Chemical Composition of the Marc of a Wild Tropical Plant <i>Tacca involucrata</i> (Schumach and Thonn, 1827)

Abstract

Tacca involucrata (Batflower or Polynesian arrowroot) tubers are a stable food in tropics where it occurs. In central Nigeria, it is processed locally after digging it from the ground by peeling with sharp sand, grating and soaking in fresh water after which it is filtered and the filtrate is dried and is cooked with other ingredients. The marc, said to be bitter, is usually discarded by deep burial as it is considered poisonous to livestock and humans. All parts of the plant are used in folk medicine to treat various diseases. The aim of this work was to analyze quantitatively the phytochemical, elemental, vitamin and proximate composition of the marc of the tubers with a view of assessing its pharmacological and nutritional potentials. The marc was obtained from Jandeikyura Village in Wukari LGA of Taraba State, Nigeria, and was extracted with 80% methanol for 72 hr to give a yield of 10.1% w/w and was whitish in colour. Phytochemical analysis showed the presence of reducing sugars, tannins, flavonoids, steroids, glycosides and hydrogen cyanide at 195.65 ± 0.5, 3.44 ± 0.2, 1.29 ± 0.5, 0.83 ± 0.4, 1.36 ± 1.0 and 0.00985 ± 0.3 (mg/100g), respectively. The elemental analysis showed the presence of potassium, sodium, magnesium, selenium, manganese, vanadium and some heavy metals like lead, aluminium, arsenic and mercury at 36.45 ± 0.1, 44.04 ± 0.1, 1.52 ± 0.2, 0.80 ± 0.9, 0.52 ± 0.7, 0.27 ± 0.7, 0.07 ± 0.6, 0.008 ± 0.05, 0.085 ± 0.6 and 0.026 ± 0.6 (mg/100g), respectively. Vitamin analysis showed the presence of vitamins A, B1, B2, B3, C and E in various amount as 2.26 ± 0.8 µg, 0.83 ± 0.8 mg/100g, 0.58 ± 0.4 mg/100g, 0.33 ± 0.6 mg/100g, 9.80 ± 0.4 mg/100g and 6.86 ± 0.9 mg/100g, respectively. The proximate analysis showed the marc to contain moisture, ash, fats, fibre, crude protein and carbohydrate in the range of 10.83% ± 0.3%, 1.93% ± 0.6%, 1.06% ± 0.5%, 4.42% ± 0.4%, 6.12% ± 0.6% and 86.07% ± 0.3%, respectively. This shows that despite the presence of hydrogen cyanide and some heavy metals in traces amount which are considered poisonous to livestock and humans, the marc contains some elements, vitamins, phytochemical and nutrients which are pharmacologically and nutritionally important.

Phytochemical characterization of forest leaves extracts and application to control apple postharvest diseases

“…It increases, as there are more carbon atoms and as chains get longer. The refractive index indicates that the sample may contain an unsaturated long carbon chain 44 . Measurements of the refractive index are particularly useful for determining the purity of volatile and fixed oils 45 .…”

Prospects for Industrial Utilization of Tacca (Tacca involucrata) in Nigeria

“…As a result tacca roots are found in local markets in many communities where they are traded and provide income for people harvesting, processing and trading in them. Bosha et al (2015) in a study carried out on the phytochemical analysis of tacca, reported the presence of reducing sugars, tannins, flavonoids, steroids, glycosides and hydrogen cyanide at 195.65 ± 0.5, 3.44 ± 0.2, 1.29 ± 0.5, 0.83 ± 0.4, 1.36 ± 1.0 and 0.00985 ± 0.3 (mg/100g), respectively. According to the authors, The elemental analysis of the root showed it to contain potassium, sodium, magnesium, selenium, manganese, vanadium and some heavy metals like lead, aluminium, arsenic and mercury at 36.45 ± 0.1, 44.04 ± 0.1, 1.52 ± 0.2, 0.80 ± 0.9, 0.52 ± 0.7, 0.27 ± 0.7, 0.07 ± 0.6, 0.008 ± 0.05, 0.085 ± 0.6 and 0.026 ± 0.6 (mg/100g), respectively.…”

Nutritional evaluation of flour obtained from Tacca leontopetaloides used as an alternative food in Muanza-Mozambique

“…The flour from T. leontopetaloides of the present work was very rich in ash, compared with previous works by other authors (Tables 1 and 4), providing an indication of its richness in minerals. As macrominerals make up more than 0.005% of the human body and we require more than 100 mg of macrominerals per day , including calcium, magnesium, phosphorus, potassium, sodium and sulphur (Hark, 2005), the flour from T. leontopetaloides has potential to meet this dietary requirement, making it a good resource as food and feed (Bosha et al, 2015). Nevertheless, we observed that the method used to obtain the flour plays a major role not only in its ash content, but also in its mineral composition (Table 2).…”