Evaluation of nutritional and chemical composition of yacon syrup using 1H NMR and UPLC-ESI-Q-TOF-MSE

Functional effects of yacon (Smallanthus sonchifolius) and kefir on systemic inflammation, antioxidant activity, and intestinal microbiome in rats with induced colorectal cancer

Colorectal cancer (CRC) is one of the most common cancers with high morbidity and mortality. The modulation of intestinal health through the administration of pro- and prebiotics may be a viable alternative to reduce the risk of CRC. This study aimed to evaluate the functional effects of yacon and kefir, isolated or associated, in rats with colorectal cancer. Adult Wistar rats were divided into five groups (n = 8): HC (healthy control AIN-93M diet), CC (CCR + AIN-93M diet), Y (CCR + AIN-93 M + yacon diet), K (CCR + AIN-93-M + kefir diet) and YK (CCR + AIN-93 M + yacon + kefir diet). Colorectal carcinogenesis was induced in groups CC, Y, K, and YK with 1,2-dimethylhydrazine (55 mg kg-1, subcutaneously) for 5 weeks. From the 6th week onwards, the experimental groups were fed the respective diets. In the 15th week, urine was collected for analysis of intestinal permeability and then the animals were euthanized. Yacon increased acetate levels, reduced pH and carcinogenic neoplastic lesions, and increased the abundance of bacteria related to the fermentation of non-digestible carbohydrates, such as the genera Dorea, Collinsela, and Bifidobacteria. On the other hand, kefir increased macroscopic neoplastic lesions and increased the abundance of Firmicutes and Clostridium. The association of yacon + kefir increased the number of carcinogenic lesions, despite a reduction in pH and beneficial bacteria prevalence. Thus, it is concluded that yacon, unlikely kefir, is a promising alternative to mitigate the manifestations of induced carcinogenesis in rats.

Assessment of metabolic, mineral, and cytotoxic profile in pineapple leaves of different commercial varieties: A new eco-friendly and inexpensive source of bioactive compounds

Pineapple is among the most produced and consumed fruits worldwide, and consequently, its agroindustrial production/processing generates high amounts of agricultural waste, which are routinely discarded. Thus, it is crucial to seek alternatives to reuse this agricultural waste that are in high availability. Therefore, this work aims to evaluate the chemical composition of a specific residue (leaves) of seven commercial varieties of pineapples, to attribute high added value uses, and to evaluate its potential as a source of secondary metabolites and minerals. Thereby, twenty-eight metabolites were annotated by UPLC-QTOF-MS^E, including amino acids, organic acids, and phenolic compounds. The following minerals were quantitatively assessed by ICP-OES: Zn (5.30-19.77 mg kg^-1), Cr, Cd, Mn (50.80-113.98 mg kg^-1), Cu (1.05-4.01 mg kg^-1), P (1030.77-6163.63 mg kg^-1) and Fe (9.06-70.17 mg kg^-1). In addition, Cr and Cd (toxic materials) present concentration levels below the limit of quantification of the analytical method (LOQ_Cr and LOQ_Cd = 0.02 mg kg^-1) for all samples. The multivariate analysis was conceived from the chemical profile, through the tools of PCA (principal component analysis) and HCA (hierarchical cluster analysis). The results show that pineapple leaves have similarities and differences concerning their chemical composition. In addition, the cytotoxicity assays of the extracts against tumor and non-tumor strains shows that the extracts were non-toxic. This fact can corroborate and enhance the prospection of new uses and applications of agroindustrial co-products from pineapple, enabling the evaluation and use in different types of industries, such as pharmacological, cosmetic, and food, in addition to the possibility of being a potential source of bioactive compounds.

Previous gut microbiota has an effect on postprandial insulin response after intervention with yacon syrup as a source of fructooligosaccharides: a randomized, crossover, double-blind clinical trial

OBJECTIVES

The use of prebiotics has an effect on postprandial glucose and insulin concentrations; however, the interaction between the previous profile of the intestinal microbiota and the effect of supplementation with prebiotics is not clear. Our objective was to evaluate the effect of previous intestinal microbiota profile on the postprandial insulin response to yacon syrup, used as a source of fructooligosaccharides (FOSs), in young women. The product presents high levels of FOS.

METHODS

In this double-blind, crossover, randomized clinical trial, 40 adult women were allocated to receive a breakfast containing 40 g of yacon syrup (14 g FOS, intervention A) or a breakfast containing 40 g of placebo (intervention B). On each intervention day, after 12 h of fasting, an aliquot of blood was collected for insulin analysis at 0, 15, 30, 45, 60, 90, and 120 min. The fecal sample was collected before the beginning of the interventions, and the DNA was extracted and quantified, with subsequent amplification of the 16S region, next-generation sequencing, and analysis of sequencing data.

RESULTS

The glucose and insulin concentrations were reduced after ingestion of yacon syrup compared with placebo, specifically at the 30 min to insulin. After the receiver operating characteristic analysis, six volunteers who did not respond to the yacon consumption intervention were identified. The abundance of the phylum Actinobacteria (P = 0.021) and the order Bifidobacteriales (P = 0.013) were positively associated with better insulin response. Other main phyla were not associated with intervention response.

CONCLUSIONS

The previous profile of the intestinal microbiota has an effect on the postprandial insulin response to FOSs, mainly in the phylum Actinobacteria and Bifidobacteriales order.

A Comprehensive Chemical and Nutritional Analysis of New Zealand Yacon Concentrate

Global interest in yacon (Smallanthus sonchifolius) is growing due to its potential as a functional food, attributable to its unique profile of bioactives and high fructooligosaccharide (FOS) content, which vary between cultivars. Our objective was to conduct a comprehensive chemical and nutritional analysis of New Zealand yacon concentrate (NZYC)-a sweet syrup derived from the roots of cultivar 'New Zealand', which was first grown in the 1980s. The major minerals in NZYC were potassium, phosphorus, and calcium. The FOS content ranged from 17.6 to 52.7 g/100g. Total phenolic content ranged from 565 to 785 mg gallic acid equivalents per 100 g; chlorogenic acid and caffeic acid were the major phenolic compounds. The major amino acids were L-arginine, L-glutamic acid, L-proline, L-aspartic acid, and asparagine. The major organic acids were citric, malic, quinic, and fumaric acids. Antioxidant activity ranged from 1084.14 to 3085.78 mg Trolox equivalents per 100 g depending on the assay used. The glycaemic index (GI) value was 40 ± 0.22, classifying it as a low-GI food. These results support the classification of NZYC as a nutraceutical food product for future diet therapy applications.

Yacon-based product improves intestinal hypertrophy and modulates the production of glucagon-like peptide-1 in postmenopausal experimental model

AIMS

The progressive decline in estrogen level puts postmenopausal women at a higher risk of developing cardiometabolic diseases. Thus, we evaluated the potential beneficial effects of yacon-based product (YBP) on glycemic profile and intestinal health of postmenopausal rats.

METHODS

Eighty Wistar rats were randomized into 4 ovariectomized (OVX) groups or 4 celiotomized groups treated with a standard diet (SD) or diet supplemented with YBP at 6% of fructooligosaccharide (FOS)/inulin.

KEY FINDINGS

The continued consumption of YBP at 6% of FOS/inulin did not generate liver damage and gastrointestinal disorders. Rats fed with YBP displayed higher food consumption, but this did not increase the body weight gain, abdominal circumference and body fat percentual of OVX rats. Furthermore, we also found that the FOS/inulin fermentation present in the YBP resulted in cecum, ileum and colon crypts hypertrophy and increased the lactic acid levels in the cecal content. We observed an increase of glucagon-like peptide-1 (GLP-1) immunoreactive cells and there was no change in the glucose and insulin plasma levels of YBP-fed OVX rats.

SIGNIFICANCE

Our findings indicated that YBP when consumed previously and after the menopausal period has important effects on the morphology and function of intestinal mucous of rats and has potential to modulate indirectly the glycemic and insulinemic profiles, weight gain and body fat percentual in the hypoestrogenic period through metabolites produced in the fermentation process.

1 H-NMR analysis, antioxidant activity, and α-amylase and α-glucosidase inhibitory potential of ten common Thai edible flowers

BACKGROUND

Edible flowers have been used in cooking as foods as well as medicine alternatives. The objectives were to identify a major class of organic compounds in edible flowers by applying proton nuclear magnetic resonance (¹ H-NMR) metabolite fingerprinting and to evaluate bioactivity including antioxidant and α-amylase and α-glucosidase inhibitory activities.

RESULTS

A total of 32 metabolites including five organic acids, eight sugars, 11 amino acids and eight phenolic compounds were identified by using ¹ H-NMR at 600 MHz. The aromatic proton of phenolic compounds was observed at the low-field region ranged between δ 5.5 ppm and 10.0 ppm. Total phenolic content (TPC) of the extracts of edible flowers ranged from 6.0 mg GAE g^-1 dry weight (DW) to 47.97 mg GAE g^-1 DW. Antioxidant activity varied from 140.5 mmol L^-1 TE g^-1 DW to 985.2 mmol L^-1 TE g^-1 DW. The extracts from edible flowers showed dose-dependent inhibition against enzyme. The extract of African marigold (Tagetes erecta L.) had the highest half maximal inhibitory concentration (IC₅₀ ) against α-amylase at 0.13 mg mL^-1 while the extract of flower of Sesban agasta (Sesbania grandiflora Desv.) had the lowest IC₅₀ against α-amylase at 0.63 mg mL^-1 . Moderate correlation was found between IC₅₀ values against α-glucosidase and antioxidant activity values (R²  = 0.66) (P < 0.05).

CONCLUSION

¹ H-NMR application provided metabolomic fingerprinting of edible flowers and the in vitro inhibitory potential activity against key enzymes related to diabetes indicated that specific edible flowers have a potential use for dietary management during the early stages of hyperglycaemia. © 2021 Society of Chemical Industry.

Acute postprandial effect of yacon syrup ingestion on appetite: A double blind randomized crossover clinical trial

Yacon syrup is a rich source of fructooligosaccharides (FOS); however, its diet supplementation effect on subjective sensation and appetite biomarkers in human is still unknown. This study aimed to evaluate the acute postprandial effect of yacon syrup ingestion on appetite. The double-blind crossover clinical trial was carried out with 40 adult women: 20 eutrophic and 20 obese grade I. On each day, the first blood collection was performed after a 12-h fast. Then, the volunteers ingested either intervention A (breakfast + 40 g of placebo) or intervention B (breakfast + 40 g of yacon syrup, containing 14 g of FOS). New aliquots of blood were collected at 45, 60, 90, 120, and 180 min. Appetite was assessed by estimating ghrelin and glucagon-like peptide-1 (GLP-1) levels and by assessing subjective appetite sensation. Analysis was performed using two-way ANOVA, followed by Bonferroni's multiple comparison test. No effect of yacon syrup was observed on postprandial ghrelin and GLP-1 levels at all times evaluated. Similar observations were made after stratifying the analysis by BMI (body mass index) (eutrophic and obese). The effect of yacon syrup on postprandial subjective sensations of hunger, satiety, fullness, and desire to eat was not evident in the total group of women evaluated and even after BMI stratification. We concluded that yacon syrup had no effect on postprandial ghrelin and GLP-1 levels and on the subjective appetite sensation in young adult women.

Feature-Based Molecular Networking to Target the Isolation of New Caffeic Acid Esters from Yacon (Smallanthus sonchifolius, Asteraceae)

Smallanthus sonchifolius (yacon) is an edible tuberous Andean shrub that has been included in the diet of indigenous people since before recorded history. The nutraceutical and medicinal properties of yacon are widely recognized, especially for the improvement of hyperglycemic disorders. However, the chemical diversity of the main bioactive series of caffeic acid esters has not been explored in detail. In this metabolomics study, we applied the latest tools to facilitate the targeted isolation of new caffeic acid esters. Using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), we analyzed extracts from different organs (roots, vascular tissues of the stems, stem epidermis, leaves, bracts, and ray flowers) and followed a feature-based molecular networking approach to characterize the structural diversity of caffeic acid esters and recognize new compounds. The analysis identified three potentially new metabolites, one of them confirmed by isolation and full spectroscopic/spectrometric assignment using nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), and MS/MS. This metabolite (5-O-caffeoyl-2,7-anhydro-d-glycero-β-d-galacto-oct-2-ulopyranosonic acid), along with eight known caffeic acid esters, was isolated from the roots and stems. Furthermore, based on detailed tandem MS analyses, we suggest that the two isomeric monocaffeoyl-2,7-anhydro-2-octulopyranosonic acids found in yacon can be reliably distinguished based on their characteristic MS² and MS³ spectra. The outcome of the current study confirms the utility of feature-based molecular networking as a tool for targeted isolation of previously undescribed metabolites and reveals the full diversity of potentially bioactive metabolites from S. sonchifolius.

Yacon syrup reduces postprandial glycemic response to breakfast: A randomized, crossover, double-blind clinical trial

Yacon is a root rich in fructooligosaccharides (FOS), which act as prebiotics. Numerous studies have shown promising results in the technological aspects of producing yacon syrup. However, uncertainties exist concerning whether yacon syrup can modulate postprandial glucose and lipid profiles. In order to assess the effect of yacon syrup on postprandial glucose, insulin and triglyceride (TG) responses, a randomized, crossover, double-blind clinical intervention with 40 women (20 normal weight and 20 grade I obese) was performed. Participants underwent two-arms of intervention with at least a one-week wash-out period between visits. On each intervention day, after 12 h of fasting, an aliquot of blood was collected. For intervention A, volunteers consumed breakfast +40 g of placebo, whereas for intervention B, participants consumed breakfast +40 g of yacon syrup (14 g of FOS). Blood samples were drawn at 15, 30, 45, 60, 90, and 120 min. Glucose and insulin concentrations were lowered after yacon syrup intake as compared to placebo at following times: 30 min for glucose and 15, 30 and 45 min for insulin. In conclusion, yacon syrup has a postprandial decreasing effect glucose and insulin concentrations in adult women. This effect was not evident for triglyceride concentration. Clinical trial registry: RBR-33wf46. Available in: http://www.ensaiosclinicos.gov.br/rg/RBR-33wf46/.

Effect of Different Post-Harvest Processing Methods on the Chemical Constituents of Notopterygium franchetii by an UHPLC-QTOF-MS-MS Metabolomics Approach

Notopterygium franchetii is a herb used in traditional Chinese medicine, where it is known as qianghuo. Its bioactive qualities are influenced by the post-harvest processing methods used (such as drying). However, changes in chemical components according to the drying method are unknown. Fresh roots and rhizomes of N. franchetii were subjected to seven drying methods. Chromatography-mass spectrometry combined with targeted and untargeted analyses were used to investigate relationships between drying methods and chemical concentrations. According to targeted evaluations of the six main bioactive constituents, their total contents decreased significantly in all drying methods. Hierarchical clustering analysis of the drying methods and total metabolome detected 30 chemical constituents, for which heap maps were obtained. Hot air drying was the best processing method, producing the least chemical changes at the lowest cost, while shade drying caused the greatest chemical changes. In conclusion, the wide range of chemical changes in N. franchetii caused by drying was investigated. Such changes potentially affect the quality of herbal medicines.

Technological Aspects of the Production of Fructo and Galacto-Oligosaccharides. Enzymatic Synthesis and Hydrolysis

Fructo- and galacto-oligosaccharides (FOS and GOS) are non-digestible oligosaccharides with prebiotic properties that can be incorporated into a wide number of products. This review details the general outlines for the production of FOS and GOS, both by enzymatic synthesis using disaccharides or other substrates, and by hydrolysis of polysaccharides. Special emphasis is laid on technological aspects, raw materials, properties, and applications.

Sensory acceptance and characterization of yoghurt supplemented with yacon syrup and cashew apple extract as a source of bioactive compounds

Abstract Yacon syrup (YS) and cashew apple extract (CAE) are products with high concentrations of bioactive compounds such as fructooligosaccharides and carotenoids, which exhibit prebiotic and antioxidant properties. The objective of this work was to evaluate the impact of YS and CAE on the chemical, physical, physicochemical and sensory properties when these products were incorporated into natural yoghurt. Initially, the YS and CAE were characterized by chemical, physical and physicochemical analyses. The bioactive compounds, such as carotenoids, fructooligosaccharides and phenolic compounds, and the antioxidant activity were also determined. After characterization, natural yoghurt was supplemented with YS and CAE in different concentrations as follows: formulation A (non-supplemented yoghurt, as the control), formulation B (yoghurt with the addition of 20% of YS), formulation C (yoghurt with the addition of 20% of YS and 10% of CAE) and formulation D (yoghurt with the addition of 20% of YS and 20% of CAE). The formulations were evaluated for their sensory acceptance (overall acceptance, texture and appearance) and purchase intent, and were then characterized by chemical, physicochemical and physical analyses. The results indicated that the YS and CAE presented high concentrations of bioactive compounds, such as fructooligosaccharides and carotenoids, respectively. In addition, when the yoghurt was supplemented with these products, this induced changes in the chemical, physicochemical and physical properties of the yoghurt. In the sensory analysis, all the formulations presented good acceptance. The results indicated that yoghurt could be considered as an interesting vehicle for YS and CAE, products with high levels of bioactive compounds that may exert beneficial effects on human health.