Capsicum spp. pepper has great economic and social importance in agribusiness worldwide, mainly associated with its high performance in cookery as a spice. This study aimed at determining the chemical profile of the ethanolic extract from Capsicum chinense Jacq. (EECC) ripe fruits by liquid chromatography-mass spectrometry (LC-MS) and at evaluating its antioxidant activity by DPPH, ABTS and FRAP. Besides, biodegradable films were prepared by incorporating EECC into arrowroot biofilms. LC-MS identified 10 phenolic compounds, a fact that corroborates its high concentration of total phenolic compounds, i. e., 277.62 ± 12.06 mg gallic acid/100g crude extract. High antioxidant activity of EECC was expressed as IC 50 values for reagents DPPH (IC 50 = 18.04 µg/mL), ABTS (IC 50 = 25.33 µg/mL) and FRAP (IC 50 = 128.58 µg/mL). Biodegradable films incorporating different doses of EECC (250-1000 µL) were obtained by a casting technique. The higher the EECC concentration, the higher their thickness, color, variable moisture content and the lower their solubility. This study proposes a new use to the plant extract from C. chinense, a natural product that may be applied to the development of biofilms to coat food and retard its deterioration. In addition, antioxidant activity of this type of pepper is also shown.

Xylella fastidiosa is a plant-pathogenic bacterium that lives inside host xylem vessels, where it forms biofilm which is believed to be responsible for disrupting the passage of water and nutrients. Pectobacterium carotovorum is a Gram-negative plant-specific bacterium that causes not only soft rot in various plant hosts, but also blackleg in potato by plant cell wall degradation. Chagas disease, which is caused by Trypanosoma cruzi, has been commonly treated with nifurtimox and benzonidazole, two drugs that cause several side effects. As a result, the use of natural products for treating bacterial and neglected diseases has increased in recent years and plants have become a promising alternative to developing new medicines. Therefore, this study aimed to determine, for the first time, the chemical composition of essential oil from Psidium guajava flowers (PG-EO) and to evaluate its in vitro anti-Xylella fastidiosa, anti-Pectobacterium carotovorum, anti-Trypanosoma cruzi and cytotoxic activities. PG-EO was obtained by hydrodistillation in a Clevenger apparatus while its chemical composition was determined by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Major compounds identified in PG-EO were α-cadinol (37.8%), β-caryophyllene (12.2%), nerolidol (9.1%), α-selinene (8.8%), β-selinene (7.4%) and caryophyllene oxide (7.2%). Results showed that the PG-EO had strong trypanocidal activity against the trypomastigote forms of Trypanosoma cruzi (IC50 = 14.6 μg/mL), promising antibacterial activity against X. fastidiosa (MIC = 12.5 μg/mL) and P. carotovorum (MIC = 62.5 μg/mL), and moderate cytotoxicity against LLCMK2 adherent epithelial cells in the concentration range (CC50 = 250.5 μg/mL). In short, the PG-EO can be considered a new source of bioactive compounds for the development of pesticides and trypanocide drugs.

Eugenia species have been appreciated for their edible fruits and medicinal properties. This paper aims to investigate the chemical composition and in vitro antileishmanial, antifungal and antiproliferative activities of essential oil from aerial parts of Eugenia pyriformis (EP-EO). The oil showed strong antileishmanial activity against promastigote forms of Leishmania amazonensis (IC 50 = 2.16 µg/mL). It also exhibited high antifungal activity against Malassezia furfur (MIC = 30 µg/mL), which was determined by the broth microdilution method. Its antiproliferative activity was evaluated against the following cells: GM07429A (normal cell), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma) and M059J (human glioblastoma). Its major constituents, which were determined by GC-FID and GC-MS, were limonene (14.8%), nerolidol (11.0%), α-cadinol (10.3%), caryophyllene oxide (9.9%) and β-pinene (7.1%). These results showed, for the first time, the effectiveness of EP-EO as a natural product which has promising biological activities, a fact that enables its ethnopharmacological use.

Endodontic infections result from oral pathogenic bacteria which reach and infect dental pulp, as well as surrounding tissues, through cracks, unrepaired caries and failed caries restorations. This study aims to determine the chemical composition of essential oil from Psidium cattleianum leaves (PC-EO) and to assess its antibacterial activity against endodontic bacteria. Antibacterial activity of PC-EO was evaluated in terms of its minimum inhibitory concentration (MIC) values by the broth microdilution method on 96-well microplates. Bacteria Porphyromonas gingivalis (MIC = 20 µg/mL), Prevotella nigrescens (MIC = 62.5 µg/mL), Fusobacterium nucleatum (MIC = 12.5 µg/mL), Actinomyces naeslundii (MIC = 50 µg/mL), Bacteroides fragilis (MIC = 12.5 µg/mL), Aggregatibacter actinomycetemcomitans (MIC = 6.25 µg/mL) and HIGHLIGHTS  Viridiflorol, β-caryophyllene, 1,8-cineole and β-selinene were the major constituents found in PC-EO. Promising antibacterial activity of essential oil from Psidium cattleianum fresh leaves was evident, with MIC values below 100 µg/mL.  Seven bacteria of endodontic interest were used. PC-EO exhibited high anti-Aggregatibacter actinomycetemcomitans activity (MIC = 6.25 µg/mL). Chrystal, P.; et al.

Starch is a promising source of biopolymers and the incorporation of essential oils (EOs) into it can improve some biological properties of films. This study aimed at developing and characterizing barrier, biodegradability and optical properties of biopolymeric films made from arrowroot starch and at incorporating EOs from Piper aduncum leaves and inflorescences in order to analyze their antifungal activity against Rhizopus microsporus and Colletotrichum gloeosporioides. The casting method was used for developing arrowroot starch films and incorporating EOs into them. Resulting films exhibited satisfactory barrier properties, low water vapor permeability (WVP), transparency and good barrier property against UV-vis light, besides being 100% biodegradable. In addition, films enriched with EOs at 0.75% and 1.0% revealed promising antifungal activity. Results showed, for the first time, that arrowroot starch enriched with EOs from P. aduncum can potentially be used as an active film due to its excellent physicochemical properties and antimicrobial activity.

Propolis is a resinous substance collected and processed by Apis mellifera from parts of plants, buds and exudates. In Minas Gerais (MG) state, Brazil, green propolis is produced from the collection of resinous substance found in shoot apices of Baccharis dracunculifolia. This paper aims to investigate the chemical composition and in vitro antioxidant, anti-Helicobacter pylori, antimycobacterial and antiproliferative activities of essential oil (EO) from Brazilian green propolis (BGP-EO). The oil showed high antibacterial activity against H. pylori (MIC = 6.25 µg/mL), Mycobacterium avium (MIC = 62.5 µg/mL) and M. tuberculosis (MIC = 64 µg/mL). Its antioxidant activity was evaluated in vitro by both DPPH (IC50 = 23.48 µg/mL) and ABTS (IC50 = 32.18 µg/mL) methods. The antiproliferative activity in normal (GM07492A, lung fibroblasts) HIGHLIGHTS The chemical composition of propolis varies according to the region where it is produced. Production of green propolis in Minas Gerais state, Brazil, is related to the high amount of resin yielded by Baccharis dracunculifolia. Major compounds found in essential oil from Brazilian green propolis were carvacrol, acetophenone, spathulenol, (E)-nerolidol and β-caryophyllene. Brazilian green propolis showed high antibacterial, antioxidant and antiproliferative activities.

Brazil, the world's largest citros producer, yields around 19 million tons per year and exports most part of its production as orange juice. Essential oils (EOs) extracted from leaves, fruit and flowers of many species of the genus Citrus have been widely used as the result of their promising bioactivities. The fungus Rhizopus stolonifer (Ehrenb.) Vuill., an agent which causes soft rot in fruit, has been considered one of the main factors that cause postharvest diseases, thus, leading to major economic losses in agribusiness. This research aimed at evaluating the chemical composition and in vitro antifungal effect of EOs from two varieties of fresh Citrus sinensis (lima orange and bahia navel orange) peel on mycelial growth of R. stolonifer. EOs were obtained by hydrodistillation, which was carried out by a Clevenger-type apparatus, while their chemical composition was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Limonene was the major monoterpene identified in EOs from lima orange (95.2%) and bahia navel orange (93.2%) peel. EOs from lima orange and bahia navel orange inhibited 91.95% and 80.05% mycelial growth of R. stolonifer, respectively, at the highest dose under evaluation (100 µL). This study revealed the biotechnological potential of EOs extracted from fruit peel of two varieties of citros which may applied to biofilm preparation, so as to coat and preserve different types of fruit.

Numerous studies have investigated the chemical composition and biological activities of essential oils from different Citrus species fruit peel, leaves and flowers. This paper aims to investigate the chemical composition, larvicidal and antileishmanial activities of essential oil from Citrus reticulata fruit peel (CR-EO). CR-EO was obtained by hydrodistillation in a Clevenger-type apparatus and its chemical composition was analyzed by GC-MS and GC-FID. Limonene (85.7%), ɣ-terpinene (6.7%) and myrcene (2.1%) were identified as its major components. CR-EO showed high activity against promastigote forms of Leishmania amazonensis (IC50 = 8.23 µg/mL). CR-EO also exhibited high larvicidal activity against third instar Aedes aegypti larvae at a lethal concentration (LC50 = 58.35 µg/mL) and 100% mortality at 150 µg/mL. This study suggests, for the first time, the potential use of CR-EO against this important mosquito-borne viral disease caused by the genus Aedes.