Cherimolacyclopeptide D, a novel cycloheptapeptide from the seeds of Annona cherimola

In a chemical investigation of the seeds of Annona cherimola, a natural cyclic heptapeptide, cherimolacyclopeptide D, were isolated and purified by HPLC with three known cyclic peptides, cherimolacyclopeptides A, B and C. The structure was established by various analyses including MS/MS fragmentation, spectroscopic and chemical evidences.     

Glaucacyclopeptide A from the seeds of Annona glauca

The seeds of Annona glauca furnished two cyclopeptides one of which is novel. The structure was elucidated on the basis on mass spectrometry, 2D NMR methods and amino acids analysis.     

Interpretation of triose phosphate isomerase isozymes in the cherimoya (Annona cherimola Mill.)

Detailed interpretation of triose phosphate isomerase (TPI) isozymes in seed plants has been restricted to only a few species. Three sets of TPI bands are regularly observed in the cherimoya(Annona cherimola), a primitive angiosperm. The slowest, set I, is expressed as one or three bands; the second-slowest set II, as one or two bands; and the fastest, set IV, as one or three bands. A faint set III, just cathodal to set IV, is detected rarely with overstaining. Set IV bands are expressed in macerated extracted pollen but not in pollen leachate. Dissociation-reassociation experiments reveal that the set II bands are heterodimers involving, in part, the enzymes involved in the set I bands. These data combined with those from full-sib progeny analysis lead us to propose a three-locus model to explain the TPI isozyme banding patterns in cherimoya. Sets I and IV consist of the allelic products of individual, single loci. Sets I and II occur in the cytoplasm. Set IV occurs in organelles. Set II isozymes are the intergenic heterodimers of the locus coding for set I and the locus coding for set III. Our results reported here are contrasted with the TPI isozyme patterns known for other vascular plants and suggest that the locus coding for set III may be a duplication of very ancient origin.This work was supported, in part, by funding from the Elvenia J. Slosson Endowment Fund.     

Squamocin-O(1) and squamocin-O(2), new adjacent bis-tetrahydrofuran acetogenins from the seeds of Annona squamosa

Two bis-tetrahydrofuran acetogenins, squamocin-O(1) (1) and squamocin-O(2) (2), were isolated from a MeOH extract of seeds of Annona squamosa L. Their structures were determined by spectral means including precursor-ion scanning mass spectral analysis for their aminal derivatives. The configurations at the oxymethine chiral centers were assigned as 12R,15R,16R,19R,20R,23R,24S,28S,36S for 1 and 12S,15R,16R,19R,20R,23R,24S, 28S,36S for 2, based on 1H NMR analysis of their Mosher's ester derivatives and CD data.     

Mycotrophy of Annona cherimola and the morphology of its mycorrhizae

The mycotrophic character of Annona cherimola (Magnoliales), a tropical/subtropical plantation crop of interest, is described for the first time. This crop seems to depend on mycorrhizae (arbuscular) for optimal growth, with Glomus deserticola being the most effective endophyte tested. Study of the morphology of the arbuscular mycorrhizae in Annona roots showed exclusively intracellular hyphal development, with cell-to-cell fungal passage and an abundance of arbuscules and coiled hyphae within cells. Intercellular distributive hyphae were not observed. The morphology and the pattern of spread of the mycorrhizal colonization were similar for the different endophytes involved and appeared to be dependent on the host root. Such features of mycorrhizal colonization are characteristic of host species lacking intercellular air channels and have been described for some species of ecological interest, but they are not commonly noted in the mycorrhizal literature, especially that dealing with crop species. Some ecophysiological consequences of this pattern of colonization are discussed.     

Lipoxygenase inhibition by novel fatty acid ester from Annona squamosa seeds

Studies on the seeds of Annona squamosa yielded a novel lipoxygenase inhibitor fatty acid ester, (+) - annonlipoxy (1). Compound 1 was screened for its enzyme inhibitory activity against lipoxygenase (E.C.1.14.18.1), exhibiting activity with IC₅₀ 69.05 ± 5.06 μm. Baicalein (IC₅₀ 22.6 ± 0.5 μm) was used as a positive control. Crude extracts of Annona squamosa fruit pulp and seeds were screened for its enzyme inhibitory activity against lipoxygenase and acetylcholinesterase. The crude ethanolic extract of fruit pulp and seeds of Annona squamosa also exhibited lipoxygenase activity with 22.2 and 26.7% inhibition, while the pet.ether extract of seeds of A. squamosa exhibited 52.7% inhibition at a concentration of 40 μg/200 ml. The crude ethanolic extract of seeds of Annona squamosa was also bioassayed for acetylcholinesterase inhibition and it was found inactive.     

Phylogenetics of Annona cherimola (Annonaceae) and some of its closest relatives

Annona cherimola is a woody perennial species in the Annonaceae family that produces edible fruits and has economic importance in several regions of the world with subtropical climates. Together with other 10‐12 species, A. cherimola belongs to the section Atta of the Annona genus with a center of origin in Central America and the Caribbean. Species of the section Atta produce soft skin ripe fruits with raised areoles bounded by recessed furrows. Annona cherimola is the only species of the section naturally found in the Andean region of South America. Currently, no information is available at the molecular level on the phylogenetic relationships of most of the species of Atta and closely related sections in Annona. In order to fill this gap, in this work a phylogenetic approach was performed using five coding and non‐coding plastid DNA regions, to determine the phylogenetic relationships between A. cherimola and other related species included in Atta and other sections of the genus. The results obtained support recent studies that demonstrated the likely Mesoamerican origin of A. cherimola based on biogeographical analysis with SSR markers, rather than the previously considered South American origin hypothesis. In addition, the species belonging to the Atta section did not show monophyly. Finally, A. cherimola and A. pruinosa seem to be phylogenetically close species and additional studies are needed to discern the relations between them.     

Aporphine alkaloids of annona squamosa

The aporphine alkaloids anonaine, roemerine, norcorydine, corydine, norisocorydine, isocorydine and glaucine have been isolated from Annona squamosa.     

Germination ecophysiology of Annona crassiflora seeds

BACKGROUND AND AIMS: Little is known about environmental factors that break morphophysiological dormancy in seeds of the Annonaceae and the mechanisms involved. The aim of this study was to characterize the morphological and physiological components of dormancy of Annona crassiflora, a tree species native to the Cerrado of Brazil, in an ecophysiological context. METHODS: Morphological and biochemical characteristics of both embryo and endosperm were monitored during dormancy break and germination at field conditions. Seeds were buried in the field and exhumed monthly for 2 years. Germination, embryo length and endosperm digestion, with endo-beta-mannanase activity as a marker, were measured in exhumed seeds, and scanning electron microscopy was used to detect cell division. The effect of constant low and high temperatures and exogenous gibberellins on dormancy break and germination was also tested under laboratory conditions. KEY RESULTS: After burial in April, A. crassiflora seeds lost their physiological dormancy in the winter months with lowest monthly average minimum temperatures (May-August) prior to the first rainfall of the wet season. The loss of physiological dormancy enabled initiation of embryo growth within the seed during the first 2 months of the rainy season (September-October), resulting in a germination peak in November. Embryo growth occurred mainly through cell expansion but some dividing cells were also observed. Endosperm digestion started at the micropylar side around the embryo and diffused to the rest of the endosperm. Exogenous gibberellins induced both embryo growth and endo-beta-mannanase activity in dormant seeds. CONCLUSIONS: The physiological dormancy component is broken by low temperature and/or temperature fluctuations preceding the rainy season. Subsequent embryo growth and digestion of the endosperm are both likely to be controlled by gibberellins synthesized during the breaking of physiological dormancy. Radicle protrusion thus occurred at the beginning of the rainy season, thereby maximizing the opportunity for seedlings to emerge and establish.     

Anxiolytic-like actions of the hexane extract from leaves of Annona cherimolia in two anxiety paradigms: possible involvement of the GABA/benzodiazepine receptor complex

A hexane extract of leaves of Annona cherimolia produced anxiolytic-like actions when administered to mice and tested in two animal models of anxiety: the mouse avoidance exploratory behavior and the burying behavior tests. In order to discard unspecific drug-actions on general activity, all treatments studied in the anxiety paradigms were also analyzed in the open field test. Results showed that A. cherimolia induced anxiolytic-like actions at the doses of 6.25, 12.5, 25.0 and 50.0 mg/kg. Picrotoxin (0.25 mg/kg), a GABA-gated chloride ion channel blocker, antagonized the anxiolytic-like actions of A. cherimolia, while a sub-effective dose of muscimol (0.5 mg/kg), a selective GABA_A receptor agonist, facilitated the effects of a sub-optimal dose of A. cherimolia (3.12 mg/kg). Thus, the involvement of the GABA_A receptor complex in the anxiolytic-like actions of A. cherimolia hexane extract is suggested. In addition the extract was also able to enhance the duration of sodium pentobarbital induced sleeping time. Taken together, results indicate that the hexane extract of A. cherimolia has depressant activity on the Central Nervous System and could interact with the GABA_A receptor complex. On the other hand, the chromatographic separation of this extract led to the isolation of palmitone, and β-sitosterol as major constituents. In addition a GC-MS study of some fractions revealed the presence of several compounds such β-cariophyllene, β-selinene, α-cubebene, and linalool that have been reported to show effects on behavior that could explain some of the extract effects.     

Germacranolides from seeds of the endangered Umbelliferae species Rouya polygama

From the etheral extract of Rouya polygama Coincy seeds (Umbelliferae) six new germacranolides 1-6 were isolated. The structures were elucidated by chemical methods and spectroscopic analysis. Compounds 1 and 4 exhibited activity against Artemia salina larvae.     

Quaternary isoquinoline alkaloids from Xylopia parviflora

From the quaternary alkaloidal fraction of the bark and the root of Xylopia parviflora (Annonaceae), four isoquinoline alkaloids, xylopinidine, dehydrocoreximine, N, N-dimethylanomurine and N-methylphoebine were isolated along with the known compounds, pycnarrhine, lotusine, 6,7-dimethoxy-2-methyl-isoquinolinium salt, 1,2-dehydroreticuline, (-)-phellodendrine, (+)-tembetarine, (-)-litcubine, (+)-magnoflorine, tetradehydroreticuline, (-)-oblongine, (+)-menisperine, (+)-N-methylcorydine, stepharanine, (+)-xanthoplanine, dehydrodiscretine, jatrorrhizine and palmatine. 3,4-Dihydro-6,7-dimethoxy-2-methyl-isoquinolinium and N-methylpurpuerine were isolated as natural products for the first time. Their structures were determined on the basis of spectroscopic evidence.     

Flavonoid triglycosides from the seeds of Syzygium aromaticum

Two new apigenin triglycosides, apigenin 6-C-[beta-D-xylopyranosyl-(1'-->2')-beta-D-galactopyranoside]-7-O-beta-D-glucopyranoside and apigenin 6-C-[beta-D-xylopyranosyl-(1'-->2')-beta-D-galactopyranoside]-7-O-beta-D-(6-O-p-coumarylglucopyranoside) were isolated from the ethanol extract of the seeds of Syzygium aromaticum. Their structures were elucidated by chemical and spectral analysis (UV, FABMS, 1H, 13C NMR, HMQC, HMBC, NOESY and DEPT).     

Secondary and tertiary isoquinoline alkaloids from Xylopia parviflora

From the secondary and tertiary alkaloidal fractions of the root and the bark of Xylopia parviflora (Annonaceae), the isoquinoline alkaloids, 10,11-dihydroxy-1,2-dimethoxynoraporphine and parvinine were isolated, along with 39 known alkaloids. Their structures were determined on the basis of analysis of spectroscopic data.     

Bioassay-guided isolation of antifungal cyclopeptides from the deep-sea-derived fungus Simplicillium obclavatum EIODSF 020

Two new cyclopeptides simplicilliumtides N and O (1 and 2) along with three known analogues verlamelins A, B and simplicilliumtide J (3-5) were isolated from the deep-sea-derived fungal strain Simplicillium obclavatum EIODSF 020 by bioassay-guided isolation method. Their structures of 1 and 2 were elucidated by spectroscopic analysis, and their amino acid configurations were determined by Marfey’s method. All isolated compounds showed significant antifungal activity against two phytopathogenic fungi Alternaria solani and Colletotricum asianum with MIC values of 0.195–6.250 μg/disc. This study suggests the fungal strain S. obclavatum EIODSF 020 is a new source for developing natural fungicides.     

Archaeological evidence of cherimoya(Annona cherimolia Mill.) and Guanabana(Annona muricata L.) in ancient Peru

Archaeological Evidence of Cherimoya (Annona cherimolia Mill.)and Guanabana (Annona muricata L.)in Ancient Peru. Economic Botany 58(4):509-522, 2004. The results of this study confirm the presence of both guanabana and cherimoya in ancient Peru. Our evidence consists of linguistic data and botanical remains of plants that were found in archaeological contexts, as well as ceramic phytomorphic representations of the fruits.

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Evidencias arqueológicas de chirimoya (Annona Cherimolia Mill.) YGuanabana (Aannona muricata L.)en el Antiguo Perú

Résumé  Con el presente trabajo se demuestra, que tanto la guanábana como la chirimoya han sido conocidas y utilizadas en el antiguo Perú. Las evidencias consisten en datos linguistícos y restos botánicos de dichas plantas que han sido encontrados en contextos arqueológicos y representaciones en cerámica de sus frutos.