Yacon Roots Research Articles

Calibration and validation of FAO-AquaCrop model to estimate the total biomass and yacon root yield

Calibration and validation of FAO-AquaCrop model to estimate the total biomass and yacon root yield

Functional activities of neutrophils in diabetic rats are changed by yacon extracts

Introduction. Characterization of the polymorphonuclear neutrophils functional activity during the diabetes is of outmost importance for the understanding of the immunological processes involved in disease pathogenesis. The search for effective drugs that would suppress and/or modulate the immune response, preferably without negative effects, is a promising area of modern research. Smallanthus sonchifolius Poepp. et Endl., which has long been used in folk medicine to treat diabetes, was proposed as a potential treatment for immune disorders. The study aimed to search for the effective drug which would be able to regulate neutrophils functional activity in experimentally induced type 1 diabetes mellitus. Material and methods. The experiments were conducted on male Wistar rats. Diabetes was induced by intraabdominal injection of streptozotocin. For the evaluation of phagocytic activity and the content of cationic proteins and myeloperoxidase in neutrophils cytochemical studies were performed. Results. Diabetes development was accompanied by reduced phagocytic activity of granulocytes and increased activity of myeloperoxidase. All used extracts intensified phagocytic activity of neutrophil in diabetes, with the yacon root tubers extract demonstrating the strongest effect, which was reflected by rapid degradation of particles engulfed by phagocytes. Conclusions. It was established that yacon extracts inhibit myeloperoxidase activity in diabetes. Therefore all investigated extracts have a pronounced immunocorrective effect and can become the basis for creating a new generation of antidiabetic drugs.

English

English

Yacon production at different planting seasons and growing environments

Yacon is a functional food with great potential for horticultural exploitation and its cultivation demands the generation of agronomic information. To address these needs, this study was performed to evaluate the production of yacon planted in different planting seasons under two growing conditions in Brazil. The experiments were conducted in two different locations, one in the mountain region (tropical microclimate at altitude with milder temperatures) and the other in the lowland region (warm tropical microclimate with higher temperatures). At both sites, yacon was planted in four seasons: autumn (April), winter (July), spring (September) and summer (December). At harvest, the tuberous roots were evaluated for leaf area index and the variables of vegetative development and productivity of plants (for total and standard commercial roots). It was concluded that yacon cultivation in mountain conditions (tropical climate with milder temperature) promotes the development and production of yacon. Additionally, planting in the autumn for both growing conditions (mountain or lowland) promotes the development and production of yacon, including increased production of roots of better commercial grade, allowing greater economic profitability. These results indicate that temperature has an influence on the growth and yield of the tuberous roots of yacon, and milder temperatures were more favourable.

UPLC-DAD-QToF/MS를 이용한 야콘(Smallanthus sonchifolius) 괴근 내 페놀산 유도체 분석

UPLC-DAD-QToF/MS를 이용한 야콘(Smallanthus sonchifolius) 괴근 내 페놀산 유도체 분석

Consumption of yacon flour improves body composition and intestinal function in overweight adults: A randomized, double-blind, placebo-controlled clinical trial

Yacon root is a natural source of fructooligosaccharides (FOS), and it has been studied for its potential effect as a functional food. However, FOS in the in natura root are rapidly hydrolyzed. Thus, the use of dehydrated products such as flour ensures stability of FOS. The effect of chronic consumption of yacon flour on body composition, food intake and of biochemical variables concentration has not yet been evaluated in humans. Thus, we evaluated the effects of yacon flour consumption on these variables associated with excess body weight. Twenty-six adults (31.3±8.5 years) with excess weight (30.4±2.4kg/m2, 40.16±6.7% body fat) participated in this randomized, double-blind, six-week study. Subjects were randomly allocated to one of the experimental groups (control (n=13) or yacon flour (n=13)), received the prescription of energy-restricted diets (- 500kcal/day) and daily consumed a breakfast drink not containing or containing 25g of yacon flour (0.1g of FOS/kg body weight). At the beginning and at the end of the study, biochemical analyses (glycemia, insulinemia, lipid profile and liver function markers), anthropometrics (weight, waist, hip and neck circumference and sagittal abdominal diameter), body composition (lean mass, total body fat, trunk fat, android fat and gynoid fat), blood pressure, intestinal function, and food intake were assessed. Daily yacon flour consumption was well tolerated, did not cause adverse gastrointestinal effects, increased dietary fiber consumption, promoted greater body weight, waist circumference, waist to height index, sagittal abdominal diameter, and body fat reduction, besides improving bowel function in comparison to the control group. Yacon flour served as a natural fiber supplement and proved to be an effective adjuvant to be used in nutritional strategies to control excess body weight.

Total Phenolic Content and Antioxidant Activity of Yacon (Smallanthus Sonchifolius Poepp. and Endl.) Chips: Effect of Cultivar, Pre-Treatment and Drying

Recent studies have associated the consumption of yacon root as a functional plant food with reduced glycemic index and, due to its considerable phenolic acid levels, a protection of cell membranes against free radical damage. This study examined the effect of four different treatments including: (1) storage duration after harvest (one and three weeks after harvest); (2) pre-treatment before drying (untreated, pre-treatment with diluted lime juice); (3) drying method (freeze drying (FD) and convective hot air drying (CHAD)); and (4) cultivar (white and red), on the quality of yacon (Smallanthus sonchifolius Poepp. and Endl.) chips in terms of their total phenolic content (TPC) and antioxidant activity (AA) (ABTS (2,2′-Azino-Bis (3-Ethylbenzothiazoline-6-Sulfonic Acid) Diammonium Salt) radical scavenging activity, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and ferric reducing antioxidant power (FRAP)). Overall, the chips that were produced using pre-treatment with diluted lime juice and FD had the highest amounts of TPC and AA. Regarding the chips produced by means of CHAD, retention of higher TPC and AA was possible with lime-juice pre-treatment and use of higher hot air temperatures. Moreover, chips produced from the white cultivar had higher TPC and AA than chips produced from the red cultivar.

Smallanthus sonchifolius (Yacon) Flour Improves Visceral Adiposity and Metabolic Parameters in High-Fat-Diet-Fed Rats.

Smallanthus sonchifolius (yacon), a native plant of South America, was observed to improve lipid profile in rodents and humans. This study aimed to investigate the antiobesity properties of yacon roots in a high-fat-diet (HFD) model and the underlying mechanisms. A total of 30 Wistar male rats were divided into five groups (n=6): the standard chow diet (SD) group was fed a SD; the HFD group was fed a HFD; and the HFD Y340 and HFD Y680 groups were fed a HFD plus yacon flour (340 and 680 mg FOS/kg b. w./day, respectively). HFD Y340 and HFD Y680 rats exhibited marked attenuation of weight gain, a decrease in visceral fat pad weight, a restoration of the serum lipid profile and atherogenic index in a dose-dependent manner, being the higher dose more effective (p < 0.05). In addition, we found that HFD Y680 rats showed lower glucose and insulin levels, improved glucose tolerance, and insulin sensitivity (p < 0.5). A downregulation of several adipocyte specific-transcription factors, including peroxisome proliferator-activated receptor gamma2 (PPAR-γ2), CCAAT/enhancer binding protein a (C/EBP-a) and activating protein (aP2) mRNA levels, was determined in the visceral adipose tissue of HFD Y680 rats (p < 0.05). An improvement of adipokine profile in HFD Y680 rats and decreased serum proinflammatory cytokine levels (p < 0.05) were determined by ELISA. Decreased macrophage infiltration and F4/80 and MCP-1 expression in the visceral adipose tissue of HFD Y680 rats (p < 0.5), together with a higher pAkt/Akt expression (p < 0.05) were also observed by immunofluorescence and immunoblotting. A significant increase in glucagon (Gcg) and PYY mRNA levels in distal ileum of HFD Y680 rats (p < 0.05) were also detected. In the second approach, we determined that yacon supplementation potentiates the effects of the HFD reversion to a standard diet. In conclusion, yacon showed antiobesity properties by inhibiting adipogenesis and improving the visceral adipose tissue function.

Yacon leaf extract supplementation demonstrates neuroprotective effect against memory deficit related to β-amyloid-induced neurotoxicity

Yacon is an Andean plant used as food and medicine; it is rich in phenolic compounds with several activities described. Thus, we investigated the neuroprotective effects of the leaves and roots of yacon in β-amyloid (Aβ)-induced neurotoxicity in rats. Wistar male rats were supplemented with extracts of the leaves or roots of yacon for 14 d before intra-hippocampal injection with 2 μL of Aβ-25–35. The groups were submitted to memory tests and euthanized, and oxidative stress parameters (hippocampus) and biochemical parameters (serum) were analyzed using classical methodologies. Yacon leaf and root extract supplementation decreased oxidative stress and damage in the hippocampus of Alzheimer-like disease (AD-like), but only the leaf extract prevented Aβ-induced memory deficits. The leaf presents more effective neuroprotection than the root and appears to be a likely candidate for future use in the prevention and/or treatment of AD, however further studies are needed to prove this hypothesis.

Дослідження жирнокислотного складу деяких рослин родини айстрові (Аsteraceae)

Introduction. Recently, much attention has been paid to the study of medicinal plants’ lipophilic complexes, part of which is fatty acids, which play an important role in the life activities of a human body. The plants of the Asteraceae family — yacon (the Smallanhus sonchifolius (Poepp. and Endl.) H. Robinson), stevia rebaudiana (Bertoni) Hemsley and cat’s paw (Antennaria dioica (L.) Gaertn.) contain the complex of biologically active substances, among which a significant place is given to lipophilic components (fatty acids, carotenoids, chlorophylls, etc.). In the sources of scientific literature, there is not enough information about the studied species’ fatty acid composition. Therefore, the purpose of our research is to study the lipophilic fractions of stevia leaves, yacon root tubers and leaves, cat’s paw herbs, and to determine the content of fatty acids in their composition.Research Methods. Lipophilic fractions of the studied species are obtained by exhaustive extraction of raw materials with chloroform in the Soxhlet apparatus. Determination of qualitative composition and quantitative content of fatty acids in the investigated medicinal plant material is carried out by the gas-liquid chromatographic/mass spectrometric method of fatty acids methyl esters on the gas chromatographic/mass spectrometric system Agilent 6890N/5973inert (Agilent Technologies, USA). The identification of fatty acid methyl esters in the test mixture is carried out by comparing the retention time of fatty acids methyl esters standard mixture (Supelco, USA). The NIST 02 mass spectrum library is used.Results and Discussion. The isolated lipophilic fraction from yacon root tubers – a thick oily homogeneous mass of brown colour with a pleasant specific odor; not soluble in water and ethanol, is readily soluble in chloroform. Lipophilic fractions of stevia leaves are of dark green colour; cat’s paw herbs – light green colour; according to other physical indicators, the obtained substances do not differ. It is established that the yield of lipophilic substances from yacon and stevia leaves are almost the same – (9.55±0.09)% and (9.05±0.07) %, from yacon roots – in 2.4 and 2.2 times smaller than leaves, respectively. The yield of the lipophilic fraction from cat’s paw herbs is (8.25 ± 0.09) %.9 fatty acids are detected in the lipophilic extract of yacon leaves and cat’s paw herbs, 2 of which are polyunsaturated (linoleic and linolenic). 8 fatty acids are detected in the lipophilic extract of stevia leaves, where linolenic acid is present in the largest number. The lipophilic extract of stevia leaves and cat’s paw herbs contains the saturated palmitic acid. The content of unsaturated fatty acids in the studied lipophilic extracts predominates over saturated. Their ratio in yacon leaves is 55.35:8.63; stevia leaves – 3.04:1.87; cat’s paw herbs – 29.09:20.26, respectively. Only the linoleic and linolenic acids are identified in the lipophilic extract of yacon root tubers.Conclusions. 1. The fatty acid composition of the lipophilic fractions of stevia leaves, yacon root tubers and leaves, and cat’s paw herbs is determined by the gas-liquid chromatographic/mass spectrometric method for the first time.2. The content of unsaturated fatty acids in stevia and yacon leaves, and cat’s paw herbs predominates over saturated. Polyunsaturated fatty acids (linoleic and linolenic) are dominant in the investigated objects.3. Only the linoleic and linolenic acids are identified in yacon root tubers.

Yacon syrup: Food applications and impact on satiety in healthy volunteers

Syrup obtained from yacon roots could be well positioned as a nutritional product due to its high fructooligosaccharides (FOS) content. Considering this, we examined the potential food applications of yacon syrup, using the focal group methodology, and its sensorial acceptability when incorporated in yogurt. The beneficial effects of the consumption of yacon syrup were studied over a 2-week period in a double-blind placebo-controlled experiment (namely Test A) and other consistent of only one day of yacon syrup consumption (namely Test B) were also evaluated. The doses of yacon syrup for both experiments were 8.74g of FOS/day. Energy intake, hunger, satiety, fullness and prospective food consumption were assessed with analogue scales at the end of each test. The results indicate that the yogurt was the food most suggested by the focus group, and the average of the scores given to the attributes when the yacon syrup was incorporated into a yogurt were: 7.78 for appearance; 7.72 for aroma; 7.02 for flavor and 6.96 for overall acceptability, corresponding to “like very much” and “like moderately”. Furthermore, the results indicate that yacon syrup has a positive effect on appetite and its effect was dependent on gender and period of intervention, being statistically significant (P<0.05) in women, after 2-week period. These findings suggested that increasing FOS intake could help to increase satiety, and consequently, be helpful in the management of type 2-diabetes or control of the current high prevalence of overweight or obesity.

Utilização do yacon ( Smallanthus sonchifolius ) na proteção contra colonização intestinal de frangos de corte infectados por Salmonella Enteritidis

RESUMO Os frutanos do tipo inulina são oligossacarídeos que favorecem a multiplicação de determinados gêneros bacterianos no intestino, promovendo um efeito prebiótico. Este trabalho avaliou o efeito da inulina extraída de raízes de yacon (Smallanthus sonchifolius) sobre a colonização intestinal de frangos de corte experimentalmente infectados por Salmonella Enteritidis. Sessenta frangos de corte com um dia de idade foram divididos em três grupos de tratamento, com duas repetições, criados até 21 dias. As aves do grupo yacon receberam 100mg de inulina/dia, via oral, por três dias consecutivos. No sétimo dia de vida, as aves tratadas e o controle positivo foram desafiados pela via oral com uma cultura de S. Enteritidis. Não foram observadas diferenças de desempenho zootécnico entre os grupos. O índice de infectividade das aves suplementadas com yacon foi menor até o sexto dia após o desafio, mas, ao término do experimento, foi superior ao controle positivo. Os dados deste trabalho demonstram que o uso da inulina nos três primeiros dias de vida promoveu uma redução da colonização intestinal dos frangos por Salmonella Enteritidis na primeira semana após o desafio. Novos estudos são necessários para determinar a dose e o tempo de tratamento ideal para um efeito protetor de maior duração.

Sugaring-out-assisted aqueous two-phase extraction of fructooligosaccharides from yacon (Smallanthus sonchifolius)

ABSTRACTYacon roots contain about 80 wt% of β-(2-1)-fructooligosaccharides (FOS). This work aims to use water extraction method combined with sugaring-out technology to extract FOS from yacon. Most of FOS was extracted into the acetonitrile (ACN)-rich top phase, when yacon roots were dissolved in an ACN-yacon water extract mixture without extra sugar addition. Experimental results indicated that the partitioning behavior of FOS was closely correlated with the concentration of sugar in water extract of yacon, the system temperature and the volume ratio between ACN solution and yacon water extract.

Genetic diversity of yacon accessions using ISSR markers.

Yacon cultivation has been intensified and the investigations of this crop have increased at the scientific, agricultural, and social levels because the roots of yacon show beneficial properties for human health, such as reducing cholesterol and glucose blood levels. Since the investigations involving yacon are very recent, there is little information available in terms of the genetic characterization of the cultivated genotypes. In view of the lack of information on the accessions cultivated in the State of Espírito Santo, Brazil, this pioneering study aimed to characterize 60 accessions cultivated in the state using ISSR yacon markers with emphasis on identifying the genetic diversity among the materials. The 20 ISSR primers used produced a total of 82 fragments, 39.6% of which presented polymorphism. The number of fragments per primer ranged from 1 to 10. The dissimilarity values ranged from 0 to 0.54 according to the Jaccard coefficient. A dendrogram was generated in which the accessions were divided into 3 groups; group 1 contained 58 individuals and groups 2 and 3 had only one individual in each group. The clustering of 58 accessions in a single group shows the low diversity in the materials examined. This low diversity indicates that new genotypes must be introduced in order to promote increased variability, which would minimize the adverse effects caused by biotic and abiotic factors.

Characterization of powder from the permeate of yacon extract by ultrafiltration and dehydrated by spray drying

ABSTRACT Yacon root is a functional food which contains antioxidants and prebiotics compounds. This study aimed to evaluate the physical, chemical and prebiotic characteristics of a yacon extract powder obtained by ultrafiltration (UF) with membranes of 10 and 30 kDa and encapsulation of the resulting permeate by spray drying. Drying air temperatures of 140 and 160 ºC and concentrations of gum arabic of 10 and 15% were tested. The samples had solubility values greater than 90% while the hygroscopicity decreased with increasing gum concentration and drying temperature. Electron microscopy showed a strong tendency to agglomeration of smaller particles around the larger ones, mainly at a temperature of 140 ºC. Regarding color, the parameter L* showed that drying at 160 ºC produced darker samples and the parameters a* and b* indicated that all samples were greenish yellow. The concentration of inulin decreased during drying, whereas the levels of glucose and fructose increased due to the thermolysis reaction, which led to degradation of inulin chains at drying temperature. The permeates and retentates from the UF membranes had prebiotic activity, while only the encapsulated product from UF-30 membrane, metabolized by Lactobacillus acidophilus LA-5(r), presented activity scores without significant difference to that of glucose.

Fructan stability in strawberry sorbets in dependence on their source and the period of storage

Many epidemiologic studies have shown a role of diet rich in fruits and vegetables in the prevention of several chronic diseases. Fructans are widely used in functional foods for their health-promoting and technological properties. Strawberry sorbets containing fructans could be an interesting alternative to traditional ice cream. The contents of fructan, glucose, fructose and sucrose were determined to evaluate their changes during storage of strawberry sorbets with three fructan sources: Jerusalem artichoke tubers, yacon root powder and Beneo Orafti Synergy 1. Analyses were performed immediately after product preparation, as well as during 3-month storage at −22 ± 2 °C, in the 2-week intervals. It was observed that the changes of the fructan content were insignificant during the first 2 weeks of storage in all sorbets. The decrease in fructan content was connected with the increase in the amount of glucose, fructose as well as sucrose, independently of fructan source. After 12 weeks of freezing storage, sorbet with Jerusalem artichoke tubers was characterized by the highest stability of fructans, as compared to the other products. The knowledge about the changes of carbohydrate content, especially fructans, during storage is crucial from nutritional point of view (to obtain product with the highest content of pro-healthy compounds).

Polydextrose as Wall Material for Microencapsulation of Yacon Juice by Spray Drying

The juice from yacon roots was encapsulated by spray drying using polydextrose and gum Arabic as wall materials. The effects of the concentration of the encapsulating agents and drying temperature on total phenolics, antioxidant activity, fructooligosaccharides, moisture content, water activity, solubility, hygroscopicity, color, and morphology of the microparticles were investigated to assess the potential use of polydextrose as wall material. The microparticles produced with polydextrose showed retention of bioactive compounds and physicochemical characteristics similar to those produced with gum Arabic. The phenolic retention ranged from 73.67 to 85.49 %, and the antioxidant activity by DPPH varied from 80.78 to 90.58 %. The fructooligosaccharides have undergone little depolymerization into simple sugars even at high temperatures. With respect to the physicochemical characteristics, high stability (low moisture and water activity), low hygroscopicity, and high solubility were observed in the microparticles. The spray dried samples showed a hue angle close to 100, indicating yellow color of the particles. Regarding the microstructure, particle agglomeration was observed in both treatments, probably due to the hygroscopic characteristic of the spray dried powders.

Evaluation of dried yacon (Smallanthus sonchifolius) as an efficient probiotic carrier of Lactobacillus casei LC-01

Recent studies have associated the consumption of yacon root (Smallanthus sonchifolius) with reduced glycemic index. Yacon is rich in fructans and the consumption of its root promotes a prebiotic effect, which can be amplified in the presence of probiotic bacteria. This research studied the viability of Lactobacillus casei (LC-01) in dried yacon that was stored at room temperature. Dried yacon and LC-01 biomass remained in contact for 1 h in temperature 25 °C or 37 °C in the presence or absence of trehalose. The conditions of treatment A (25 °C/without trehalose) proved to be most favorable for the survival of the probiotics, presenting 5.65 log CFU.g−1 after 56 days of storage. The storage time reduced (p < 0.05) the initial amount of probiotics in the sample from 9.35 log CFU.g1 to 7.24 log CFU.g−1 on day 1 and day 56 of storage, respectively. In the case of the sample of treatment A, 84.87% of LC-01 cells survived the simulated stomach conditions and 89.36% survived the simulated intestinal conditions after 56 days.

Yacon (Smallanthus sonchifolius) as a Food Supplement: Health-Promoting Benefits of Fructooligosaccharides

Yacon (Smallanthus sonchifolius), a perennial plant of the family Asteraceae native to the Andean regions of South America, is an abundant source of fructooligosaccharides (FOS). This comprehensive review of the literature addressed the role of yacon supplementation in promoting health and reducing the risk of chronic diseases. According to several preclinical and clinical trials, FOS intake favors the growth of health-promoting bacteria while reducing pathogenic bacteria populations. Moreover, the endproducts of FOS fermentation by the intestinal microbiota, short chain fatty acids (SCFA), act as substrates or signaling molecules in the regulation of the immune response, glucose homeostasis and lipid metabolism. As a result, glycemic levels, body weight and colon cancer risk can be reduced. Based on these findings, most studies reviewed concluded that due to their functional properties, yacon roots may be effectively used as a dietary supplement to prevent and treat chronic diseases.

Mass Transfer Kinetics of the Osmotic Dehydration of Yacon Slices with Polyols

Osmotic dehydration using different polyols was studied. Yacon slices were immersed in solutions of xylitol, maltitol, erythritol, isomalt and sorbitol. The kinetics of solid gain (SG), water loss (WL) and water activity (aw) were evaluated (0, 10, 30, 45, 60, 90 and 120 min). The effective diffusion coefficients of water (Dₑffw) and solids (Dₑffₛ) were calculated with the models of Fick and Barbosa Junior et al. At the end of the process, the highest SG was obtained with erythritol solutions; the lowest with sorbitol and maltitol and intermediate values of SG were acquired in osmotic processes with solutions of isomalt and xylitol. The samples treated in sorbitol, xylitol and erythritol solutions presented the highest Dₑffw and were more effective at increasing WL and reducing aw. The model of Barbosa Junior et al. presented the best fitness. The Dₑffw/Dₑffₛ ratio showed better results for osmotic processes involving sorbitol and xylitol. PRACTICAL APPLICATIONS: Yacon tuber is typical from Latin America. It is considered an important source of fructooligosaccharides (FOS). This class of carbohydrate is employed on the control of diseases such as obesity and diabetes, due its low glycemic index. However, yacon roots are highly perishable and techniques for conservation are required. Osmotic dehydration is a pretreatment process that provides partial water removal from a food product, with low energy consumption. Polyols are widely employed as osmotic agents due their low caloric value. The kinetics of mass transfer on osmotic process are function of process variables, sample matrix characteristics, molecular weight of osmotic agents and others. This study investigate the water loss, solid gain, effective diffusivity and water activity of the OD of yacon with five different polyols and provide information about mass transfer kinetics of osmotic processes using two different empirical models.