Investigating the potential of yacon (Smallanthus sonchifolius) juice in the development of organic apple-based snacks.

This study investigates the potential of yacon (Smallanthus sonchifolius) juice for the development of prebiotic-rich organic apple-based snacks. Yacon syrup, primarily composed of fructan, inulin, fructooligosaccharides (FOS), and free sugars, represents a promising nutraceutical product. Its great potential in food processing, particularly as an innovative source of prebiotics, has been demonstrated both in vitro and in vivo since it is fermented specifically by lactobacilli and bifidobacteria. Our objective was to explore the feasibility of employing vacuum impregnation process to incorporate yacon juice into organic apples, followed by hot air drying for the formulation of dried organic apple-based snacks with health-enhancing attributes. We assessed the prebiotic and physicochemical characteristics of the impregnated snacks, also considering 50 days of storage at room temperature. Vacuum impregnation and air drying produced dried apple slices impregnated with yacon juice with good quality and stability. Higher levels of fructan (16-fold difference compared to non-impregnated apples) in the apple slices increased their prebiotic potential, promoting the growth and viability of cells within simulated intestinal fluid, including strains of Bifidobacterium animalis subsp. lactis BB -12, Bifidobacterium breve DSM 20091, Bifidobacterium longum subsp. infantis DSM 20088, Lacticaseibacillus rhamnosus GG and Lacticaseibacillus rhamnosus C112, even after prolonged storage. Remarkably, the physicochemical parameters of the impregnated and dried apple slices remained nearly constant and akin to the control samples. Therefore, the combination of vacuum impregnation and air drying has the potential to be used to produce enriched prebiotic organic apple snacks, providing consumers with additional health benefits, including enhanced gut health, with its associated implications, and increased satiety. This innovation could contribute to the development of health-promoting food products with improved nutritional profiles.

Effects of Smallanthus sonchifolius Flour on Metabolic Parameters: A Systematic Review.

Smallanthus sonchifolius, popularly known as yacon, is a member of the Asteraceae family. Due to its medicinal and edible value, yacon is consumed by different populations. Yacon is unique due to its high fructo-oligosaccharide and inulin content, as well as flavonoids, sesquiterpene lactones, and phenolic acids. Roots can be used to produce flour, which is less perishable and can be applied in various industrial products. This systematic review focuses on the effects of yacon flour on metabolic parameters. PubMed, Cochrane, Embase, Science Direct, Scopus, Web of Science, and Google Scholar databases were consulted, and PRISMA guidelines were followed in the selection of the studies. In total, 526 articles were found in the databases, and of these, only 28 full texts were eligible for inclusion. After applying the inclusion and exclusion criteria, seven studies were finally included. The results showed that the use of yacon flour can reduce glycemia, HbA1c, advanced glycation ends, plasma lipids, body fat mass, body weight, and waist circumference and improve intestinal microbiota and the antioxidant status. Further exploration of the effects of yacon flour is warranted, and additional clinical trials are necessary to determine the optimal daily consumption levels required to assist in improving metabolic parameters.

Improved Bacterial Survival and Antioxidant Activity After In Vitro Digestion of Fermented Dairy Beverages by Lacticaseibacillus casei LC-01 and Lactiplantibacillus plantarum BG-112 Containing Yacon.

The fermentation of milk containing 0%, 3%, 6%, and 9% (w/v) yacon root flour (YRF) by Lacticaseibacillus casei LC-1 and Lactiplantibacillus plantarum BG-112 was evaluated for bacterial survival and antioxidant activity (AA) before and after simulated gastrointestinal digestion. After 28 days of refrigerated storage, samples of the beverages were analyzed for cell viability, AA (using ferric ion reducing antioxidant power (FRAP) and (ABTS), and molecular mass profile of proteins (using electrophoresis). The presence of 9% YRF increased bacterial survival during 28 days of storage and passage through the gastrointestinal tract for both L. casei and L. plantarum, which showed a greater capacity to reduce ferric ions compared to 0% YRF, and the ability to capture free radicals increased from below 5 mM to over 15 mM TE after digestion. Milk proteins are hydrolyzed during digestion, and the generation of bioactive peptides with AA may explain the increase in AA levels. Since peptides are generated from milk proteins, YRF did not influence AA after digestion. These results showed that fermentation of milk by L. casei and L. plantarum with YRF increased the chances of these bacteria reaching the colon in adequate quantities. After simulated digestion, the beverages showed improved AA due to milk protein hydrolysis.

Consumption of yacon flour and energy-restricted diet increased the relative abundance of intestinal bacteria in obese adults.

Prebiotics can alter the gastrointestinal environment, favoring the growth of health-promoting bacteria. Although yacon is a functional food, with prebiotic properties (fructooligosaccharides), its effects on the intestinal microbiota have not been investigated yet. The objective of this study was to evaluate the effects of yacon flour consumption and energy-restricted diet in the intestinal microbiota in adults with excess body weight. Twenty-one adults with excess body weight were included in this randomized, parallel, double-blind, placebo-controlled, 6-week clinical trial. Subjects daily consumed at breakfast a drink containing 25 g of yacon flour (n = 11) or not containing yacon (n = 10) and received the prescription of energy-restricted diets. Fecal samples were collected on the first and on last day of the study. 16S rRNA sequencing was assessed to evaluate the effect of yacon fermentation on intestinal microbiota bacterial composition. There was an increase in the genera Bifidobacterium, Blautia, Subdoligranulum, and Streptococcus after the consumption of yacon and energy-restricted diet. In the yacon group, we also observed a positive correlation between the concentrations of short-chain fatty acids versus the genera Coprococcus and Howardella, besides a negative correlation between the concentrations of advanced glycation end products and early glycation products versus the genera Ruminococcus and Prevotella, respectively. Consumption of yacon flour and energy-restricted diet selectively changed the intestinal microbiota composition in adults with excess body weight. TRIAL REGISTRATION: Register number: RBR-6YH6BQ. Registered 23 January, 2018.

Desarrollo de un endulzante natural a base de yacón (Smallanthus sonchifolius) y su evaluación sensorial / Development of a natural sweetener based on yacon (Smallanthus sonchifolius) and its sensory evaluation

Fundamentos: El yacón se considera un producto prometedor que puede posicionarse en el mercado dealimentos funcionales, dado su valor nutricional representado principalmente por su alto contenido defructooligosacáridos. La obtención de un sirope de yacón agrega valor a esta materia prima, incentivando suproducción y consumo, no solo como endulzante de mesa, sino como materia prima para la industria e inclusocomo alimento funcional. El objetivo de este trabajo fue estandarizar las condiciones para la elaboración deun sirope de yacón, y mediante análisis sensorial realizar su descripción y valoración organoléptica.Métodos: Se definieron las condiciones para la obtención de sirope de yacón y se evaluó mediante pruebasdescriptivas y afectivas en un análisis sensorial con evaluadores semi entrenados.Resultados: Con un rendimiento de cerca del 10,0% a partir de yacón fresco, se obtuvo un sirope con 65°Brixy aspecto similar a la miel, en el que se destacaron aromas a miel, propóleos y caramelo. En las pruebasafectivas, utilizando una escala hedónica de cinco puntos, las mayores valoraciones fueron para los atributoscolor 4,8 ± 0,6 y textura 4,5 ± 0,7 y la menor para el sabor 3,2 ± 1,0.Conclusiones: Las características sensoriales y su aceptabilidad proyectan el sirope de yacón como un potencialalimento funcional comercializable. (AU)

Background: Yacon is considered a promising product that can be positioned in the functional food market,given its nutritional value represented mainly by its high FOS content. Obtaining a yacon syrup adds value tothis raw material, encouraging its production and consumption, not only as a table sweetener, but also as a rawmaterial for the industry. The objetive was to standardize the conditions for the elaboration of a yacon syrup,and through sensory analysis to carry out its description and organoleptic evaluation.Methods: The conditions for obtaining yacon syrup were defined. And it was evaluated through descriptiveand affective tests in a sensory analysis with semi-trained evaluators.Results: With a yield of close to 10.0% from fresh yacon, a syrup with 65°Brix and an appearance similar tohoney was obtained, in which aromas of honey, propolis and caramel stand out. In the affective tests, using afive-point hedonic scale, the highest evaluations were for the attributes color 4.8 ± 0.6 and texture 4.5 ± 0.7and the lowest for flavor 3.2 ± 1.0.Conclusions: The sensory characteristics and its acceptability project yacon syrup as a potentially marketable functional food. (AU)

Complete chloroplast genome and phylogenetic analysis of Smallanthus sonchifolius (Asteraceae).

Smallanthus sonchifolius (Asteraceae), is an important food plant in the world. There is no systematic report on the chloroplast genome of S. sonchifolius. Here we reported its complete chloroplast genome and analyzed the basic characteristics. The chloroplast genome was 152,301 bp in length, had a GC content of 37.55%, and encoded 113 unique genes, including 79 protein-coding genes, 4 ribosomal RNA genes, and 30 transfer RNA genes. Phylogenetic analysis showed that the tribe Millerieae and the tribe Madieae are closely related in the Asteraceae family. In the tribe Millerieae, Smallanthus was more closely related to Guizotia and Sigesbeckia. This chloroplast genome not only enriches the genome information of Smallanthus, but also lays the foundation for understanding the phylogeny within the genus Smallanthus.

Quantification of Enhydrin and Uvedalin in the Ethanolic Extract of Smallanthus sonchifolius Leaves Validated by the HPLC Method.

Yacon leaf (Smallanthus sonchifolius, Asteraceae) ethanolic extracts are widely used in herbal medicine preparation for diabetes. They contain two sesquiterpene lactones (enhydrin (1) and uvedalin (2)) as major bioactive compounds. To provide a suitable method of analysis for the extract's quality control, we developed and validated a simultaneous HPLC-UV method using the compounds as markers. Compounds 1 and 2 were isolated using a freeze crystallization technique followed by a preparative HPLC. Spectrometry data for 1 and 2 were determined and compared to the literature. Chromatographic separation was carried out for 30 min with a mobile phase that used 60% water and 40% acetonitrile and a C18 column (250 × 4.6 mm, 5 µm) as the stationary phase. The flow was set to 1 mL min-1 and detection was conducted at 210 nm. The validation method was conducted according to the ICH guidelines, which included linearity, precision, accuracy, LOD, and LOQ. The calibration curve of both compounds was linear (R 2 > 0.9999), with the limit of detection and quantification as follows, respectively, 0.52 and 1.57 µg/mL for 1, and 0.144 and 0.436 µg/mL for 2. The percentages of recovery and repeatability (%RSD) were, 101.46 and 0.30% for 1, and 97.68 and 0.08% for 2, respectively. The 1 and 2 were 1.67 and 0.88% in the Ykal extract, and 1.26 and 0.56% in the Ycin extract, respectively. The method was found to be linear, precise, accurate, and suitable to be applied for control quality analyses of yacon leaf extract.

Chemical profile and toxicogenetic safety assessment of Smallanthus sonchifolius (yacon) organic extracts.

The interest in Smallanthus sonchifolius (yacon) has strongly resurfaced due to its multiple beneficial effects on human health. This study aimed at determining the toxicity and the chemical profile of an ethanol extract (EE) and a crude lactone mixture (CLM) of yacon leaves. Cytotoxicity and genotoxicity tests were performed by the MTT assay and the alkaline version of the comet assay respectively. The phytochemical analysis, performed by chromatographic and spectroscopy techniques, revealed the presence of nine sesquiterpene lactones (STLs) and two acyclic diterpene acids. In all cases, cell viability was inversely proportional to the extract concentration employed. The effects obtained with the highest dose of EE were significantly different from those obtained with the negative and solvent controls. Conversely, no significant differences were observed between the lowest doses of EE and controls. As for CLM, all tested doses showed statistically significant increases, as compared to negative and solvent controls.

Impacto del helado dietético con yacón (Smallanthussonchifolius) en la hipoglicemia y aceptabilidad / Impact of dietary ice cream with yacon (Smallanthus sonchifolius) on hyperglycemia and acceptability

Introducción: Los helados, tienen un alto contenido azúcares en su composición, por lo que es un producto interesante para estudiar alternativas en la sustitución de la misma. El yacón (Smallanthus sonchifolius) es conocida como una fuente abundante de fructooligosacáridos (FOS), inulina y compuestos fenólicos, a los cuales se les aduce importantes beneficios nutricionales y efectos en la salud. Objetivo: Evaluar el efecto hipoglucemiante, parámetros biológicos y perfil sensorial de helados formulados con sustitución de azúcar (AZ) por jarabe de yacón (JY) (Smallanthus sonchifolius). Materiales y métodos: Se desarrollaron cuatro formulaciones denominadas: T0 (100% AZ), T3 (100% JY), T1 (50:50; AZ:JY) y el T2 (25:75, AZ:JY). Se analizaron niveles de glucosa, parámetros de evaluación biológica y un perfil sensorial. Asimismo, se realizó un análisis proximal del mejor tratamiento. Resultados y discusiones: Se encontraron diferencias significativas (p<0,05) en los niveles de glucosa, siendo el T3 el cual mostro una mayor variación (disminuyo en 18,3 ml/dL). Su composición proximal tuvo una humedad de 72,50 ± 0,32%, proteína bruta 4,00 ± 0,26%, grasa bruta 2,40 ± 0,07%, cenizas 1,46 ± 0,09%, y carbohidratos 19,60 ± 0,27%. Asimismo, todos los helados mostraron un alto valor biológico (VB: 98), digestibilidad aparente (DA: 98%) y retención neta de proteína (NPR: 3,25). Finalmente, el perfil sensorial fue similar en todos los tratamientos evaluados. Conclusiones: El helado T3 (100 % jarabe de yacón) tuvo importantes resultados en el efecto hipoglucemiante, parámetros biológicos y perfil sensorial.(AU)

Introduction: Ice cream has a high sugar content in itscomposition, making it an interesting product to study alter-natives for its substitution. Yacon (Smallanthus sonchifolius)is known as an abundant source of fructooligosaccharides (FOS), inulin and phenolic compounds, which have importantnutritional benefits and health effects. Aim: To evaluate the hypoglycemic effect, biological pa-rameters and sensory profile of ice cream formulated withsugar substitution (AZ) by yacon syrup (JY) (Smallanthussonchifolius)Materials & methods: Four formulations were devel-oped: T0 (100% AZ), T3 (100% JY), T2 (50:50; AZ:JY) andT3 (25:75, AZ:JY). Glucose levels, biological evaluation pa-rameters and a sensory profile were analyzed.). Results and discussions: Significant differences (p<0,05)were found in glucose levels, with T3 showing the greatestvariation (decreased by 18,3 ml/dL). Its proximal compositionhad a moisture content of 72,50 ± 0,32%, crude protein 4,00± 0,26%, crude fat 2,40 ± 0,07%, ash 1,46 ± 0,09%, and car-bohydrates 19,60 ± 0,27%. Likewise, all ice creams showedhigh biological value (BV: 98), apparent digestibility (AD: 98%)and net protein retention (NPR: 3.25). Finally, the sensory pro-file was similar in all the treatments evaluated. Conclusions: T3 (100% JY) showed significant results inhypoglycemic effect, biological parameters and sensory profile.(AU)

The genomes of chicory, endive, great burdock and yacon provide insights into Asteraceae palaeo-polyploidization history and plant inulin production.

Inulin is an important reserve polysaccharide in Asteraceae plants, and is also widely used as a sweetener, a source of dietary fibre and prebiotic. Nevertheless, a lack of genomic resources for inulin-producing plants has hindered extensive studies on inulin metabolism and regulation. Here, we present chromosome-level reference genomes for four inulin-producing plants: chicory (Cichorium intybus), endive (Cichorium endivia), great burdock (Arctium lappa) and yacon (Smallanthus sonchifolius), with assembled genome sizes of 1.28, 0.89, 1.73 and 2.72 Gb, respectively. We found that the chicory, endive and great burdock genomes were shaped by whole genome triplication (WGT-1), and the yacon genome was shaped by WGT-1 and two subsequent whole genome duplications (WGD-2 and WGD-3). A yacon unique whole genome duplication (WGD-3) occurred 5.6-5.8 million years ago. Our results also showed the genome size difference between chicory and endive is largely due to LTR retrotransposons, and rejected a previous hypothesis that chicory is an ancestor of endive. Furthermore, we identified fructan-active-enzyme and transcription-factor genes, and found there is one copy in chicory, endive and great burdock but two copies in yacon for most of these genes, except for the 1-FEH II gene which is significantly expanded in chicory. Interestingly, inulin synthesis genes 1-SST and 1-FFT are located close to each other, as are the degradation genes 1-FEH I and 1-FEH II. Finally, we predicted protein structures for 1-FFT genes to explore the mechanism determining inulin chain length.

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.

Chemical Components and Pharmacological Activities of Smallanthus sonchifolius （Yacon）：A Review / 中国实验方剂学杂志

Smallanthus sonchifolius， a plant resource with both medicinal and edible values， has been taken as fruit for a long history. Studies have proved that phenolic acids， flavonoids， sesquiterpene lactones， and fructooligosaccharides are the major compounds in S. sonchifolius. The extract of S. sonchifolius demonstrates noticeable antioxidant， anti-inflammatory， antimicrobial， and anti-cancer effects， as well as the activities of lowering blood glucose level， regulating intestinal function and so on. The rhizomes and leaves of S. sonchifolius contain abundant phenolic acids， mainly caffeic acid and its derivatives， which endow S. sonchifolius with remarkable antioxidant effect. Moreover， these substances can reduce blood glucose by improving insulin sensitivity. Fructooligosaccharides are abundant in the tuber of this plant， which can improve intestinal function by regulating intestinal flora. The sesquiterpene lactones in glandular trichomes on the leaf surface can inhibit the proliferation of cancer cells， among which uvedafolin and enhydrofolin have particularly strong activities. Furthermore， the sesquiterpene lactones have obvious inhibitory effect on Gram-positive bacteria. In terms of structure， the number of epoxy groups is linked to the strength of anticancer and antimicrobial effects. In addition， S. sonchifolius contains other compounds such as volatile oils， fatty acids， sterols， diterpenes， p-hydroxyacetophenone derivatives， and octulosonic acid derivatives， thereby exhibiting the pharmacological effects of treating Alzheimer's disease， protecting kidney， and lowering blood lipids. However， the isolation and identification of the main compounds in S. sonchifolius need further exploration， and the mechanism of action remains to be studied. Here we summarized the principal chemical components and pharmacological activities of S. sonchifolius， aiming to give a clue for the comprehensive development and utilization of this plant.

Medicinal Plants Galega officinalis L. and Yacon Leaves as Potential Sources of Antidiabetic Drugs.

Hypoglycemic and antioxidant properties of extracts of medicinal plants Galega officinalis L. (aboveground part) and yacon (Smallanthus sonchifolius Poepp. & Endl.) (leaves) as potential sources of biologically active substances with antidiabetic action have been studied. The pronounced hypoglycemic effect of Galega officinalis extract, devoid of alkaloids, at a dose of 600 mg/kg in experimental diabetes mellitus (DM) has been proven. The established effect is evidenced by a decrease in the concentration of glucose and glycosylated hemoglobin in the blood, increase glucose tolerance of cells, increase C-peptide and insulin content in the plasma of rats' blood. The effective hypoglycemic effect of the extract in the studied pathology was confirmed by histological examination of the pancreas. The cytoprotective effect of the studied extract on pancreatic cells at a dose of 1200 mg/kg was experimentally confirmed. In the standard cut area, an increase was found in the number of Langerhans islets, their average area, diameter, volume, and a number of ß-cells relative to these indicators in animals with diabetes. Comparative screening of the antioxidant properties of 30, 50, 70, and 96% water-ethanol extracts of yacon indicates the highest potential of 50% water-ethanol extract to block free radicals in in vitro model experiments. The non-alkaloid fraction of Galega officinalis extract showed moderate antioxidant activity and was inferior to yacon extract in its ability to neutralize reactive oxygen species (ROS) and bind metal ions of variable valence. The level of antioxidant potential of the studied extracts is due to differences in the quantitative content of compounds of phenolic nature in their compositions. The obtained data on the biological effects of Galega officinalis extract on the structural and functional state of ß-cells of the pancreas and antioxidant properties of Galega officinalis and yacon extracts substantiate the prospects of using these plants to create antidiabetic medicines and functional foods based on them.

Yacon as an alternative host plant for Encarsia formosa mass-rearing: validating a multinomial theorem for bootstrap technique in life table research.

BACKGROUND: Yacon (Smallanthus sonchifolius) is a broadleaf host plant suitable for rearing the greenhouse whitefly, Trialeurodes vaporariorum (Westwood). Here, the possibility of using yacon as an alternative host plant for production of the parasitoid, Encarsia formosa Gahan, one of the most important natural enemies of whiteflies, was explored. Data on the demographic characteristics, parasitism rate, and host-feeding rate were collected and analyzed using the TWOSEX-MSChart, CONSUME-MSChart, and TIMING-MSChart computer programs, and then contrasted with comparable data from the more commonly utilized host plant, tobacco. RESULTS: Higher fecundity (F) (190.13 eggs/female) and more oviposition days (Od ) (16.60 days) were observed in E. formosa when yacon was used as the host plant for rearing T. vaporariorum, compared with when tobacco was used (F = 150.13 eggs/female, Od = 15.27 days). The intrinsic rate of increase (r), finite rate of increase (λ), and net reproduction rate (R0 ) were significantly higher in E. formosa parasitizing T. vaporariorum reared on yacon compared with those parasitizing tobacco-reared T. vaporariorum. Furthermore, the net host-feeding rate (C0 = 40.87 prey/parasitoid), net killing rate (Z0 = 239.73 prey/parasitoid), and finite killing rate ( υ = 0.2560/day) for E. formosa on yacon-reared whiteflies were significantly higher than those from tobacco-reared whiteflies. CONCLUSION: Our results showed that yacon is more suitable than tobacco as a host plant for mass-rearing E. formosa for biological control programs to manage whiteflies. An innovative application of the multinomial theorem for calculating the exact probability of bootstrap samples in life table research was also introduced. © 2021 Society of Chemical Industry.

Refrigerated storage period of Rhizophores for Yacon propagation / Períodos de armazenamento refrigerado de rizóforos para propagação de yacon

The yacon plant produces tuberous roots, used mostly for fresh consumption. This crop is propagated primarily via vegetative structures, called rhizophores. However, since these propagules have short periods of viability after harvest, storing them in cold chamber conditions may be a viable alternative to optimize yacon seedling production. The objective of this study was to test the effect of the refrigerated storage period of yacon rhizophores on seedling development. The experimental design was completely randomized, with eight replications, containing 30 useful plants per replication. Treatments were cold storage periods of propagative materials (35, 28, 21, 14, and 7 days) and a control (planting without storage). The results show that keeping rhizophores in cold storage under temperatures of 8 ºC (± 2 ºC) for a period between 21 to 35 days improves sprouting rates (speed and vigorousness), reducing seedling mortality and favoring initial yacon growth. The refrigerated storage for 21 and 35 days proved to be an alternative to achieve improved plant stand in production fields, reflecting in more uniform harvest, and minimizing the problem of seasonal availability of propagative material.Yacon, is known for its tuberous roots, which are consumed as functional food and is propagated mostly in the vegetative form, via propagules, so-called rhizophores. However, they are organs with little durability in its propagation form. Storing them in cold chamber conditions, can be a viable alternative for the seedlings production of the culture. The objective of this study was to verify the influence of the refrigerated storage period of yacon rhizophores in the initial plant development. The experimental design was completely randomized with eight replicates and six treatments and the rhizophores were place in the refrigerated storage for: 7, 14, 21, 28 and 35 days; and time zero (planting without storage). The results show that the rhizophores in the refrigerated storage in a temperature of 8 to 10°C, for a period between 21 to 35 days had better sprouting rate (speed and vigor), reducing mortality, which favored the initial yacon growth. The refrigerated storage between 21 and 35 days showed to be an alternative that resulted in a uniform plant stand in crops, also reflecting the uniformity in the harvest, and minimizes the problem of seasonality offering culture propagation material.

A yacon, conhecida por suas raízes tuberosas, que são consumidas como alimento funcional, é propagada em sua maioria na forma vegetativa, via propágulos, assim chamados de rizóforos. No entanto, são órgãos de pouca durabilidade na sua forma propagativa. Logo, o armazenamento dos mesmos em condições de câmara fria, pode vir a ser uma alternativa viável para a produção de mudas da cultura. Assim, objetivou-se com o presente trabalho, verificar a influência do período de armazenamento refrigerado dos rizóforos de yacon no desenvolvimento inicial das plantas. O delineamento experimental foi inteiramente casualizado com oito repetições e seis tratamentos constituídos pelos períodos de armazenamento refrigerado em que os rizóforos foram submetidos: 7, 14, 21, 28 e 35 dias; e o tempo zero (plantio sem armazenamento). Os resultados demonstraram que o armazenamento refrigerado dos rizóforos, em temperatura de 8 a 10 ºC, por um período entre 21 a 35 dias, proporcionou melhores índices de brotação (velocidade e vigorosidade), diminuindo a taxa de mortalidade, o que favoreceu o crescimento inicial da yacon. O armazenamento refrigerado entre 21 e 35 dias apresentou ser uma alternativa que resultou em maior uniformidade na formação do estande de plantas na lavoura, inclusive repercutindo na uniformidade de colheita, além de minimizar o problema de sazonalidade da oferta de material propagativo da cultura.

Extraction of Inulin from Andean Plants: An Approach to Non-Traditional Crops of Ecuador.

Inulin is a polysaccharide of fructose widely used in the food and pharmaceutical industry due to its physicochemical properties and technological applications. Inulin from jicama (Smallanthus sonchifolius) and cabuya (Agave americana) was obtained. The steps for inulin obtention were: raw material preparation, extraction and purification. The extraction conditions were determined using a random design with three levels of stirring speed (0, 130 and 300 rpm), and a 32 factorial experimental design with three levels of temperature (40, 60 and 80 °C) and solid:liquid ratio (1:2, 1:3 and 1:5 S:L). The results showed that the best extractions conditions for jicama were 130 rpm, 75 °C, 1:5 S:L and 25 min; while for cabuya were 80 °C, 300 rpm, 1:5 S-L and 100 min. The weight average molecular weight of inulin from jicama and cabuya were 5799.9 and 4659.75 g/mol, respectively. The identity of the obtained inulin from jicama and cabuya were confirmed by infrared (IR) and Raman spectroscopy. In addition, scanning electron microscopy, differential scanning calorimetry and thermogravimetry analyses were performed to characterize both inulins.

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.

Chemical Defense of Yacón (Smallanthus sonchifolius) Leaves against Phytophagous Insects: Insect Antifeedants from Yacón Leaf Trichomes.

Yacón is a perennial crop with high insect resistance. Its leaves have many glandular trichomes, which may be related to pest resistance. In order to collect the constituents of glandular trichomes, leaves were rinsed using dichloromethane (DCM) to obtain the rinsate, and the plant residues were subsequently extracted by DCM to obtain a DCM extract containing the internal constituents of yacón leaves. Biologic evaluations revealed that insect antifeedant activity was stronger for the rinsate than for the DCM extract against the common cutworm. The major constituents of rinsate were isolated by silica gel flash chromatography and were identified as sesquiterpene lactones (SLs), uvedalin (1) and enhydrin (2) and uvedalin aldehyde (3), collectively known as melampolides. Although SLs 1 and 2 exhibited remarkably strong insect antifeedant activity, SL 3 and reduced corresponding derivatives (4 and 5) of 1 and 2 exhibited moderate insect antifeedant activity. Additionally, the two analogs, parthenolide (6) and erioflorin (7) showed moderate insect antifeedant activity. The results indicate that the substituent patterns of SLs may be related to the insect antifeedant activities. The insect antifeedant activities of SLs 1 and 2 were similar to that of the positive control azadirachtin A (8), and thus these natural products may function in chemical defense against herbivores.

Metabolomic and Gene Expression Studies Reveal the Diversity, Distribution and Spatial Regulation of the Specialized Metabolism of Yacón (Smallanthus sonchifolius, Asteraceae).

Smallanthus sonchifolius, also known as yacón, is an Andean crop species commercialized for its nutraceutical and medicinal properties. The tuberous roots of yacón accumulate a diverse array of probiotic and bioactive metabolites including fructooligosaccharides and caffeic acid esters. However, the metabolic diversity of yacón remains unexplored, including the site of biosynthesis and accumulation of key metabolite classes. We report herein a multidisciplinary approach involving metabolomics, gene expression and scanning electron microscopy, to provide a comprehensive analysis of the diversity, distribution and spatial regulation of the specialized metabolism in yacón. Our results demonstrate that different metabolic fingerprints and gene expression patterns characterize specific tissues, organs and cultivars of yacón. Manual inspection of mass spectrometry data and molecular networking allowed the tentative identification of 71 metabolites, including undescribed structural analogues of known bioactive compounds. Imaging by scanning electron microscopy revealed the presence of a new type of glandular trichome in yacón bracts, with a distinctive metabolite profile. Furthermore, the high concentration of sesquiterpene lactones in capitate glandular trichomes and the restricted presence of certain flavonoids and caffeic acid esters in underground organs and internal tissues suggests that these metabolites could be involved in protective and ecological functions. This study demonstrates that individual organs and tissues make specific contributions to the highly diverse and specialized metabolome of yacón, which is proving to be a reservoir of previously undescribed molecules of potential significance in human health.

The amino acid and carbohydrate composition of the herb and roots of Smallanthus sonchifolius.

The free and protein-bound amino acid composition of the herb and roots of Smallanthus sonchifolius was analyzed by HPLC method. Fourteen free and fifteen protein-bound amino acids were determined in yacon herb, and three free and fourteen protein-bound amino acids in the roots. Among the free amino acids, proline (0.44 µg/mg) and aspartic acid (0.12 µg/mg) were dominant in the herb and proline (0.28 µg/mg) in the roots. Among the protein-bound amino acids, aspartic acid (18.58 µg/mg), glutamic acid (16.33 µg/mg) and proline (14.52 µg/mg) prevailed in the herb, and proline (3.14 μg/mg) in the roots. Fructose, sucrose and arabinose were identified in free form in the herb of S. sonchifolius applying gas chromatography-mass spectrometry (GC-MS). The polysaccharide complex was obtained from yacon herb, its yield was 5.13 ± 0.09%. Fructose (3.11 µg/mg) was the only monosaccharide identified in the hydrolysate of the obtained complex.