Changes in the content of anthocyanins, flavonols, and antioxidant activity in Fragaria ananassa var. Camarosa fruits under traditional and organic fertilization

Design of Microbial Consortia Based on Arbuscular Mycorrhizal Fungi, Yeasts, and Bacteria to Improve the Biochemical, Nutritional, and Physiological Status of Strawberry Plants Growing under Water Deficits

Drought affects several plant physiological characteristics such as photosynthesis, carbon metabolism, and chlorophyll content, causing hormonal and nutritional imbalances and reducing nutrient uptake and transport, which inhibit growth and development. The use of bioinoculants based on plant growth-promoting microorganisms such as plant growth-promoting rhizobacteria (PGPR), yeasts, and arbuscular mycorrhizal fungi (AMF) has been proposed as an alternative to help plants tolerate drought. However, most studies have been based on the use of a single type of microorganism, while consortia studies have been scarcely performed. Therefore, the aim of this study was to evaluate different combinations of three PGPR, three AMF, and three yeasts with plant growth-promoting attributes to improve the biochemical, nutritional, and physiological behavior of strawberry plants growing under severe drought. The results showed that the growth and physiological attributes of the non-inoculated plants were significantly reduced by drought. In contrast, plants inoculated with the association of the fungus Claroideoglomus claroideum, the yeast Naganishia albida, and the rhizobacterium Burkholderia caledonica showed a stronger improvement in tolerance to drought. High biomass, relative water content, fruit number, photosynthetic rate, transpiration, stomatal conductance, quantum yield of photosystem II, N concentration, P concentration, K concentration, antioxidant activities, and chlorophyll contents were significantly improved in inoculated plants by up to 16.6%, 12.4%, 81.2%, 80%, 79.4%, 71.0%, 17.8%, 8.3%, 6.6%, 57.3%, 41%, and 22.5%, respectively, compared to stressed non-inoculated plants. Moreover, decreased malondialdehyde levels by up to 32% were registered. Our results demonstrate the feasibility of maximizing the effects of inoculation with beneficial rhizosphere microorganisms based on the prospect of more efficient combinations among different microbial groups, which is of interest to develop bioinoculants oriented to increase the growth of specific plant species in a global scenario of increasing drought stress.

Management of Rhizosphere Microbiota and Plant Production under Drought Stress: A Comprehensive Review

Drought generates a complex scenario worldwide in which agriculture should urgently be reframed from an integrative point of view. It includes the search for new water resources and the use of tolerant crops and genotypes, improved irrigation systems, and other less explored alternatives that are very important, such as biotechnological tools that may increase the water use efficiency. Currently, a large body of evidence highlights the role of specific strains in the main microbial rhizosphere groups (arbuscular mycorrhizal fungi, yeasts, and bacteria) on increasing the drought tolerance of their host plants through diverse plant growth-promoting (PGP) characteristics. With this background, it is possible to suggest that the joint use of distinct PGP microbes could produce positive interactions or additive beneficial effects on their host plants if their co-inoculation does not generate antagonistic responses. To date, such effects have only been partially analyzed by using single omics tools, such as genomics, metabolomics, or proteomics. However, there is a gap of information in the use of multi-omics approaches to detect interactions between PGP and host plants. This approach must be the next scale-jump in the study of the interaction of soil–plant–microorganism. In this review, we analyzed the constraints posed by drought in the framework of an increasing global demand for plant production, integrating the important role played by the rhizosphere biota as a PGP agent. Using multi-omics approaches to understand in depth the processes that occur in plants in the presence of microorganisms can allow us to modulate their combined use and drive it to increase crop yields, improving production processes to attend the growing global demand for food.

Advanced Analytical Approaches for the Analysis of Polyphenols in Plants Matrices—A Review

Phenolic compounds are plants’ bioactive metabolites that have been studied for their ability to confer extensive benefits to human health. As currently there is an increased interest in natural compounds identification and characterization, new analytical methods based on advanced technologies have been developed. This paper summarizes current advances in the state of the art for polyphenols identification and quantification. Analytical techniques ranging from high-pressure liquid chromatography to hyphenated spectrometric methods are discussed. The topic of high-resolution mass spectrometry, from targeted quantification to untargeted comprehensive chemical profiling, is particularly addressed. Structure elucidation is one of the important steps for natural products research. Mass spectral data handling approaches, including acquisition mode selection, accurate mass measurements, elemental composition, mass spectral library search algorithms and structure confirmation through mass fragmentation pathways, are discussed.

Effect of Breed and Finishing Diet on Growth Parameters and Carcass Quality Characteristics of Navarre Autochthonous Foals

Simple Summary

Nowadays, populations are more health conscious and pay more attention to the environmental impact of their food choices. In this context, horsemeat plays a significant role, since it is claimed as “dietetic” meat by researchers. In addition, equine meat production is arousing interest due to its relevant environmental potential. However, several factors have been shown to affect carcass and horsemeat quality. In this sense, our study evaluates the impact of breed (Jaca Navarra and Burguete) and type of finishing diet (conventional diet and silage with organic feed) on carcass traits from Navarre endangered foals. Moreover, considering the limited information about Jaca Navarra foals from a meat production perspective, this work represents a starting point to improve the handling of these equids. Data reported Burguete predominance in growth and in most carcass traits, confirming its remarkable aptitude as a meat producer. However, finishing diet showed to improve Jaca Navarra features. A conventional diet showed a positive effect on the majority of variables studied in comparison with the other diet. Thus, breed and the type of finishing diet demonstrated a crucial role in the improvement and optimization of the majority of productive and carcass traits of these endangered equids.

Abstract

This research was conducted to study the effect of breed, Jaca Navarra (JN) vs. Burguete (BU), and finishing diet, conventional concentrate—diet 1 vs. silage and organic feed diet 2—on growth parameters and carcass characteristics from forty-six foals. Parameters as live weight (LW), average daily gain (ADG), body condition score (BCS), and fat depots were monitoring. In addition, the carcass parameters assessed were: carcass weight (CW), conformation, degree of fatness, morphology, and pH. Moreover, hindquarters of the left-half carcasses were sectioned in the main commercial primal cuts of leg. Results showed a clear “breed effect” in favor of BU foals, recording the highest productive values and carcass traits compared with JN foals. On the other hand, finishing diet contributed to improving the productive and carcass features of JN foals. In particular, diet 1 showed to affect positively the features analyzed compared with diet 2. Nevertheless, the meat primal cuts resulted in being unaffected by the breed and diet effects (except for knuckle), obtaining similar values among the groups of animals.

Influence of Profiles and Concentrations of Phenolic Compounds in the Coloration and Antioxidant Properties of Gaultheria poeppigii Fruits from Southern Chile

Chaura (Gaultheria poeppigii) is a plant species native from Southern Chile, which produces a berry fruit with potential beneficial health effects due to its content of phenolic compounds. The qualitative and quantitative determination of the phenolic compounds from fruits of different colored genotypes (white-, pink- and red-colored) collected from the Osorno volcano and the Conguillío National Park (CNP) in southern Chile were analyzed by mass spectrometry (HPLC-DAD-ESI-MS/MS) and HPLC-DAD, respectively. The total content of phenolic compounds was evaluated by the Folin-Ciocalteu method, and its antioxidant activity by the CUPRAC, TEAC and DPPH methods. Four anthocyanins were detected, with glycosylated derivatives of delphinidin and cyanidin being the most abundant. Fruits with more coloration had higher anthocyanin concentrations. Six flavonols were detected, with quercetin derivatives being the most abundant. The highest concentration of total flavonols reached 0.41 mg g^-1 in red colored fruits. The profiles of phenolic compounds showed differences between fruits depending on both the color and the area of collection. Finally, it would be interesting to evaluate the genetic profiles of chaura to determine whether this variation in phenolics and colorations is dependent on the geographical location or dependent on the genotype of the plant.

Antioxidant Responses of Phenolic Compounds and Immobilization of Copper in Imperata Cylindrica, a Plant with Potential Use for Bioremediation of Cu Contaminated Environments

This work examined the capability of Imperata cylindrica to respond, tolerate and accumulate Cu when growing at high Cu concentration (300 mg kg-1 of substrate) at different times of exposure (2, 14 and 21 days). The Cu accumulation in plants was examined by atomic absorption spectroscopy (AAS) and Cu localized by Scanning Electron Microscopy-Energy Dispersive X-Ray spectroscopy. Additionally, the phenolic compound identifications and concentrations were determined using liquid chromatography coupled to mass spectrometry. Our results showed that root biomass decreased significantly at high Cu levels, with a greater decrease at 21 days (39.8% less biomass in comparison to control). The root showed 328 mg Cu kg-1 dry weight at 21 days of exposure to Cu, being the tissue that accumulates most of the Cu. Lipid peroxidation was a clear indicator of Cu stress, principally in shoots. The exposure to Cu significantly increased the synthesis of phenolic compounds in shoots of plants exposed 21 days to Cu, where 5-caffeoylquinic acid reached the highest concentrations. Our results support that I. cylindrica is a Cu accumulator plant in root organs with a medium level of accumulation (between 200-600 mg Cu kg-1 biomass), which can tolerate the exposure to high Cu levels by means of increasing the synthesis of phenolic compound in shoots, suggesting a potential use as phytoremediation tool in Cu polluted environments.

Determination of Polyphenols Using Liquid Chromatography-Tandem Mass Spectrometry Technique (LC-MS/MS): A Review

In recent years, the consumption of polyphenols has been increasing, largely due to its beneficial effects on health. They are present in a wide variety of foods, but their extraction and characterization are complicated since they are mostly in complex matrices. For this reason, the use of selective, sensitive, and versatile analytical techniques such as liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) is necessary. In this review, the most relevant studies of the last years regarding the analysis of polyphenols in different matrices by comprehensive LC–MS/MS are discussed. Relevant steps such as extraction, sample purification, and chromatographic analysis methods are emphasized. In particular, the following methodological aspects are discussed: (a) the proper selection of the extraction technique, (b) the extraction and elution solvents, (c) the purification step, (d) the selection of both stationary and mobile phases for the chromatographic separation of compounds, and (e) the different conditions for mass spectrometry. Overall, this review presents the data from the most recent studies, in a comprehensive way, thus providing and simplifying the information of the great variety of works that exist in the literature on this wide topic.