Available online: www.notulaebotanicae.ro Print ISSN 0255-965X; Electronic 1842-4309 Notulae Botanicae Horti AcademicPres Not Bot Horti Agrobo, 2019, 47(3):813-820. DOI:10.15835/nbha47311552 Agrobotanici Cluj-Napoca Original Article Physicochemical Quality, Antioxidant Capacity and Nutritional Value in Tuberous Roots of Some Wild Dahlia Species Esteban A. RIVERA-ESPEJEL 1, Oscar CRUZ-ALVAREZ 2, José M. MEJÍA- MUÑOZ 1, María R. GARCÍA-MATEOS 1, María T.B. COLINAS-LEÓN 1, María Teresa MARTÍNEZ-DAMIÁN 1* 1Autonomous University Chapingo, Department of Plant Science, Km. 38.5 Mexico-Texcoco Highway, CP 56230 Chapingo, State of Mexico, Mexico; [email protected]; [email protected] ; [email protected] ; [email protected] ; [email protected] (*corresponding author) 2Autonomous University of Chihuahua, Faculty of Agrotechnological Sciences, Pascual Orozco Avenue, Campus 1, Santo Niño, CP 31350 Chihuahua, Mexico; [email protected] Abstract The aim of this research was to evaluate the physicochemical quality, antioxidant capacity and nutritional value in tuberous roots of some wild dahlia species. The experiment was carried out in the Department of Plant Science of the Autonomous University Chapingo, Mexico. Plants were established in a randomized complete block design with five replications. The total soluble solids (TSS), titratable acidity (TA), vitamin C (VC), total phenols (TP), antioxidant capacity (AC), inulin and its proximate composition were evaluated. Among the materials analyzed, the most outstanding wild species were Dahlia campanulata , D. coccinea and D. brevis , where D. campanulata stood out for its concentration of VC (0.05 mg 100 g -1), AC (1.88 mg VCEAC g -1), inulin, DM and TC (72.25, 24.38 and 88.37%, respectively), however, the inulin content was similar to D. coccinea (66.17%), which was also outstanding with respect to the content of TP (1.74 mg GA g-1). Likewise, D. brevis presented the highest values of RFi (5.49%) and A (78.42%). According to our results, the tuberous roots of wild dahlia species can be used as food, as well as being a source of selection of traits of nutraceutic interest for genetic improvement. Keywords: Dahlia sp.; edible tuber; fiber crude; nutraceutical and functional food; inulin content Abbreviations: TSS: total soluble solids; TA: titratable acidity; VC: Vitamin C; TP: total phenols; AC: antioxidant capacity; M: Moisture; DM: Dry matter; RP: Raw protein; RF: Raw fat; RFi: Raw fiber; TC: total carbohydrate; A: Ashes; HSMD: honest significant minimum difference ; GA: gallic acid; VCEAC: Vitamin C equivalent antioxidant capacity At present, the general consumption of food products with high caloric value and poor nutritional contribution, has increased the incidence of cardiovascular, Introduction neurodegenerative, chronic diseases and some cancer types (Das et al ., 2012; Lara et al ., 2014; Ciobanu et al ., 2016), The Dahlia genus (Asteraceae) is composed of 37 however, a “boom” has also been generated in the search and analysis of natural foods with outstanding characteristics, species and Mexico is the center of origin and domest ication of most of them (Castro et al ., 2015), and among the from the nutritional point of view and health care (bioactive ornamental plants (cut flower, pot and as a structural compounds) (Shahidi and Zhong, 2010; Doporto et al ., element in the design and construction of gardens), are the 2011; Rodríguez et al ., 2017; Frias et al ., 2019), and an most widely distributed worldwide with approximately alternative source of these compounds is found in wild 20,000 varieties (Arenas et al ., 2011, Jiménez, 2015), plants (Pinela et al ., 2017). Fossil remains indicate the however, studies indicate that in the prehispanic era the nutritional and medicinal use of diverse vegetal organs of tuberous roots of this plant were consumed as a source of wild plants (Vandoorne et al ., 2012), and in the particular carbohydrates, that is, as an equivalent of potatoes ( Solanum case of the roots and underground storage organs, are no tuberosum L.) (Santana et al ., 2016). exception, being rich in polysaccharides and others Received: 06 May 2019. Received in revised form: 28 May 2019. Accepted: 29 May 2019. Published online: 31 May 2019. Rivera-Espejel EA et al / Not Bot Horti Agrobo, 2019, 47(3):813-820 814 compounds (minerals, vitamins, phenolic compounds, some crop management practices such as hilling were proteins, fiber, among others) with a possible antioxidant carried out manually. At the time the plants stopped their effect (Zaldariene et al ., 2012; Chandrasekara and Kumar, growth and defoliation appeared (December), it is preceded 2016). with the harvest of the tuberous roots. Among the important components of the tuberous roots of the dahlia is inulin (Arenas et al ., 2011; Ciobanu et Experimental design al ., 2016), a storage carbohydrate that has a wide nutritional They were established with an experimental design of and pharmaceutical importance (Melanie et al ., 2015) , due randomized complete block with five replications where the experimental unit consisted of 14 plants (7.2 m 2). For to its prebiotic activity, and constitutes an effective support treatment for acute and chronic intestinal disorders laboratory analyzes, 500 g of tuberous roots of each species (Nsabimana and Jiang, 2011), also improves the were taken as an experimental unit with five replications, bioavailability of calcium and magnesium, with promising where the content of total soluble solids, vitamin C, evidence in the reduction of cancer risk, reinforcement of titratable acidity, antioxidant capacity, inulin content, as well as the p roximal composition were evaluated (moisture, the immune response and protection against intestinal disorders, has a low caloric value, decreases the risk of high dry matter, crude protein, crude fat, crude fiber, total concentrations of triglycerides, in addition to favoring the carbohydrates and ashes). development of beneficial bacteria in the colon (Santana et al ., 2016; Başaran et al ., 2017). It is for all the above, that the Parameters evaluated objective of the present investigation was to evaluate the Total soluble solids (TSS) physico chemical quality, antioxidant capacity and The measurement of TSS was performed according to the methodology of the AOAC (2000). A PAL-1 manual nutritional value in tuberous roots of some wild dahlia ® species ( Dahlia spp.). digital refractometer (ATAGO , Japan) was used, for which a drop of a tuberous root portion was extracted through a 2 polypropylene mesh of 17 threads per inch to avoid the Materials and Methods passage of solid material, which it was deposited in the pris m of the refractometer sampling area and the reading was Plant material and location of the experiment obtained, then the sampling area was washed with distilled In this experiment, tuberous dahlia roots were used that water and the next measurement was carried out. The were obtained from the species ( Dahlia brevis, D. merckii, results were expressed in °Brix. D. coccinea and D. campanulata ) (wild) and cultivated ( D. x hortorum ), which were cultivated during the April - Titrable acidity (TA) December 2016 in the Experimental Agricultural Field Its determination was made acco rding to the “San Martin” of the Autonomous University Chapingo , methodology of the AOAC (2000), for which 2 g of sample Mexico (19° 29´ 23”, 98° 53´ 37” W and at 2 246 meters were weighed and homogenized with 10 mL of distilled water, later it was filtered with a polypropylene mesh and above sea level (masl)) with average annual temperature and precipi tation of 18.9 °C and 619.3 mm, respectively. The the final volume was determined, then a 5 mL aliquot was analyzes of the plant material were carried out during the taken and a 1% phe nolphthalein drop was added as months of January-June 2017 in the Laboratory of Multiple indicator, neutralized with 0.1 N sodium hydroxide Uses and Physiology of Fruit Trees of the Department of (NAOH). The results are expressed as a percentage of citric acid. Plant Science of the Autonomous U niversity Chapingo. On the other hand, among the most outstanding physical and chemical characteristics of the soil are: pH (7.48), electrical Vitamin C (VC) conductivity (0.73 dS m -1), cation exchange capacity (24.4 It was carried out by the method described by Jagota and -1 -3 cmol kg ), bulk density (1.29 g cm ) and clay-loam texture. Dani (1982), with slight modificat ions. To 0.3 g of sample was added 5 mL of 10% trichloroacetic acid, then Crop management homogenized and agitated vigorously for 5 min in cold (ice), To multiply and obtain the plant material, it started in proceeded to centrifuge for 20 min at 20 000 rpm at 5 °C. March 2016 with the greenhouse planting of the tuberous Subsequently, an aliquot of 200 μL of the supernatant of roots obtained from the previous cycle in boxes with peat each sample was taken, and 1.8 mL of bidistilled water and (peat moss), whose buds emerged after 15 days. The field 200 μL of the 10% Folin-Ciocalteu reagent (v:v) were tr ansplant was carried out in the month of April 2016, added. The mixture was vigorously stirred for 15 seconds where the distance between plants and rows was 0.6 and 1 and allowed to stand for 10 min, to subsequently perform m, respectively. The supply of water and nutrients, was the absorbance reading at 760 nm using the Genesys 10-STM carried out by a drip irrigation system of 1-2 times per week spectrophotometer (Thermo scientific, USA). The -1 -1 with an expense of 0.5 -3.5 L plant , depending on the concentration was expressed in mg 100 g , by calibrating a climatic conditions (environmental temperature and standard curve of ascorbic acid. relative humidity) and phenological stages of the crop. The fertilization was carried out based on a previous analysis of Total phenols (TP) soil fertility and the general formula of fertilization 120-0- The determination of total phenols was car ried out 200, which was split into two applications (the transplant using the Folin-Ciocalteu method described by Waterman and before the beginning of flowering).