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A laboratory experiment was developed to introduce undergraduate chemistry students to the chemical characterization of agroindustrial waste extracts by gas chromatography–mass spectrometry (GC–MS). The students prepared hexane and dichloromethane extracts from black pepper (Piper nigrum L.) waste. GC–MS analysis revealed the possible presence of sesquiterpenes and piperine, compounds commonly found in P. nigrum fruits. During postlab discussion, the students were encouraged to search for information about the biological properties of the putatively identified compounds. Most students found that piperine shows larvicidal activity. Thus, an experiment was conducted by a postgraduate research group to investigate the larvicidal potential of P. nigrum waste extracts. From the results, the students concluded that the hexane extract had higher larvicidal activity than the dichloromethane extract. We also provided students with the opportunity to identify piperine using (+)-APCI FT-ICR MS spectra. The proposed experiment helped students to learn and practice GC–MS and stimulated them to search the scientific literature for solutions to environmental problems.

Flowers from Dendranthema x grandiflorum (Ramat.) Kitam. are grown in Brazil for floristic trade, and residues from different cultivars are generated, containing flowers, leaves and stems. These residues can be used to produce larvicidal products. To confirm this hypothesis, 27 dichloromethane extracts were produced from Dendranthema x grandiflorum agricultural residues. All were analyzed by GC–MS and FT-ICR MS with two different ionization sources, APCI and ESI. The spectra and chromatograms were converted to matrices, which were used as input for PCA analyses. Simultaneously, the extracts at concentrations of 5 and 15 ppm were submitted to larvicidal assays on Aedes aegypti larvae, the etiological agent of dengue, chikungunya and zika diseases. High larvicidal activity (larvae mortality > 80%) was found for 14 samples, medium larvicidal activity (70% > larvae mortality > 40%) for 4 samples and low larvicidal activity (larvae mortality

This study aimed to investigate the accumulation of phthalates in the leaf epicuticular wax of Avicennia schaueriana and Rhizophora mangle. Leaves were collected from plants situated in three mangr...

The chemical composition and biological properties of citronella essential oil were modified by enzymatic esterification reaction of the major monoterpenic alcohols with cinnamic acid. The almost complete conversion of geraniol and citronellol present in the citronella (Cymbopogon winterianus) essential oil, into geranyl (99%) and citronellyl (98%) cinnamates was obtained after 48 hours of reaction using a molar ratio of 3:1 (cinnamic acid/alcohol), lipase concentration (Novozym 435) of 15% (w/w) and 70 °C. The esterified oil showed higher antimicrobial activity against Staphylococcus aureus bacteria resistant to oxacillin and penicillin and also greater larvicidal activity against Aedes aegypti larvae compared to unesterified oil. The results concerning the evaluation of toxicity against Artemia salina and cytotoxicity against monkey kidney epithelial cells also showed the superiority of the esterified oil.

This work aimed to investigate the main components of methanol fractions (MFSC and MFSCf) from Saccharum officinarum L. juice and their in vivo antinociceptive potential. After LC-ESI-MS and ESI-MS...

Saccharum officinarum L., Poaceae (sugarcane), occurs in tropical and subtropical areas of the planet, and Brazil stands out as the largest producer of sugar and ethanol from sugarcane. In addition, it is rich in phenolic substances, which have antioxidant potential, generating interest in its use in the cosmetic area. The objective of this work was to develop and characterize an emulsion and a nanoemulsion containing S. officinarum fraction. S. officinarum fraction was analyzed through liquid chromatography/electrospray ionization tandem mass spectroscopy (LC-ESI-MS) analysis and in vitro cytotoxicity. The formulations were developed with 10% Tween™ 80, 8% diethylamino hydroxybenzoylhexylbenzoate, 10% octylmethoxycinnamate, 0.3% conserv™, 1% aristoflex™ AVC, 0.4% of S. officinarum fraction, and distilled water. The emulsion was developed by the fusion-emulsification method and nanoemulsion by processing on the Hielscher UP100H Ultrasound for 5 min. The macroscopic aspects, pH, viscosity, mean droplet size, and in vitro FPS were analyzed. Through LC-ESI-MS analysis, it was possible to verify the presence of phenolic substances in the composition of methanol fraction from sugarcane juice and the IC50 estimated was 21.08 ± 6.43 mg/ml. All formulations presented pH around 5. The emulsion, emulsion with S. officinarum fraction, nanoemulsion, and nanoemulsion with S. officinarum fraction showed a size of 1.68 ± 0.12 μm, 0.58 ± 0.08 μm, 222 ± 1.58 nm, and 195.0 ± 0.53 nm, respectively. The in vitro sun protection factor of the emulsion, emulsion with S. officinarum fraction, nanoemulsion, and nanoemulsion with S. officinarum fraction was 20 ± 5, 30 ± 3, 24 ± 2, and 35 ± 5.6, respectively. The UVA/UVB ratio of all formulations was moderate and presented λc of 370 nm, which is considered a broad-spectrum product. Substances with photoprotective potential can be found in tailings from the sugarcane industry, suggesting that it can be converted into raw materials or innovative cosmetic products.

This study aimed to investigate the leaf epicuticular wax and the presence of heavy metals in leaves of Avicennia shaueriana, a halophyte found in Brazilian mangroves. We evaluated plants collected in mangroves located around Sepetiba Bay, Rio de Janeiro State. Heavy metals were analyzed by energy dispersive X-ray spectroscopy (EDS or EDX) and inductively coupled plasma optical emission spectrometry (ICP-OES). Chemical analysis of epicuticular wax was made by gas chromatography-mass spectrometry (GC-MS). We also evaluated the micromorphology of leaf surface using scanning electronic and light microscopy. The leaves from each mangrove presented alterations in wax layer. Fagarasterol (lupeol) in high quantity was the main triterpene identified in the leaf wax from plants collected in all mangroves: Coroa Grande (76.43%), Pedra de Guaratiba (38.91%), and Marambaia (62.56%). Al, Fe, Mn, and Zn were the main heavy metals detected in leaves from the three mangroves by ICP-OES. Thus, we show that that plants able to survive in the mangrove swamp can adapt to the exposure of heavy metals, accumulate them in their leaves, and be used in coastal area recovery projects as a phytoremediator.

Residues of the chrysanthemum agroindustry from different cultivars of Dendranthema x grandiflorum are sold in the Vitoria (Espirito Santo State, Brazil) marketplaces. Because of the large of varieties of this hybrid species, this study aimed to confirm the chemical similarity of the residual material collected in one year at the commercial places in neighborhoods of the city (Vitoria) for using it as an homogenous raw material to prepare larvicidal products. Dichloromethane and methanol extracts were produced from 27 samples. Medium infrared (MIR) spectra were obtained in triplicate for the 54 extracts. MIR data were analyzed by principal components analysis (PCA), which divided the samples into two groups (GA1 and GA2) for dichloromethane extracts and into four groups (GB1, GB2, GB3 and GB4) for methanol extracts. The methanol extracts, we could see clear separation among the groups based on their classes of substances. The dichloromethane ones, it was possible to identify separation between GA1 and GA2 by classes of triterpene esters and diacylglycerols based on their mass peak intensities. Mixtures obtained from dichloromethane extracts (FA) and methanol extracts (FB) were assayed on Aedes aegypti larvae at the concentration 15 ppm. FB mixtures no larval mortality was observed, but FA mixtures were 100% active, possibly by the presence of fatty acids, triterpenes, steroids and alkamides in the samples of this group. These results show that residues of different varieties of the hybrid Dendranthema x grandiflorum generate chemically similar extracts, particularly for the lipophilic ones (FA), which can be used as a homogeneous raw material to obtain biologically active products, notably larvicides products.

Utilization of marine algae has increased considerably over the past decades, since biodiversity within brown, red and green marine algae offers possibilities of finding a variety of bioactive compounds. Marine algae are rich sources of dietary fibre. The remarkable positive effects of seaweed dietary fibre on human body are related to their prebiotic activity over the gastrointestinal tract (GIT) microbiota. However, dietary modulation of microorganisms present in GIT can be influenced by different factors such as type and source of the dietary fibre, their molecular weight, type of extraction and purification methods employed, composition and modification of polysaccharide and oligosaccharide. This review will demonstrate evidence that polysaccharides and oligosaccharides from marine algae can be used as prebiotics, emphasizing their use in human health, their application as food and other possible applications. Furthermore, an important approach of microbial enzymes employment during extraction, modification or production of those prebiotics is highlighted.

Glycosylated flavonoids, caffeoylquinic acid and 3,5-dicaffeoylquinic acid have been identified in the ethyl acetate partition from the crude ethanol extract of Tocoyena bullata (Rubiaceae) leaves. The fraction containing the mixture of flavonol rutin and a tetraglycosylated flavonoid showed 89.2% inhibition and the mixture of isoquercitrin and 3,5-dicaffeoylquinic acid showed 88.5% inhibition of mast cell degranulation. These results demonstrated that the tetraglycosylated flavonoid, rutin, isoquercitrin and 3,5-dicaffeioylquinic acid were the most promising phenolics for inhibition of mast cell degranulation. For the first time the identification of phenolic constituents and their correlation with inhibitory effect on mast cell degranulation were reported in this work

The specie Ocotea notata (Nees & Mart). Mez is a tree with 5 meters high, that can be found in restinga regions in the Brazilian coast. This study describes a phytochemical investigation, total phenolic content and the antioxidant activity of extracts and fractions by DPPH and ORAC. Phenolic content revealed equivalent concentration between evaluated samples, similar to found in the leave extract (66.4 mEq GA/g). By DPPH, extracts and fractions showed effective concentration (EC50) lower than the standards Ginkgo biloba 761® (23.60 ± 0.64 µg/ml) and quercetin (6.06 ± 0, 92 µg/mL); for the ORAC method, ethyl acetate partition showed a value of 2.06 mmol Trolox equivalent g−1 better than obtained in Ginkgo biloba (1.03 ± 0.25 mmol.Trolox equivalent g−1. The butanol partition (0.52 mmol.Trolox equivalent g−1) and the aqueous residue (0.74 mmol Trolox equivalent g−1) have a lesser ORAC potential than ethyl acetate partition. The butanolic partition, investigated by LC-DAD-MS/MS and QTOF-MS, revealed six major compounds: miquelianin (1), isoquercitrin (2), quercitrin (3), kaempferol-3-O-pentose (4), afzelin (5) and isorhamnetin-glucuronide (6).

Peanut (Arachis hypogaea L.) is the fourth most consumed oleaginous plant in the world, producing seeds with high contents of lipids, proteins, vitamins, and carbohydrates. Biological activities of different extracts of this species have already been evaluated by many researchers, including antioxidant, antitumoral, and antibacterial. In this work, the allelopathic activity of extracts from different Brazilian peanut cultivars against lettuce (Lactuca sativa) and two weed plants (Commelina benghalensis and Ipomoea nil) was studied. Aerial parts, roots, seeds, and seed coats were used for the preparation of crude extracts. Seed extract partitioning was performed with n-hexane, dichloromethane, ethyl acetate, n-butanol, and aqueous residue. Germination and growth of hypocotyls and rootlets were evaluated after one and five days of incubation with plant extracts, respectively. Crude seed extract and its dichloromethanic partition displayed highest allelopathic activity. These results contribute for the study of new potential natural herbicides.

Ethanol extracts obtained from Schinus terebinthifolius Raddi fruits and leaves were active against Escherichia coli with MIC of 78 μg mL−1 for both extracts. Phytochemical analyses revealed a major presence of phenolic acids, tannins, fatty acids and acid triterpenes in the leaves and phenolic acids, fatty acids, acid triterpenes and biflavonoids in the fruits. Major compounds isolated from the plant, such as the acid triterpene schinol, the phenolic acid derivative ethyl gallate and the biflavonoids agathisflavone and tetrahydroamentoflavone, showed very little activity against E. coli. Bioautography of the ethanol extracts on silica gel plate showed inhibition zones for E. coli. They were removed from the plate and the compounds identified as a mixture of myristic, pentadecanoic, palmitic, heptadecanoic, stearic, nonadecanoic, eicosanoic, heneicosanoic and behenic fatty acids.

In hybrid cultivated form, Dendranthema grandiflorum (Ramat.) Kitam., Asteraceae, flowers (Chrysanthemum morifolium Ramat.) were utilized in the production of extracts, which were analyzed for larvicidal activity against Aedes aegypti third instar larvae. Methanol and dichloromethane extracts showed LC50 values of 5.02 and 5.93 ppm, respectively. Using GC–MS, phytochemical analyses of the dichloromethane extract showed the presence of triterpenoids and fatty acids, while flavonoids and caffeoylquinic acids were shown to occur in the methanol extract by ESI Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (ESI-FT-ICR-MS). Triterpenoids and fatty acids are well known insecticidal compounds. From this study, it can be concluded that D. grandiflorum grown for floriculture, as an agribusiness, can have additional applications as raw material for the production of insecticidal products. Keywords: Aedes aegypti, Caffeoylquinic acids, Agribusiness, Fatty acids, Larvicidal activity, Triterpenoids