Manual de introduçäo aos computadores
Richman, Ellen
1987
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O sumário pormenorizado da lição que agora se apresenta, insere-se na disciplina de Biologia Celular, disciplina do 1° ano, lº semestre, da estrutura curricular dos cursos de Licenciatura em Ciências Agrárias, Ramo Agrícola e Ramo Animal, de Engenharia Florestal e de Engenharia do Ordenamento e Recursos Naturais, cujo programa se encontra em anexo.
Trata-se de uma disciplina de carácter geral onde são ministrados aos alunos princípios e conceitos básicos sobre a diversidade do mundo vivo, constituintes, organização e funcionamento celular, tendo em vista a compreensão de uma forma integrada das inter-relações entre seres e do funcionamento celular enquanto unidade estrutural da sua constituição.
O ponto do programa que agora nos propomos abordar, “Cultura de tecidos vegetais: princípios e aplicações”, surge com intenção de proporcionar aos alunos alguns aspectos de aplicação dos conhecimentos já obtidos permitindo-lhes a percepção da importância dos mecanismos per si no funcionamento e nas respostas dos seres vivos de acordo com todos os factores que sobre eles exercem influência. Em concreto, é intenção deste ponto permitir aos alunos uma primeira abordagem de modelos de desenvolvimento vegetal e de que forma eles podem ser utilizados não só para a sua própria compreensão mas, também, alertar os alunos para potenciais aplicações destas metodologias que são hoje meios indispensáveis noutras áreas do saber. Este aspecto permitirá estabelecer uma ligação com futuras disciplinas curriculares, como sejam a Genética, a Fisiologia e Nutrição Vegetal, a Ecofisiologia, as Técnicas de Melhoramento Florestal, o Melhoramento Vegetal e as Tecnologias de Multiplicação de Plantas, de acordo com os respectivos cursos, e onde estes temas serão retomados e desenvolvidos tendo em vista as suas especificidades.
Trata-se, contudo, da apresentação de assuntos em que os alunos poderão deparar com algumas dificuldades de compreensão, uma vez que temos consciência que para o seu global entendimento e percepção das suas potenciais implicações, tornava-se necessário que os alunos já tivessem conhecimentos que apenas irão ser adquiridos posteriormente, em especial nas disciplinas atrás referidas. No entanto julgamos que esta é uma questão de dialéctica, inerente ao próprio sistema de ensino/aprendizagem, isto é, a interdependência e a interligação entre matérias ao longo de uma formação global de um curso superior.
Como última referência uma breve explicação. O conteúdo deste ponto que irá ser apresentado durante sessenta minutos, em situação real de ensino está programado para duas a três horas, uma vez que consideramos de grande importância a participação e intervenção dos alunos, quer por iniciativa própria, quer por iniciativa do docente, numa tentativa de os manter sempre que possível com uma atitude activa e não de meros espectadores. Além disso permitirá ao docente ir resolvendo alguns pequenos problemas de compreensão a que atrás fizemos referência.
Comunicação da qual só está disponível o resumo.
A Escola Superior Agrária de Castelo Branco e o Programa CIÊNCIA.
A propagação de plantas por sistemas in vitro.
Centro de Biotecnologia de Plantas da Beira Interior.
O Centro de Biotecnologia de Plantas da Beira Interior (CBPBI) é uma infraestrutura do Sistema Científico e Tecnológico Nacional, criado na Escola Superior Agrária de Castelo Branco ao abrigo de um protocolo de colaboração técnica e científica entre o Instituto Politécnico de Castelo Branco, a Universidade da Beira Interior, o Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas da Universidade de Campinas, Brasil e o Biocant Park de Cantanhede.
Comunicação apresentada no Simpósio de Propagação Vegetativa de Espécies Lenhosas que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 18 a 20 de Outubro de 1996.
O evento foi organizado pelo Centro de Estudos de Desenvolvimento Regional (CEDER) do Instituto Politécnico de Castelo Branco.
Este estudo teve como objectivo verificar a influência da intensidade luminosa durante a aclimatização de rebentos de castanheiro (Castanea sativa x Castanea crenata) regenerados in vitro, tendo sido submetidos a dois tratamentos de luz, de 250 m mol m-2s-1 e 150 m mol m-2s-1. Para a análise dos tratamentos foram quantificados parâmetros de análise de crescimento.Verificou-se que as plantas que foram sujeitas a uma irradiância de 250 m mol m-2s-1 apresentaram maior crescimento e consequentemente maior quantidade de biomassa, desenvolvendo assim sistemas radiculares e aéreos com maior potencial, que os desenvolvidos nas plantas sujeitas a uma irradiância de 150 m mol m-2s-1.
Referem-se alguns dos aspectos históricos que mais contribuíram para o desenvolvimento do conhecimento na área da cultura de tecidos vegetais, bem como a grande diversidade de aplicações e utilização destas metodologias, desde os estudos fisiológicos, interacções substâncias/planta, produção de metabolitos secundários, manipulação genética e melhoramento até à sua utilização como uma poderosa metodologia na multiplicação de plantas, quer por rebentamento adventício, axilar quer por embriogénese somática. Faz-se uma descrição sucinta dos aspectos que maior impacto têm vindo a ter com a utilização destas metodologias nos diferentes grupos de culturas vegetais, nomeadamente nas culturas extensivas, hortícolas, ornamentais, fruteiras e florestais.
Referem-se alguns dos aspectos históricos que mais contribuíram para o desenvolvimento do conhecimento na área da cultura de tecidos vegetais, bem como a grande diversidade de aplicações e utilização destas metodologias, desde os estudos fisiológicos, interacções substâncias/planta, produção de metabolitos secundários, manipulação genética e melhoramento até à sua utilização como uma poderosa metodologia na multiplicação de plantas, quer por rebentamento adventício, axilar e embriogénese somática.
Faz-se uma descrição sucinta dos aspectos que maior impacto têm vindo a ter com a utilização destas metodologias nos diferentes grupos de culturas vegetais, nomeadamente nas culturas extensivas, hortícolas, ornamentais, fruteiras e florestais.
O diagnóstico das causas de mortalidade acentuada dos sobreiros nos concelhos de Castelo Branco, Vila Velha de Ródão e Idanha-a-Nova, veio contribuir para um conhecimento quantificado da situação destes ecossistemas. Foi assim possível avaliar a acção de vários factores relativos à situação fisiológica, ecológica, edafo-climática, sanitária, de exploração e de condução destes sistemas agro-florestais e também das interacções entre eles. Concluiu-se que a situação de declínio verificada é consequência da acção conjugada dos factores acima referidos, que actuam a médio/longo prazo e como tal difíceis de controlar. Consideramos também que o futuro destes ecossistemas, de grande importância económica e ecológica, depende eventualmente de um reordenamento do espaço por eles ocupado, o qual deverá ser definido por condicionantes de ordem não só florestal mas também de opções agrícolas e sócio-económicas que conduzam a um desenvolvimento sustentado das zonas de montado.
Great advances have been made but some cultured plantlets still having a poor performance during the ex vitro stages and more specifically during the acclimatization and the nursery establishment stages. The problem is highly complex and requires the fast adaptation of plants growing in artificial conditions when transferred to the natural conditions. Until now, there is no consensus on the better strategy to obtain a higher efficiency of the propagation protocols while optimising acclimatization success. In this study we present the results of growth analysis of in vitro-regenerated chestnut hybrid plantlets (Castanea sativa x C. crenata), during the acclimatization stage, using two CO2 concentrations (350 µLL-1 and 700 µLL-1) at 250 µmol m- 2 s-1 as irradiance level (PPFD). Elevated CO2 did not affect the survival rate and it was susceptible to increase progressive autotrophy, expressed by a significant increase in relative growth, shoot/root ratio and leaf area ratio (LAR). For both CO2 concentrations, the plants are successfully acclimatized and they are in good conditions to be transferred to a greenhouse to continue their development for the rest of the season, and in the next winter/spring they can go to the field. The plants under elevated CO2 showed a higher stomatal frequency but the new leaves developed at the end of acclimatization revealed a gradual normal stomatal morphology and they reduced the stomatal frequency. Their morphology showed an effective water loss control, which is one of the most important problems during this critical phase of the autotrophic competence acquiring process. The net photosynthesis rate (A) was similar in both treatments but the plants acclimatized at elevated CO2 showed an increase in maximum photosynthetic rate (Amax), and this can lead to a better physiological development. The different analysed leaf types showed a marked increment of the maximum photosynthetic rate as the new leaves developed during the acclimatization stage. Net photosynthesis rate and the maximum photosynthetic rate are light dependent, and are positively affected by the highest irradiance level. We think that the gains that we have achieved with the use of elevated CO2 can be more significant if a higher light intensity can be used instead because they have a better response capacity to an increment of the level of irradiance.
Com o objectivo de desenvolver metodologias de micropropagação de Lavandula luisieri, foram realizados um conjunto de ensaios tendo como material vegetal explantes provenientes de germinação de sementes in vitro. Os ensaios de multiplicação estabelecidos com explantes secundários provenientes das plantas in vitro da população stock mostraram que a 6- benzilaminopurina se mostrou mais eficaz, comparativamente com a cinetina, na promoção e desenvolvimento dos rebentos tendo na concentração de 0.44 µM sido obtidos uma média de 2.2 rebentos com taxa de multiplicação de 3 e comprimentos de 20.9 mm. Contudo a utilização de concentrações mais elevadas de 6-benzilaminopurina são susceptíveis de promoverem elevadas taxa de vitrificação (35%) com consequente perda das culturas. Durante esta fase de multiplicação registou-se a formação de raízes nos rebentos tendo as percentagens de enraizamento sido maiores nos meios com cinetina, 57.5% com 0.46 µM, e no controlo. A aclimatização destas plantas foi feita com 100% de sobrevivência o que indicia o bom estado fisiológico das plantas regeneradas in vitro.
A realização desta Jornada Técnica sobre o Castanheiro, inseriu-se no âmbito da divulgação do Potojecto PAMAF 6127.
Comunicação apresentada no Simpósio de Propagação Vegetativa de Plantas Lenhosas que decorreu em Castelo Branco, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco, de 18 a 20 de Outubro de 1996.
Comunicação oral apresentada no II International Symposium on Acclimatization and Establishment of Micropropagated Plants que decorreu em 2004 em Cancún, no México.
The aim of this study was to compare two rooting environmental conditions for root development, in vitro and ex vitro, and their influence in anatomical differentiation.
Comunicação oral da qual só está disponível o resumo.
O objetivo deste trabalho foi realizar um estudo comparativo em microplantas de castanheiro com dois sistemas de expressão e desenvolvimento radicular, in vitro e ex vitro, e com duas intensidades luminosas (150 e 250 μmol m-2 s-1) durante a aclimatização, e a sua influência no desenvolvimento das microplantas durante esta fase, através da quantificação de parâmetros fotossintéticos. A concentração de clorofilas, após os tratamentos de aclimatização, dependeu quer do tipo de sistema radicular que as plantas possuíam no início da aclimatização, quer do regime luminoso a que as plantas estiveram submetidas.
As plantas com enraizamento in vitro e aclimatizadas sob menor irradiância foram as que apresentaram valores superiores para a clorofila total (7,74 mg g-1ps), mas com o valor mais baixo na razão entre clorofila a/b (2,7).
Quando comparamos os valores registados para os parâmetros fotossintéticos das plantas dos diferentes tratamentos, verificamos que as taxas de fotossíntese aparente vão gradualmente aumentando à medida que as novas folhas se vão desenvolvendo (0,75 μmol CO2 m-2 s-1 nas folhas persistentes e 3,43 μmol CO2 m-2 s-1 na folha 3 das plantas aclimatizadas a 250 μmol m-2 s-1). O mesmo acontece na capacidade fotossintética (3,93 μmol O2 m-2 s-1 nas folhas persistentes e 7,87 μmol O2 m-2 s-1 na folha 3 das plantas aclimatizadas a 250 μmol m-2 s-1). Estes valores foram tendencialmente superiores nas plantas com enraizamento ex vitro e aclimatizadas a maior irradiância, pelo que a um melhor sistema radicular e uma maior disponibilidade luminosa correspondeu um acréscimo na competência fotossintética, o que resultou num melhor desenvolvimento morfofisiológico das plantas.
Comunicação apresentada no Simpósio Propagação Vegetativa de Espécies Lenhosas que decorreu de 18 a 20 de Abril de 1996, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco.
Endogenous levels of IAA, IAAsp and IBA were quantified during the first 8 days of in vitro rooting of the chestnut hybrid, clone M3 by high performance liquid chromatography. Rooting was induced either by dipping the basal ends of the shoots into 1 gl-1 IBA solution for 1 minute or by subculturing the shoots on agar rooting medium with 3 mgl-1 IBA for 5 days. For root development the induced shoots were transferred to auxin-free agar medium. Auxins were measured in the apical and basal parts of the shoots by means of high performance liquid chromatography. Endogenous levels of IAA and IAAsp were higher in IBA-treated shoots than in control shoots. In extracts of the basal parts of the shoots, the concentration of free IAA showed a transient peak at day 2, in both root inductive methods, a subsequent gradual decrease for the remainder of the time course was observed. The concentration of IAAsp peaked at day 6 in extracts of the basal parts of shoots induced with 3 mgl-1 IBA for 5 days, whereas shoots induced by dipping showed an initial increase until day 2, and then remained stable. In extracts from basal shoot portions induced by dipping and by IBA in the medium, IBA concentration showed a transient peak at 24 h and 48 h, respectively, remaining stable after day 4 for the dipping method, whilst showing a significant drop between day 4 and 6 for the other induction treatment. All quantified auxins remained at a relatively low level, virtually constant, in extracts from apical shoot portions, as well as in extracts from control of non-rooting shoots.
The aim of the present study was to evaluate the total phenolic content and antioxidant activity of aqueous extracts of Pterospartum tridentatum samples, collected in three locations in Portugal, at diferente vegetative stages.
The aerial parts of Pterospartum tridentatum, a wild growing species in Portugal used in
traditional medicine and gastronomy, were harvested at different stages (vegetative phase, flowering
phase and beginning of dormancy) in two locations in Portugal (Malcata and Gardunha mountains),
and the respective aqueous extracts have been studied. The influence of the seasonal variation in the
extraction yield, total phenolic content and antioxidant activity was evaluated. The extraction was
carried out in boiling water in consecutive steps. After each step, the aqueous extract was separated
and fresh water was added maintaining the same plant material. The procedure was repeated seven
times, within an overall time period of 180 minutes.
Higher extraction yields were achieved with plant stems collected at the vegetative phases, either from
Malcata or Gardunha regions. The total phenolic content of the extracts from Malcata plants ranged
from 273 mg to 400 mg gallic acid equivalent/g dry matter, which was quite similar to that determined
for extracts from Gardunha (245 to 394 mg gallic acid equivalent/g dry matter). The antioxidant activity
was determined by the radical scavenging activity method using 2,2-diphenyl-1-picrylhydrazyl radical
(DPPH). The greatest radical scavenging activity was observed in the flowers extracts, even though all
extracts produced presented a good antioxidant activity. Furthermore, the antioxidant activity was not
affected by the exposure of the plant material at 100ºC for long periods of time (180 min).
The results show that Pterospartum tridentatum has a great potential to be used as a new source of
natural antioxidants for the food industry.
Tendo em vista a valorização deste recurso natural, este trabalho tem como principal objectivo a produção de extractos aquosos das partes aéreas da carqueja e a sua caracterização.
Comunicação da qual só está disponível o resumo.
Identificação de compostos bioativos em plantas silvestres e plantas in vitro de Pterospartum tridentatum (L.) Willk.
Atividade antioxidante e antimicrobiana de extratos de plantas de Pterospartum tridentatum (L.) Willk. in vitro e silvestres.
Development of a spirit drink produced with strawberry tree (Arbutus unedo L.) fruit and honey.
L. stoechas subsp. luisieri is one of the five spontaneous species of the genus Lavandula that occurs spontaneously in Portugal. The chemical profile and antifungal activity of L. stoechas subsp. luisieri essential oils were investigated. The essential oil of two phenological stages was isolated by hydrodistillation and their chemical components analyzed by GC-FID/GC-MS. The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of both essential oils were determinate to verify antifungal activity against different strains of fungi isolated from strawberry tree. The fungi tested were Aspergillus carbonarius, Rhizopus stolonifer, Penicillium brevicompactum, Aureobasidium pullulans and Saccothecium rubi. Essential oils were
characterized by a high percentage of oxygenated monoterpenes (46-64%) such as trans-α-necrodyl acetate (12.58%), fenchone (5.97%), 1,8-cineole (4.84%) and 5-methylene-2,3,4,4-tetramethylcyclopenten-2-enone (10.97%) were the major compounds in essential oil from dormancy stage, while the main compounds in flowering stage were trans-α-necrodyl acetate (26.90%), trans-α-necrodol (13.02%), lavandulyl acetate (6.53%) and linalool (5.82%). A strong antifungal activity of the essential oils was found against all strains, with MIC and MFC values ranged from 0.07-0.29 µL/mL and 0.58-9.33 µL/mL, respectively.
Essential oils of Lavandula stoechas subsp. luisieri as antifungal agent against fungi from strawberry tree fruit
: Cistus ladanifer L. (Cistaceae) occupies extensive areas as a dominant species (shrublands) or
is associated to other major forest typologies in the Iberian Peninsula. Cistus ladanifer shrublands are
mostly present in oligotrophic lands with little valorisation and management and as they develop over
the years (up to 20-years-old) they promote the ignition and perpetuation of fire. To contribute to the
proper management and valorisation of such systems, a 5-year-old dense shrubland was evaluated for
its labdanum resin, seeds, and biomass productivity using different non-destructive harvest periodicities
(annual and biennial) and seasons (early, mid-, and late summer), in a two-year case-study. Annual harvest
modality maximized labdanum resin productivity (reaching 230 ± 50 kg·ha−1
·2 years−1 at late summer)
and photosynthetic biomass productivity. In contrast, a biennial harvest yielded significant amounts
of more diversified products. It maximized seeds productivity (reaching 75 ± 41 kg·ha−1
·2 years−1
independently of the summer season) and lignified biomass. However, it also reached a labdanum resin
productivity of 134 ± 20 kg·ha−1
·2 yearrs−1 at late summer and a photosynthetic biomass productivity
around two times lower than the annual harvest. In this study, we propose two modalities of periodic
harvest to be considered as proper long cycle management practices of rockrose lands. It intends to
minimize fire risks, break the vegetation auto-succession mechanism, and increase profit from nonproductive lands based on three direct outputs with a myriad of applications and valorisation pathways.
This work aimed to optimize the in vitro multiplication phase of the gore (Pterospartum tridentatum (L. Wilk)).
The morphology and physiology of plants grown in vitro are regulated by various environmental factors such as light, temperature, humidity and carbon dioxide. Light, in its various parameters such as spectral quality, photon flux and photoperiod, is an important factor among these and generally influences the overall growth and development of plants in vitro. Light sources commonly used for in vitro plant culture are fluorescent lamps, although some research and commercial laboratories also use sodium metal or incandescent metal halide lamps. The spectral of those lamps range from 350 to 750 nm and contain blend lights that differentially affect in vitro plant growth. Recently, light emitting diodes (LEDs) have been developed and are nowadays used as an alternative source of fluorescent light for the development of plants both in greenhouses and in vitro culture rooms. In order to test the influence of these two types of light during multiplication phase, a multiplicity experiment was carried out using two species: a chestnut hybrid (Castanea sativa x C. crenata), clone M2 and the prickled broom (Pterospartum tridentatum (L.) Willk.), Malcata ecotype. Two types of light were tested, "cool white" fluorescent light and LED light with blue and red colors. It was found that LED illumination exerted a significant positive effect on the differentiation of shoots in the case of prickled broom (5.6 instead of 4.9 split shoots under fluorescent light). In the parameters of shoot length, we found that this type of lighting favored the elongation in both species. Regarding the parameters of fresh and dry weight, LED lighting caused a greater effect on the chestnut than on prickled broom. Some physiological parameters (chlorophylls, carotenoids and proteins) were also analyzed and showed to be influenced by the type of light during the development of microplants.
Cistus ladanifer has a well-defined taxonomic identity. 2,2,6-trimethylcyclohexanone may be an authenticity and taxonomic marker. Its traits and applications make it a possible economic resource fitted for Mediterranean areas. Cistus ladanifer is a dominant shrub species endemic to the western Mediterranean region. Due to its dominant nature and its potential ecological, aromatic or pharmacological applications, C. ladanifer has been the object of numerous studies. In this review current knowledge on different aspects of this species is summarized, from its taxonomy to its chemical characterisation or its competitive traits. There are no doubts about the taxonomic entity of C. ladanifer, although the recognition of infraspecific taxa deserves more attention. Given that the fragrant exudate of C. ladanifer holds a very specific composition, one species specific carotenoid, 2,2,6-trimethylcyclohexanone, derivative is proposed as an authenticity marker for uses of C. ladanifer in pharmacological or aromatic industries. Evidence is also gathered on the extreme adaptation of C. ladanifer to stressful conditions in the Mediterranean region, such as the ability to survive in low hydric and high solar exposition conditions, presistence in poor and contaminated soils, and growth inhibition of several other plants through the release of allelochemicals. Thus, the finding of potential applications for this plant may contribute to enhance the economic dimension of derelict lands, such as mine tailings or poor agricultural Mediterranean areas.
Stevia rebaudiana Bertoni, Asteraceae, is an herbaceous perennial plant native to Paraguay. This species is considered since ancient times a medicinal plant with important bioactive compounds and pharmacologic and food properties, namely diterpenes glycosides. The high natural sweetener potential stevioside and rebaudioside A produced by S. rebaudiana plants are suitable sucrose substitutes, and their obtention is influenced by environmental, phytosociological, and genetic factors. The plants' genetic profile and sweet potential depiction are needed for suitable plant selection for improvement and deployment. Thirty-one S. rebaudiana accessions grown in the same plot where leaves samples were collected in early 2019, were genotyped using six microsatellite markers, including two steviol glycosides biosynthesis functionally involved markers. Additionally, an aqueous extract of each sample was obtained in a water bath and purified by SPE for stevioside and rebaudioside A quantification by normal phase HPLC. Stevioside and rebaudioside A contents varied between 0.53-7.36% (w w-1) and 0.37-3.60% (w w-1), respectively. Two genotypes displayed interesting ratios of rebaudioside A/stevioside (number 3 and 33). The level of genetic similarity between genotypes was tested through a pairwise similarity coefficient, and two groups of individuals had the same fingerprinting. Strong relatedness was found within genotypes, possibly due to cloning, thus, influx of new germplasm ought to be made to prevent mating between relatives, and for further selection and genetic improvement.
Cistus ladanifer L. exudes a phenolic and terpenoid resin with interesting bioactive and aromatic
properties. Despite its high abundance in the wild, this plant can be cultivated to advantage on oligotrophic
and trace-elements contaminated soils. Plant tissue culture may be used to produce specific metabolites
or for clonal propagation of specific genotypes for plantation. From a biotechnological perspective this
is the second study that has attempted in vitro propagation of C. ladanifer from adult plant material.
Its goal was to evaluate the potential of leaf and internodal stem explants from C. ladanifer for in vitro
tissue culture. Three plant growth regulators were tested: 2,4-Dichlorophenoxyacetic acid (2,4-D),
6-Benzylaminopurine (BAP), and 1-Naphthaleneacetic acid (NAA). From both explants, shoots were
regenerated under the influence of BAP (38%) and two types of compact calli were induced: dark green
calli were induced under the influence of BAP (above 70%) and light green calli were induced under the
influence of 2,4-D with or without BAP (100%). Light green calli grew between 558 and 708% during
subsequent subcultures and showed rhizogenic capacity when the amounts of BAP were lower than of
2.4-D, but they showed low potential for shoot organogenesis. Dark green calli were associated with shoot
organogenesis. The suitability of the two calli lines to produce metabolites and their transposition to
liquid cultures is worth further study in comparison to organ in vitro cultures.
Globally, climate change and wildfires are disrupting natural ecosystems, thus setting
several endemic species at risk. The genus Lavandula is widely present in the Mediterranean region
and its species, namely, those included in the section Stoechas, are valuable resources of active
compounds with several biological assets. Since ancient times lavenders have been used in traditional
medicine and for domestic purposes. These species are melliferous, decorative, and essential oilproducing plants with a high economic interest in the pharmaceutical, flavor, fragrance, and food
industries. The essential oils of Lavandula section Stoechas are characterized by high amounts of
1,8-cineole, camphor, fenchone, and specifically for L. stoechas subsp. luisieri one of the major
compounds is trans-α-necrodyl acetate. On the other hand, the diversity of non-volatile components
like phenolic compounds, such as phenolic acids and flavonoids, make these species an important
source of phytochemicals with pharmacological interest. Rosmarinic, caffeic, and salvianolic B acids
are the major phenolic acids, and luteolin and eriodictyol-O-glucuronide are the main reported
flavonoids. However, the concentration of these secondary metabolites is strongly affected by
the plant’s phenological phase and varies in Lavandula sp. from different areas of origin. Indeed,
lavender extracts have shown promising antioxidant, antimicrobial, anti-inflammatory, and anticancer
properties as well as several other beneficial actions with potential for commercial applications.
Despite several studies on the bioactive potential of lavenders from the section Stoechas, a systematized
and updated review of their chemical profile is lacking. Therefore, we carried out the present review
that gathers relevant information on the different types of secondary metabolites found in these
species as well as their bioactive potential.
Cistus ladanifer L. (Cistaceae) is an endemic and abundant resource in the Iberian
Peninsula and North Africa. This plant exudes an aromatic resin nowadays valued in the
perfumery and fragrance industry. Traditional processes for the extraction and isolation
of such resin use boiling water or alkaline water followed by acidic precipitation.
However, a concern arises about the effluents resulting from these extraction processes.
To overcome this concern, labdanum resin was extracted with Na2CO3 solution (25 g/L)
at 60 oC and precipitated with sulphuric acid (5 M). The residual water was evaluated
regarding total phenolic content, suspended solids, electric conductivity, and sulphate,
sodium, magnesium, and calcium content. The effluent was characterized by a total
phenolic content of 1245 ± 455 mgGAeq/L, 1338 ± 101 mg/L of suspended solids, pH of
approximately 2, electric conductivity of 34.8 ± 0.7 mS/cm, 22284 ± 710 mg/L of
sulphate, 9696 ± 1072 mg/L of sodium, 3.97 ± 0.24 mg/L of magnesium, 3.52 ± 0.80
mg/L of calcium, and a Sodium Adsorption Ratio of 876 ± 112. Because the values were
far from the limit values set by Portugal decree-law 236/98 for residual waters discharged
and irrigation waters, it was concluded that efforts should be made to optimize the
extraction process. In that regard, a factorial designed experiment was done to evaluate
the effect of Na2CO3 concentration (0; 2.5; and 25 g/L), extraction temperature (60 and
100 oC) and acidification extent (pH 2, neutralization, and no acidification) on the residual
water quality and on the yield of labdanum resin extraction. Alkalinization and
acidification are important to obtain high resin extraction yields (Andalusian vs.
Zamorean process), but mostly alkalinization may be reduced to meet sulphate criteria
for discharge without significantly affecting resin extraction yields. Despite that, to meet
salinity criteria for irrigation waters a higher reduction in alkalinization is needed for
Andalusian processes. Phenolic content, although lower for extractions done at 60 oC,
was far from the limit values for discharge, regardless experimental conditions. Given the
high phenolic content the residual water from labdanum extraction by both traditional
processes must be treated before discharge. If separated, phenolic compounds may be
valorized as a by-product.
Em Portugal, crescem espontaneamente espécies de Lavandula da secção
Stoechas Ging. Estas espécies são consideradas Plantas Aromáticas e Medicinais (PAM)
devido à produção de metabolitos secundários com propriedades terapêuticas e
aromáticas. Devido ao seu elevado polimorfismo e capacidade de hibridação na natureza,
torna-se importante o conhecimento e distinção entre as espécies e subespécies. Apesar
de alguns dos constituintes químicos serem compartilhados entre estas espécies, a
presença de outros e respetivas concentrações são exclusivas de cada uma e, por
conseguinte, a sua aplicação e uso também deve ser diferenciado. De forma a contribuir
para a diferenciação entre espécies e subespécies de Lavandula que crescem na região da
Beira Baixa (BB) recorreu-se aos referenciais morfológicos de Portugal e Península
Ibérica. Através da análise destes referenciais, pode-se concluir que existem alguns
parâmetros morfológicos destacados e/ou diferenciadores entre espécies e subespécies,
salientando-se o tamanho do pedúnculo e espiga e respetiva relação, o tamanho das
brácteas inférteis e a forma das brácteas férteis. Neste trabalho, são apresentados os
resultados da observação da maioria dos parâmetros diferenciadores, em 80 plantas
recolhidas na região da BB. De acordo com os resultados, entre as subespécies, a maioria
dos parâmetros são redundantes e comuns, pelo que a análise morfológica externa da
planta não demonstrou ser suficiente para distinguir as subespécies. Considerando a
evolução natural das espécies e polimorfismo, a integração de outros tipos de análises,
como a análise dos constituintes químicos e/ou estudos genéticos, tornam-se importantes
para a diferenciação das subespécies.
Chemical investigations of L. stoechas subsp. luisieri and L. pedunculata essential oils were
analyzed by GC-MS, and the antimicrobial activity was performed against bacteria and fungi isolated
from food sources. The cytotoxicity of the essential oil was performed in NHDF cells using the
MTT method. According to the results, the main compounds of L. stoechas subsp. luisieri essential
oil were trans-α-necrodyl acetate (40.2%), lavandulyl acetate (11%), and trans-α-necrodol (10.4%),
while fenchone (50.5%) and camphor (30.0%) in L. pedunculata essential oil. The antifungal activity
of essential oils was confirmed with MIC values ranging from 1.2 to 18.7 µL/mL; for bacteria, it
ranged from 4.7 to 149.3 µL/mL. Both the Lavandula species tested showed low or equal MIC and
MBC/MFC values for L. stoechas subsp. luisieri essential oil, revealing greater efficacy in antimicrobial
activity. The L. stoechas subsp. luisieri essential oil revealed cytotoxic effects (30 ± 2% of cell viability)
in NHDF cells at all concentrations tested.
The morphology and physiology of plants grown in vitro are regulated by various environmental factors such as light, temperature, humidity and carbon dioxide. Light, in its various parameters such as spectral quality, photon flux and photoperiod, is an important factor among these and generally influences the overall growth and development of plants in vitro. Light sources commonly used for in vitro plant culture are fluorescent lamps, although some research and commercial laboratories also use sodium metal or incandescent metal halide lamps. The spectral of those lamps range from 350 to 750 nm and contain blend lights that differentially affect in vitro plant growth. Recently, light emitting diodes (LEDs) have been developed and are nowadays used as an alternative source of fluorescent light for the development of plants both in greenhouses and in vitro culture rooms. In order to test the influence of these two types of light during multiplication phase, a multiplicity experiment was carried out using two species: a chestnut hybrid (Castanea sativa x C. crenata), clone M2 and the prickled broom (Pterospartum tridentatum (L.) Willk.), Malcata ecotype. Two types of light were tested, "cool white" fluorescent light and LED light with blue and red colors. It was found that LED illumination exerted a significant positive effect on the differentiation of shoots in the case of prickled broom (5.6 instead of 4.9 split shoots under fluorescent light). In the parameters of shoot length, we found that this type of lighting favored the elongation in both species. Regarding the parameters of fresh and dry weight, LED lighting caused a greater effect on the chestnut than on prickled broom. Some physiological parameters (chlorophylls, carotenoids and proteins) were also analyzed and showed to be influenced by the type of light during the development of microplants.
