Physicochemical, functional and antinutritional properties of starches from Caladium bicolor and Dioscorea dumentorum European Journal of Chemistry 10 (3) (2019) 228-233 European Journal of Chemistry View Journal Online View Article Online Physicochemical, functional and antinutritional properties of starches from Caladium bicolor and Dioscorea dumentorum Ifiok Nseobong Uwem and Basil Nse Ita * Department of Chemistry, Faculty of Sciences, University of Uyo, Uyo, P.M.B. 1017, Nigeria basil_ita@yahoo.com (B.N.I.), ifioknuwem@gmail.com (I.N.U.) * Corresponding author at: Department of Chemistry, Faculty of Sciences, University of Uyo, Uyo, P.M.B. 1017, Nigeria. Tel: +234.80.23348014 Fax: +234.80.23348014 e-mail: basil_ita@yahoo.com (B.N. Ita). 10.5155/eurjchem.10.3.228-233.1833 Received: 19 February 2019 Received in revised form: 20 May 2019 Accepted: 30 May 2019 Published online: 30 September 2019 Printed: 30 September 2019 Starch samples from the wild species of cocoyam (Caladium bicolor (Aiton) Vent.) and three leaf yam (Dioscorea dumentorum (Kunth) Pax.) found abundantly in the south and eastern regions of Nigeria, were characterized for their physicochemical, functional and antinutrient properties. C. bicolor had higher amylose (17.68%), carbohydrate (83.57%) and ash (2.85%) than D. dumentorum. Moisture, crude lipid, protein and fibre ranged between 7.56 to 10.29%, 0.12 to 0.15%, 0.11 to 0.13%, and 2.85 to 3.39%, respectively. The starches exhibited promising functional properties with D. dumentorum having higher dispersibility (64.85%), solubility (73.99%) and oil absorption capacity (2.15 g/g). Onset (To), midpoint (Tm), and conclusion (Tc) gelatinization temperatures ranged between 63 to 79 °C. Peak, breakdown and setback viscosity were higher in D. dumentorum than C. bicolor. Moisture sorption behavior indicated increased hygroscopy with exposure time. The starches had high antinutrient levels, with D. dumentorum having higher levels of HCN and oxalates. In addition, infrared (IR) spectra of both starches were similar. Taken together, these properties suggest the suitability of these starches for non-food applications due to their high antinutrient contents. Starch Caladium bicolor Functional property Antinutrient content Dioscorea dumentorum Physico-chemical property Cite this: Eur. J. Chem. 2019, 10(3), 228-233 Journal website: www.eurjchem.com 1. Introduction Starch is the most abundant carbohydrate found naturally. Produced and stored in tissues of green plants, it is also the most common carbohydrate in human diet. Starchy tubers, root crops and cereals are important food sources in Nigeria and other parts of the world [1]. Starch finds wide application in the food and non-food industries because of their varying physicochemical and functional properties. Numerous studies exist on starches from cereals such as maize, wheat, millet, rice and root crops such as cassava, potato, yam, etc. for food and industrial purposes [2-9]. In Nigeria, these cereals and root crops are staple foods; this places huge constraints on the utilization of their starches for industrial purposes, hence the need to explore the properties of other starch- rich biomass becomes imperative. Wild C. bicolor (family Araceae) and wild D. dumentorum (family Dioscoreaceae) are two underutilized, inedible root tubers found abundantly in the wild in the south and south east regions of Nigeria. C. bicolor is used as an ornamental plant in some areas, the leaves and rhizomes are used medicinally as topical application for boils, wounds and ulcers. It is used as purgatives and in the treatment of convulsion [10]. The potential of its flour for bio-ethanol production using indigenous fungal isolates has been reported [11]. Wild D. dumentorum is not eaten in Nigeria, but is cultivated and consumed in Ghana, Cameroun and other West African countries. Its flour is rich in protein (9.6%) with fairly balanced essential amino acid content and has a chemical score of 0.94. The starch granules have been reported to have a polygonal or spherical shape (<10 μm) [12]. Also, the nutritional quality of its flour for growing rat, tuber hardening phenomenon as well as changes in its antinutritional factors after harvest have been studied [12,13]. Furthermore, the use of starches from C. bicolor and D. dumentorum as dual purpose polymer additive [14] and their suitability for the synthesis of biodegradable starch plastics have been documented [8]. Inspite of their abundance, little information exist on the properties of its starches. The present study was therefore carried out to evaluate the physicochemical, functional and antinutritional properties of starches extracted from wild C. bicolor and D. dumentorum. This information could be used to access the suitability of starches from these plants for industrial applications. ABSTRACT RESEARCH ARTICLE KEYWORDS European Journal of Chemistry ISSN 2153-2249 (Print) / ISSN 2153-2257 (Online) – Copyright © 2019 The Authors – Atlanta Publishing House LLC – Printed in the USA. This work is published and licensed by Atlanta Publishing House LLC – CC BY NC – Some Rights Reserved. http://dx.doi.org/10.5155/eurjchem.10.3.228-233.1833 http://dx.doi.org/10.5155/eurjchem.10.3.228-233.1833 https://crossmark.crossref.org/dialog/?doi=10.5155/eurjchem.10.3.228-233.1833&domain=pdf&date_stamp=2019-09-30 http://www.eurjchem.com/ http://dx.doi.org/10.5155/eurjchem.10.3.228-233.1833 mailto:basil_ita@yahoo.com mailto:ifioknuwem@gmail.com mailto:basil_ita@yahoo.com http://www.eurjchem.com/ https://crossmark.crossref.org/dialog/?doi=10.5155/eurjchem.10.3.228-233.1833&domain=pdf&date_stamp=2019-09-30� Uwem and Ita / European Journal of Chemistry 10 (3) (2019) 228-233 229 Table 1. Physicochemical properties of starches from C. bicolor and D. dumentorum. Variable * C. bicolor D. dumentorum Starch yield (%) 66.18±0.37 68.13±0.25 Moisture content (%) 7.65± 0.04 10.29±0.04 pH (20% slurry) 4.38± 0.05 4.09±0.04 Particle size (μm) 2-5 1-5 Ash content (%) 2.85±0.03 2.31±0.04 Crude lipid (%) 0.12±0.01 0.15±0.02 Crude protein (%) 0.11±0.01 0.13±0.01 Crude fibre (%) 2.85±0.12 3.39±0.21 Carbohydrate content (%) 83.57±7.11 82.62±8.22 Amylose content (%) 17.68±0.11 14.93±0.14 Amylopectin (%) 82.33±0.36 85.08±0.23 * Mean of triplicate determinations. 2. Experimental 2.1. Sample collection Wild species of cocoyam (C. bicolor) and three leaf yam (D. dumentorum) were harvested from the wild within Uyo Local Government Area of Akwa Ibom State, Nigeria. The roots were thoroughly washed, peeled, sliced, grated and dried to homogenous flour. 2.2. Starch extraction The modified method of Adikwu [15] was used. Briefly, 80 g of each sample was soaked in distilled water for 30 mins and filtered using a cheese cloth. This process was repeated four times and the filtrates combined, and then allowed to settle for 6 hrs. On complete sedimentation, the supernatant was discarded to obtain the starch, which was soaked in distilled water containing 0.1% Na2SO3 (w:v) for 24 hrs. After this, the starch was re-extracted with 70 mL of 0.1 M NaOH for 24 hrs and 70 mL of 0.1 M H2SO4 for 12 hrs. The obtained starch was dried at 60 °C for 12 hrs, weighed and stored in an air-tight container. The percentage starch in each sample was determined using the Equation 1. Weight of dry starch% Starch yield 100 Weight of dry flour = × (1) 2.3. Proximate analysis Crude fibre, lipid, protein, carbohydrate and ash content of the isolated starches were determined by The Official Methods of Analysis of AOAC International methods [16]. 2.4. pH determination An electronic pH meter which has been standardized using buffer solutions 4 and 9, respectively, was used to determine the pH of the isolated starches (20% slurry). 2.5. Determination of particle size This was determined using an Olympus laboratory microscope equipped with a graticule and camera. 70% of iodine solution in alcohol was added to 1% starch solution of each sample and placed in a glass slide with a glass cover slip and viewed under the microscope. A 40× objective lens and a 10× eyepiece were employed. The particle size of the starch grains were recorded with the help of the microscope graticule [17]. 2.6. Determination of amylose and amylopectin content The modified method of Mojzoobi et al. [18] was used to determine the amylose and amylopectin content of the isolated starches. 2.7. Antinutrient determination Oxalate content of the starches was determined using the method of Ritter and Savage [19]. Tannins were evaluated using the method of Pearson [20]. Phytate was evaluated using the method of Nkama and Gbenyi [21]. Hydrogen cyanide was determined by the AOAC method [16]. 2.8. Functional, pasting and thermal properties Starch dispersibility was determined by the method described by Kulkarni, et al. [22]. Swelling power and solubility was evaluated at a concentration of 2% (w:v) at 90 °C in accordance with Nwokocha and Williams [23]. The centrifugal method of Beuchat [24] was used to determine the oil and water absorption capacity of the isolated starch samples. To evaluate the pasting properties of the samples (6%, w/w), a rapid viscoanalyser (Newport Scientific, RVA 4, Australia) was used. The pasting temperature (Ptemp), peak viscosity (PV), trough viscosity (TV), breakdown viscosity (BV), final viscosity (FV) and setback viscosity (SV) were recorded in accordance with the method of Sandhu and Singh [25]. Gelatinization temperature of the samples was determined using differential scanning calorimeter (DSC) (Perkin-Elmer DSC-7, Norwalk, CT). The enthalpy change of gelatinization (ΔHgel), onset (To), peak (Tp) and conclusion (Tc) temperatures of the gel were recorded [4]. 2.9. IR spectra IR spectra of the samples were carried out using an IR spectrometer (Shanghai S410, NIR Infrared). 3. Results and discussion 3.1. Physico-chemical properties Wild C. bicolor and D. dumentorum grows abundantly in the south east and south south regions of Nigeria. Since they are not consumed, they represent an underutilised biomass that could be exploited for industrial purposes. As presented in Table 1, D. dumentorum had slightly higher starch yield (68.13±0.25%) than C. bicolor (66.18±0.37%). These were higher than Manihot esculenta (cassava), Dioscorea hispida and Ipeoma batatas (sweet potato) [2] but lower than reports by Alobi et al. [8]. These results suggest that C. bicolor and D. dumentorum flours are rich sources of starch that could be utilized industrially. Moisture content was lower in C. bicolor (7.65±0.04) than D. dumentorum (10.29±0.04); however, both were lower than the recommended safe storage range of <13 %, suggesting their suitability as commercial starch [18,26]. The pH of the starch slurry (20%) showed they are acidic (4.09±0.04-4.38±0.05) and was lower than D. hispida (4.48±0.03), M. esculenta (5.55±0.01), Solanum tuberosum (6.22±0.00), but higher than D. pyrifolia (3.43±0.05). 2019 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.10.3.228-233.1833 230 Uwem and Ita / European Journal of Chemistry 10 (3) (2019) 228-233 Table 2. Functional, pasting and thermal properties of starches from C. bicolor and D. dumentorum. Variable* C. bicolor D. dumentorum Functional properties Dispersibility (%) 53.49±0.01 64.85±0.07 Swelling power (g/g) 78.50±0.05 53.20±0.28 Solubility (% ) 41.60±0.50 73.99±0.93 Water absorption capacity (g/g) 2.05±0.01 1.06±0.01 Oil absorption capacity (g/g) 1.56±0.01 2.15±0.01 Gelatinization characteristics To (°C) 63±0.4 69±0.3 Tm (°C) 67±0.4 76±0.4 Tc (°C) 75±0.5 79±0.4 ΔHgel (J/g) 10.07 12.14 R 12 10 Pasting properties Ptemp (oC) 69±0.3 75±0.4 PV (cP) 3033±48.1 3214±50.3 TV (cP) 1478±36.5 1782±27.5 BV (cP) 987±23.4 1135±30.1 SV (cP) 1395±44.9 1441±21.9 FV (cP) 2736±57.3 3574±44.7 * Mean of triplicate determinations; T o = Onset gelatinisation temperature; Tm = Midpoint gelatinisation temperature; Tc = Conclusion gelatinisation temperature; R = Gelatinisation temperature range; ΔHgel = Enthalpy of gelatinization; Ptemp = Pasting temperature; PV= Peak viscosity; TV = Trough viscosity; BV = Breakdown viscosity; SV= Setback viscosity; FV = Final viscosity. The starches had very small granule size, 1-5 μm [27]. C. bicolor and D. dumentorum starches had high ash contents (2.85±0.03 and 2.31±0.04%, respectively); these were higher than the recommended industry standard (0.5% ash) and reports by Alobi et al. [8]. This variation may be due to environmental factors, genetic mutation, processing and storage conditions. Lipid and protein were generally low, with C. bicolor (0.12±0.01 and 0.11±0.01%, respectively) having lower contents than D. dumentorum (0.15±0.02 and 0.13± 0.01%, respectively). These were lower than Chinese sweet potatoe, mung bean, D. alata and D. esculenta [2,28]. Low lipid and protein content of the isolated starches indicates high purity and quality. Also, high protein and lipid results in low clarity of starch paste and represses starch granule swelling [28,29]. Carbohydrate was similar in both starches (83.57±7.11 and 82.62±8.22% for C. bicolor and D. dumen- torum, respectively) and did not differ significantly. However, they were lower than D. pyrifolia (92.73±0.48%), D. alata (86.81±1.33%), Ipeoma batatas (92.20±1.08%) but higher than Solanum tuberosum (80.22±0.00%) [2]. Crude fibre was slightly higher in D. dumentorum (3.39±0.21%) than C. bicolor (1.85±0.12%). Lower values have been reported for Zea mays, Solanum tuberosum, Metroxylan sagu and sweet potatoes, while higher values have been reported for mung beans [2,5]. 3.2. Amylose and amylopectin content Amylose and amylopectin content of the starches are given in Table 1. These are the two major components of starch granules and greatly affect the function of starch such as swelling, solubility, pasting, gelatinization, etc. Amylose has the proclivity for strong films and gels and to retrograde, while amylopectin forms softer gels and films when dispersed in water [9]. Generally, the starches had low amylose content, with C. bicolor being slightly higher (17.68±0.11%) than D. dumentorum (14.93±0.14%). Higher amylose contents have been reported for D. pyrifolia (44.47±1.86%), D. opposite (20.65±0.15%), S. tuberosum (26.90±0.08%), L. meyenii ecotypes (21.00-21.30±0.00%); similar values have been reported for D. bulbifera (17.61±0.13%), D. nipponica (17.67± 0.33%), while lower value is reported for D. septemloba (13.58±0.10%) [2,4]. The low amylose content observed in our starches suggests use in situations where soft gels/films are needed such as in the glue, detergent, plywood and textile industry. 3.3. Functional, pasting and thermal properties Dispersibility of starch measures its degree of reconstitution in water. The higher its dispersibility, the better it reconstitutes in water [23]. D. dumentorum had a higher dispersibility (64.85±0.07%) than C. bicolor (53.49±0.01%) as given in Table 2. Higher dispersibility value has been reported for rice (87.01%), cassava (84.00%) and potato (86.00%) starch [30,31], while a lower value has been reported for breadfruit (40.67%) starch [32]. Swelling power and water solubility index provides evidence of the magnitude of interaction between starch chains with both the amorphous and crystalline domains [33], and gives a measure of the hydration status of starch molecules. C. bicolor starch had a higher swelling power (78.50±0.05 g/g) and lower solubility (41.60±0.05%) than D. dumentorum (53.20±0.28 g/g and 73.99±0.93%, respectively). Lower swelling power has been reported for D. bulbifera, D. alata, D pyrifolia, D opposite and cereals [3]. The extent of cross-bonding within the granules and the presence of lipids or phosphates affect the swelling and solubility profiles of starches. The high swelling power and solubility index exhibited by these starches may be attributed to its low amylose content and low lipid content as high amylose content and strong intermolecular bonds reduce swelling [5]. These suggest that these starches may find application in adhesives, pastes and glues in the non-food industries [34]. Water absorption capacity of the starches varied between 1.06±0.00 g/g and 2.05±0.01 g/g, with C. bicolor having a higher capacity than D. dumentorum (Table 2). The water absorption capacity of C. bicolor was higher than D. opposite (1.41±0.01 g/g), D. alata (1.56±0.11 g/g), but lower than D. pyrifolia (2.45±0.23 g/g), D. bulbifera (2.53±0.02 g/g) and D. septemloba (5.57±0.03 g/g). Water absorption capacity of C. bicolor and D. dumentorum starches is affected by the extent of hydrogen bonding between water molecules and starch hydroxyl groups as well as loose association between amylose and amylopectin molecules in starch granules [2,3]. Oil absorption capacity was higher in D. dumentorum (2.15±0.01 g/g) than C. bicolor (1.56±0.01 g/g). The oil absorption capacity of our starches was higher than rice and corn starches (1.09±0.03 to 1.1±0.03 g/g and 0.08±0.08 to 0.85± 0.07 g/g, respectively) grown in Indian temperate climate as well as tartary buckwheat starch (92.48±12.19 g/g) [6,34]. 2019 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.10.3.228-233.1833 Uwem and Ita / European Journal of Chemistry 10 (3) (2019) 228-233 231 Figure 1. Antinutrient composition of starches from Caladium bicolor and Dioscorea dumentorum. These result indicate that our starches can effectively absorb oil arising from the interaction between non polar amino acid side chain and hydrocarbon lipid chains within the starch granules, thereby enhancing mouth feel and flavour retention [6,34]. The starches formed odorless gels with similar viscosity, although D. dumentorum was slightly higher (1.48±0.01%) than C. bicolor (1.29±0.01%). Gelatinization temperatures (onset To, midpoint Tm and conclusion Tc), enthalpy change of gelatinization (ΔHgel) and gelatinization range (R) for the starches are given in Table 2. D. dumentorum had a higher gelatinization temperature (To = 69±0.3 °C, Tm = 76±0.4 °C, Tc = 79±0.4 °C) and enthalpy of gelatinization (ΔHgel=12.14 J/g) than C. bicolor (To = 64±0.3 °C, Tm = 67±0.4 °C, Tc = 75±0.4 °C; ΔHgel = 10.07 J/g), but with a shorter range (R = 10). Higher gelatinization temperatures have been reported for D. opposite, D. pyrofolia, D. alata [2], while lower gelatinization temperatures have been reported for maca starch [4] mung bean and potato [2]. According to Jiang et al. [3] gelatinization of starch is affected by the molecular arrangement of the crystalline region bearing the amylopectin chains and not the amylose-amylopectin ratio. In addition, variables such as amylose content, complexes formed by interaction between lipids and amylose chains, size and shape of the starch granules as well as the distribution of the amylopectin chains also affect the gelatinization charac- teristics of starches. D. dumentorum had higher pasting (3214±50.3 cP), trough (1782±27.5 cP), breakdown (1135±30.1 cP), final (3574±44.7 cP) and setback viscosity (1441±21.9 cP) than C. bicolor. In addition, a higher pasting temperature was observed for D. dumentorum (75±0.4 °C) than C. bicolor (69±0.3 °C) (Table 2). This variation may be attributed to the molecular structure of their amylopectin chain, amylose content as well as their granular architecture. Higher values have been reported for maca starch [4] while lower values have been reported for corn starch [25]. 3.4. Antinutrient composition Levels of antinutrients in the isolated starches are given in Figure 1. HCN was higher in D. dumentorum (810.40±2.96 mg/100 g) than C. bicolor (194.85±0.48 mg/100 g). Samuel et al. [36] reported 6.54 mg/kg for tapioca flour. Ndidi et al. [37] reported HCN level of 224.03±2.54 mg/kg for African yam bean (Sphenostylis stenocarpa) seeds. Our results indicate high level of HCN in the starches above permissible levels. High HCN is capable of inhibiting cytochrome C oxidase, which can lead to cytotoxic hypoxia [38]. The high level of HCN may be due to the fact that during starch isolation, heat treatment was not involved, as antinutrients are heat labile and deactivated during processing protocols requiring heat treatment [39]. Tannins was higher in C. bicolor (254.97±0.42 mg/100 g) than D. dumentorum (144.71±0.06 mg/100 g). In comparison with other works, lower tannin levels are reported for edible trifoliate yam (22.00±0.00 mg catechin equivalent /100 g), tapioca (0.01%), cocoyam (0.05 g/100 g) and yellow yam (0.01±0.00 mg/100 g) [12,35,36,40]. However, our results were within permissible limits [37]. High oxalate levels were found in the starches. Total oxalate was higher in D. dumentorum (844.10±14.57 mg/100 g) than C. bicolor (153.16±18.15 mg/100 g). D. dumentorum also had higher levels of soluble and insoluble oxalates than C. bicolor (Figure 1). Samuel et al. [36] reported high oxalate level of 0.6% for tapioca, while Medoua et al. [12] reported 502-512 mg/100 g for D. dumentorum from Cameroun. In addition, high oxalate levels (780 mg/100 g) have been reported for taro corms [41]. High oxalate levels in diet interfere with mineral absorption and have been implicated in kidney stones [42]. Phytate levels were low and within permissible limits. It ranged from 0.24±0.06 mg/100 g to 4.66±0.05 mg/100 g, with D. dumen- torum having the higher level. Higher values have been reported for tubers, legumes and cereals [12,35-37], while phytate level of 0.05±0.00 mg/100 g has been reported for Dioscorea cayenensis [39]. Phytates are known to bind mineral nutrients in the digestive tract leading to mineral deficiency in the body [43]. Overall, the starches had comparatively high levels of HCN, tannins and oxalates; suggesting their suitability for non-food applications. 3.5. Moisture sorption behavior Moisture sorption behavior of C. bicolor and D. dumentorum is given in Figure 2. Result showed increased hygroscopy with exposure time. After 24 hrs, C. bicolor and D. dumentorum sorped 0.420 and 0.62 g of moisture, respectively. However, this decreased with increasing exposure time. At 120 hrs, moisture sorped was 0.016 and 0.017 g for C. bicolor and D. dumentorum, respectively; this equilibrated to 0.002 g for both samples at 192 hrs. D. dumentorum sorped more moisture between 24 to 120 hrs, while C. bicolor sorped more moisture after 120 hrs, until it equilibrated at 192 hrs. Our result is in agreement with reports for maize starch at 33% relative humidity for 186 hrs [35]. This result suggests that under atmospheric conditions, our starches are sensitive to atmospheric moisture. 2019 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.10.3.228-233.1833 232 Uwem and Ita / European Journal of Chemistry 10 (3) (2019) 228-233 Table 3. Infrared frequencies (cm-1) of starches from C. bicolor and D. dumentorum. C. bicolor Assignment D. dumentorum Assignment 3378 O-H stretch 3282 O-H stretch 1702 C=O stretch 2927 C-H stretch 1626 Adsorbed water 1640 Adsorbed water 1149 C-O stretch 1422 C-O-H bend 1034 1355 C-H out-of-plane 865 CH, CH2 deform. 1202 669 1149 C-O stretch 576 913 860 CH, CH2 deform. 766 Figure 2. Moisture sorption behaviour of starches from Caladium bicolor and Dioscorea dumentorum. 3.6. IR spectroscopy The observed bands for C. bicolor and D. dumentorum are given in Table 3. In the O-H stretching region, peaks were observed at 3282 cm-1 (broad) for D. dumentorum and 3378 cm-1 for C. bicolor. Because the C-H stretching vibrations occur in a very narrow region, overlap of bands may occur. C-H stretching frequency was observed at 2927 cm-1 for D. dumentorum, but absent in C. bicolor. This situation may be explained in terms of band interferences or overlap as well as the effect of α-D-glucose on the α-1,4-backbone and α-1,6- branch structure of the amylopectin moiety, causing a shift in the C-H stretching vibration of C. bicolor. Santha et al. [44] reported similar observation for the IR spectra of sweet potato and cassava starch. In the mid-range region, the bands at 1640 and 1626 cm-1 for D. dumentorum and C. bicolor respectively, may be attributed to adsorbed water [44], suggesting vibrations of adsorbed water molecules in the non -crystalline portion of the starches, while the band at 1702 cm-1 observed in C. bicolor may be due to minor component (lipids or protein) present in the sample. In the fingerprint region, peaks between 1100 and 1150 cm-1 may be attributed to C-O, C-C and C-O-H stretching, while peaks between 1100 and 900 cm-1 may be attributed to C-O-H bending modes. Peaks at 860 and 865 cm-1 in D. dumentorum and C. bicolor correspond to CH and CH2 deformation modes. Similar results have been reported for potato starch [45]. However, it should be noted that in the IR spectra of starches, absorbance bands overlap and may be poorly resolved, hence it becomes difficult to assign bands unambiguously [46]. 4. Conclusion Starch isolated from C. bicolor and D. dumentorum had variable physicochemical, functional, thermal, pasting and antinutrient properties. Moisture and amylopectin content was higher in D. dumentorum than C. bicolor, while carbohydrate content was similar. In addition, both starches had good swelling power, dispersibilty, oil and water absorp- tion capacity as well as thermal and pasting properties. However, their high antinutrient content possesses a challenge to its use in the food industry. This suggests that these starches may find great use in paper making, adhesives, textile and other non-food applications. Acknowledgement The authors are grateful to the technologist at the Department of Chemistry, University of Uyo, Nigeria, for technical support. Disclosure statement Conflict of interests: The authors declare that they have no conflict of interest. Author contributions: All authors contributed equally to this work. Ethical approval: All ethical guidelines have been adhered. Sample availability: Samples of the compounds are available from the author. ORCID Basil Nse Ita http://orcid.org/0000-0002-3965-3493 Ifiok Nseobong Uwem http://orcid.org/0000-0001-9845-1034 References [1]. Adebowale, K. O.; Lawal, O. S. J. Food Sci. Agric. 2003, 83, 1541-1545. [2]. Elmi Sharlina, M. S.; Yaacob, W. A.; Lazim, A. M.; Fazry, S.; Lim, S. J.; Abdullah, S.; Noordin, A.; Kumaran, M. Food Chem. 2017, 220, 225- 232. [3]. Jiang, Q.; Gao, W.; Li, X.; Xia, Y.; Wang, H.; Wua, S.; Xiao, P. Food Hydrocoll. 2012, 29, 35-41. [4]. Zhang, L.; Li, G.; Wang, S.; Yao, W.; Zhu, F. Food Chem. 2017, 218, 56- 63. [5]. Jiang, Q.; Gao, W.; Shi, Y.; Li, X.; Wang, H.; Huang, L.; Xiao, P. Food Hydrocoll. 2013, 32, 432-439. 2019 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.10.3.228-233.1833 http://orcid.org/0000-0002-3965-3493 http://orcid.org/0000-0001-9845-1034 Uwem and Ita / European Journal of Chemistry 10 (3) (2019) 228-233 233 [6]. Ali, A.; Wani, T. A.; Wani, I. A.; Masoodi, F. A. J. Saudi Soc. Agric. Sci. 2016, 15, 75-82. [7]. Singh, H.; Sorhi, N.; Singh, N. Intl. J. Food Sci. 2009, 12, 713-725. [8]. Alobi, N. O.; Sunday, E. A.; Magu, T. O.; Okolo, G. O.; Nyong, B. E. J. Bas. Appl. Res. 2017, 3(1), 27-32. [9]. Ashogbon, A. O. Intl. J. Biotech. Food Sci. 2014, 2(5), 94-101. [10]. Odugbemi, T. Outlines and pictures of medicinal plants in Nigeria. University of Lagos Press, 2006. [11]. Amadi, O. C.; Onyema, N.; Nwagu, T. N.; Moneke, A. N.; Okolo, B. N.; Agu, R. C. Proc. Environ. Sci. 2016, 35, 809-817. [12]. Medoua, G. N.; Mbome, J. L.; Agbor-Egbe, T.; Mbofung, C. M. F. Food Chem. 2007, 102, 716-720. [13]. Lape, I. M.; Treche, S. J. Sci. Food Agric. 1994, 66, 447-455. [14]. Umoren, S. A. J. Appl. Sci. Environ. Manag. 2005, 9(1), 75-78. [15]. Adikwu, M. U. Nig. J. Nat. Prod. Med. 1998, 2, 54-56. [16]. Association of Official Analytical Chemist. AOAC. Methods of Analysis of AOAC, 18th edition, Washington D. C, 2012. [17]. Ogbode, O.; Okeke, C. N.; Otashu, M. Indian J. Eng. Mat. Sci. 1997, 72(4), 134-138. [18]. Mojzoobi, M.; Rowe, A.; Connock, M.; Hill, G.; Harding, E. Carbohydr. Polym. 2003, 52, 269-274. [19]. Ritter, M. M. C.; Savage, G. P. J. Food Comp. Anal. 2007, 20, 169-174. [20]. Pearson. D. A. Chemical Analysis of Foods, 7th edition, Churchill Livingstone, 1976. [21]. Nkama, A.; Gbenyi, I. Nig. Trop. J. Agric. 2001, 3, 270-271. [22]. Kulkarni, K. O.; Kulkarni, D. N.; Ingle, U. M. Food. Nutr. Bull. 1991, 13(4), 322-327. [23]. Nwokocha , L. M.; Williams, P. A. Carbohydr. Polym. 2009, 78, 462- 468. [24]. Beuchat, L. R. J. Agric. Food Chem. 1977, 25, 258-261. [25]. Sandhu, K. S.; Singh, N. Food Chem 2007, 101, 1499-1507. [26]. Indian Standards. Specifications for tapioca starch for use in cotton textile industries, IS 1605-1960. New Delhi: Indian Standard Institution, 1970. [27]. Lindeboom, N.; Chang, P. R.; Tyler, R. T. Starch-Starke 2004, 56, 89- 99. [28]. Chen, Z.; Schols, H. A.; Voragen, A. G. J. J. Food Sci. 2003, 68(2), 431- 437. [29]. Blazck, J.; Copeland, L. Carbohydr. Polym. 2008, 71(3), 380-387. [30]. Ashogbon, A. O.; Akintayo. E. T. Intl. Food Res. J. 2012, 19(2), 665-671. [31]. Eke-Ejiofor, J.; Owuno, F. Intl. J. Nutr. Food Sci. 2014, 3(6), 567-571. [32]. Akanbi, T. O.; Nazamid, S.; Adebowale, A. A. Intl. Food Res. J. 2009, 16, 151-157. [33]. Tang, H.; Mitsunaga, T.; Rawamara, Y. Carbohydr. Polym. 2004, 57, 145-152. [34]. Sindhu, R.; Khatkar, B. S. Intl. J. Eng. Res. Tech. 2016, 5(6), 315-320. [35]. Adebayo, A. S.; Itiola, O. A. Nig. J. Nat. Prod. Med. 1998, 2, 27-33. [36]. Samuel, F. O.; Otegbayo, B. O.; Alalade, T. Food Nutr. Sci. 2013, 3, 784- 789. [37]. Ndidi, U. S.; Ndidi, C. U.; Olagunju, A.; Muhammad, A.; Billy, F. G.; Okpe, C. ISRN Nutr. 2014, 4, 1-9. [38]. Okafor, P. N.; Anyanwu, V. O.; Onyema, H. O. J. Pharm. Toxicol. 2006, 1, 40-46. [39]. Adepoju, O. T.; Boyejo, O.; Adeniji, P. O. Food Chem. 2018, 238, 160- 165. [40]. Bamidele, O. P.; Ogundele, F. G.; Ojubanire, B. A.; Fasogbon, M. B.; Bello, O. W. Food Sci. Nutr. 2014, 2(6), 706-711. [41]. Holloway, W. D.; Argall, M. E.; Jealous, W. T.; Lee, J. A.; Bradbury, J. H. J. Agric. Food Chem. 1989, 37, 337-341. [42]. Chai, W.; Liebman, M. J. Nutr. 2004, 172, 953-957. [43]. Thompson, l. U. Food Res. Intl. 2003, 26, 131-149. [44]. Santha, N.; Sudha, K. G.; Vijayukuman, K. P.; Nayar, V. U.; Moorthy, S. N. Proc. Indian Acad. Sci. (Chem. Sci.) 1990, 102(5), 705-712. [45]. Cael, J. J.; Koenig, J. L.; Blackwell, J. Biopolymers. 1975, 14, 1885- 1890. [46]. Van Soest, J. J.; Vliegenthart, J. F. Trends Biotech. 1997, 15(6), 208- 213. Copyright © 2019 by Authors. This work is published and licensed by Atlanta Publishing House LLC, Atlanta, GA, USA. The full terms of this license are available at http://www.eurjchem.com/index.php/eurjchem/pages/view/terms and incorporate the Creative Commons Attribution-Non Commercial (CC BY NC) (International, v4.0) License (http://creativecommons.org/licenses/by-nc/4.0). By accessing the work, you hereby accept the Terms. This is an open access article distributed under the terms and conditions of the CC BY NC License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited without any further permission from Atlanta Publishing House LLC (European Journal of Chemistry). No use, distribution or reproduction is permitted which does not comply with these terms. Permissions for commercial use of this work beyond the scope of the License (http://www.eurjchem.com/index.php/eurjchem/pages/view/terms) are administered by Atlanta Publishing House LLC (European Journal of Chemistry). 2019 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.10.3.228-233.1833 http://www.eurjchem.com/index.php/eurjchem/pages/view/terms http://creativecommons.org/licenses/by-nc/4.0 http://www.eurjchem.com/index.php/eurjchem/pages/view/terms 1. Introduction 2. Experimental 2.1. Sample collection 2.2. Starch extraction 2.3. Proximate analysis 2.4. pH determination 2.5. Determination of particle size 2.6. Determination of amylose and amylopectin content 2.7. Antinutrient determination 2.8. Functional, pasting and thermal properties 2.9. IR spectra 3. Results and discussion 3.1. Physico-chemical properties 3.2. Amylose and amylopectin content 3.3. Functional, pasting and thermal properties 3.4. Antinutrient composition 3.5. Moisture sorption behavior 3.6. IR spectroscopy 4. Conclusion Acknowledgement ORCID References PrintField10: PrintField11: PrintField12: PrintField13: PrintField14: PrintField15: PrintField20: PrintField21: PrintField22: PrintField23: PrintField24: PrintField25: