Lucia M. Conserva

Alkaloids and coumarins from Esenbeckia species

Abstract Investigation of two species of Esenbeckia, E. almawillia and E. grandiflora , has led to the isolation and identification of kokusaginine, maculine, maculosidine, flindersiamine, xanthotoxin, pimpinellin, 4-methoxy-1-methylquinolin-2-one, two new 2-arylquinolin-4-one alkaloids and two 3-(1′,1′-dimethylallyl)dihydrofurocoumarins derivatives. Structures of all compounds were elucidated by spectroscopic methods.

Antinociceptive and Anti-Inflammatory Effects of Octacosanol from the Leaves of Sabicea grisea var. grisea in Mice

Sabicea species are used in the Amazon for treatment of fever and malaria, which suggests that its chemical constituents may have some effect on pain and inflammation. Phytochemical analysis of the hexane fraction obtained from the crude ethanol extract from Sabicea grisea var. grisea Cham. & Schltdl (Rubiaceae), an endemic plant in Brazil, resulted in the isolation of octacosanol. This study investigated the antinociceptive and anti-inflammatory effects of the octacosanol in different experimental models. The crude ethanolic extract and hexane fraction obtained from the leaves of S. grisea produced an inhibition of acetic acid-induced pain. Moreover, octacosanol isolated from the hexane fraction produced a significant inhibition of pain response elicited by acetic acid. Pre-treatment with yohimbine, an alpha 2-adrenergic receptor antagonist, notably reversed the antinociceptive activity induced by octacosanol in the abdominal constriction test. Furthermore, mice treated with octacosanol did not exhibit any behavioral alteration during the hot plate and rota-rod tests, indicating non-participation of the supraspinal components in the modulation of pain by octacosanol with no motor abnormality. In the formalin test, octacosanol did not inhibit the licking time in first phase (neurogenic pain), but significantly inhibited the licking time in second phase (inflammatory pain) of mice. The anti-inflammatory effect of octacosanol was evaluated using carrageenan-induced pleurisy. The octacosanol significantly reduced the total leukocyte count and neutrophils influx, as well as TNF-α levels in the carrageenan-induced pleurisy. This study revealed that the mechanism responsible for the antinociceptive and anti-inflammatory effects of the octacosanol appears to be partly associated with an inhibition of alpha 2-adrenergic transmission and an inhibition of pathways dependent on pro-inflammatory cytokines. Finally, these results demonstrated that the octacosanol from the leaves of S. grisea possesses antinociceptive and anti-inflammatory activities, which could be of relevance for the pharmacological control of pain and inflammatory processes.

Borreria and Spermacoce species (Rubiaceae): A review of their ethnomedicinal properties, chemical constituents, and biological activities.

Borreira and Spermacoce are genera of Rubiaceae widespread in tropical and subtropical America, Africa, Asia, and Europe. Based on its fruits morphology they are considered by many authors to be distinct genera and most others, however, prefer to combine the two taxa under the generic name Spermacoce. Whereas the discussion is still unclear, in this work they were considered as synonyms. Some species of these genera play an important role in traditional medicine in Africa, Asia, Europe, and South America. Some of these uses include the treatment of malaria, diarrheal and other digestive problems, skin diseases, fever, hemorrhage, urinary and respiratory infections, headache, inflammation of eye, and gums. To date, more than 60 compounds have been reported from Borreria and Spermacoce species including alkaloids, iridoids, flavonoids, terpenoids, and other compounds. Studies have confirmed that extracts from Borreria and Spermacoce species as well as their isolated compounds possess diverse biological activities, including anti-inflammatory, antitumor, antimicrobial, larvicidal, antioxidant, gastrointestinal, anti-ulcer, and hepatoprotective, with alkaloids and iridoids as the major active principles. This paper briefly reviews the ethnomedicinal uses, phytochemistry, and biological activities of some isolated compounds and extracts of both genera.

Coumarin Derivatives from Esenbeckia grandiflora. and its Larvicidal Activity Against Aedes aegypti.

Abstract From a hexane fraction prepared from the roots of Esenbeckia grandiflora. Mart., effective against fourth instar larvae of Aedes aegypti. L. (LC50 108.23 ppm), eight coumarin derivatives [daphnetin 7-methyl-8-(3,3-dimethylallyl) ether, a mixture containing pimpinellin eight one of its photodimerization product, 5-senecioyl-xanthotoxin, 3-(1′,1′)-dimethylallylcolumbianetin, swietenocoumarin B, isopimpinellin, xanthotoxin, and 5-(1′-hydroxyisopentenyl)bergapten] were isolated in addition to sitosterol and sitostenone. The mixture containing pimpinellin and its photodimerization product was effective against fourth instar larvae (LC50 at 45.77 ppm), and a mixture of pimpinellin and swietenocoumarin B showed a LC50 value of 62.23 ppm. All isolated compounds were identified on the basis of the spectral data including 2D experiments. Furthermore, previously unreported spectral data for some compounds are given.

Larvicidal activities and chemical composition of essential oils from Piper klotzschianum (Kunth) C. DC. (Piperaceae)

BACKGROUND Volatile oils from fresh roots, stems, leaves and seeds of Piper klotzschianum (Piperaceae) were obtained by hydrodistillation and analysed by GC-FID and GC-MS. In total, 25 components, representing more than 95% of the examined oils, were identified. The essential oils were evaluated against Artemia salina Leach nauplii and fourth-instar Aedes aegypti larvae. RESULTS The major chemical constituents that were identified from various parts of this plant were 1-butyl-3,4-methylenedioxybenzene and 2,4,5-trimethoxy-1-propenylbenzene in the root, 1-butyl-3,4-methylenedioxybenzene in the stems and leaves and 1-butyl-3,4-methylenedioxybenzene, limonene and α-phellandrene in the seeds. The biological activities of these essential oils generally exhibited high toxicity against A. salina, with LC50 values that ranged from 7.06 to 15.43 µg mL(-1), and significant larvicidal activity against fourth-instar A. aegypti larvae was observed in the essential oils from the seeds (LC50 of 13.27 µg mL(-1)) and roots (LC50 of 10.0 µg mL(-1)) of the plant. CONCLUSION The present study indicates that both essential oil of P. klotzsdhianum and the isolate 1-butyl-3,4-methylenedioxybenzene are potential resources for A. aegypti larva control. This is the first report of the biological activities of the oil and isolated compound.

Terpenóides e avaliação do potencial antimalárico, larvicida, anti-radicalar e anticolinesterásico de Pouteria venosa (Sapotaceae)

This work describes the isolation of four triterpenes (taraxerol, ursolic acid, 3b,19a,23-trihydroxyurs-12-en-28-oic acid and 2a,3a,19a,23-tetrahydroxyurs-12-en-28-oic acid) and a phytosteroid (spinasterol), as well as a preliminary evaluation of antimalarial (NK-65 strains of Plasmodium berghei), larvicidal (4th instar of Aedes aegypti), anti-radicalar (2,2-diphenyl-1-pycryl-hydrazyl, DPPH) and anticholinesterase activities of Pouteria venosa (Mart.) Baehni extracts from leaves, stem barks and stems. All isolated compounds are being described for the first time in this species and were identified on basis of the spectral data (IR and NMR, including APT, DEPT), as well as by comparison with literature data.

Alkaloids of the Hernandiaceae: occurrence and a compilation of their biological activities.

Abstract This chapter presents an overview of the chemistry and pharmacology of the alkaloids found in species of the Annonaceae family. The occurrence of alkaloids from Annonaceae species, as well as their chemical structures and pharmacological activities are summarized in informative and easy-to-understand tables. Within the Annonaceae family, the genera Annona , Duguetia , and Guatteria have led to many important publications. Valuable and comprehensive information about the structure of these alkaloids is provided. The alkaloids of the aporphine type represent the predominant group in this family. Many of the isolated alkaloids exhibit unique structures. In addition to the chemical structures, the pharmacological activities of some alkaloids are also presented in this chapter. Thus, the leishmanicidal, antimicrobial, antitumor, cytotoxic, and antimalarial activities observed for these alkaloids are highlighted. The chapter is presented as a contribution for the scientific community, mainly to enable the search for alkaloids in species belonging to the Annonaceae family.

Alkyl chromone and other compounds from Clusia nemorosa

From Clusia nemorosa a new alkyl chromone, 5,7-dihydroxy-2-(n-heptaeicosanyl)chromone, and n-octacosanoyl ferulate were isolated, besides kaempferol, friedelin, friedelin-3β-ol, β-sitosterol glucoside and betulinic acid. Their structures were elucidated through analysis of spectroscopic data.

Chemical Constituents and Preliminary Antimalarial Activity of Humiria balsamifera

From stems and leaves of Humiria balsamifera St. (Aubl.) Hill (Humiriaceae) were isolated 6 triterpenes [arjunolic acid, 2β,3α-dihydroxy-D:A-friedooleanane, friedelin, α- and β-amyrins and lupeol], a flavonol (quercetin), an isocoumarin (bergenin) a diterpene (phytol), and 2 phytosteroids (sitosterol and stigmasterol)]. Three sesquiterpenoids [caryophyllene oxide (0.9%), humulene epoxide II (0.3%) and trans-isolongifolenone (0.6%)], a diterpene [phytol (29.4%)] and four aliphatic esters [methyl tetra- (0.3%), hexa- (26.6%) and octadecanoate (0.3%), and ethyl tetradecanoate (26.9%)] were identified by GC/MS. Some crude extracts, arjunolic acid and bergenin, were screened in vivo and/or in vitro for their antimalarial activities against a chloroquine resistant strain. Structures of all isolated compounds were elucidated by spectroscopic analysis, including 2D NMR experiments. All isolates, with the exception of the isocoumarin bergenin, and identified compounds as well as antimalarial activities, are described for the first time for this species.

Analysis by GC-MS of the hexane extract of the aerial parts of Aristolochia acutifolia Duchtr

Qualitative analysis by GC–MS of the three non-polar fractions from the hexane extract of Aristolochia acutifolia Duchtr. was carried out and 47 constituents were identified. The major groups of constituents identified away these fractions were sesquiterpenes (spathulenol, 23.1%; β-bisabolene, 9.0%; α-eudesmol, 6.9%; α-selinene, 5.2%; and trans-α-bergamotene, 5.1%), esters (ethyl hexadecanoate, 23.0%; ethyl 9-octadecenoate, 11.6%; and methyl hexadecanoate, 7.9%), phenylpropanoids (myristicin, 35.3%; and elemicin, 15.8%), carboxilic acids (oleic, 22.8%; and palmitic acids, 20.3%), and n-alkanes (pentadecane, 11.7%). Some constituents identified are described for the first time in this genus. Copyright