Several studies have demonstrated anti-carcinogenic and antitumor activity for many essential oils obtained from various plant species. They may be used in substitution to or in addition to conventional anti-cancer therapy. Although many studies report possible mechanisms of action for essential oils compounds, more studies are necessary in order to apply them safely and appropriately in cancer therapy.

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Disintegrins are non-enzymatic proteins that interfere on cell–cell interactions and signal transduction, contributing to the toxicity of snake venoms and play an essential role in envenomations. Most of their pharmacological and toxic effects are the result of the interaction of these molecules with cell surface ligands, which has been widely described and studied. These proteins may act on platelets, leading to hemorrhage, and may also induce apoptosis and cytotoxicity, which highlights a high pharmacological potential for the development of thrombolytic and antitumor agents. Additionally, these molecules interfere with the functions of integrins by altering various cellular processes such as migration, adhesion and proliferation. This review gathers information on functional characteristics of disintegrins isolated from snake venoms, emphasizing a comprehensive view of the possibility of direct use of these molecules in the development of new drugs, or even indirectly as structural models.

Dyslipidemias are associated with the incidence of cardiovascular diseases, obesity, diabetes, hypertension and hepatic steatosis, being the cause of morbidity and mortality. This study investigated the effects of lychee peel flour (PF) on serum levels of total cholesterol (TC), low-density lipoprotein (LDL-c), triacylglycerols (TAG) and various parameters related to obesity, in rats fed a hypercholesterolemic diet. Therefore, 20 male rats were used. In the first 21 days, the animals were fed a hypercholesterolemic diet, except for control group. In the following 21 days, their diets were modified, and they received a standard diet (Control); hypercholesterolemic (Hyper); hypercholesterolemic + 5% PF (PF5) and hypercholesterolemic + 10% PF (PF10). The results revealed that PF intake attenuated weight gain, reduced body mass index, glucose and the levels of TAG, TC, LDL-c, hepatic enzymes and leptin, besides the percentage of hepatic lipids, liver lipid peroxidation and frequency of severe steatosis. Histological studies of the aorta did not show the formation of the atheromatous plaque. These results reinforce its potential to reduce the risk of diseases associated with obesity.

Guava (Psidium guajava L.) is fruit with very short shelf life due to associated with the loss of firmness in the pulp and information on the activity of enzymes that degrade pectic substances, as well as the amount of pectin, is very contradictory and not clearly defined. This work showed that the firmness of the fruit decreased sharply on the first four days of ripening. The identified phenolic compounds had their content increased with fruit maturation. The addition of the enzymes cellulase and hemicellulase in the pectin extraction in fruits of Psidium guajava revealed higher contents of this polyssacaride that the ones reported in literature, highlighting pectin as the responsible for the firmness of these fruits at more adequate contents. β-D-glucosidase was identified as one of the responsible enzymes for the maturation of P. guajava fruits. Thus, studies about possible inhibitory effects of this enzyme in P. guajava fruits may reveal an important tool to reduce pectin release and early maturation of these fruits.Keywords: Psidium guajava; pectin; phenolic compounds; β-D-glucosidase; esterase.Practical Application: Guava is a highly perishable fruit and information on the activity of enzymes that degrade pectic substances and the amount of pectin, not are clearly defined. This work showed that the firmness of the Guava decreased with ripenig, that pectin is responsible for the firmness and that the content phenolic compounds increased with fruit maturation. β-D-glucosidase was identified as one of the responsible enzymes for the maturation, thus possible inhibitory effects of this enzyme may reduce pectin release and early maturation of these fruits. Braga et al.

The aim of this study was to quantify antioxidant substances and chlorophyll content, as well as to measure the antioxidant activity in cassava leaf flour (CLF) of different cultivars at several plant ages, in order to lead to a higher utilization of these leaves, and consequently to an enhancement of this agricultural by-product. The contents of antioxidant substances (vitamin C, polyphenols and β-carotene) were regarded as high and increased as the plants matured. The chlorophyll content decreased with plant maturity and presented a negative correlation with antioxidant substances, which indicates that the highest antioxidant levels are found when the plant presents low chlorophyll levels. CLF showed a high antioxidant activity when the lipid oxidation inhibition method (β-carotene/linoleic acid) was used, and moderate when the free radical capture method (ABTS) was used. The main contribution to the CLF antioxidant activity seems to be provided by vitamin C, which presented the best correlation with the ABTS test. Out of the ages studied, that of 14 months presented the highest antioxidant levels; Mocotó and Pão da China cultivars stood out the most.

Agro‐industrial wastes are promising sources of phytochemicals for the development of products to be used in health promotion and maintenance. In this study, extracts from acerola bagasse (AB) were characterized by HPLC, and evaluated according to its modulatory action on phospholipases A2 and proteases involved in processes such as inflammation and blood clotting. Snake venoms were used as biological tools once they have high functional and structural homology between their enzymes and human enzymes. Two types of extracts were prepared from AB: aqueous and methanolic. These extracts, evaluated at different proportions (venom:extract, w:w), significantly inhibited the phospholipase activity induced by the venoms of Bothrops moojeni, Bothrops atrox (11% to 31%), and Crotalus durissus terrificus (C. d. t.) (11% to 19%). The hemolytic activity induced by the venoms of B. moojeni and C. d. t. was better inhibited by the methanolic extract (inhibition between 23% and 48%). Thrombolysis induced by the venoms of B. moojeni and C. d. t. was inhibited by both extracts, with inhibition ranging from 13% to 63% for the aqueous extract, and from 12% to 92% for the methanolic one. Both extracts increased the time of coagulation induced by the venoms of B. moojeni and Lachesis muta muta in 26 and up to 68 s. These inhibitory actions were related to the following phenolic compounds present in the extract of AB: gallic acid, catechin, epigallocatechin gallate, epicatechin, syringic acid, p‐coumaric acid, and quercetin. Additional studies are needed to confirm their potential use for nutraceutical purposes. Practical Application Agro‐industrial wastes are promising sources of phytochemicals for the development of products that can be used by pharmaceutical, cosmetics, and food industries. Studies report the use of the acerola bagasse extract in health improvement. However, its toxic‐pharmacological characterization is still scarce. In this study, the extracts of acerola bagasse presented phenolic compounds that can modulate the activity of enzymes such as phospholipases A2 and proteases that act on the coagulant/anticoagulant and thrombotic/thrombolytic activities and the break of phospholipids, decreasing the inflammation and platelet aggregation. Although the in vivo effects of the extracts are not fully understood, this study shed light upon the possibilities of their usage.

A large number of natural compounds, such as phenolic compounds, have been scientifically evaluated in the search for enzyme inhibitors. The interactions between the phenolic compound p‐coumaric acid and the enzymes present in snake venoms (used as research tools) were evaluated in vitro and in silico. The p‐coumaric acid was able to inhibit 31% of the phospholipase activity induced by Bothrops alternatus venom, 27% of the hemolytic activity induced by B. moojeni, 62.5% of the thrombolytic activity induced by B. jararacussu, and approximately 27% of the activity thrombosis induced by Crotalus durissus terrificus. Previous incubation of p‐coumaric acid with the venoms of B. atrox and B. jararacussu increased the coagulation time by 2.18 and 2.16‐fold, respectively. The activity of serine proteases in B. atrox and B. jararacussu venoms was reduced by 60% and 66.34%, respectively. Computational chemistry analyses suggests the specific binding of p‐coumaric acid to the active site of proteases through hydrogen and hydrophobic interactions. The phenolic compound evaluated in this work has great potential in therapeutic use to both prevent and treat hemostatic alterations, because the venom proteins inhibited by the p‐coumaric acid have high homology with human proteins that have a fundamental role in several pathologies.