ordered structure of gelatinized WS but decreased that of gelatinized MS and HS. Hydrogen bonds associated with CA and starch led to the arrangement of ordered structures in different starch. Nuclear magnetic resonance (NMR) indicated that all hydroxyl groups of CA and EGCG formed hydrogen bonds, while hydroxyl group at C-4' of quercetin had priority to form hydrogen bonds. During co-gelatinization process, more single helixes were induced in MS by CA than Qu or EGCG did.

Changing the Landscape: An Introduction to the Agricultural and Food Chemistry Technical Program at the 258th American Chemical Society National Meeting in San Diego.

This special issue of the Journal of Agricultural and Food Chemistry (JAFC) is a highlight of the Agricultural and Food Chemistry Division (AGFD) technical program at the 258th National Meeting of the American Chemical Society (ACS) in San Diego, CA, U.S.A., on August 25-29, 2019. At the conference, AGFD had 44 oral sessions at 19 symposia and 100 poster presentations with more than 400 abstract submissions. The technical program covered a broad range of current research and development topics in agricultural and food chemistry, including bioactive food components, diet and human nutrition, utilization of agricultural materials in food systems, food packaging, nanotechnology, and food safety, as well as several special award symposia. This is the first JAFC special issue that highlights an ACS national meeting program with joint efforts from AGFD.

Overexpression of ribonucleotide reductase small subunit, RNRM, increases cordycepin biosynthesis in transformed Cordyceps militaris.

Cordycepin was the first adenosine analogue used as an anticancer and antiviral agent, which is extracted from Cordyceps militaris and hasn't been biosynthesized until now. This study was first conducted to verify the role of ribonucleotide reductases (RNRs, the two RNR subunits, RNRL and RNRM) in the biosynthesis of cordycepin by over expressing RNRs genes in transformed C. militaris. Quantitative real-time PCR (qRT-PCR) and western blotting results showed that the mRNA and protein levels of RNR subunit genes were significantly upregulated in transformant C. militaris strains compared to the control strain. The results of the HPLC assay indicated that the cordycepin was significantly higher in the C. militaris transformants carrying RNRM than in the wild-type strain, whereas the RNRML was preferentially downregulated. For the C. militaris transformant carrying RNRL, the content of cordycepin wasn't remarkably changed. Furthermore, we revealed that inhibiting RNRs with Triapine (3-AP) almost abrogated the upregulation of cordycepin. Therefore, our results suggested that RNRM can probably directly participate in cordycepin biosynthesis by hydrolyzing adenosine, which is useful for improving cordycepin synthesis and helps to satisfy the commercial demand of cordycepin in the field of medicine.

Synbiotic Effect of Whole Grape Seed Flour and Newly Isolated Kefir Lactic Acid Bacteria on Intestinal Microbiota of Diet-Induced Obese Mice.

Alterations of intestinal microbiota by synbiotic action of pre- and probiotics may confer health benefits to the host. In this study, high-throughput sequencing of 16S rRNA was used to analyze intestinal microbiota in feces, and the relative abundance of intestinal bacteria was correlated with physiological data from a prior study of a synbiotic combination of flavonoid-rich wine grape seed flour (WGF) and two newly isolated kefir lactic acid bacteria (LAB) in diet-induced obese mice. The combination of WGF and LAB enhanced observed operational taxonomic units and Chao1 index compared to WGF alone, indicating an increase in the microbial community richness. The combination significantly enhanced abundance of Akkermansia muciniphila and Nocardia coeliaca and their abundance had an inverse relationship with body weight gain and adipose weight. In conclusion, the synbiotic effects of WGF and LAB on improvement of high-fat-diet-induced obesity are strongly linked to remodeling intestinal microbiota.

Chemistry of Pterostilbene and Its Metabolic Effects.

Pterostilbene, 3',5'-dimethoxy-4-hydroxystilbene, is a resveratrol analogue and has been reported to have similar and often potent health-promoting properties. Pterostilbene has been shown to reduce weight gain, liver fat, plasma cholesterol, adiposity, inflammatory biomarkers, blood glucose, and other physiological characteristics of metabolic diseases in animal models. Studies on pterostilbene suggest that it may improve risk factors associated with diabetes, cardiovascular disease, fatty liver diseases, Alzheimer's disease, and other neurodegenerative diseases. Many of the extensive studies on the potential health benefits of pterostilbene were conducted by Dr. Agnes Rimando, a scientist with the United States Department of Agriculture, in collaboration with many U.S. and other international research groups. This review highlights the pterostilbene research of Dr. Rimando.

Effects of Rice with Different Amounts of Resistant Starch on Mice Fed a High-Fat Diet: Attenuation of Adipose Weight Gain.

Increasing the amount of resistant starch (RS) in the diet may confer protective effects against chronic diseases. Rice, a good dietary source of carbohydrates, also contains RS. However, it remains unclear if RS at the amount consumed in cooked rice has a health benefit. To address the question, we examined the effects of cooked rice containing different levels of RS in a diet-induced obesity rodent model. Rice containing RS as low as 1.07% attenuated adipose weight and adipocyte size gain, induced by a moderately high-fat (HF) diet, which correlated with lower leptin levels in plasma and adipose tissue. Rice with 8.61% RS increased fecal short-chain fatty acid levels, modulated HF-diet-induced adipose triacylglycerol metabolism and inflammation-related gene expression, and increased fecal triglyceride excretion. Hence, including rice with RS level at ≥1.07% may attenuate risks associated with the consumption of a moderately HF diet.

Levels of Fecal Procyanidins and Changes in Microbiota and Metabolism in Mice Fed a High-Fat Diet Supplemented with Apple Peel.

The potential for apple peels to mitigate the deleterious effects of a high-fat diet in mice was investigated here. Mice were fed a high-fat diet supplemented with apple powders from three apple varieties or a commercial apple polyphenol. Polyphenols were characterized using colorimetric assays and high-performance liquid chromatography. Mice were tested for standard metabolic parameters. There was a dose response to dietary apple peels, with the higher intake leading to reduced weight gain and adipose tissue mass relative to the lower intake, but none of the treatments were statistically different from the control. The gene expression of liver enzyme stearoyl-CoA desaturase (Scd-1) was correlated with adipose weight, and liver enzyme cytochrome P51 (Cyp51) was downregulated by the apple diets. The feces from a subset of mice were analyzed for polyphenols and for bacteria taxa by next-generation sequencing. The results revealed that the makeup of the fecal microbiota was related to the metabolism of dietary polyphenols.

Hypocholesterolemic Effects of Expeller-Pressed and Solvent-Extracted Fruit Seed Oils and Defatted Pomegranate Seed Meals.

Consumptions of fruit seed oils and meals could potentially improve cardiovascular health by reducing plasma total cholesterol and low-density lipoprotein (LDL). The study objective was to compare the effectiveness of expeller-pressed and solvent-extracted grape, tomato, pomegranate seed oils, and defatted pomegranate meals in lowering plasma and hepatic cholesterol using hamster models. Hamsters were fed with fruit seed oils (FSO), defatted pomegranate seed meals (PDM), or control diets. After a 3-week feeding period, plasma total triglycerides of treatment diets were significantly lower. FSO also reduced total, very-low-density lipoprotein- (VLDL), and LDL-cholesterols, while PDM only lowered VLDL-cholesterols. Decreases in low-density and high-density lipoproteins (LDL/HDL) ratios were also observed in most treatments. In liver, triglycerides, total, and free cholesterol levels did not vary between control and treatments. There were no significant differences in lipid modulating properties between solvent-extracted and expeller-pressed oils. In conclusion, partial replacements of saturated fat in high-fat diets with tomato, pomegranate, and grape seed oils could effectively reduce plasma triglyceride levels and improve HDL/LDL ratios.