Yaskolka, M.A., K. Tuohy K, M. von Bergen, R. Krajmalnik-Brown, U. Heinig, H. Zelicha, G. Tsaban, E. Rinott, A. Kaplan, A. Aharoni, L. Zeibich, D. Chang, B. Dirks, C. Diotallevi, P. Arapitsas, U. Vrhovsek, U. Ceglarek, S.-B. Haange, U. Rolle-Kampczyk, B. Engelmann, M. Lapidot, M. Colt, Q. Sun, I., 2021. The metabolomic-gut-clinical axis of Mankai plant-derived dietary polyphenols. Nutrients. 13(6):1866. https://doi.org/10.3390/nu13061866.
Background: Polyphenols are secondary metabolites produced by plants to defend themselves from environmental stressors. We explored the effect of Wolffia globosa ‘Mankai’, a novel cultivated strain of a polyphenol-rich aquatic plant, on the metabolomic-gut clinical axis in vitro, in-vivo and in a clinical trial. Methods: We used mass-spectrometry-based metabolomics methods from three laboratories to detect Mankai phenolic metabolites and examined predicted functional pathways in a Mankai artificial-gut bioreactor. Plasma and urine polyphenols were assessed among the 294 DIRECT-PLUS 18-month trial participants, comparing the effect of a polyphenol-rich green-Mediterranean diet (+1240 mg/polyphenols/day, provided by Mankai, green tea and walnuts) to a walnuts-enriched (+440 mg/polyphenols/day) Mediterranean diet and a healthy controlled diet. Results: Approximately 200 different phenolic compounds were specifically detected in the Mankai plant. The Mankai-supplemented bioreactor artificial gut displayed a significantly higher relative-abundance of 16S-rRNA bacterial gene sequences encoding for enzymes involved in phenolic compound degradation. In humans, several Mankai-related plasma and urine polyphenols were differentially elevated in the green Mediterranean group compared with the other groups (p < 0.05) after six and 18 months of intervention (e.g., urine hydroxy-phenyl-acetic-acid and urolithin-A; plasma Naringenin and 2,5-diOH-benzoic-acid). Specific polyphenols, such as urolithin-A and 4-ethylphenol, were directly involved with clinical weight-related changes. Conclusions: The Mankai new plant is rich in various unique potent polyphenols, potentially affecting the metabolomic-gut-clinical axis.
Lackey, K.A., S.A. Fleming, 2021. Brief research report: estimation of the protein digestibility-corrected amino acid score of defatted walnuts. Frontiers in Nutrition. 8, 702857. https://doi.org/10.3389/fnut.2021.702857
Introduction: Walnuts are considered a good source of essential fatty acids, which is unique among tree nuts. Walnuts are also composed of about 10–15% protein, but the quality of this protein has not been evaluated. Pistachios and almonds have been evaluated for their protein content using a protein digestibility-corrected amino acid score (PDCAAS), but it is unclear how the quality of protein in walnuts relates to that in other commonly consumed tree nuts. The objective of this study was to substantiate the protein quality of walnuts by determining their PDCAAS. Methods: A small, 10-day dietary intervention trial was conducted using male Sprague-Dawley rats (n = 8, 4 per group) with two diets: a nitrogen-free diet and a diet containing protein exclusively from defatted walnuts. Feed intake and fecal output of nitrogen were measured to estimate the true protein digestibility, and the amino acid compositions of walnuts compared to child and adult populations were used to calculate amino acid scores (AAS) and PDCAAS. Results: The true protein digestibility score of raw walnuts was calculated to be 86.22%. Raw walnuts contained 15.6 g protein/g walnut with AAS of 0.45 and 0.63 for children aged 6 months to 3 years and 3–10 years, respectively. For each population, a PDCAAS of 39 and 46% was calculated, respectively, using a protein conversion constant of 5.30. Using a protein constant of 6.25, a PDCAAS of 39% (6 months – 3 years) or 46% (3-10 years) was calculated. Conclusions: This is the first known assessment of the PDCAAS of walnuts. Like almonds, appear to have a low-to-moderate score, indicating they are not a quality source of protein.
Nishi, S. K., C.W.C. Kendall, R.P. Bazinet, A.J. Hanley, E.M. Comelli, D.J.A. Jenkins, J.L. Sievenpiper, 2021. Almond bioaccessibility in a randomized crossover trial: is a calorie a calorie? Mayo Clin. Proc. 96(9):2386–2397. https://doi.org/10.1016/j.mayocp.2021.01.026
Objective: To investigate the energy and macronutrient bioaccessibility of almonds in individuals with hyperlipidemia. Methods: In a previously reported randomized crossover trial, men and postmenopausal women with hyperlipidemia incorporated 3 isoenergetic supplements into a National Cholesterol Education Program Step 2 diet for 1 month each between September 20, 2000, and June 27, 2001. Supplements provided consisted of full-dose almonds (73±5 g/d), half-dose almonds (38±3 g/d) plus half-dose muffins, and full-dose muffins (control). Energy and macronutrients, including individual fatty acids, were measured in the dietary supplements and fecal samples using gas chromatography and Association of Official Analytical Chemists methods. Serum was measured for lipids and fatty acids. Bioaccessibility of energy and macronutrients from almond consumption was assessed from dietary intake (7-day food records) and fecal output. Results: Almond-related energy bioaccessibility was 78.5%±3.1%, with an average energy loss of 21.2%±3.1% (40.6 kcal/d in the full-dose almond phase). Bioaccessibility of energy and fat from the diet as a whole was significantly less with almond consumption (in both half- and full-dose phases) compared with the control. Bioaccessibility of fat was significantly different between treatment phases (P<.001) and on average lower by 5.1% and 6.3% in the half- and full-dose almond phases, respectively, compared with the control phase. Energy bioaccessibility was significantly different between the treatment phases (P=.02), decreasing by approximately 2% with the inclusion of the full dose of almonds compared with the control. Conclusion: Energy content of almonds may not be as bioaccessible in individuals with hyperlipidemia as predicted by Atwater factors, as suggested by the increased fat excretion with almond intake compared with the control.
Choo, J.M., C.D. Tran, N.D. Luscombe-Marsh, W. Stonehouse, J. Bowen, N. Johnson, C.H. Thompson, E.-J. Watson, G.D. Brinkworth, G.B. Rogers, 2021. Almond consumption affects fecal microbiota composition, stool pH, and stool moisture in overweight and obese adults with elevated fasting blood glucose: A randomized controlled trial. Nutr Res. 85:47-59.
Regular almond consumption has been shown to improve body weight management, lipid profile and blood glucose control. We hypothesized that almond consumption would alter fecal microbiota composition, including increased abundance and activity of potentially beneficial bacterial taxa in adults who are overweight and obese with elevated fasting blood glucose. A total of 69 adults who were overweight or obese with an elevated plasma glucose (age: 60.8 ± 7.4, BMI ≥27 kg/m2, fasting plasma glucose ≥5.6 to <7.0 mmol/L) were randomized to daily consumption of either 2 servings of almonds (AS:56 g/day) or an isocaloric, high carbohydrate biscuit snack for 8 weeks. AS but not biscuit snack experienced significant changes in microbiota composition (P= .011) and increases in bacterial richness, evenness, and diversity (P< .01). Increases in both the relative and absolute abundance of operational taxonomic units in the Ruminococcaceae family, including Ruminiclostridium (false discovery rate P = .002), Ruminococcaceae NK4A214 (P = .002) and Ruminococcaceae UCG-003 (P = .002) were the principal drivers of microbiota-level changes. No changes in fecal short chain fatty acid levels, or in the carriage of the gene encoding butyryl-CoA:acetate CoA-transferase (an enzyme involved in butyrate synthesis) occurred. Almond consumption was not associated with reduced gut permeability, but fecal pH (P= .0006) and moisture content (P = .027) decreased significantly in AS when compared to BS. Regular almond consumption increased the abundance of potentially beneficial ruminococci in the fecal microbiota in individuals with elevated blood glucose. However, fecal short-chain fatty acid levels remained unaltered and the capacity for such microbiological effects to precipitate host benefit is not known.
