Studies relating the consumption of food and their nutritional properties have a great contribution in the field of health. Intake of bioactive compounds, such as proteins, vitamins, minerals and other molecules present in foods can also present substances considered antinutritives or toxic, such as cyanide, polyphenols, nitrate, saponins, protease inhibitors and lectins. The tubers are rich in carbohydrates, proteins, vitamins, organic acids, anthocyanins, phytosterols, glycolipids, antioxidants, besides presenting low lipid content. Experimental analyzes of dioscorine, the main protein present in several varieties of yams (Dioscorea spp.) has been performed over the years, demonstrating several biological activities. The present study aims to isolate the protein fraction dioscorine present in tubers of Dioscorea cayennensis and to perform its phytochemical characterization by determining the presence of secondary compounds. The tubers underwent the process of separating the mucilage and obtaining the ultrafine flour, the protein extraction was performed in buffer solution: Tris HCl 0.05M pH 8.3, the total extract was submitted to protein precipitation with ammonium sulfate in the fraction 45-75% (F 45-75 ). The material underwent dialysis with molecular exclusion cutoff of 8 kDa, and lyophilization for sample concentration. Phytochemical determination was performed using specific techniques such as: saponins (foam-stirring test); tannins (reaction with ferric chloride/lead acetate/gelatin); carbohydrates (Molisch test); starch (iodine test); anthocyanins, anthocyanidins and flavonoids (pH variation test/heating); catechins (reaction with hydrochloric acid/heating), flavonols and xanthones (reaction with granulated magnesium/hydrochloric acid/heating). The chemical compounds identified in the total extract were: tannins, SciForum carbohydrates, saponins, flavones, flavonols and xanthones, the protein fraction did not show any phytochemical compound. Therefore, the isolated protein fraction of tubers of D. cayennensis showed no influence of secondary metabolites on their biological activities, being a target for the synthesis of natural products, considering their biotechnological and pharmaceutical importance.

Moringa oleifera Lam. is a plant native from India, but its distribution extends to all continents. Its leaves, flowers, pods and seeds are commonly used for food, mainly in Africa, due to its high nutritional value. With regard to medicine, M. oleifera demonstrates immeasurable potential in view of the various biological activities which are reported from its secondary compounds, such as alkaloids, tannins, flavonols, steroids, saponins, coumarins, quinones, resins, lectins among others. Based on this assumption, this review aims to expose the potential of Moringa oleifera in the period 2016-2018, in the use of its compounds for the synthesis of natural products due to its diverse biological activities. The results showed that the several parts of the plant may have different biological activities. The seeds have antibacterial activity with dental importance; activity in the prevention and deceleration of the amyotrophic lateral sclerosis disease (ALS); anti-hypertrophic and anti-fibrotic effect, being beneficial for cardiac structure and function in hypertensive mice; anticancer activity; anti-inflammatory; and protection of neural cells. For the leaves were reported Antitumor activities; therapeutic efficacy against neurotoxicity; for insulin expression and decrease in the degree of insulitis; antimicrobial activity; reduction of myocardial damage and oxidative stress; treatment in atopic dermatitis; gastroprotective activity and improvement of mucus; hypocholesterolemic effect; and ability to prevent chromatolysis, distortion of cerebellar cortical cells and neurobehavioral deficit. For the other parts of the plant similar activities are described, however in less quantity. Thus, Moringa oleifera presents a new perspective on the synthesis of natural products, considering the range of biological activities described for a species, as well as the ease of obtaining and using its compounds.

Fabaceae presents 145 subclades and 737 genera. Among them, the genus Sesbania, with about of 500 species, such as Sesbania virgata, whose seeds present high protein content. The present study aimed to characterize phytochemically, to evaluate the protein content and to bioprospect lectins and trypsin inhibitors in the protein extract of Sesbania virgata seeds. Seed meal was used to obtain Total Protein Extract (TPE) in Glycine-NaOH 0.1 mol.L-1 pH 9.0 NaCl 0.15 mol.L-1 (1:15, w/v). After 22 hours of magnetic stirring, the extract was centrifuged (7.076.3 x g, 30 min, and 4 °C) and the supernatant collected and named TPE. In this, it was determined the total protein content using the bovine serum albumin standard curve; bioprospecting lectins by hemagglutination assays in rabbit erythrocytes (CEUA/UFPB n° 178/2015), and trypsin inhibitors by enzyme assays using the enzyme bovine trypsin; and phytochemical characterization was given by different qualitative tests. TPE presented as protein content 7.13 mgP/mL and 106.96 mgP/gF; hemagglutination titers were 32 UH/mL, with 480 UH/gFa and 4.4887 UH/mgP; not precipitated trypsin inhibitors; and in phytochemical tests, reacted positively to saponins, catechins, flavones, flavonols, xanthones, anthocyanins, anthocyanidins SciForum and flavonoids, but reacted negatively to pyrogallic and catechin tannins, leucoantocyanidins, steroids and triterpenes. In other assays performed by our group (data not shown) in which an extract was obtained from buffer Glycine-HCl 0.1 mol.L-1 pH 2.6 NaCl 0.15 mol.L-1 , under the same conditions, it was found that this extraction method was not able of bioprospecting lectins, but favored the precipitation of protease inhibitors. It is understood, thus, that the extraction method influences the obtaining of TPE, the demarcation of considerable protein content and numerous phytochemical compounds, besides the hemagglutination assays suggest the presence of lectins. Together, all these constituents make TPE a versatile biotechnological tool, to check various biological activities.