Abstract: The phenolic extracts of jabuticaba skin flour (JSF) were characterized by HPLC, and evaluated for their modulating action upon phospholipases A2 and proteases of snake venom, aiming at their possible use in the treatment of the various diseases associated with the action of venom toxins. Two types of extracts were prepared from JSF: aqueous and methanolic. These extracts, evaluated at different ratios, (venom: extract, m/m), significantly inhibited the phospholipase activity induced by the venom of Bothrops moojeni and Crotalus durissus terrificus, except for Bothrops atrox venom. The greatest hemolysis inhibitory action was observed for the methanolic extract, when incubated with venoms of B. moojeni and C. durissus terrificus, with inhibitions between 21 and 100%. Thrombolysis induced by venoms of B. moojeni and C. durissus terrificus was inhibited by both extracts, ranging from 32 to 83% and 51 to 83% for the aqueous and methanolic extracts, respectively. Both extracts extended coagulation time, induced by the venoms of B. moojeni and Lachesis muta muta. Inhibitory actions are related to phenolic compounds, such as gallic, syringic and p-coumaric acids, besides catechin, epigallocatechin gallate, epicatechin; resveratrol and quercetin, present in the extracts of jabuticaba skin flour, confirming their potential for nutraceutical use.

ABSTRACT Leaves of Psidium guajava L. (guava) have been widely used in the popular way for prevention and treatment of various diseases. Thus, the objective of this study was to evaluate the inhibitory potential of leaves aqueous extract from three cultivars of P. guajava (Pedro Sato, Paluma and Século XXI) on α-amylase, α-glycosidase, lipase, and trypsin enzymes, in the presence or not of simulated gastric fluid and to determine the content of phenolic compounds by high performance liquid chromatography. All cultivars presented the same composition in phenolic compounds, but in different proportions. The compounds identified are gallic acid, epigallocatechin gallate, syringic acid, o-coumaric acid, resveratrol, quercetin, and catechin (which was the major compound in all the cultivars evaluated). In the absence of simulated gastric fluid, it was observed different inhibitions exercised by the leaves aqueous extracts from three cultivars of P. guajava on each enzyme. In presence of simulated gastric fluid, all cultivars showed increase in the inhibition of lipase and α-glycosidase, and decrease in inhibition of α-amylase and trypsin enzymes. These results indicate that P. guajava leaves aqueous extracts from all cultivars evaluated possess potential of use as an adjuvant in the treatment of obesity and other dyslipidemias.

ABSTRACT Adding value to fruit residues is of great interest, since they can be presented as a viable solution in search of new drugs for the treatment of obesity and related diseases, due to bioactive substances, especially phenolic compounds. Thus, the objective of this study was to prepare the methanol extract of acerola bagasse flour, in order to evaluate its potential as a source of inhibitors of the enzymes α-amylase, α-glucosidase, lipase and trypsin, and determine the content of phenolic compounds by high performance liquid chromatography. Enzymatic inhibition assays were conducted in the presence or absence of simulated gastric fluid. In the methanol extract of acerola bagasse flour, the following phenolic compounds were identified: gallic acid, syringic and p-coumaric acid, catechin, epigallocatechin gallate, epicatechin and quercetin; epicatechin was the major compound. In the absence of gastric fluid, simulated enzymes had a variable inhibition of the acerola bagasse flour extract, except for lipase, which was not inhibited. In the presence of simulated gastric fluid, there was an inhibition of 170.08 IEU (Inhibited Enzyme Unit in µmol min−1 g−1) for α-amylase and 69.29 IEU for α-glucosidase, indicating that this extract shows potential as an adjuvant in the treatment of obesity and other dyslipidemia.

Fall armyworm, Spodoptera frugiperda J.E. Smith, 1797 (Lepidoptera: Noctuidae) is the main pest of maize, besides attacking sorghum and cotton crops. The control of this pest has been accomplished mainly with the use of synthetic insecticides but, due to the growing concern about the environment and food quality, phenolic compounds have shown their potential for the biological control of this insect. Thus, the objective of the present study was to evaluate the efficiency of the extract of jabuticabeira, Myrciaria cauliflora [Mart.] O. Berg (Myrtaceae) fruit skin flour in the control of S. frugiperda. Skins of M. cauliflora Sabará genotype were dried at 45 °C in a forced air oven. In order to obtain the extract, 1.0 g flour was mixed with 10 mL acetone: water solution (7:3 v/v). Forty-eight-hour-old S. frugiperda caterpillars were placed in glass tubes with an artificial diet containing the extract at concentrations of 0, 250, 500, 1000, and 2000 mg L-1. The extract, in which the phenolic compounds gallic acid, gallocatechin, catechin, epicatechin, ellagic acid, and salicylic acid were identified at a concentration of 2000 mg L-1, in average, increased mortality rates by 150% in the larval stage, duration of larval stages by 60%, and pupal by 17%, and decreased amount of females by 55%. On the other hand, the extract at 1000 mg L-1 only increased duration of larval period by 24%. It was concluded that the extract is harmful to this insect, probably due to the presence of phenolic compounds.

No Brasil, a farinha de folhas de mandioca (FFM) vem sendo usada no combate à desnutrição, por ser fonte de vitaminas e minerais, além de ser um subproduto de ampla disponibilidade e baixo custo. Porém, a toxicidade, devido à presença de cianeto, pode restringir seu uso na alimentação humana. Determinaram-se os teores de cianeto nas folhas e nas FFM de cinco cultivares (Ouro do Vale, Maracanã, Mantiqueira IAC 24-2, IAC 289-70 e Mocotó), a fim de selecionar a cultivar com menores níveis desse antinutriente. Constatou-se que as cultivares apresentaram diferentes teores de cianeto e percentuais de perdas, destacando-se a IAC 289-70, com os níveis mais baixos e os maiores percentuais de perdas de cianeto. Portanto, antes de se indicar uma cultivar para a inclusão na dieta da população, faz-se necessário avaliar os teores de cianeto.

In Brazil, cassava leaves flour (CLF) has been used to combat undernourish, because it is a source of vitamins and minerals. Besides that, it is a sub-product of wide availability and low cost material. However, the toxicity, due to the presence of cyanide, can restrict its use for human feeding. The contents of cyanide in leaves and in CLF of five cultivars (Ouro do Vale, Maracanã, Mantiqueira IAC 24-2, IAC 289-70 and Mocotó), were determined, in order to select cultivars with smallest levels of these substance. It was verified that cultivars presented different levels of cyanide and percentile of losses, standing out the IAC 289-70 with the lowest levels and the largest losses of cyanide. Therefore, before indicating a cultivar for the inclusion in the population diet it is necessary to evaluate the contents of cyanide.