Perennially young: seed production and quality in controlled and natural populations of Cistus albidus reveal compensatory mechanisms that prevent senescence in terms of seed yield and viability.

The question of whether or not perennial plants senesce at the organism level remains unresolved. The aim of this study was to unravel whether or not plant age can influence the production and composition of seeds. Flower and seed production was examined in 3-, 8-, and 13-year-old Cistus albidus plants growing in experimental plots corresponding to the F2, F1, and F0 generations of the same population. Furthermore, the phytohormone, fatty acid, and vitamin E content of the seeds was evaluated, and their viability was examined. Whether or not age-related differences in seed quality were observed in a natural population in the Montserrat Mountains (NE Spain) was also tested. The results indicate that under controlled conditions, the oldest plants not only produced fewer flowers, but also had higher rates of embryo abortion in mature seeds. However, germination capacity was not negatively affected by plant ageing. Seeds of the oldest plants contained significantly higher salicylic acid, jasmonic acid, and vitamin E levels compared with those from younger plants. Despite vigour (in terms of plant growth) being severely reduced due to harsh environmental conditions in the natural population, the oldest individuals produced seeds with no decline in viability. Seed biomass was instead positively correlated with seed viability. In conclusion, increased plant size may explain the loss of seed viability in the experimental field, but older smaller individuals in natural populations can escape senescence in terms of seed viability loss.

Chemical composition and potential antioxidant, anti-inflammatory, and analgesic efficacy of Cistus albidus L.

This study aims to assess the chemical composition of the aqueous extract of Cistus albidus L. leaves, as well as the potential of aqueous and hydroethanol extracts of the leaves and seeds as analgesic, anti--inflammatory, and antioxidant agents. The contents of phenolics and inorganic constituents were determined in C. albidus seeds and leaves; antioxidant capacity was assessed by 3 complementary and diverse tests. The carrageenan-induced paw edema technique was used to investigate the anti-inflammatory effect in vivo, and albumin denaturation to evaluate the anti-inflammatory effect in vitro. The acetic acid-induced contortion test, the tail-flick test, and the plantar test were used to assess the analgesic effi cacy in vivo. Chemical analysis was performed by UPLC-MS/MS to quantify several phenolic compounds including catechin (1,627.6 mg kg-1), quercitrin (1,235.8 mg kg-1) and gallic acid (628. 2 mg kg-1). The ICP analysis revealed that potassium and calcium were the main inorganic components in the seeds and leaves of C. albidus. The hydroethanolic extract of the leaves showed the highest content of polyphenols/flavonoids, whereas the highest value of proantho cyanidins was detected in the aqueous extract of the seeds. All extracts showed potent antioxidant activity related to different phenolic compounds (quercetin, gallic acid, astragalin, catechin, and rutin). The aqueous extract of the leaves strongly inhibited paw edema (76.1 %) after 6 h of treatment and showed maximal inhibition of protein denaturation (191.0 µg mL-1 for 50 % inhibition) and analgesic activity in different nociceptive models. The presented data reveal that C. albidus extracts potentially show antioxidant, anti-inflammatory, and analgesic activities that could confirm the traditional use of this plant.

Chemical profiling of volatile compounds of the essential oil of grey-leaved rockrose (Cistus albidus L.) and its antioxidant, anti-inflammatory, antibacterial, antifungal, and anticancer activity in vitro and in silico.

Cistus albidus: L., also known as Grey-leaved rockrose and locally addressed as stab or tûzzâla lbîda, is a plant species with a well-established reputation for its health-promoting properties and traditional use for the treatment of various diseases. This research delves into exploring the essential oil extracted from the aerial components of Cistus albidus (referred to as CAEO), aiming to comprehend its properties concerning antioxidation, anti-inflammation, antimicrobial efficacy, and cytotoxicity. Firstly, a comprehensive analysis of CAEO's chemical composition was performed through Gas Chromatography-Mass Spectrometry (GC-MS). Subsequently, four complementary assays were conducted to assess its antioxidant potential, including DPPH scavenging, ß-carotene bleaching, ABTS scavenging, and total antioxidant capacity assays. The investigation delved into the anti-inflammatory properties via the 5-lipoxygenase assay and the antimicrobial effects of CAEO against various bacterial and fungal strains. Additionally, the research investigated the cytotoxic effects of CAEO on two human breast cancer subtypes, namely, MCF-7 and MDA-MB-231. Chemical analysis revealed camphene as the major compound, comprising 39.21% of the composition, followed by α-pinene (19.01%), bornyl acetate (18.32%), tricyclene (6.86%), and melonal (5.44%). Notably, CAEO exhibited robust antioxidant activity, as demonstrated by the low IC50 values in DPPH (153.92 ± 4.30 µg/mL) and ß-carotene (95.25 ± 3.75 µg/mL) assays, indicating its ability to counteract oxidative damage. The ABTS assay and the total antioxidant capacity assay also confirmed the potent antioxidant potential with IC50 values of 120.51 ± 3.33 TE µmol/mL and 458.25 ± 3.67 µg AAE/mg, respectively. In terms of anti-inflammatory activity, CAEO displayed a substantial lipoxygenase inhibition at 0.5 mg/mL. Its antimicrobial properties were broad-spectrum, although some resistance was observed in the case of Escherichia coli and Staphylococcus aureus. CAEO exhibited significant dose-dependent inhibitory effects on tumor cell lines in vitro. Additionally, computational analyses were carried out to appraise the physicochemical characteristics, drug-likeness, and pharmacokinetic properties of CAEO's constituent molecules, while the toxicity was assessed using the Protox II web server.

Phytochemical profiles and evaluation of the biological potential of ethyl acetate and n-butanol fractions of the aerial parts of Cistus albidus L.

The phytochemical profiles of the ethyl acetate (EAFCA) and n-butanol (BFCA) fractions of the aerial parts of Cistus albidus L., were characterised by a developed LC-ESI-MS/MS method, using 53 fingerprint phytochemicals, revealing the presence of 26 and 22 compounds, respectively with quinic acid, gallic acid, protocatechuic acid, catechin, gentisic acid, tannic acid, ellagic acid, quercitrin, astragalin as the major compounds of the EAFCA, in very higher amounts than in the BFCA. The antioxidant activity was evaluated using six methods (DPPH•, ABTS•+, GOR•, CUPRAC, FRAP and Phenanthroline). In agreement with its highest polyphenolic content (430.12 ± 1.02 µg GAE/mg of extract) and largest amounts of identified polyphenolics, the EAFCA exhibited a higher antioxidant activity than the BFCA. Additionally, the EAFCA showed the highest acetylcholinesterase (AChE) inhibition (IC50 of 25.1 ± 2.58 µg/mL). Moreover, both EAFCA and BFCA demonstrated high photoprotective activity, with sun protection factor (SPF) values of 36.49 and 36.52, respectively.

Leaf Orientation as Part of the Leaf Developmental Program in the Semi-Deciduous Shrub, Cistus albidus L.: Diurnal, Positional, and Photoprotective Effects During Winter.

Mediterranean ecosystems harbor a very important part of Earth's biodiversity, and they are a conservation priority due to the effects of global change. Here, we examined the performance of the semi-deciduous shrub Cistus albidus under Mediterranean conditions during winter, including changes in leaf angle governed by diurnal, seasonal, and positional effects and their relationship with winter photoinhibition and photoprotection. We found marked diurnal variations in leaf angle during the day in autumn, which disappeared as the photoperiod shortened during winter due to a progressive decrease in the predawn leaf angle from November to January. During this period, auxin contents decreased, while those of melatonin increased, and the F v/F m ratio, chlorophyll, and tocopherol contents kept unaltered, thus indicating the absence of photoinhibitory damage. A marked decrease in the leaf angle toward the shoot apex occurred during winter, which was associated with slightly higher F v/F m ratios. An analysis of the inter-individual variability and sun orientation effects on leaf movements in a population growing in the Montserrat mountains revealed a very marked variability of 46.8% in the leaf angle, while F v/F m ratio showed a variation of 7.5% only. West orientation, which was associated with reduced leaf temperatures, but with no differences in the photosynthetic photon flux density, led to enhanced tocopherol contents, while leaf angle, F v/F m ratio, chlorophyll, auxin, and melatonin contents kept unaltered. It is concluded that (1) C. albidus has very effective and fine-regulated photoprotection mechanisms, including an adequate orientation of decussate leaves as part of the developmental program, (2) leaf angle is modulated on a diurnal and seasonal basis, thus contributing to prevent photoinhibition as a first line of defense, and (3) enhanced tocopherol contents help withstand combined high light with low temperature stress in C. albidus growing at high elevation.