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Vol. I : Olericultura, plantas ornamentais, plantas aromáticas e medicinais. - 634 p
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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.
Medicinal plants have been used since the earliest documented history around the
world, as an available and inexpensive therapeutic resource. Plant based bioactive
elements play eminent biological roles as antioxidant, anti-inflammatory and
antiproliferative agents. It is proved that naturally occurring antioxidants in
ethnomedicinal plants are effective in treating various types of diseases.
However, herbal medicine, without any knowledge of their toxicological profile,
target organ, and safe dose, is one of the biggest problems of recent health care systems.
Any drug or herbal formula which is intended to be used in humans must first be tested
in suitable experimental in vitro or animal models in order to evaluate its safety.
Therefore, it is of interest to evaluate the toxicity of plant extracts to enhance their value
for the pharmaceutical and cosmetic industries. Six extracts of plants
produced/endogenous in Portugal: Cistus ladanifer, Thymbra capitata, Helichrysum
italicum, Cupressus lusitanica, Ocimum basilicum and Matricaria chamomilla were used
in order to assess their reproductive toxicity by evaluating the viability of sperm when in
contact with the extracts. Hydrolates for each plant were obtained by hydrodistillation of
aerial parts. The chemical composition of the hydrolates was determined by GC-MS (gas
chromatography mass spectrometry).
Reproductive toxicity was assessed by exposing cryopreserved bovine semen to
six different concentrations of each hydrolate (0.2%-0.002% v/v). Methyl
methanesulfonate (MMS) was used (0.22nM) as positive control of sperm toxicity. After
incubation, sperm viability was determined for each concentration by staining with eosinnigrosin
and counting the number of viable and dead spermatozoa (spz) in a total of 200
spz.
The results show that the hydrolates in test do not compromise sperm viability for
all tested concentrations (>25%) when compared with negative control (34%) and in fact,
M. chamomilla seems to promote sperm viability (39%) at the highest tested
concentration.
These results indicate that the extracts at the concentrations used do not seem to
have a toxic effect on this evaluated target.
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.
Vol. IV - Fruticultura viticultura. - 493 p., gráficos. - (Actas de horticultura)
Vol. I - Geral horticultura. - 485 p., gráficos. - (Actas de horticultura)
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Bibliografia : f. 34
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Dissertação de mestrado em Instrumentos e Técnicas de Apoio ao Desenvolvimento Rural apresentada na Universidade de Trás-os-Montes e Alto Douro
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