Family • Asteraceae - Smallanthus sonchifolius - POTATO BEAN

Scientific names

Smallanthus sonchifolius (Poe.& Endl.) H. Robinson
Polymnia edulis Wedd.
Polymnia sonchifolia Poepp. & Endl.

Common names

Yacon (Tag.)
Earth apple (Engl.)
Peruvian ground apple (Engl._
Potato bean (Engl.)
Yacon strawberry (Eng.)

Other vernacular names

AMARA: Aricona, Aricoma (Bolivia), Aricuma (Bolivia).
FRENCH: Poire de terre.
QUECHUA: Llacjon, Llacoma, Llacón (Peru, Bolivia), Llacum, Llacuma, Llakuma (Peru, Bolivia), Llamón, Llaqon, Yacumpi.
SPANISH: Arboloco (Colombia), Chicama, Colla, Jacón, Jícama, Jíquima (Venezuela, Colombia, Ecuador), Jíkima, Jiquimilla (Venezuela, Colombia), Polaco, Puhe, Racón, Shicama, Taraca, Yacón (Bolivia, Peru).

General info 
A member of the sunflower family, native to the lower Peruvian Andes and many many South American forest regions, and long valued as a root crop. It was first recorded as a native cultivated root crop by the Andeans in 1615. Fresh tubers are crisp and juicy redolent of apples and melons, sometimes referred to as “Apple of the Earth.” It has a sweetness that increases with storage. Eaten raw, baked, roasted, jammed, juiced into syrup or drinks, or made into pudding dishes.


Yacon is a perennial herb growing to a height of 2 to 3 meters. Leaves are broadly ovate with widely toothed margins and extending into the stems. Flowers are daisy-like, yellow to orange, avidly pollinated by insects. Root crop is edible, fleshy, yellowish white, sweet, with a crisp consistency of sinkamas.


– Recently introduced and cultivated in the Mountain Province area.
– Originally cultivated in the Andean highlights.
– Reported in China and Japan.


• The root or tuber is a rich source of fructo-oligosaccharides (FOS), ‘prebiotics’ responsible for the sweet flavor while poorly metabolized or digested, a characteristic for a potential low calorie sweetener.
• Probiotic and antioxidant properties from protocatechuic, chlorogenic, caffeic and ferulic acids found in the leaves.
• Inulin may be responsible for its effect on blood sugar.
• Leaves yield monoterpenes, sesquiterpenes, and diterpenes.
• Tubers yield a high content of oligofructans and polyphenols.
• Other chemicals documented in yacon include: y-cadinene, caffeic-acid, 3-caffeoylquinic-acid, chlorogenic-acid, 2,4-dicaffeoylaltraric-acid, 2,5-dicaffeoylaltraric-acid, 3,5-dicaffeoylaltraric-acid, 3,5-dicaffeoylquinic-acid, enhydrin, ferulic-acid, fluctuanin, gallic-acid, gentisic-acid, inulin, melampolides, oligofructans, beta-pinene, protocatechuic-acid, rosmarinic-acid, sonchifolin, tryptophan, 2,3,5-tricaffeoylaltraric-acid, 2,4,5-tricaffeoylaltraric-acid, and uvedalin.
• Chloroform fraction of alcohol extract of leaves yielded seven compounds: gallic acid, beta-sitosterol, behenic acid, Kaempferol, Quercetin, vanillic acid, hexadecanoic acid
• Major portion of tuberous root biomass is water (>70% of fresh weight), saccharides, especially oligofructans (70-80% of dry weight), protein content (0.3% to 3.7%).
• Mean tuberous root composition per 100 g of fresh matter is: water 81.3, saccharides 13.8, fiber 0.9, proteins 1.0, lipids 0.1, and ash 1.1.
• Mean mineral content per 100 g of fresh matter are: potassium 334, phosphorus 34, calcium 12, magnesium 8.4, sodium 0.4 and iron 0.2. Vitamins B1, B2, C, β-carotene and polyphenols in the same weight are present at mean concentrations 0.07, 0.31, 5.0, 0.13 and 203 mg, respectively.
• Leaves yield di- and sesquiterpenes, polyphenolic antioxidants, esp. hydroxycinnamic acids and chlorogenic acid; a new antifungal melampolide – sesquiterpene lactone named sonchifolin, as well as three known melampolides, polymatin B, uvedalin and enhydrin.

• Hypoglycemic, antioxidant, antibacterial, antifungal, liver protector.
• Antibacterial, antifungal, antidiabetic.

Additional Sources and Suggested Readings

(1) Local Root Crops as Antioxidant

(2) Yacon / Tropical Plant Database / Raintree

(3) Yacon / Wikipedia

(4) Investigation of phenolic acids in yacon (Smallanthus sonchifolius) leaves and tubers / Breda Simonnovska et al / Journal of Chromatography A • Volume 1016, Issue 1, 17 October 2003, Pages 89-98 / doi:10.1016/S0021-9673(03)01183-X /

(5) Smallanthus sonchifolius and Lepidium meyenii – prospective Andean crops for the prevention of chronic diseases / Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2003 Dec;147(2):119-30.

(6) Subchronic 4-month oral toxicity study of dried Smallanthus sonchifolius (yacon) roots as a diet supplement in rats / Susana B Genta et al / Food and Chemical Toxicology
Volume 43, Issue 11, November 2005, Pages 1657-1665 / doi:10.1016/j.fct.2005.05.00

(7) Antibacterial and synergistic effects of Smallanthus sonchifolius leaf extracts against methicillin-resistant Staphylococcus aureus under light intensity / Hee Joung et al / Journal of Natural Medicines • 10.1007/s11418-010-0388-7

(8) Study on chemical constituents of Smallanthus sonchifolius / Xie W, Li J, Li HM. / Zhong Yao Cai. 2008 Oct;31(10):1510-2.

(9) Anti-diabetes constituents in leaves of Smallanthus sonchifolius / Xiang Z, He F, Kang TG, Dou DQ, Gai K, Shi YY, Kim YH, Dong F. / Nat Prod Commun. 2010 Jan;5(1):95-8

(10) Sorting Smallanthus names / /Maintained by: Michel H. Porcher / MULTILINGUAL MULTISCRIPT PLANT NAME DATABASE / Copyright © 1995 – 2020 / A Work in Progress. School of Agriculture and Food Systems. Faculty of Land & Food Resources. The University of Melbourne. Australia.

(11) Yacon diet (Smallanthus sonchifolius, Asteraceae) improves hepatic insulin resistance via reducing Trb3 expression in Zucker fa/fa rats / H Satoh, M T Audrey Nguyen, A Kudoh  and T Watanabe / Nutrition & Diabetes (2013) 3, e70; doi:10.1038/nutd.2013.11

(12) Study of the effect exerted by fructo-oligosaccharides from yacon (Smallanthus sonchifolius) root flour in an intestinal infection model with Salmonella typhimurium / Natalia Alejandra Castillo et al / The British journal of nutrition (Impact Factor: 3.45). 11/2012; DOI: 10.1017/S0007114512004230

(13) Antimicrobial activity of the constituents of Smallanthus sonchifolius leaves against methicillin-resistant Staphylococcus aureus / J.G. CHOI, O.H. KANG, Y.S. LEE, Y.C. OH, H.S. CHAE, B. OBIANG-OBOUNOU,
S.C. PARK, D.W. SHIN*, B.Y. HWANG**, D.Y. KWON / European Review for Medical and Pharmacological Sciences, 2010; 14: 1005-1009

(14) Trypanocidal Activity of Smallanthus sonchifolius: Identification of Active Sesquiterpene Lactones by Bioassay-Guided Fractionation / F M Frank, J Ulloa, S I Cazorla, G Maravilla et al / Evidence-Based Complementary and Alternative Medicine, Volume 2013 (2013) / http://dx.doi.org/10.1155/2013/627898

(15) Smallanthus sonchifolius and Lepidium meyenii – prospective Andean crops for the prevention of chronic diseases. / Valentová K1, Ulrichová J. / Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2003 Dec;147(2):119-30.

(16) Effect of crude extracts of leaves of Smallanthus sonchifolius (yacon) on glycemia in diabetic rats / Silmara Baroni, Fumie Suzuki-Kemmelmeier, Silvana Martins Caparroz-Assef, Roberto Kenji Nakamura Cuman, Ciomar Aparecida Bersani-Amado / Revista Brasileira de Ciências Farmacêuticas / Brazilian Journal of Pharmaceutical Sciences, vol. 44, n. 3, jul./set., 2008

(17) Renal toxicity caused by oral use of medicinal plants: The yacon example / Rejane Barbosa de Oliveira, Daniela Aparecida Chagas de Paula, Bruno Alves Rocha, João José Franco, Leonardo Gobbo-Neto, Sérgio Akira Uyemura, Wagner Ferreira dos Santos, Fernando Batista Da Costa / Journal of Ethnopharmacology
133 (2011) 434–441

(18) The effect of Smallanthus sonchifolius leaf extracts on rat hepatic metabolism / K. Valentová, A. Moncion, I. de Waziers, J. Ulrichová / Cell Biology and Toxicology, March 2004, Volume 20, Issue 2, pp 109-120

(19) Prebiotic effect of yacon (Smallanthus sonchifolius) on intestinal mucosa using a mouse model / M. E. Bibas Bonet, O. Meson, A. de Moreno de LeBlanc, C. A. Dogi, S. Chaves, A. Kortsarz, A. Grau, G. Perdigón / FOOD AGRIC IMMUNOL , vol. 21, no. 2, pp. 175-189, 2010 / DOI: 10.1080/09540100903563589

(20) Protective effects of yacon (Smallanthus sonchifolius) intake on experimental colon carcinogenesis / Nelci A. de Moura, Brunno F.R. Caetano, Kátia Sivieri, Luis H. Urbano, Claudio Cabello, Maria A.M. Rodrigues, Luis F. Barbisan / Food and Chemical Toxicology 50 (2012) 2902–2910

(21) Effect of Smallanthus sonchifolius extracts on croton oil-induced oedema and neutrophil migration to the ear skin tissue of mice / R Oliveira, D Chagas-Paula, T Gasparato, L Faccioli, F Da Costa / Planta Med 2010; 76 – P363 / DOI: 10.1055/s-0030-1264661

Yacon4Parts utilized 
Leaves and tubers.

– Fresh tubers are crisp and juicy when eaten raw; sweetness increases with storage.
– Tubers also steamed, baked, or roasted. Also, processed into jams, juice, cereals, etc.
– In Japan and Brazil, aerial parts used as components of medicinal tea.

-Decoction of leaves used as tea for diabetics.
– In South America, the raw tubers as a diuretic for kidney and bladder problems.
– In Bolivia, leaves are decocted for cystitis, hepatosis and nephrosis.
– In Peru, warm poultice of leaves used for myalgias and rheumatism.
– In Brazil, leaves decocted for diabetes.

Yacon5Study Findings
• Local Root Crops as Antioxidant: A 2006 study of commonly consumed roots crops in the Philippines (Kamote, Ipomoea batata; ubi, purple yam, Dioscorea alata; cassava, Manihot esculenta; taro or gabi, Colocasia esculenta; carrot, Daucus carota; yacon (Smallanthus sonchifolius) showed them to be rich sources of phenolic compounds with antioxidant activity, highest in sweet potato, followed by taro, potato, purple yam and lowest in the carrot.
• Phenolic Acid / Antioxidant: A study of the crude extracts of dried leaves and tubers of yacon yielded phenolic acids – chlorogenic, caffeic and ferulic acids – contributing to the radical scavenging activity detected.
• Cytoprotective / Anti-hyperglycemic: Report suggests the anti-hyperglycemic activity of tubers and cytoprotective activity of its leaves are probably due to the oligofructan and phenolic content, respectively.
• Prebiotic: Inulin and oligofructose from the extracts of yacon roots known for its prebiotic properties presents a potential use in treating certain types of colitis by stimulating growth of Lactobacillus and Bifidogacterium microflora.
• Constipation / Colonic Transit Time: Yacon syrup’s effect on colon-transit time was studied in healthy volunteers. Results showed an softer stools and acceleration of colonic transit time. With its low caloric content, it presents a potential for the treatment of constipation in the obese and diabetic.
• Subchronic Toxicity Studies: A 4-month oral consumption of dried yacon root flour and diet supplement on normal Wistar rats showed to be well tolerated with no negative responses, toxicity, or adverse nutritional effects. It showed significantly reduced serum triglyceride levels.
• Antioxidant / Cytoprotective/ Antihyperglycemic: All extracts exhibited strong protective activity against oxidative damage to rat hepatocyte cultures, reduced hepatic glucose production via gluconeogenesis and glycogenolysis. The combination of radical scavenging, cytoprotective and antihyperglycemic activities presents a potential use in the prevention and treatment of chronic diseases involving oxidative stress, especially diabetes.
• Antibacterial: Study showed the enhancement and antimicrobial activity of yacon leaves against methicillin-resistant Staphylococcus aureus in the presence of light.
• Antiteratogenic Potential: Extracts from the leaf of P. laevigata and yacon tubers (Smallanthus sonchifolius) were studied for antiteratogenic potential using duck embryos. Extracts administered with retinoic acid had antiteratogenic properties.
• Antidiabetic / Alpha-Glucosidase Inhibition: Study evaluated the inhibitory effect of smallanthaditerpenic acids A, B, C and D on alpha-glucosidases. Their IC50 were determined to be 0.48 mg/mL, 0.59 mg/mL, 1.00 mg/mL, and 1.17 mg/mL respectively.
• Antidiabetic / Tubers: Study evaluated the hypoglycemic effect of yacon tubers on alloxan-induced diabetes in mice. Results showed yacon significantly reduced blood sugar level.
• Decreased Hepatic Insulin Resistance: Study evaluated the effect of a yacon diet on blood glucose. Results showed reduction of blood glucose likely due to its beneficial effects on hepatic insulin sensitivity in the insulin resistance state.
• Yacon FOS (Fructo-Oligosaccharides) / Prebiotic: Study have shown the benefits of prebiotics like inulin and FOS in health and nutrition. This study showed yacon can prevent enteric infection caused by S. typhimurium, the effect mediated by enhancing non-specific immunity, such as total S-IgA, that improves the immunological intestinal barrier.
• Antibacterial Activity of Leaf Constituents / Enhydrin: Study investigated the antibacterial activity of leaf constituents enhydrin, polymatin B, alloschkuhriolide. Results showed only enhydrin showed antibacterial activity against MRSA (methicillin resistant Staphylococcus aureus).
• Yacon Fructans Effect on Maintenance of Healthy Bones: Yacon flour consumption significantly resulted in a positive Ca and Mg balance leading to higher bone mineral retention and biomechanical properties. The positive effects on mineral intestinal absorption, bone mass, and biomechanical properties showed yacon’s important role in the maintenance of healthy bones.
• Trypanocidal / Chagas Disease: Study isolated sesquiterpene lactones enhydrin, uvedalin, and polymatin B from an organic extract of S. sonchifolius. The compounds were tested for trypanocidal activity against Trypanosoma cruzi. Results suggest enhydrin and uvedalin might have potential as agents against Chagas disease.
• Antioxidant / Leaves: Study evaluated various extracts of leaves for antioxidant activity and phenolic content. Study yielded protocatechuic, chlorogenic, caffeic and ferulic acids from two fractions. Both fractions showed potent antioxidant activity in the DPPH and xanthine/XOD superoxide radical scavenging tests. Results suggest the use of leaves in human diet may be a potential remedy for the prevention of chronic diseases cause by radicals, e.g., arteriosclerosis.
• Constituents and Activities: Study evaluated the botany, composition, and main constituents of Smallanthus sonchifolius (yacon) and Lepidium meyeni (maca). The potential of yacon tubers to treat hyperglycemia, kidney problems and skin rejuvenation and the antihyperglycemic and cytoprotective activity of leaves seem mostly related to its oligofructan and phenolic content.
• Glycemic Effect in Diabetic Rats: Study of crude extracts of leaves showed on STZ induced glycemia in rats showed the effectiveness of yacon extracts is related to the method of preparation and time of treatment. The hydroalcoholic extract significantly reduced the levels of glucose in the diabetic rats.
• Caution / Renal Toxicity Report / Leaves: Study evaluated the repeated-dose toxicity of three extracts of yacon leaves. Results showed renal damage associated with increased blood glucose levels after prolonged oral administration of aqueous extract. Evidence suggests the terpenoids were the main toxic compounds. Based on the results, the oral use of yacon leaves is not recommended to treat diabetes.
• Effect of Hepatic Metabolism: Study of extracts and fractions of leaves extracts showed strong protective effect against oxidative damage to rat hepatocyte cultures, reduced glucose production via gluconeogenesis and glycogenolysis. The combination of radical scavenging, cytoprotective and anti-hyperglycemic activity of leaves suggest potential for use in prevention and treatment of chronic diseases involving oxidative stress, particularly diabetes.
• Prebiotic Effect on Intestinal Mucosa / Yacon Root Flour: Study evaluated the prebiotic property of yacon root flour and its influence on the intestinal microbiota and gut immune system using a mice model. Results showed long term administration of yacon root flour maintained the intestinal homeostasis without inflammatory effect regulated through IL-10 and IL-4 regulatory cytokines.
• Protective Effect / Colon Carcinogenesis: Study investigated the potential benefit of yacon intake on colon carcinogenesis induced by DMH in male Wistar rats. Results showed a significant reduction in number of aberrant crypt foci and number of invasive adenocarcinomas. Yacon root intake may have a potential s chemopreventive agent against colon carcinogenesis.
• Topical Anti-Inflammatory / Effect on Neutrophil Migration: Study evaluated the in vivo topical anti-inflammatory potential of a leaf-rinse extract from dried leaves of yacon on croton oil ear edema assay in mice. Results showed topical anti-inflammatory effect with anti-oedematogenic activity followed by inhibition of neutrophil migration.

Although the roots and tubers are popular marketed for its diabetic benefits, many studies report the hypoglycemic or sugar-lowering effect only in the leaves.

Commercial herbal tea leaves.
Root and leaf extracts in the cybermarket.