HPTLC/DESI-MS imaging is a relatively fast, versatile, and efficient technique for natural product analysis, since many more ions are observed than with the direct infusion ESI-MS. The MS/MS technique provided information about the component structures, revealing the presence of important bioactive components. The application of DESI-MS imaging may contribute to the improvement identification and characterization of pharmacologically active compounds in phytochemistry.

The crude ethanolic extract from aerial parts of Pothomorphe umbellata L. (Piperaceae) and fractions obtained by partitions sequentially among water-methanol, methylene chloride, and ethyl acetate, as well as the major constituent, 4-nerolidylcatechol, were, respectively, evaluated and evidenced for antioxidant and cytotoxic effects through fluorometric microplate and microculture tetrazolium assays in HL-60 cells. The crude ethanolic extract demonstrated the preeminent antioxidant activity (IC50 = 1.2 μg/mL) against exogenous cytoplasmic reactive oxygen species, followed by the water-methanolic (IC50 = 4.5 μg/mL), methylene chloride (IC50 = 5.9 μg/mL), ethyl acetate (IC50 = 8.0 μg/mL), 4-nerolidylcatechol (IC50 = 8.6 μg/mL), and the sterol fractions (IC50 > 12.5 μg/mL). Vitamin C, the positive control used in this assay, presented IC50 value equivalent to 1.7 μg/mL. 4-Nerolidylcatechol (IC50 = 0.4 μg/mL) and methylene chloride fraction (IC50 = 2.3 μg/mL) presented considerable cytotoxicity probably because of the presence of an o-quinone, an auto-oxidation by product of the catechol. Polar compounds, present in the ethanol extract, appear to increase the solubility and stability of the major active constituent, acting synergistically with 4-nerolidylcatechol, improving its pharmacokinetic parameters and increasing significantly its antioxidant activity which, in turn, suggests that the aqueous-ethanolic extract, used in folklore medicine, is safe and effective.

Presently, natural products, such as Piper umbellata L. (Piperaceae), have been evaluated as sources of antimicrobial agents with efficacies against microorganisms. The in vitro antimicrobial activity was performed by broth micro-dilution susceptibility assay, according to the protocols of the National Committee for Clinical Laboratory Standards, and described the antibacterial and antifungal activities of crude ethanolic extract and fractions obtained by partitions sequentially among water-methanol, methylene chloride and ethyl acetate, as well as the major constituent, 4-nerolidylcatechol from the aerial parts of P. umbellata L. Amphotericin B and ciprofloxacin were used as controls. Among the microorganism cultures, hydromethanol fraction demonstrated the pre-eminent antifungal activity. 4-Nerolidylcathecol was the only tested plant component that exhibited activity against all the selected microorganisms, suggesting its great potential as a source for the development of new drugs. In order to estimate the antimalarial activity of P. umbellata L., a micro-dilution method protocol, parasite lactate dehydrogenase assay, with a Plasmodium falciparum Sierra Leone (D6) clone was utilised. The antimalarial agent artemisinin was used as control. 4-Nerolidylcathecol exhibited the best antimalarial activity; however, it was not significant when compared with control. These in vitro results do not justify the use of P. umbellata L. in malaria patients. However, there is a possibility of 4-nerolidylcathecol, after biotransformation, exhibiting a significant antimalarial activity in in vivo assays. However, 4-nerolidylcathecol demonstrated to possess a broad antimicrobial activity which is, in fact, a promising source for the development of new therapeutic agents.

Currently, natural products have been evaluated as sources of antimicrobial agents. Considering the increasing use of pomegranate, it has become important to establish a correlation between the phytocompounds and the antimicrobial properties of the crude extract used in Brazilian folklore medicine. The compositional analysis revealed the presence of classes of secondary metabolites of pharmaceutical interest, among them, tannins, flavonoids and phenolic compounds. The in vitro study was performed by broth micro-dilution susceptibility assay according to the protocols of the National Committee for Clinical Laboratory Standards and described the antibacterial and antifungal activities of the extract. The preeminent antimicrobial activities were recorded against Staphylococcus aureus and Staphylococcus epidermidis. In order to estimate the ex vivo antimicrobial activity of the extract, serum and granulomatous tissues were separately submitted to microbiological assay. The crude extract did not present any inhibition zone. Thus, it is possible to suggest that after the oral ingestion of the extract, bacteria present in the gastrointestinal tract of the animal, hydrolyze phytocompounds, which present antimicrobial potential in in vitro models but do not present sufficient serum and tissue concentrations to exert this activity in ex vivo and presumably in in vivo models.