Phytochemical Properties and Nutrigenomic Implications of Yacon as a Potential Source of Prebiotic: Current Evidence and Future Directions

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.

Yacon juice as culture and cryoprotectant medium for Latilactobacillus sakei and Staphylococcus vitulinus autochthonous strains

Abstract Yacon is mainly constituted of water and carbohydrates [single sugars and fructooligosaccharides (FOS)], thus being an excellent alternative for the growth and preservation of bacterial culture. Latilactobacillus sakei ACU-2 and Staphylococcus vitulinus ACU-10 comprised the autochthonous starter culture SAS-1 designed for the manufacture of dry sausages. This study evaluated the use of yacon juice as a potential growth medium and cryoprotectant for these bacteria. The growth medium was prepared with yacon juice supplemented with peptone and dipotassium phosphate. After growing, cells were resuspended in yacon juice (5, 10 and 25 mL/100 mL) and lyophilized. Viable cells were count before, immediately after lyophilization, and along 6 months of refrigerated storage. Both bacteria grew in every yacon concentration tested; however, juice concentration affected their growth. Latilactobacillus sakei grew at μ = 0.256 ± 0.01 giving the highest bacterial density at 10 mL/100 mL (Log DOmax 0.33 ± 0.01). While 5 mL/100 mL yacon juice provided the best conditions for S. vitulinus growth (μ = 0.215 ± 0.016; Log DOmax 0.32 ± 0.01). After lyophilization, the survival rate was 91.1% for L. sakei and 65.8% for S. vitulinus. Throughout storage, high cell counts suggested good stability of both bacteria. Results revealed that yacon juice comprises a nutritive substrate for the growth and cryopreservation of tested strains from the genus Latilactobacillus and Staphylococcus.

Protective effects of yacon syrup powder on colonic interleukin-23 and leukocyte infiltration profile in TNBS-induced colitis mouse model

BACKGROUND: Inflammatory Bowel Disease (IBD) causes gastrointestinal tract dysregulation and triggers inflammation. Severe inflammatory events often lead to leukocyte infiltration. Yacon is known to have anti-inflammatory properties, making it a potential alternative treatment for colitis. AIMS: To investigate colonic Interleukin-23 (IL-23) level and leukocyte infiltration profile in 2,4,6-Trinitrobenzene Sulfonic Acid (TNBS)-induced colitis mouse model treated with yacon syrup powder. METHODS: Thirty male BALB/c mice (5 weeks old, body weight: 30.02±1.28 g) were randomly divided into 6 groups (K1-K6). Intra-rectal administration of TNBS was performed to K2-K6 to make the colitis model. K4-K6 were given yacon syrup powder daily for 14 days with the dose of 0.165, 0.331, and 0.662 g/30 g body weight (BW) respectively. IL-23 levels of colonic tissue were measured using ELISA. Leukocyte infiltration profile was calculated through microscopic observation of histology slides and presented in percentage and degree. RESULTS: Significantly different IL-23 levels were observed among the groups (P <  0.001). The percentage and degree of leukocyte infiltration in yacon-treated groups showed a significant decrease compared to colitis groups (P <  0.001). CONCLUSION: Yacon syrup powder provides beneficial effects on colitis mice by lowering the IL-23 level and number of leukocytes at the inflammation site.

Tostes M, Costa NM. The Potential Prebiotic Effects of Yacon (Smallanthus sonchifolius) in Colorectal Cancer

Background:

Colorectal cancer is caused by genetic predisposition and lifestyle risk factors and is associated with altered homeostasis of the intestinal microbiota. Evidence suggests that chronic infection and inflammation contribute to carcinogenic mutagenesis and promote cancer initiation and progression. Food components with prebiotic properties, such as fructooligosaccharides (FOS), promote intestinal integrity and health benefits. Yacon (Smallanthus sonchifolius) is an abundant source of FOS, which are fermented by beneficial bacteria, improving the intestinal environment affected by colorectal cancer.

Objective:

In the current review, the aim was to discuss colorectal cancer and its inflammatory process of development. Also, some general aspects concerning yacon roots and its prebiotic properties are described. Finely, the beneficial effects of yacon to reduce intestinal parameters altered due to colorectal cancer are summarized.

Conclusion:

It was verified that yacon might improve immunological parameters, intestinal barrier, intestinal microbiota, and inflammation in induced colorectal cancer in animals, especially. Researches with humans must be further investigated to prove these positive effects.

A Sustainable Wholesome Foodstuff; Health Effects and Potential Dietotherapy Applications of Yacon

A sustainable food supply is an ever-growing public and planetary health concern influenced by food culture, food practices, and dietary patterns. Globally, the consumption of plant foods that offer physiological and biochemical benefits is increasing. In recent years, products made from yacon (Smallanthus sonchifolius) tubers and leaves, e.g., in the form of syrup, powder, and herbal tea, have steadily emerged with scientific evidence to validate their possible health claims. Yacon was introduced to New Zealand in 1966, and its products can now be produced on a commercial scale. This paper reviews literature published mainly in the last 10 years concerning the health-related properties of yacon as a wholesome foodstuff and its bioactive components, e.g., fructooligosaccharides. Literature was sourced from Web of Science, PubMed, EBSCO Health, and Google Scholar up to June 2019. The potential markets for yacon in the field of food technology and new dietotherapy applications are discussed. Furthermore, the unique features of New Zealand-produced yacon syrup are introduced as a case study. The paper explores the scientific foundation in response to the growing public interest in why and how to use yacon.

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/.

Goji Berries as a Potential Natural Antioxidant Medicine: An Insight into Their Molecular Mechanisms of Action

Goji berries (Lycium fruits) are usually found in Asia, particularly in northwest regions of China. Traditionally, dried goji berries are cooked before they are consumed. They are commonly used in Chinese soups and as herbal tea. Moreover, goji berries are used for the production of tincture, wine, and juice. Goji berries are high antioxidant potential fruits which alleviate oxidative stress to confer many health protective benefits such as preventing free radicals from damaging DNA, lipids, and proteins. Therefore, the aim of the review was to focus on the bioactive compounds and pharmacological properties of goji berries including their molecular mechanisms of action. The health benefits of goji berries include enhancing hemopoiesis, antiradiation, antiaging, anticancer, improvement of immunity, and antioxidation. There is a better protection through synergistic and additive effects in fruits and herbal products from a complex mixture of phytochemicals when compared to one single phytochemical.

Effects of Tempeh Fermentation with Lactobacillus plantarum and Rhizopus oligosporus on Streptozotocin-Induced Type II Diabetes Mellitus in Rats

The increased consumption of high fat-containing foods has been linked to the prevalence of obesity and abnormal metabolic syndromes. Rhizopus oligosporus, a fungus in the family Mucoraceae, is widely used as a starter for homemade tempeh. Although R. oligosporus can prevent the growth of other microorganisms, it grows well with lactic acid bacteria (LAB). Lactobacillus plantarum can produce β-glucosidase, which catalyzes the hydrolysis of glucoside isoflavones into aglycones (with greater bioavailability). Therefore, the development of a soybean-based functional food by the co-inoculation of R. oligosporus and L. plantarum is a promising approach to increase the bioactivity of tempeh. In this study, the ameliorative effect of L. plantarum in soy tempeh on abnormal carbohydrate metabolism in high-fat diet (HFD)-induced hyperglycemic rats was evaluated. The co-incubation of L. plantarum with R. oligosporus during soy tempeh fermentation reduced the homeostatic model assessment of insulin resistance, HbA1c, serum glucose, total cholesterol, triglyceride, free fatty acid, insulin, and low-density lipoprotein contents, and significantly increased the high-density lipoprotein content in HFD rats. It also increased the LAB counts, as well as the bile acid, cholesterol, triglyceride, and short-chain fatty acid contents in the feces of HFD rats. Our results suggested that the modulation of serum glucose and lipid levels by LAB occurs via alterations in the internal microbiota, leading to the inhibition of cholesterol synthesis and promotion of lipolysis. Tempeh, which was produced with both L. plantarum and R. oligosporus, might be a beneficial dietary supplement for individuals with abnormal carbohydrate metabolism.

Phytochemical Profile of Brown Rice and Its Nutrigenomic Implications

Whole grain foods have been promoted to be included as one of the important components of a healthy diet because of the relationship between the regular consumption of whole-grain foods and reduced risk of chronic diseases. Rice is a staple food, which has been widely consumed for centuries by many Asian countries. Studies have suggested that brown rice is associated with a wide spectrum of nutrigenomic implications such as anti-diabetic, anti-cholesterol, cardioprotective and antioxidant. This is because of the presence of various phytochemicals that are mainly located in bran layers of brown rice. Therefore, this paper is a review of publications that focuses on the bioactive compounds and nutrigenomic implications of brown rice. Although current evidence supports the fact that the consumption of brown rice is beneficial for health, these studies are heterogeneous in terms of their brown rice samples used and population groups, which cause the evaluation to be difficult. Future clinical studies should focus on the screening of individual bioactive compounds in brown rice with reference to their nutrigenomic implications.

Effects of Mulberry Fruit (Morus alba L.) Consumption on Health Outcomes: A Mini-Review

Mulberry (Morus alba L.) belongs to the Moraceae family and is widely planted in Asia. Mulberry fruits are generally consumed as fresh fruits, jams and juices. They contain considerable amounts of biologically active ingredients that might be associated with some potential pharmacological activities that are beneficial for health. Therefore, they have been traditionally used in traditional medicine. Studies have reported that the presence of bioactive components in mulberry fruits, including alkaloids and flavonoid, are associated with bioactivities such as antioxidant. One of the most important compounds in mulberry fruits is anthocyanins which are water-soluble bioactive ingredients of the polyphenol class. Studies have shown that mulberry fruits possess several potential pharmacological health benefits including anti-cholesterol, anti-obesity and hepatoprotective effects which might be associated with the presence of some of these bioactive compounds. However, human intervention studies on the pharmacological activities of mulberry fruits are limited. Therefore, future studies should explore the effect of mulberry fruit consumption on human health and elucidate the detailed compounds. This paper provides an overview of the pharmacological activities of mulberry fruits.