Search results

Dissertação apresentada à Escola Superior Agrária do Instituto Politécnico de Castelo Branco para obtenção do Grau de Mestre em Inovação e Qualidade na Produção Alimentar

Dissertação apresentada à Escola Superior Agrária do Instituto Politécnico de Castelo Branco para obtenção do Grau de Mestre em Inovação e Qualidade na Produção Alimentar

Tese apresentada à Escola Superior Agrária do Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Inovação e Qualidade na Produção Alimentar.

Distilled spirits are usually made from fermented sugar-based materials, such as wines or fermented fruits, but other products can be used, namely berries or honey. In this work, an evaluation of honey spirits is done based on its physicochemical and sensory characteristics. Fourteen honey spirit samples of different brands of honey spirit were purchased at the market and from artisan Portuguese producers. Several analytical determinations, namely alcoholic strength, dry matter, density, total acidity, chromatic characteristics, methanol, acetaldehyde, ethyl acetate and higher alcohols were done to characterize all samples. The results pointed out several differences in physicochemical composition of samples. In general, these drinks are characterized by an alcohol strength between 37.4% and 53.0% and a low methanol content, quite null for most samples. Samples with higher ethanol content corresponded to the artisanal samples. Significant differences (p < 0.05) were also observed in the volatile composition and chromatic characteristics suggesting different production technologies. A first list of sensory attributes was obtained for this beverage. Therefore, further research must be done in order to characterize this spirit drink, which has gained market value.

: 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.

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.

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.

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.

Main conclusion: The combination of genotypic selection, targeted and improved cultivation, and processing techniques for specific applications gives C. ladanifer the potential to be used as a valuable resource in Mediterranean areas with poor agronomic advantages. Cistus ladanifer (rockrose) is a perennial shrub, well adapted to the Mediterranean climate and possibly to upcoming environmental changes. As a sequence to a thorough review on taxonomic, morphological, chemical and competitive aspects of C. ladanifer, the research team focuses here on the economic potential of C. ladanifer: from production to applications, highlighting also known biological activities of extracts and their compounds. The use of this natural resource may be a viable solution for poor and contaminated soils with no need for large agricultural techniques, because this species is highly resistant to pests, diseases and extreme environmental factors. In addition, this species reveals interesting aptitudes that can be applied to food, pharmaceutical, phytochemical and biofuel industries. The final synthesis highlights research lines toward the exploitation of this neglected resource, such as selection of plant lines for specific applications and development of agronomic and processing techniques.

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.

Labdanum resin from Cistus ladanifer L. (Cistaceae) is an abundant natural resource in the Iberian Peninsula worth being explored in a sustainable manner. It is already used in the cosmetic industry; mainly by the fragrances/perfumery sector. However, given the highest market share and traditional uses, labdanum resin also has the potential to be used and valued as a cosmetic ingredient for skincare. Aiming to evaluate this potential, labdanum methanolic absolute and fractions purified by column chromatography were characterized by UPLC-DAD-ESI-MS and then evaluated for UVprotection, antioxidant, anti-elastase, anti-inflammatory, and antimicrobial activities. Labdanum absolute represented ~70% of the resin; diterpenoid and flavonoid fractions represented ~75% and 15% of the absolute, respectively. Labdane-type diterpenoids and methylated flavonoids were the main compounds in labdanum absolute and in diterpenoid and flavonoid fractions, respectively. Labdanum absolute showed a spectrophotometric sun protection factor (SPF) near 5, which is mainly due to flavonoids, as the flavonoids’ SPF was 13. Low antioxidant activity was observed, with ABTS radical scavenging being the most significant (0.142 ± 0.017, 0.379 ± 0.039 and 0.010 ± 0.003 mgTE/mgExt, for the absolute and flavonoid and terpene fractions, respectively). Anti-aging and anti-inflammatory activity are reported here for the first time, by the inhibition of elastase activity (22% and 13%, by absolute and flavonoid extract at 1 mg/mL), and by the inhibition of nitric oxide production in LPS-induced RAW 264.7 cells (84% to 98%, at 15 µg/mL extracts, flavonoid fraction the most active), respectively. Antimicrobial activity, against relevant skin and cosmetic product microorganisms, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Escherichia coli, revealed that only S. aureus was susceptible to labdanum absolute (MIC: 1.2 mg/mL) and its fractions (MIC: <0.3 mg/mL). In conclusion, labdanum resin showed potential to be used in sunscreen cosmetics, anti-inflammatory skincare cosmeceuticals or medicines but has low potential as a cosmetic product preservative given the low antioxidant and low-spectrum antimicrobial activities.

Cistus ladanifer is a persistent, abundant and widespread underexplored resource in the Iberian Peninsula. The seeds have been used as food for centuries, although their nutritional value and potential as food ingredients have not been exploited until now. In this study seeds from natural shrubland were collected three times during summer for two consecutive years. Analytical evaluation of the macronutrient content, fatty acids, and mineral composition was performed. Regarding the macronutrients, seeds showed a carbohydrate content of 46.1 ± 1.6%, a fibre content of 20.9 ± 1.4%, a protein content of 16.2 ± 0.4%, a lipid content of 13.0 ± 1.1%, and an ash content of 3.87 ± 0.16%. The fatty acids were found to be mostly unsaturated (74.05 ± 0.59%). Potassium was the most abundant mineral (975 ± 53 mg/100 g) followed by phosphorous, magnesium and calcium. In conclusion, several nutrient-related label claims may be used for C. ladanifer seeds as food ingredient. Compared to common cereals, nuts and seeds, C. ladanifer seeds are close to flax and chia seeds in relation to nutritional composition, and to pine nuts in relation to mineral composition.