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Given the necessity to find new alternatives as a biostimulant to improve plant growth, Moringa Leaf Extract (MLE) has been noticed by the scientific community for being a low-cost and natural product. Several studies have revealed the positive effects of MLE to enhance seed germination, seedling growth, photosynthetic pigments, antioxidant system, yield, and also confer resistance to a variety of abiotic stresses, such as drought, salinity, adverse temperatures, and heavy metals. However, we still require to investigate deeply the MLE composition and the different forms available to apply it. Thus, to integrate the current knowledge, this review insight of new approaches to the types of application, concentration utilized, and gathered different types of methodologies to obtain the MLE. In addition, the positive results of MLE to reduce the effects caused by abiotic stresses were discussed. Future studies should focus on identifying new varieties of Moringa to improve the quality of MLE and explore studies of MLE application not only in crop species but also forest species.

Hancornia speciosa has bioactive molecules such as phenolic compounds which exhibit antioxidant and antimicrobial properties. Nevertheless, the separation of these substances from a medicinal plant can be different according to the extraction process and solvent used. Thus, the present study aimed was to separate phenolic compounds from Hancornia speciosa leaves in three steps by using a sequential pressurized liquid extraction and evaluated their antioxidant and antibacterial activity. Results showed that the temperature increase from 25 to 60° C provides a significative enhancement in the extraction yield. The raw ethanol extract (39.0 ± 0.2%) showed the highest overall extraction yield. However, fractionated ethanol extract (FEE) at 60 °C exhibited the highest amount of total phenolic compounds (347.0 ± 4.12 mg/g extract). Fractionated ethyl acetate extract (FAE) at 60 °C presented improved quantity of total flavonoids (230.4 ± 3.5 mg/g extract) and rutin content (16.6 ± 0.3 mg/mL extract). The antioxidant activity results for IC50 of DPPH indicated that FEE (3.8 ± 0.1 µg/mL) was the best free radical scavenger. FAE and FEE were able to inhibit the growth of multidrug-resistant E. coli.

The essential oil from two Lantana species (Lantana lucida Schauer and Lantana salzmannii Schauer) were evaluated for their chemical composition by GC/MS. Results showed 17 predominant compounds for L. lucida, among which (E)-caryophyllene (19.0%) and α-humulene (33.0%) were the major components. L. salzmannii showed the presence of 58 compounds, the most abundant of which were (E)-caryophyllene (15.6%) and selin-11-en-4-ol (11.2%). Next, cluster analyses of the chemical composition of the volatile fraction of five Lantana species from our studies (Lantana radula, Lantana canescens, L. lucida, L. salzmannii and Lantana camara), as well as 10 Lantana species published in the literature (Lantana achyranthifolia, Lantana aculeata, Lantana balansae, Lantana hirta, Lantana involucrata, Lantana fucata, Lantana salviifolia, Lantana trifolia, Lantana velutina and Lantana xenica) were performed. Species fell into three main groups. A cluster analysis of (E)-caryophyllene content was also performed which resulted in the 15 Lantana species being segregated into four main groups. In addition, Inter-Simple Sequence Repeat (ISSR) was used to evaluate the genetic variation between five Lantana species collected from northeastern Brazil (L. radula, L. canescens, L. lucida, L. salzmannii and L. camara). Analysis showed a 36% similarity between, L. salzmanii and L. canescens, and a 48% similarity between L. lucida and L. canescens. Overall, results, indicate that it is possible to discriminate between groups of Lantana taxa based on both their chemical, composition and ISSR markers. In addition, this study provided further support for using (E)-caryophyllene as a chemical marker for species belonging to the Lantana genus.