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Biochemical Characterization and Nutritional Value of Peanut (Arachis Hypogaea L.) Leaves, Taro (Colocasia Esculenta L. Schott) and Pigeon Pea (Cajanus Cajan L. Huth)

OSSOKO Jean Paul Latran*, OKANDZA Yves, TONI née GANONGO- PO Fanny, DELLAU Henrina, DZONDO Gadet Michel, MVOULA TSIERI Michel Didace

Laboratoire de Contrôle et Qualité des Aliments (ENSAF, Université Marien NGOUABI)

Abstract: Among the least consumed local vegetables in Congo are peanut leaves (Arachis hypogea L.), pigeon pea leaves (Cajanus cajan L.Huth), and taro leaves (Colocasia esculenta L. Schott). Thus, the general objective of this study, which is to establish the biochemical characterization and nutritional value of peanut (Arachis hypogaea), pigeon pea (Cajanus cajan) and taro (Colocasia esculenta) leaves, among other things, was to use the standards established by the AOAC to achieve this objective, namely: the oven to determine the water content, the Soxhlet method to extract the fat, the Kjeldahl method to determine the total protein content, the muffle furnace to know the ash content, we deduced the carbohydrates content and finally we used spectrometry to identify the minerals in the ash. We obtained the following results: A. hypogaea: Water: 80.93±1.83%; Lipids: 1.46±0.12%; Proteins: 1.83±0.08%; Carbohydrates: 15.40±1.84%; Ash: 0.62±0.001%; Energy: 81.26±5.86 Kcal/100g. C. esculenta: Water: 84.89±0.57%; Fat: 1.32±0.07%; Protein: 0.88±0.01%; Carbohydrates: 11.54±0.57%; Ash: 1.37±0.01%; Energy: 61.55±2.43 Kcal/100g. C. cajan: Water: 68.13±0.46%, Fat: 0.38±0.13%; Protein: 23.00±0.33%; Carbohydrates: 6.44±0.67%; Ash: 2.16±0.02%; Energy: 120.94±1.56 Kcal/100g. Among the minerals sought, magnesium, calcium, potassium, and sodium are the most abundant in all the leaves studied. Pigeon pea leaves are the richest in protein and can be used more widely outside of their use as a forage plant.

Keywords: Study, Edible Leaves, Nutritional Value, Congo, Mineral Fraction.

Received April 14, 2025; Revised May 15, 2025; Accepted May 23, 2025

Citation: OSSOKO Jean Paul Latran, OKANDZA Yves, TONI née GANONGO- PO Fanny, DELLAU Henrina, DZONDO Gadet Michel, MVOULA TSIERI Michel Didace, Biochemical Characterization and Nutritional Value of Peanut (Arachis Hypogaea L.) Leaves, Taro (Colocasia Esculenta L. Schott) and Pigeon Pea (Cajanus Cajan L. Huth). American Journal of Food and Nutrition, 13 (3). 74-79. January 2025. doi:10.12691/ajfn-13-3-1

1. Introduction

The foods consumed by humans are classified into three main groups: energy-producing foods (tubers, grains, oils, butter, etc.), building foods (legumes, meat, fish, milk, eggs, etc.), and protective foods (fruits, vegetables, green leaves, etc.), each contributing in its own way to human nutritional balance [1]. Green leaves are particularly important because they play a role not only as a maintenance food and a bulking agent that facilitates digestion, but also in the growth and development of the body. Nutritionally, green leaves are an important source of vitamins and minerals that the body needs to maintain health [1]. In Congo, several leafy vegetables are grown. Among the most consumed are the leaves of cassava Manihot esculenta (Saka-saka), the leaves of Gnetum africanum (Mfumbua) and the leaves of Hibiscus sabdarifa (Guinea sorrel). However, there is a category of vegetables that are not widely consumed locally or regionally, among which we have the leaves of Arachis hypogaea, Colocasia esculenta and Cajanus cajan. The objective of this work is to develop a biochemical characterization in order to establish the nutritional value of the leaves of Arachis hypogaea, the leaves of Cajanus cajan and the leaves of Colocasia esculenta.

2. Materials and Methods

2.1. Plant Material

The plant material consisted of three types of fresh leaves, including Cajanus cajan leaves harvested in June in Brazzaville, Arachis hypogaea and Colocasia esculenta leaves purchased at the Mikalou market of Brazzaville from Lékana, in the Plateaux Department of the Republic of Congo.

Figure 1. Arachis hypogaea leaves (Henrina DELLAU, June 3, 2024)

Figure 2. Cajanus cajan leaves (Henrina DELLAU, June 4, 2024)

Figure 3. Colocasia esculenta leaves (Henrina DELLAU, June 5, 2024)

2.2. Methods

2.2.1. Physicochemical Characterization

2.2.1.1. Determination of Water Content (Wet Basis, WB)

To determine water content, 30 g (fresh mass) of each sample was weighed and then placed in an oven at 70°C. The oven was stopped when the sample mass remained constant.

Knowing the fresh mass (fm) and dry mass (dm) of the sample, the water content was determined using the following formula:

% Water = (mf-dm)/mf×100

2.2.1.2. Determination of Protein Content

Total nitrogen (protein) was determined using the Kjeldahl method.

The nitrogenous organic matter of the plant sample was mineralized using concentrated sulfuric acid. Nitrogen is recovered in ammonium form and then distilled in ammonia form before being measured by acid-base volumetric analysis.

In a matra, we introduced 0.5 grams of crushed and deoiled leaves, which we previously dried in an oven at 70°C for 24 hours. A spatula-shaped drop of mineralization catalyst and 10 mL of concentrated sulfuric acid were added, followed by a few glass beads and then placed on the mineralization ramp. Mineralization is carried out cold for 30 minutes. Then, it is heated to thermostat 7 and allowed to mineralize for 2 hours (hot mineralization). The supernatant should be clear and the residue white. We then cooled it, then added 20 mL of ultrapure water and 30 mL of sodium hydroxide at 400 g/L (until the solution turns brown). We steamed in the condenser by collecting the distillate in an Erlenmeyer flask or a 200mL flask containing 20mL of boric acid and a few drops of cresol green up to a volume of 125mL. We finally dosed the solution with N/20 sulfuric acid until the indicator (cresol green) turned from green to pink.

The protein content is determined using the following formula:

%N = (V H2SO4 x 0.07) / test sample

Protein content = %N x 6.25 (which is the multiplication factor)

2.2.1.3. Determination of Lipid Content

The oil extraction was carried out using the Soxhlet method [2] which is the reference method used for determining fat in dehydrated solid foods.

An empty 250 mL flask was weighed and its mass M₀ recorded. 200 mL of n-hexane was added to this flask. A cartridge containing a mass M equal to 15 grams of ground leaf material to be analyzed was placed in the extractor (Soxhlet). The extractor was positioned over the flask containing the elution solvent (hexane). The condenser, supplied with cold water, was placed on the extractor. After extracting the oil, the flask containing the solvent-oil mixture is recovered. The solvent is then separated from the oil using a rotary evaporator. Finally, the flask containing the oil is weighed and a new mass M₁ is recorded. The oil yield is calculated using the following formula:

%Lipids = (M1-M0)/M x 100

Where: %Lipids: lipid content (in %/100g DM); M: mass of the ground material (in g);

M0: mass of the empty flask (in g); M1: mass of the flask containing the oil (in g).

2.2.1.4. Determination of Crude Ash Content

Determining the ash content allows us to assess the mineral content of the sample. This operation consisted of incinerating the sample at a temperature of 550°C in an electrically heated muffle furnace until a constant mass was obtained. To do this, the empty crucibles were weighed, then 5g of the sample was weighed. The entire sample was placed in a muffle furnace for eight (8) hours. Afterwards, the crucible was allowed to stand until cooled, and then the crucible-sample assembly was weighed.

The ash content was determined using the following formula:

Ash content (% DM) = (M2-M0)/(M1-M0) × 100

Where:

M₀: mass in grams of the empty crucible. M₁: Mass in grams of the incineration crucible loaded with sample

M₂: Mass in grams of the incineration crucible loaded with ash.

2.2.1.4.1. Mineral Determination

Mineral determination is performed after determining the ash content. This operation consists of dissolving 0.5 g of ash from each sample in 10 ml of hyaluronic acid and 10 ml of lanthanum chloride. The solution is allowed to evaporate at 105°C in an incubator for 1 hour, then the residue obtained after evaporation is dissolved in 0.10 mol/L nitric acid. After filtering the solution, the metal contents are determined using the acetylated air flame atomic absorption technique. Each element is determined at a given wavelength.

The minerals measured are: Calcium (Ca), Magnesium (Mg), Sodium (Na), Potassium (K), Iron (Fe), Manganese (Mn), Copper (Cu) and Zinc (Zn).

2.2.1.5. Determination of Total Carbohydrate Content

Carbohydrate content is calculated by subtracting the sum of moisture, fat (MF), protein (P), and ash (C) from 100.

G = 100 – (H + P +MF +C)

2.2.7. Energy Value

The total energy value was calculated using the method of Manzi (1999) cited by Koffi et al. [3].

It is determined using the following formula:

VE (Kcal/100g) = (CHO x 4) + (CL x 9) + (CP x 4)

With CHO corresponding to the percentage (%) of carbohydrates, CL corresponding to the percentage (%) of lipids, and CP corresponding to the percentage (%) of proteins.

Expression of results. The Gauss-Laplace law method was used to determine the repeatability of the operations (three times) [4]. The following values were considered: mean, standard deviation (mean ± standard deviation). This was done using the Excel Pro 2019 spreadsheet.

2.2.2. Statistical Studies and Expression of Results

All measurements were carried out four times each. Statistical data processing was performed using the Excel spreadsheet, version 7. The results are expressed as mean ± SEM. Comparisons between multiple means were performed using analysis of variance (ANOVA)

3. Results and Discussion

3.1. Physicochemical Characteristics

The results of the analyses on the leaves studied are presented in Table 1 below.

The water contents of the different samples are very high and prove that it is freshly harvested plant material. Of these three species, C. esculenta has the highest water content (84.89±0.57%), followed by A. hypogaea (80.93±1.83%) and finally C. cajan (68.13±0.46%). The water contents of these species are higher than that of Gnetum africanum studied in the Republic of Congo [5]. These water contents are, however, low compared to Gbolo [Crassocephalum rubens (Juss. ex Jacq.) and C. crepidioides (Benth.)] studied in Benin and who found values ranging from 86.79± 0.04% for C. crepidioides to 87.95% ± 0.07% for C. rubens [6]. Yao et al., working on some of the most consumed leafy vegetables in Daloa in Ivory Coast, found very high levels in these vegetables ranging from 78.02 ± 0.25 to 93.75 ± 0.12% [7]. These levels are higher compared to the leaves of C. cajan. However, the water contents of C. esculenta and A. hypogaea are within this range. Mananga et al., working on A. hypogaea and C. esculenta in Congo had found lower water contents (27.19% for Arachis hypogaea and 30.23% for Colocasia esculenta) on the same species included in this present study [8]. This difference could be explained much more by the harvest period of the different samples and by the nature of certain physical parameters of the different collection locations of the samples that were the subject of these studies. However, the samples that were the subject of this study are less hydrated than the leaves of Pteridium aquilinum studied by Mananga et al. and which had obtained a water content of 91.72% [8]. The leaves of Moringa oleifera studied in 2011 in Burkina Faso had a water content of 73.9% [9]. This value is lower than the values obtained on the leaves of A. hypogaea (80.93±1.83%) and C. esculenta (84.89±0.57%) but lower than the value obtained on the leaves of C. cajan (68.13±0.46%) of this present study.

Table 1. Biochemical Composition and Nutritional Value of the Different Samples

The protein content of peanut leaves is low (on average 1.83%). This value, however, is very high compared to C. esculenta leaves but very low compared to C. cajan leaves. This allows us to conclude that A. hypogaea and C. esculenta leaves do not constitute fodder, with a protein content approaching 20%. The protein content of C. cajan leaves, on the other hand, is a quality fodder.

Matoumouene Goma et al., while characterizing Gnetum africanum leaves in Congo Brazzaville, found very high values (16.61%) [5]. This value is very high compared to the vegetables studied in this study, except for C. cajan, whose average protein content is 23.00±0.33%.

Coulibaly et al., working on Moringa oleifera leaves in the Bamako District of Mali, found a protein content of 22.2±3.00% [10]. This value is very high compared to the leaves of A. hypogaea and C. esculenta studied, but it is slightly low compared to the leaves of C. cajan, which were the subject of this study. Nimeza et al., who conducted a study on basella leaves from Burkina Faso, found a protein content of 1.9% [11]. This value is higher than the values found in this study. KABORE, from November 2009 to May 2010, conducted a study that showed that basella leaves contain protein levels of 1.8%. This value is also high compared to the taro leaves that were the subject of this study [12].

Adjantin et al., by characterizing the leaves of Gbolo (Crassocephalum crepidioides, Crassocephalum rubens) from Benin, found an average protein content of 27.13±0.01%. This value is higher than all the values found in all the leaves in this study [6]. Yao et al., working on some leaves consumed in Daloa, Ivory Coast, obtained protein contents ranging from 1.82 ± 0.12 to 5.22 ± 0.18% [8]. These values are lower than the protein content of C. cajan and much higher than the protein content of C. esculenta in this present study but take into account the value found in the leaves of A. hypogaea. A similar study conducted in Congo [8], gave the following results in proteins: Ferns (Pteridium aquilinum): 0.61%; Peanuts (Arachis hypogaea L.): 0.33% and Taros (Colocasia esculenta L.) Schott: 0.56%. The results of this study confirm that peanut and taro leaves are not good sources of protein although the values obtained in the recent study are higher [8]. The Moringa oleifera leaves studied in Burkina Faso had a protein content of 11.90% [9]. These leaves are therefore richer in protein than the leaves of A. hypogaea (1.83±0.08%) and C. esculenta (0.88±0.01%) but less rich than the leaves of C. cajan (23.00±0.33%) which were the subject of this study.

The Myrianthus arboreus leaves yielded a protein content of 57.02% [13]. This value is very high compared to the leaves of C. cajan, C. esculenta, and A. hypogaea, which were the subject of this study. Myrianthus arboreus leaves are higher in protein than C. cajan leaves. Lepengue et al., working on the leaves of wild pepper (Piper guineensis) from the forests of Gabon, found an average protein content of 26.04% [14]. This value is higher than any of the values found in the leaves studied in this study.

The lipid contents of the leaves studied were 0.38±0.13% for C. cajan, 1.32±0.07% for C. esculenta and 1.46±0.12% for A. hypogaea. These results show that the leaves studied are very low in lipids. However, A. hypogaea leaves are richer in lipids than C. esculenta leaves, which are richer in lipids than C. cajan leaves.

Windépagnagdé Yaméogo et al. in Burkina Faso had a lipid content of 1.10% [9]. These leaves are therefore less rich in lipids than A. hypogaea leaves (1.46±0.12%) and C. esculenta leaves (1.32±0.07%) but richer than C. cajan leaves (0.38±0.13%), which were the subject of this study.

Gbolo leaves (Crassocephalum crepidioides and Crassocephalum rubens) consumed in Benin are richer in lipids than the leaves that were the subject of this study with contents ranging from 2.75±0.01% for Crassocephalum rubens to 3.45±0.00% Crassocephalum crepidioides [6]. Kossiwa et al., working on taro leaves (Xanthosoma sagittifolium) in Togo had obtained an average lipid content of 0.55 ± 0.08% [15]. This value is higher than that of the leaves of C. cajan studied but very low compared to the leaves of C. esculenta and A. hypogaea that were the subject of this study. Yao et al., by characterizing some of the most consumed leafy vegetables in the city of Daloa (Centre-West, Ivory Coast) found lipid contents ranging from 0.29 ± 0.02 to 0.69 ± 0.04% [7]. These leafy vegetables have very low lipid contents compared to the leaves that were the subject of the present study. Mananga et al., by characterizing ferns (Pteridium aquilinum), peanuts (Arachis hypogea L.) and taros (Colocasia esculenta (L.) Schott found the following average lipid contents: 9.45% for Pteridium aquilinum, 16.21% for Arachis hypogaea and 4.46% for Colocasia esculenta [8]. These leafy vegetables are richer in lipids than the leaves of C. cajan, A. hypogaea and C. esculenta which were the subject of this study. This value is very high compared to the values obtained in this present study. We can thus say that the leaves of Pteridium aquilinum are richer in lipids than the leaves of C. cajan, C. esculenta and A. hypogaea which were the subject of this study. These leaves studied are also less rich in lipids compared to the leaves of Gnetum africanum [5] and which had obtained an average content of 7.34%.

The ash contents of the leaves studied are as follows: 0.62±0.00% for A. hypogaea; 2.16±0.02% for C. cajan and 1.32±0.07% for C. esculenta. It appears from these results that the leaves of C. cajan are richer in ash than the leaves of C. esculenta and the latter are richer in ash than the leaves of A. hypogaea. The leaves of Gbolo (Crassocephalum crepidioides and Crassocephalum rubens) studied in Benin have ash contents ranging from 19.02±0.01% to 19.76±0.05% [6]. These leaves are very rich in ash compared to the leaves studied in this present study. We can therefore conclude that Gbolo leaves are very rich in minerals compared to the leaves studied.

The leaves studied are also less rich in ash than the Gnetum afrcanum leaves [5]. Taro (Xanthosoma sagittifolium) leaves, found an ash content of 1.07 ± 0.00% [15]. This content is low compared to that of C. cajan leaves (2.16±0.02%) and C. esculenta leaves (1.32±0.07%) but high compared to A. hypogaea leaves (0.62±0.00%). Yao et al., working on some of the most consumed leafy vegetables in the town of Daloa in Ivory Coast, found ash contents ranging from 0.79 ± 0.01 to 0.95 ± 0.01% [7]. The leafy vegetables studied in Ivory Coast have ash contents higher than those of A. hypogaea but lower than those of C. cajan and C. esculenta in this present study. Lepengue et al., working on wild pepper (Piper guineense; Piperaceae) from the Gabonese forest, found a value of 3.4% crude ash [14]. This value is very high compared to the values found in this study in the leaves of A. hypogaea (0.62± 0.12%), C. cajan (2.16± 0.02%) and C. esculenta (1.32± 0.12%). The wild pepper leaves studied in Gabon are richer in minerals than the leaves that were the subject of the present study.

The leaves studied had carbohydrate contents of: 15.40±1.84% for A. hypogaea; 11.54±0.57% for C. esculenta; and 6.44±0.67% for C. cajan. Based on the results obtained in this study, we can conclude that the leaves studied are not a good source of carbohydrates. From these results, we conclude that A. hypogaea leaves are richer in carbohydrates than C. esculenta leaves, and C. esculenta leaves are richer in carbohydrates than C. cajan leaves. Gbolo leaves (Crassocephalum crepidioides and Crassocephalum rubens) from Benin, on the other hand, have carbohydrate contents ranging from 42.22 ± 0.04% for C. crepidioides to 43.11 ± 0.10% for C. rubens [6].

Gbolo leaves are therefore very rich in carbohydrates compared to the leaves studied in this study. The Gnetum africanum leaves have a carbohydrate content of 17.95% [5]. This content is also higher than the contents of the leaves studied in this study. Kossiwa et al., working on taro leaves from Togo, obtained a carbohydrate content of 11.05 ± 0.365% [15]. This value is essentially identical to the carbohydrate content of C. esculenta in this study, but it is lower than that of A. hypogaea and higher than the value obtained in the leaves of C. cajan in this current study. Yao et al., working on some of the most commonly consumed leafy vegetables in the town of Daloa in Côte d'Ivoire, found carbohydrate contents ranging from 71.26 ± 0.25 to 90.85 ± 0.12% in these vegetables (taro, spinach, potato, and cassava) [7].

The leafy vegetables studied in Côte d'Ivoire are richer in carbohydrates than the leaves that were the subject of this study. Kouame et al., working on the leaves of Myrianthus arboreus (Ticliti), obtained a carbohydrate content of 1.04% [13]. This value is very low compared to the values found in the leaves of this current study. Thus, we say that the leaves of Myrianthus arboreus (Ticliti) are very low in carbohydrates compared to the leaves of A. hypogaea, C. cajan and C. esculenta which were the subject of this study.

Lepengue et al., working on wild pepper (Piper guineense; Piperaceae) from the Gabonese forest, found a carbohydrate content of 21.48% [14]. This value is very high compared to the values found in this study in the leaves of A. hypogaea (15.40±1.84%), C. cajan (6.44±0.67%), and C. esculenta (11.54±0.57%). The wild pepper leaves studied in Gabon are richer in carbohydrates than the leaves that were the subject of this study.

Windépagnagdé Yaméogo et al. in Burkina Faso had a carbohydrate content of 10.60% [9]. These leaves are therefore less rich in carbohydrates than the leaves of A. hypogaea (15.40±1.84%) and C. esculenta (11.54±0.57%) but richer than the leaves of C. cajan (6.44±0.67%) which were the subject of this study.

The energy values of the leaves which were the subject of this present study are: 61.55±2.43 Kcal/100 g for C. esculenta; 81.26±5.86 Kcal/100 g for A. hypogaea and 120.94±1.56 Kcal/100 g for C. cajan. It appears from this study that the leaves of C. cajan are more energetic than the leaves of A. hypogaea and the latter are more energetic than the leaves of C. esculenta. However, the leaves of Gnetum africanum studied in Congo are more energetic than all these previous leaves with an energy value of 204.28 Kcal/100g [5]. Adjatin et al. had found in the leaves of Crassocephalum Crepidioides and Crassocephalum rubens the energy values ranging from 302.91±0.56 Kcal/100g for Crassocephalum rubens to 308.45±0.28 Kcal/100g for Crassocephalum crepidioides [6]. All these values are very high compared to the leaves of A. hypogaea, C. esculenta and C. cajan which were the subject of the present study. Yao et al., working on some of the most consumed leafy vegetables in the town of Daloa in Ivory Coast, the following values were found: 349.69±2.65 Kcal/100 g for Taro leaves; 373.30±0.43 Kcal/100 g for Spinach leaves; 344.84±0.92 Kcal/100 g for Potato leaves and 311.75±0.52 Kcal/100 g for Cassava leaves [7].

Comparison of the ash contents of these three species shows that C. cajan leaves are richer in minerals than C. esculenta leaves and the latter are richer in minerals than A. hypogaea leaves. The minerals sought in this study are: Calcium, Magnesium, Sodium, Potassium, Iron, Manganese, Copper and Zinc. Among the minerals identified in A. hypogaea leaves, potassium is the most represented chemical element, followed by calcium, then magnesium, sodium, iron; the other elements are in trace form. However, in C. cajan leaves, the most represented chemical element is potassium, followed by magnesium, calcium, sodium, iron, manganese; the others are in trace form. On the other hand, in C. esculenta leaves, sodium is the most represented chemical element, followed by calcium, potassium and magnesium; the others are in trace form. From the above, we can say that C. cajan leaves are richer in calcium and magnesium, potassium, iron, and zinc than A. hypogaea leaves and the latter are richer than C. esculenta leaves. However, C. esculenta leaves are richer in sodium than C. cajan leaves, followed by A. hypogaea leaves. Manganese and copper exist in trace amounts in all the leaves that were the subject of this study.

Table 2. Results of the mineral dosage of the different samples

Adjatin et al., showed by working on the leaves of Gbolo (Crassocephalum Crepidioides and Crassocephalum rubens) in Benin that the most represented chemical elements in leaves are: Potassium (K) with values of 2291.86±0.11 for C. crepidioides and 4469.91±0.11 for C. rubens, followed by Calcium (Ca), with a value of Calcium (Ca) 1012±0.06 for C. crepidioides and 3845.88±0.20 for C. rubens and Sodium (Na) with a value of 2213.45±0.73 for C. crepidioides and 2129.04±0.01 for C. rubens and finally Magnesium (Mg) with a value of 336.46±0.35 for C. crepidioides and 434.13±0.10 for C. rubens [6]. We can thus conclude that the leaves of green plants are good sources of potassium, calcium, sodium and magnesium. Other minerals exist in small proportions. Kossiwa et al., working on freshly harvested Taro leaves, obtained high levels of potassium (468 mg/100g), calcium (107.09 mg/100g), magnesium (19.20 mg/100g) [15]. Windépagnagdé Yaméogo et al., working on Moringa oleifera leaves, found the following minerals in the center: Calcium with a content of 847.10mg/100g; Magnesium with a content of 151.30mg/100g; Potassium, with a content of 549.60 mg/100 g. Moringa oleifera leaves are richer in calcium, potassium, and magnesium than the leaves of C. cajan, C. esculenta, and A. hypogaea, [9] which were the subject of this study.

These results obtained by these different authors further demonstrate that these chemical elements are generally present in high levels in the leaves of green plants.

Based on the results presented in this table, we can say that Cajanus cajan leaves are a significant source of minerals and are therefore recommended for human and animal nutrition.

Based on the results presented in this table, we can say that Colocasia esculenta leaves are a good source of minerals and are therefore recommended for human nutrition.

Conclusion and Outlook

Based on this study, the results show that peanut leaves and taro leaves are not fodder plants. However, Nkassa leaves, in which we found a high protein content, are important fodder plants for human and animal consumption. However, the leaves studied are good sources of minerals, therefore essential for human and animal nutrition.

In the future, we plan to:

Conduct chemical screening of the different leaves to identify biomolecules useful in medicine and establish the profile of the amino acids present in these leaves;

Define the vitamin profile of the leaves studied; determine the nutritional profile of the leaves in the treatment of certain diseases such as sickle cell disease and anemia.

References

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