Juniperus Brevifolia Research Articles

Volatile and molecular analysis of Juniperus brevifolia (Seub.) Antoine, an Azorean endemic species

Chemical and molecular analyses were performed for the characterization of Juniperus brevifolia (Seub.) Antoine (Cupressaceae), an Azorean endemic species. Forty-two individual twig samples were collected at seven Azorean islands (S. Miguel, Terceira, S. Jorge, Pico, Faial, Flores and Corvo). Volatile compounds were isolated by distillation–extraction and analyzed by GC and GC-MS. The volatile oils consisted mainly of monoterpene hydrocarbons (84–96%), limonene (33–87%), α-pinene (1–48%) and β-myrcene (1–5%) being the main components, and cluster analysis showed a high correlation among all samples ( S corr = 0.84). DNA fingerprinting was performed using thirty-seven RAPD and eleven ISSR primers, generating 881 polymorphic bands. Cluster analysis showed a moderate correlation among accessions ( S Dice = 0.43), which grouped according to their geographical origin. Chemical and molecular data did not show superimposable clustering profiles. Although the molecular approaches tested were useful in assessing genetic diversity, no straight correlation could be drawn between chemical and molecular data sets.

A new 4′,7-epoxy-8,3′-oxyneolignan from the acetone extract of Juniperus brevifolia leaves

A new oxyneolignan ( rel-(7α,8β)-3-methoxy-4′,7-epoxy-8,3′-oxyneolignan-4,9,9′-triol) with a scarce C 7– O– C 4 ′ and C 8– O– C 3 ′ epoxy linkage, along with eight known compounds, abieta-8,11,13-triene, sandaracopimara-8(14),15-diene, 6,7-dehydroferruginol methyl ether, 18-hydroxydehydroabietane, sandaracopimara-8(14),15-dien-18-ol, docosanol, sugiol and palmitic acid, were isolated from the chloroform-soluble fraction of the acetone extract from Juniperus brevifolia leaves. Their structures were established on the basis of the spectral evidences and direct comparison with values from literature data.

Biological activity of essential oils from seven Azorean plants against Pseudaletia unipuncta (Lepidoptera: Noctuidae)

AbstractTen essential oils from seven Azorean plant species were evaluated for their insecticidal, ovicidal, feeding‐deterrence and growth inhibition activities against Pseudaletia unipuncta. The oils of Laurus azorica (leaves), and Juniperus brevifolia (leaves) showed strong moderate insecticidal effect on fourth‐instar larvae causing 93.3% and 46.7% mortality, respectively. Juniperus brevifolia (leaves), L. azorica (leaves), Persea indica (leaves), Hedychium gardnerianum (leaves) and Pittosporum undulatum (fruits and leaves) significantly affected the hatching of P. unipuncta eggs (<8% eclosions). Five oils showed significant feeding deterrent activities (L. azorica, 92.4%, J. brevifolia, 93.6%, P. undulatum leaves, 95.5% and fruits, 83.8% and H. gardnerianum, 88.2%). All of the essential oils tested, significantly inhibited the larval growth after 5 days of feeding on the treated diet. Essential oils from L. azorica and J. brevifolia were the most potent growth inhibitors among the oils tested, producing a decrease in the initial larva weight (−14.8 and −14.5 mg, respectively). Our results indicate that L. azorica (leaves), J. brevifolia (leaves), P. indica (leaves), H. gardnerianum (leaves), and P. undulatum (leaves and fruits) can be exploited for the development of bioactive compounds as a new source of agrochemicals. Further emphasis on isolation and identification of active constituents can be useful to develop new environment‐friendly insect control agents.

Conservação e restauro do painel "São Sebastião exortando a fé dos irmãos cativos cristãos Marco e Marceliano" do Museu de Angra do Heroísmo, ilha Terceira, Açores

This paper describes the methodology followed in the conservation and restoration of the panel Saint Sebastian calling on the faith of the Christian captive brothers Marcus and Marcellianus, datable to the late sixteenth century, belonging to the ancient altarpiece in the presbytery of the Church Sao Sebastiao (Saint Sebastian), Terceira Island, Azores, and currently at the Museum of Angra do Heroismo. It begins by presenting an historical overview and an iconographic and artistic study of the panel, which proved crucial to the understanding of the subject and its setting at the time, the church and the whole altarpiece. The double meaning as a testimony of faith and a symbol of national identity in times close to or already in the process of loss of independence from Portugal, is achieved through the hagiographic representation of the patron saint of the church on a base of cedar wood (Juniperus brevifolia), which enables to infer an author or local production. In the late nineties of the twentieth century, this support showed an intense deterioration resulting from colonization by fungi (brown rot) and previous interventions. The work done back than was held by various thinning of the wood and partial filling that allowed the restoration of the physical balance of each one of five boards and the panel as a whole. After this phase, the intervention was stopped, coming to resume in 2007, with the further stabilization of wood, reassembly, repainting survey and treatment of pictorial layer. The methodology was adapted to the most current criteria, keeping only what had once been widely followed in the areas affected by fungal action, with a clear structural instability and inability to recover only by consolidating.

Effects of landslides on the mountain vegetation of Flores Island, Azores

AbstractQuestion: What are the consequences of frequently occurring landslides on vegetation dynamics, floristic and structural diversity?Location: 39°27′N; 31°13′W – Morro Alto, Flores Island, Azores, Portugal.Methods: Six comparable landslides were selected. Plots were placed at the top, slope and toe of landslides. Data on floristic composition and biovolume, demography and size structure of the dominant tree species (Juniperus brevifolia) were collected. Hierarchical agglomerative clustering and Principal Component Analysis were used in order to identify succession stages and compare succession pathways and vegetation recovery in different parts of the landslides.Results: Four stages of primary succession on substrates formed by landslides were identified: pioneer (Festuca‐Sphagnum grassland), assembly (Juniperus‐Festuca‐Sphagnum open scrub), building (Juniperus‐Sphagnum scrub) and mature (Juniperus‐Sphagnum woodland). Concerning J. brevifolia populations, the succession pathways are independent of location on the landslide. However, at the floristic level, there are some differences, mainly in the pioneer stage at the toes of landslides. Better abiotic conditions, resulting in a higher succession rate, are probably responsible for a faster vegetation recovery on landslide toes.Conclusion: Landslides trigger succession processes that enable a massive regeneration of the dominant tree species and existence of species not present in mature forests. They are also responsible for the simultaneous occurrence of vegetation of different structures. Overall, landslides increase the floristic and structural diversity of the vegetation, consequently increasing landscape heterogeneity.

Cyclic patch dynamics in a Macaronesian island forest

We assess if the structural and floristic diversity of Juniperus-Ilex forests from Pico Island (Azores) corresponds to a mosaic of different phases of a forest cycle, by identifying the phases of that cycle and the dynamic relations between them. Eight 100 m 2 plots were placed randomly in areas with structural and floristic differences but having in common the presence of live and/or dead individuals of the dominant tree species ( Juniperus brevifolia ). In each plot the number of seedlings, saplings, and adults as well as canopy height and width and maximum height of live Juniperus brevifolia and Ilex azorica adults were recorded. The floristic composition was determined in a 25 m 2 plot, placed inside each 100 m 2 plot. Juniperus-Ilex forests show a cyclic patch dynamic triggered by the senescence and death of even-aged individuals of J. brevifolia . In this forest cycle, five phases were identified, such as gap, building, mature, initial degenerative and final degenerative. The first two phases are do...

Would species richness estimators change the observed species area relationship?

We evaluate whether the description of the species area relationship (SAR) can be improved by using richness estimates instead of observed richness values. To do this, we use three independent datasets gathered with standardized survey methods from the native laurisilva forest of the Azorean archipelago, encompassing different distributional extent and biological groups: soil epigean arthropods at eight forest fragments in Terceira Island, canopy arthropods inhabiting Juniperus brevifolia at 16 forest fragments of six different islands, and bryophytes of seven forest fragments from Terceira and Pico islands. Species richness values were estimated for each forest fragment using seven non-parametric estimators (ACE, ICE, Chao1, Chao2, Jackknife1, Jackknife2 and Bootstrap; five in the case of bryophytes). These estimates were fitted to classical log–log species–area curves and the intercept, slope and goodness of fit of these curves were compared with those obtained from the observed species richness values to determine if significant differences appear in these parameters. We hypothesized that the intercepts would be higher in the estimated data sets compared with the observed data, as estimated richness values are typically higher than observed values. We found partial support for the hypothesis – intercepts of the SAR obtained from estimated richness values were significantly higher in the case of epigean arthropods and bryophyte datasets. In contrast, the slope and goodness of fit obtained with estimated values were not significantly different from those obtained from observed species richness in all groups, although a few small differences appeared. We conclude that, although little is gained using these estimators if data come from standardized surveys, their estimations could be used to analyze macroecological relationships with non-standardized observed data, provided that survey incompleteness and/or unevenness are also taken into account.

The chemical composition of hexane extract from bark of Juniperus brevifolia

The phytochemical analysis of the bark of Juniperus brevifolia was undertaken for the first time. The GC–MS analysis of the hexane extract from bark of “cedro-do-mato” (J. brevifolia) allowed to identify three rare compounds for the first time in Juniperus genus: 6,7-dehydroferrugin-12-methyl ether, 11-hydroxy-6,7-dehydroferruginol and 6,7-dehydrohinokiol. The results also showed that the chemical composition of the extract were essentially abietane-type diterpenoids with alcohol function (44.9%) and with carbonyl function (8.6%). Fatty acids such palmitic, oleic, stearic and docosanoic acids were the second most abundant family of identified compounds (9.5%) and its value increased (12.7%) after alkaline hydrolysis, mainly due to docosanoic and tetradocosanoic acids. Sterols like sitosterol and stigmast-4-en-3-one, were also present (6.6%), along with esters of sterols (8.4%). Significant quantities of the long-chain aliphatic alcohols (ca 3.7%) were identified in the hexane extract only after alkaline hydrolysis.

Molecular polymorphism and volatile oil composition of the endemic Azorean species, Juniperus brevifolia

Molecular polymorphism and volatile oil composition of the endemic Azorean species, Juniperus brevifolia

Gap dynamics and regeneration strategies in Juniperus-Laurus forests of the Azores Islands

We asked the following questions regarding gap dynamics and regeneration strategies in Juniperus-Laurus forests: How important are gaps for the maintenance of tree diversity? What are the regeneration strategies of the tree species? Thirty canopy openings were randomly selected in the forest and in each the expanded gap area was delimited. Inside expanded gaps the distinction was made between gap and transition zone. In the 30 expanded gaps a plot, enclosing the gap and transition zone, was placed. In order to evaluate the differences in regeneration and size structure of tree species between forest and expanded gaps, 30 control plots were also delimited in the forest, near each expanded gap. In the 60 plots the number of seedlings, saplings, basal sprouts and adults of tree species were registered. Canopy height and width of adult individuals were also measured. The areas of the 30 gaps and expanded gaps were measured and the gap-maker identified. Juniperus-Laurus forests have a gap dynamic associated with small scale disturbances that cause the death, on average, of two trees, mainly of Juniperus brevifolia. Gap and expanded gap average dimensions are 8 and 25 m2, respectively. Gaps are of major importance for the maintenance of tree diversity since they are fundamental for the regeneration of all species, with the exception of Ilex azorica. Three types of regeneration behaviour and five regeneration strategies were identified: (1) Juniperus brevifolia and Erica azorica are pioneer species that regenerate in gaps from seedlings recruited after gap formation. However, Juniperus brevifolia is a pioneer persistent species capable of maintaining it self in the forest due to a high longevity and biomass; (2) Laurus azorica and Frangula azorica are primary species that regenerate in gaps from seedlings or saplings recruited before gap formation but Laurus azorica is able to maintain it self in the forest through asexual regeneration thus being considered a primary persistent species; (3) Ilex azorica is a mature species that regenerates in the forest.

Cytotoxic Activity of Diterpenes and Extracts ofJuniperus brevifolia

The hexane, dichloromethane, acetone and ethanol extracts of the leaves, bark and wood of Juniperus brevifolia were subjected to screening against human tumour cells lines from the cervix (HeLa) and larynx (Hep-2) in two different stages of the cell cycle. The dichloromethane and the chloroform-soluble portions of the acetone extracts of the leaves were active against both tumour cell lines. Chemical investigation of one of the most active extracts (dichloromethane extract from leaves) by preparative chromatography afforded compounds 1-10. Among these, compounds 1-3 were isolated for the first time from the Juniperus genus (18-hydroxyferruginol, 6,7-dehydrototarol and 7alpha-hydroxytotarol) while 4 and 5 are rare as natural products corresponding to (E)- and (Z)-isomers of 8alpha-hydroxy-labda-13(16),14-dien-19-yl-coumarate, respectively. The structures of all compounds were established based on various spectral data. The cytotoxic activity was evaluated for the first time for compounds 1-5 against HeLa and Vero cell lines in lag and log phases of growth. Compound 5 was shown to be active and selective to HeLa in the log phase.

Diterpene constituents of leaves from Juniperus brevifolia

The dichloromethane extract from leaves of Juniperus brevifolia, through chromatographic fractionations yield six compounds: 3β-hydroxy-abieta-8,11,13-trien-7-one, 18-hydroxy-sandaracopimara-8(14),15-dien-7-one, sandaracopimara-8(14),15-dien-18-yl formate; and the first examples of sandaracopimaranes and abieta-8,11,13-triene diterpenoids with a large aliphatic chain on C-18, abieta-8,11,13-trien-18-yl hexadecanoate, 7-oxoabieta-8,11,13-trien-18-yl hexadecanoate, sandaracopimara-8(14),15-dien-18-yl hexadecanoate. Moreover fifteen known compounds were also isolated, some of them for the first time identified on Juniperus genus. The compound abieta-8,11,13-trien-18-yl formate is reported for the first time as a natural product. All the structures were established by spectroscopic methods. 2D NMR techniques have allowed the revision of certain previously reported 13C NMR assignments. Studies on the isolated new compounds showed those possessing a diterpenol ester of a long-chain fatty acid present lipophilicity very distinct from other diterpenoid compounds.

Canopy insect herbivores in the Azorean Laurisilva forests: key host plant species in a highly generalist insect community

This article explores patterns of insect herbivore distribution in the canopy of the Laurisilva forests on seven islands in the Azores archipelago. To our knowledge, this is one of the first extensive study of this type in tree or shrub canopies of oceanic island ecosystems. One of the most frequently debated characteristics of such ecosystems is the likely prevalence of vague, ill‐defined niches due to taxonomic disharmony, which may have implications for insect‐plant interactions. For instance, an increase in ecological opportunities for generalist species is expected due to the lack of predator groups and reduced selection for chemical defence in host plants. The following two questions were addressed: 1) Are specialists species rare, and insect herbivore species randomly distributed among host plant species in the Azores? 2) Are the variances in insect herbivore species composition, frequency and richness explained by host plants or by regional island effects? We expect a proportional distribution of herbivore species between host plants, influenced by host frequency and distinct island effects; otherwise, deviation from expectation might suggest habitat preference for specific host tree crowns. Canopy beating tray samples were performed on seven islands, comprising 50 transects with 1 to 3 plant species each (10 replicates per species), giving 1320 samples from ten host species trees or shrubs in total. From a total of 129 insect herbivore species, a greater number of herbivore species was found onJuniperus brevifolia(s=65) andErica azorica(s=53). However, the number of herbivore species per individual tree crown was higher forE. azoricathan for any other host, on all islands, despite the fact that it was only the fourth more abundant plant. In addition, higher insect species richness and greater insect abundance were found on the trees of Santa Maria Island, the oldest in the archipelago. Insect species composition was strongly influenced by the presence ofE. azorica, which was the only host plant with a characteristic fauna across the archipelago, whereas the fauna of other plant crowns was grouped by islands. The great insect occurrence onE. azoricareflects strong habitat fidelity, but only four species were clearly specialists. Our findings indicate a broadly generalist fauna. The simplicity of Azorean Laurisilva contributed to the understanding of insect‐plant mechanisms in canopy forest habitats.

Bryophyte community composition and habitat specificity in the natural forests of Terceira, Azores

In order to characterize the main areas of natural forest on Terceira Island (Azores), some of the most interesting European forests due to their rich and diverse flora of endemic as well as relict species, six forest stands were studied and their flora inventoried using 226 randomized quadrats, which revealed one anthocerote, 64 liverworts, 41 mosses and 16 macrolichen taxa. The alpha-diversity of the samples is particularly species-rich, some quadrats (30 × 30 cm) including more than 25 bryophyte species. A quantitative analysis of the vegetationenvironment relationships consistently showed that the distributions of the native forest bryophytes and lichens of Terceira are governed by a complex set of factors related to water availability, the status of the substrata and the influences of the vascular plant community. Considering the generally high values of the Sorensen indices and the low number of specialist species found with Lloyd’s index, the differences are more in terms of dominance of species than in terms of species composition. In fact, substratum type was clearly important in the DCA and TWINSPAN analysis using species cover abundance values, largely explaining the distribution of bryophyte species between Juniperus brevifolia (Seub.) Antoine and Laurus azorica (Seub.) Franco bark. The eight putative plant community type groupings achieved with these multivariate methods were able to elucidate some major bryophyte – substratum relationships, that had not previously been considered and they offer a framework for future research.

Essential oils from seven populations ofJuniperus brevifolia (Seub.) Antoine, an endemic species of the Azores

The composition of the essential oils isolated from twigs and from unripe berries of seven populations of Juniperus brevifolia (Seub.) Antoine, an endemic species of the Azorean archipelago, was analysed by GC and GC–MS. All oil samples were dominated by their monoterpene fraction (84–94%), limonene (41–79%) and α-pinene (6–40%) being the main oil components. The sesquiterpene fraction occurred in a concentration range of 1–10%. Diterpenes amounted to 6%, sandaracopimara-8(14),15-diene (up to 5%) being the main component of this fraction. Cluster analysis of the essential oils revealed two distinct groups, one from the twigs and the other from the berries. The enantiomeric composition of α-pinene and limonene showed a clear homogeneity between all the oil samples. Copyright © 2000 John Wiley & Sons, Ltd.

Essential oils from seven populations of Juniperus brevifolia (Seub.) Antoine, an endemic species of the Azores

Essential oils from seven populations of Juniperus brevifolia (Seub.) Antoine, an endemic species of the Azores

Etude systématique du sous-genre Oxycedrus (section oxycedroides) du genre Juniperus (Cupressaceae)

Some biochemical (foliar proanthocyanidins) and morphometric (seeds and galbulos) parameters of the taxa Juniperus oxycedrus L. sensu lato (Mediterranean area), Juniperus cedrus Webb. & Berth, (endemic of the Canary Islands and Madeira) and Juniperus brevifolia (Seub.) Antoine (endemic of the Azores Islands), section oxycedroides, subgenus Oxycedrus, genus Juniperus (Cupressaceae, Conifers), have been studied. Due to their low prodelphinidin content, Oxycedrus junipers from Turkey and Cyprus can be considered as the extreme representatives to the subspecies oxycedrus. Reversibly, the Cretan population studied, with high prodelphinidin content, appears to be the maximum homozygotic expression of the proanthocyanic biosynthesis (subspecies macrocarpa). Proanthocyanic content and the number of the seeds unquestionably link J. brevifolia to the J. oxycedrus complex ; however, we propose to maintain this taxon as a species in view of the small size of its needles. J. cedrus generally contains one seed only by galbulus ; moreover, there is a contradiction between the absolute proanthocyanic content (low) and the relative prodelphinidin content (fairly high). This confers it an unquestionable specific originality. In the end, we propose to consider all the representatives of the Mediterraneo-atlantic group of the oxycedroides section (J. oxycedrus, J. macrocarpa, J. cedrus, J. brevifolia) as diversely related taxa within a Juniperus aggr. oxycedrus complex, with a good chemical and morphogenetical consistency. A parallel has been established with J. aggr. communis, an other representative of the same sub-genus Oxycedrus.

The Fungi of the Azores

The Azores form an archipelago 480 km long, of volcanic islands rising from a submarine ridge. The nearest island to Europe is about 1500 km from Gibraltar, 1250 from Cabo da Roca in Portugal and about 1900 from the English Channel; from the westernmost island it is about 1750 km to Newfoundland. These are truly oceanic islands, of tertiary origin, which have never been in contact with any major land mass and all organisms found on them must have reached them across a wide expanse of ocean.* They have, however, been colonized by Europeans since the I5th century; most of the present woody vegetation consists of introduced trees and shrubs and there has obviously been ample opportunity over a very long period for the accidental introduction of fungi by human activity. The islands fall into three groups, an eastern composed of Sio Miguel and Santa Maria, a central composed of Terceira, SAo Jorge, Graciosa, Pico and Faial and a western of Flores and Corvo. From Santa Maria to Madeira is 740 km, from Sao Miguel to Terceira 12o km. Santa Maria and Graciosa are low lying but most of the islands rise steeply to about 900 m while Pico has an impressive conical peak 2373 m high. The climate resembles that of the Hebrides, with frequent gales, copious rain and a high relative humidity. The mean annual rainfall near the sea at Ponta Delgada is 635 mm and rainfall is considered to increase by 20 per cent every 90 m above sea level. Frost occurs occasionally at 500 m and over, though never on the coast, and owing to frequent mist and low cloud, land above 300 m is always more or less wet, with mean relative humidity seldom falling below 88 per cent. Hence, though the islands are densely inhabited, with housing almost continuous wherever the coastal belt is level enough, permanent habitation above 300 m is regarded as impracticable because of the mist. Though the lavas are alkaline, the high rainfall and extensive leaching of bases renders the soils naturally acid and thin development of Sphagnum occurs in places on the high ground. Some hill pasture, however, has been improved by stripping, fertilizing and reseeding with Lolium and Trifolium repens. The principal industry is cattle raising and the scenery away from the villages is strongly reminiscent of west Wales or north Cornwall, with small green grass fields enclosed by dry stone walls. The native woodland contained few species, notably Myrica faya, Laurus azorica, Juniperus brevifolia and Erica azorica. It has now largely disappeared except from comparatively recent lava flows with a surface too rugged for exploitation. Pittosporum undulatum is now naturalized throughout the archipelago and forms a dominant low