Antioxidants in Fruit Fractions of Mediterranean Ancient Pear Cultivars.

BACKGROUND: The genetic diversity of Sardinian pear germplasm has received limited attention regarding its chemical composition. Understanding this composition can aid in the setting up of resilient, extensive groves that offer multiple products and ecosystem services. This research aimed at investigating the antioxidant properties and phenolic compounds of ancient pear cultivars grown extensively in Sardinia (Italy); Methods: the cultivars Buttiru, Camusina, Spadona, and Coscia (as a reference) were compared. Fruit samples were manually peeled and cut. Their flesh, peel, core, and peduncle were frozen separately, lyophilized, and milled before being analysed; Results: The content of total phenolics (TotP), total flavonoids (TotF), condensed tannins (CT), and antioxidant capacity in each fruit part varied significantly among the cultivars. The TotP content was high in the peduncle (42.2-58.8 g GAE kg-1 DM) and low in flesh (6.4-17.7 g GAE kg-1 DM); Conclusions: the highest values of antioxidant capacity, TotP, NTP, TotF, and CT were found in the flesh of the cultivar Buttiru and in the peel of the cultivar Camusina. Chlorogenic acid was the major individual phenolic compound in peel, flesh and core, whereas arbutin was mostly present in the peduncle. Results can contribute to revise target exploitations of underutilized ancient pear cultivars.

Subterranean Clover and Sulla as Valuable and Complementary Sources of Bioactive Compounds for Rainfed Mediterranean Farming Systems.

Mediterranean pasture and forage legumes are important components of sustainable production systems. Subterranean clover and sulla represent key species having proven high agronomic value and traits for production and multiple services. Our research investigated the potential of the abovementioned species as a source of phenolic compounds and antioxidants for contributing to support their full exploitation in the fodder, animal welfare, and nutraceutical sectors. Antioxidant capacity, as well as the content of total phenolic compounds and individual phenolic compounds, was determined in subterranean clover and sulla shoots at the vegetative, flower bud, flowering, and seed ripening phenological stages. The antioxidant capacity and the phenolic content were affected significantly by harvest time. In subterranean clover, 10 individual phenolic compounds were detected, and isoflavones were the most abundant (3.19-18.27 mg·g-1 DM). Eleven phenolic compounds were identified in sulla shoots, and chlorogenic acid (0.76-3.43 mg·g-1 DM) and diosmin (3.64-4.94 mg·g-1 DM) were the most represented compounds at the vegetative and flower bud stage. On the basis of our findings, a complementary utilization of both legume species is suggested; this might ensure the exploitation of all phenolic compounds in view of the potential benefits for animal production and health.

Antioxidant Contents in a Mediterranean Population of Plantago lanceolata L. Exploited for Quarry Reclamation Interventions.

Plantago lanceolata L. (plantain) is an interesting multipurpose perennial species whose aerial parts are used in herbal medicine due to its precious phytochemicals and are palatable to animals. Moreover, peculiar traits such as drought tolerance, an extended growth season and a deep root system, make plantain a promising pioneer plant for quarry reclamation based on the use of native species. This study evaluated the effects of different environmental conditions and seasons on the accumulation of the bioactive compounds of its aerial organs. An autochthonous plantain population was grown in three locations in Sardinia (Italy). Leaves, peduncles and inflorescences were collected between October 2020 and July 2021. Phenolic contents and antioxidant capacity were determined. The analysis of the individual phenolic compounds was performed using liquid chromatography. In leaves, the content of total phenolics, antioxidant capacity and total flavonoids were significantly influenced by location and season. Total phenolic content ranged from 65 to 240 g gallic acid equivalent kg-1, whereas total flavonoids were from 16 to about 89 g catechin equivalent kg-1. Neochlorogenic, chlorogenic, cryptochlorogenic acids, verbascoside, diosmin and luteolin were identified in the methanolic extracts of leaves, peduncles and inflorescences. Verbascoside was the main antioxidant isolated from plantain extracts. Results evidenced an increasing accumulation pattern of phenolics from vegetative stage to flowering, followed by a decrement towards the seed ripening as well as site-specific differences with amounts of phenolics even 25% higher for same plantain accession.

Bioactive Compounds from Leaves and Twigs of Guayule Grown in a Mediterranean Environment.

Guayule (Parthenium argentatum) is one of the most promising alternatives to produce natural rubber. As the guayule leaves represent a waste byproduct in the rubber extraction process, their exploitation might contribute to the valorization of the whole plant biomass. The specific aim of our study was to determine the antioxidant capacity and the content of phenolic compounds in leaves and twigs of different guayule lines cultivated in a Mediterranean environment. The antioxidant capacity and the contents of phenolic were affected significantly by guayule accession and harvest time. Overall means in twigs represented about 60% of the corresponding leaf values for antioxidant capacity as DPPH (1,1-diphenyl-2-picrylhydrazyl) and not tannic phenolic and about 55% as ABTS (2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt), total phenolic, tannic phenolic and total flavonoid contents. Five individual phenolic compounds were identified in methanolic extracts of leaves. Neochlorogenic acid (62.5-174.8 mg g-1 DW) and chlorogenic acid (28.6-41.1 mg g-1 DW) were the most abundant phenolic acids. In addition to the compounds quantified in leaves, cynarin was identified only in twigs and for the first time in guayule biomass. Our results indicate that guayule leaves and twigs represent a rich source of antioxidants for potential applications in fodder, nutraceutical and pharmacological sectors.

Phenolic compounds content and antioxidant capacity in cardoon achenes from different head orders.

Cardoon inflorescences (heads) contain achenes, which are used for the production of edible oil and biodiesel but also represent a phenolic source. This research aimed at determining the level of bioactive compounds and antioxidant capacity of cardoon achenes and investigating their qualitative and quantitative variations in achenes harvested from heads having different insertion order on main stem. The head order significantly affected the number of achenes per head and one thousand weight but did not affect the achene values of antioxidant capacity and concentrations of total phenolic (107.7-117.4 g gallic acid equivalent kg-1 dry weight), as well as the concentration of chlorogenic and 3,5-di-O-E-caffeoylquinic acids. Conversely, the absolute amounts of these metabolites differed significantly among head order when referred to a single achene or head. About 75% of their absolute values per cardoon plant were produced by achenes belonging to secondary and tertiary heads.

Antioxidant Sources from Leaves of Russian Dandelion.

Taraxacum kok-saghyz (TKS) is a dandelion species native to Kazakhstan, Uzbekistan and north-west China, considered as a promising alternative source of natural rubber from its roots. The aim of this study was to investigate the possible exploitation of TKS leaves, a rubber byproduct, as a source of phenolic compounds with antioxidant properties for potential applications in forage, nutraceutical and pharmacological fields. Two accessions (TKS016, TKS018) grown under Mediterranean conditions of Sardinia were evaluated at vegetative and flowering stages. The leaves of TKS018 had the highest antioxidant capacity (19.6 mmol trolox equivalent antioxidant capacity 100 g-1 ), total phenolic (106.4 g gallic acid equivalent kg-1 ), tannic phenolics (58.5 g gallic acid equivalent kg-1 ) and total flavonoid contents (22.9 g catechin equivalent kg-1 ). At both phenological stages, TKS016 showed significantly lower values than TKS018 in 1,1-diphenyl-2-picrylhydrazyl (DPPH), total phenolic and tannic phenolics. Six individual molecules were identified, namely chlorogenic, cryptochlorogenic, caffeic, sinapic, chicoric and 3,4-dimethoxycinnamic acids. Chicoric (8.53-10.68 g kg-1 DW) and chlorogenic acids (4.18-7.04 g kg-1 DW) were the most abundant. TKS leaves represent a valuable source of chicoric acid with potential application as antioxidant to be used as herbal medicine and nutrition for production of healthy food/feed.

Polyphenolic composition and antioxidant capacity of legume-based swards are affected by light intensity in a Mediterranean agroforestry system.

BACKGROUND: In Mediterranean grazed woodlands, microclimate changes induced by trees influence the growth and development of the understory, although very little is known about its polyphenolic composition in relation to light intensity. We investigated the bioactive compounds and antioxidant capacity of different legume-based swards and variations as a result of full sunlight and partial shade. The research was carried out in a cork oak agrosilvopastoral system in Sardinia. RESULTS: The highest values of (1,1-diphenyl-2-picrylhydrazyl) (DPPH) reached 7 mmol Trolox equivalent antioxidant capacity 100 g-1 dry weight (DW), total phenolics 67.1 g gallic acid equivalent kg-1 DW and total flavonoids 7.5 g catechin equivalent kg-1 DW. Compared to full sunlight, partial shade reduced DPPH values by 29% and 42%, and the total phenolic content by 23% and 53% in 100% legume mixture and semi-natural pasture, respectively. Twelve phenolic compounds were detected: chlorogenic acid in 80% legume mixture (partial shade) and verbascoside in pure sward of bladder clover (full sunlight) were the most abundant. CONCLUSION: Light intensity significantly affected antioxidant capacity, composition and levels of phenolic compounds. The results of the present study provide new insights into the effects of light intensity on plant secondary metabolites from legume-based swards, highlighting the important functions provided by agroforestry systems. © 2018 Society of Chemical Industry.

The effects of raw propolis on Varroa-infested honey bee (Apis mellifera) workers.

Self-medication plays a major role in the behavioral defense against pathogens and parasites that animals have developed during evolution. The conditions defining this adaptive behavior are: (1) contact with the substance in question must be deliberate; (2) the substance must be detrimental to one or more parasites; (3) the detrimental effect on parasites must lead to increased host fitness. Recent studies have shown that A. mellifera colonies are able to increase resin foraging rates when infested by V. destructor, whereas further investigations are needed for evidence of parasite and host fitness. In order to understand whether Varroa-infested colonies could benefit from increasing levels of resin, we carried out laboratory bioassays to investigate the effects of propolis on the fitness of infested workers. The longevity and energetic stress of adult bees kept in experimental cages and artificially infested with the mite were thus monitored over time. At the same time, in vitro experiments were performed to study the contact effects of crude propolis on Varroa mites. Our results clearly demonstrate the positive effects of raw propolis on the lifespan of Varroa-infested adult bees. A low narcoleptic effect (19-22%) of raw propolis on phoretic mites after 5 h was also observed. In terms of energetic stress, we found no differences between Varroa-free and Varroa-infested bees in terms of the daily sucrose solution demand. Our findings seem to confirm the hypothesis that resin collection and propolis use in the hive represent an example of self-medication behavior in social insects.

Traditional knowledge about plant, animal, and mineral-based remedies to treat cattle, pigs, horses, and other domestic animals in the Mediterranean island of Sardinia.

BACKGROUND: Mediterranean farmers traditionally utilized plants, animals, and minerals sourced locally to treat their animals. Research is needed to understand at what extent such knowledge of domestic animal care still survives and to document such traditions for further developments. METHODS: We carried out our field study to recover ancient ethno-veterinary practices by means of questionnaires and interviews to farmers in rural areas of the Mediterranean island of Sardinia (Italy). Quantitative indices were used to evaluate the distribution and diversity of the acquired information. RESULTS: We report here 98 sources (42 plant taxa, 14 animal-based substances, 15 minerals, and 27 other materials of various origin) emerged from the survey for the care of 41 ailments of cattle, pigs, and horses. Ethno-veterinary treatments, detailed in their formulations and applications, were used against ecto- and endo-parasites, gastrointestinal diseases, heart diseases, viral and bacterial diseases, wounds, sprains, and bruises. CONCLUSION: Our survey can be useful to implement the use of phyto-therapeutics and other remedies of non-herbal origin for diseased animals, and, as elderly farmers held most of the knowledge, it can contribute to the conservation of Mediterranean ethno-veterinary knowledge.

Bioactive compounds and antioxidants from a Mediterranean garland harvested at two stages of maturity.

Chrysanthemum coronarium L. (garland) is an herbaceous plant rich in bioactive compounds. The chemical composition, bioactive compounds and antioxidant properties of a Mediterranean garland population were investigated in different organs at two phenological stages. Antioxidant capacity varied from 7.9 (vegetative) to 14.4 (flowering) mmol Trolox equivalent antioxidant capacity 100 g-1 dry weight (DW). A significant correlation between antioxidant capacity and total phenolics and total flavonoids was found at flowering stage. LC-MS/MS analysis revealed that chlorogenic acid reached a maximum of 4.7 µg g-1 DW in leaves; flowers were high in luteolin (2.37 µg g-1 DW), whereas leaves showed a remarkable content of rutin (1.78 µg g-1 DW). Results highlight differences in bioactive compound levels and antioxidant capacity related to plant stages and organs. This research provides new insights into antioxidant activities and chemistry of garland, in view of its exploitation in areas of fodder resources, functional foods and natural antioxidants.

Condensed tannin accumulation and nitrogen fixation potential of Onobrychis viciifolia Scop. grown in a Mediterranean environment.

BACKGROUND: Sainfoin (Onobrychis viciifolia Scop.) is a forage legume found in temperate areas but is less widespread in Mediterranean environments. Compared with other perennial legumes, it has the advantage of containing condensed tannins (CT) that can be important for their implications on ruminant nutrition and health. Data on nitrogen (N) fixation by sainfoin in the literature originate from very different environments and only a few field data are available, so it is important to improve knowledge on the N fixation potential of this species, particularly under a Mediterranean climate. Here the accumulation pattern of polyphenolic compounds (total, non-tannic polyphenols and CT) and the N fixation potential of sainfoin were studied in order to contribute to its valorisation for sustainable farming management in Mediterranean environments. RESULTS: CT concentrations were always in the range considered beneficial for animals, not exceeding 50 g delphinidin equivalent kg⁻¹ dry matter (DM). The regression of aerial fixed N on aerial DM showed a relationship of 22 kg fixed N t⁻¹ aerial DM in a Mediterranean environment. CONCLUSION: A wider exploitation of sainfoin is suggested for production under rain-fed conditions, thus enlarging the limited set of available perennial legumes suitable for Mediterranean environments.

Correlations between phenolic content and antioxidant properties in twenty-four plant species of traditional ethnoveterinary use in the Mediterranean area.

CONTEXT: Scientific information on antioxidant properties and phenolic content of less widely used plants can be useful. Therefore, the assessment of such properties remains an interesting and useful task, particularly for finding new sources for natural antioxidants, functional foods, and nutraceuticals. OBJECTIVE: As knowledge about antioxidant properties and phenolic content of many plant species used as traditional plant remedies is limited, we determined in vitro the total antioxidant activity and the phenolic content of several plant species traditionally used for ethnoveterinary practices. MATERIALS AND METHODS: For 24 extracts (70% acetone) from wild and cultivated plant species traditionally used for health care of animals we determined the Trolox equivalent antioxidant capacity (TEAC) by the two assays 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS). The phenolic content was determined by the Folin Ciocalteu method. RESULTS: Total phenolics, calculated as gallic acid equivalent (GAE), showed variation ranging from 3.18 (Allium sativum L. (Liliaceae)) to 147.68 (Pistacia lentiscus L. (Anacardiaceae)) mgGAE/g dry weight (DW). High TEAC values corresponded to high phenolic content, while plants with low antioxidant activity exhibited low total phenolic content. The TEAC determined through each assay and total phenolic content were positively correlated, R² = 0.9152 and R² = 0.8896, respectively, for DPPH and ABTS assay. DISCUSSION AND CONCLUSION: These findings suggest that phenolic content could be used as an indicator of antioxidant properties. The results of this study encourage investigations on Mediterranean plant species as sources of antioxidants.

The dynamics of phenolic concentration in some pasture species and implications for animal husbandry.

BACKGROUND: Although secondary metabolites have often been studied considering their primary role as plant-defensive and their effect on consumers detrimental, their effects are usually dose-dependent, so it is important to consider their content at all phenological phases and in different plant organs. In this study the content of total phenolics (TotP), non-tannic phenolics (NTP) and proanthocyanidins (PA) was determined in natural populations of pasture species at defined phenological phases and in different plant organs and also in pathogen-infected plants. RESULTS: Variation in TotP, NTP and PA content was observed in all species, phenological phases and plant organs. Leaf blades were the organs with the highest content in all species. The content of all examined compounds increased in infected leaves, reaching the maximum when 20% of plant tissues were attacked and decreasing at higher infection levels. CONCLUSION: Delphinidin was found as an appropriate standard related to the PA structure of each plant species. PA concentrations were always in the range considered beneficial for animals, not exceeding 60 g delphinidin equivalent kg(-1) dry matter. The Folin-Ciocalteu and butanol/HCl/Fe(3+) assays remain the most practical methods for screening large numbers of different plant species for TotP and PA.