Salt stress perception and metabolic regulation network analysis of a marine probiotic Meyerozyma guilliermondii GXDK6

Introduction

Extremely salt-tolerant microorganisms play an important role in the development of functional metabolites or drug molecules.

Methods

In this work, the salt stress perception and metabolic regulation network of a marine probiotic Meyerozyma guilliermondii GXDK6 were investigated using integrative omics technology.

Results

Results indicated that GXDK6 could accept the salt stress signals from signal transduction proteins (e.g., phosphorelay intermediate protein YPD1), thereby contributing to regulating the differential expression of its relevant genes (e.g., CTT1, SOD) and proteins (e.g., catalase, superoxide dismutase) in response to salt stress, and increasing the salt-tolerant viability of GXDK6. Omics data also suggested that the transcription (e.g., SMD2), translation (e.g., MRPL1), and protein synthesis and processing (e.g., inner membrane protein OXA1) of upregulated RNAs may contribute to increasing the salt-tolerant survivability of GXDK6 by improving protein transport activity (e.g., Small nuclear ribonucleoprotein Sm D2), anti-apoptotic ability (e.g., 54S ribosomal protein L1), and antioxidant activity (e.g., superoxide dismutase). Moreover, up to 65.9% of the differentially expressed genes/proteins could stimulate GXDK6 to biosynthesize many salt tolerant-related metabolites (e.g., β-alanine, D-mannose) and drug molecules (e.g., deoxyspergualin, calcitriol), and were involved in the metabolic regulation of GXDK6 under high NaCl stress.

Discussion

This study provided new insights into the exploration of novel functional products and/or drugs from extremely salt-tolerant microorganisms.Graphical Abstract.

[Cow colostrum: component composition, biological properties and application practice]

Bovine colostrum (ВС) has a high biological value, which allows it to be used for the development of new functional products. The aim of the study was to assess the possibility of using BC for the prevention and treatment of infectious and non-infectious diseases. Material and methods. The search for scientific information on the study of the component composition, immunobiological properties and the use of BC in clinical practice was carried out using the databases of the RSCI, CyberLeninka, ScienceDirect, PubMed. Results. The macro- and micronutrient composition of BC is presented, its changes over time from the moment of calving are described. A comparative analysis of the content of various components in milk and colostrum is presented. A detailed list of antimicrobial factors that increase nonspecific resistance and provide immunocorrective, antimicrobial and anti-inflammatory effects is submitted. The possibility of using BC in clinical practice as a part of complex therapy in the treatment of various infectious diseases, including severe acute respiratory syndrome caused by the new coronavirus infe ction SARS-CoV-2, as well as in cardiovascular diseases, allergies, autoimmune and oncological diseases, has been demonstrated. Conclusion. According to the literature, BC has a high safety profile and is applicable to all age groups of the population. Given the wide range of biological activity of BC components, a promising area of scientific research is the development of the products for therapeutic and prophylactic purposes, including dietary supplements, based on its ingredients, which have the desired properties for correcting the immune status, preventing non-communicable and infectious diseases, as well as for prevention of occupational diseases among persons working in harmful working conditions.

Bioactive Compounds from Leaf Vegetables as Preservatives

Trends toward a healthier diet are increasing attention to clean-label products. This has led to the search for new ingredients that avoid the use of chemical additives. Food industries are responding to these demands by incorporating natural preservatives into their products, which consumers perceive as healthy. Leafy vegetables would fit this strategy since they are common components of the diet and are associated with beneficial health effects. The objective of this chapter is to offer an overview of the large number of bioactive compounds (phenolic acids, flavonoids, anthocyanins, glucosinolates, and sulfur compounds) present in these plants, which would be responsible for their activity as potential preservatives. Its incorporation into food would improve the quality and extend the shelf life by reducing oxidative processes and inhibiting or retarding the microbial growth that occurs during processing and storage without reducing the organoleptic characteristics of the product.

Nuts as a Dietary Enrichment with Selected Minerals-Content Assessment Supported by Chemometric Analysis

Nuts used as a snack and meal accompaniment supply plant protein and fatty acids that are beneficial for human health; however, they can also provide minerals. The aim of this study was to determine the content of selected elements that are often deficient in the diet (calcium, potassium, magnesium, selenium, and zinc) in nuts and determine whether they can be used to supplement deficiencies in the diet. In this study, we analyzed 10 types of nuts (n = 120 samples) that are consumed and available for sale in Poland. The content of calcium, magnesium, selenium, and zinc was determined by the atomic absorption spectrometry method, and flame atomic emission spectrometry was used for determination of potassium contents. The highest median calcium content was found in almonds (2825.8 mg/kg), the highest potassium content in pistachio nuts (15,730.5 mg/kg), the highest magnesium and selenium contents in Brazil nuts (10,509.2 mg/kg and 4348.7 μg/kg, respectively), and the highest zinc content in pine nuts (72.4 mg/kg). All the tested nuts are a source of magnesium, eight types of tested nuts are a source of potassium, six nut types are a source of zinc, and four nut types are a source of selenium; however, among the tested nuts, only almonds can be considered a source of calcium. Moreover, we found that selected chemometric methods can be useful in the classification of nuts. The studied nuts are valuable products that can be used to supplement the diet with selected minerals and can therefore be labelled as functional products crucial for disease prevention.

[Pre-clinical studies of cold exposure to evaluate the efficiency and functionality of a specialized product]

Strengthening the adaptive capabilities of the human body during cold exposure is one of the conceptual elements of solving the problem of the well-being of the population of the northern regions of Russia. The aim of the work was to determine the dynamic performance, endurance and to study the morphological parameters of the rat tracheal mucosa against the background of the consumption of functional confectionery products containing the juice of Chinese lemongrass berries (Schisandra chinensis) and dry extract of eleutherococcus (Eleutherococcus) in regular exposure to cold. Material and methods. The study was carried out on albino rats weighing 190±10 g. Functional confectionery were not introduced into the diet of rats of the 1st group. Rats of the 2nd and 3rd experimental groups were fed 1 g of marmalade and 1 g of caramel three times a day. Rats of the 3rd group were additionally regularly exposed to cold in the Memmert climate chamber (Germany) for an hour three times a day for 30 days. The groups were formed according to the principle of analogs, using body weight as a criterion (the difference in average weight did not exceed 10%), while each group had the same number of males and females. The physical performance was evaluated by the swimming time of the albino rats until complete exhaustion. The endurance to static load was determined by the retention time on a vertical metal grid. To study the morphological parameters of the rat tracheal mucosa after removal from the experiment, the isolated lung tissue, carefully treated without crushing, was fixed in 9% formaldehyde, then added to paraffin and stained with a hematoxylin-eosin solution. Results. The studied indices of physical performance and static endurance indicate that the cold exposure statistically significantly increased the swimming time and the hanging time of rats on the grid after thirty days of consumption of functional confectionery. The morphological parameters of the tracheal mucosa of the 2nd experimental group did not differ significantly from those of the 1st experimental group. The content of ciliated and goblet cells in the 3rd experimental group was higher than in the 2nd and 1st groups of laboratory animals (p<0.05). The ratio of goblet cells to ciliated cells in rats of the 3rd group was 1:3.1, in the 2nd group - 1:3.5 vs 1:4.6 in the 1st group (p<0.05). This indicates an important role of secretion in the functioning of the epithelium when consuming functional confectionery products against the background of regular cold exposure. In this regard, it can be assumed that functional confectionery products can serve as a mean of protecting the mucociliary apparatus of rats during prolonged exposure to cold. Conclusion. The inclusion of sugary confectionery products, containing Schisandra chinensis berries juice and dry Eleutherococcus extract, in the diet of albino rats increased physical performance and endurance and the regeneration of the epithelial layer of the tracheal mucosa during cooling.

Contribution of Flavonoids and Iridoids to the Hypoglycaemic, Antioxidant, and Nitric Oxide (NO) Inhibitory Activities of Arbutus unedo L

This study aims at investigating the contribution of two classes of compounds, flavonoids and iridoids, to the bioactivity of Arbutus unedo L. leaves and fruits. The impact of different extraction procedures on phytochemicals content and hypoglycemic, antioxidant, and nitric oxide (NO) inhibitory activities of A. unedo fresh and dried plant materials was investigated. Ellagic acid 4-O-β-D-glucopyranoside, kaempferol 3-O-glucoside, and norbergenin were identified for the first time in this genus by using liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS). Three iridoids (gardenoside, geniposide, unedoside) are specifically identified in the leaves. Interestingly, asperuloside was extracted only from dried fruits by ethanol with Soxhlet apparatus. Extracts were screened for their potential antioxidant activities by using the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Activity Power (FRAP), and β-carotene bleaching tests. Based on the Global Antioxidant Score (GAS) calculation, the most promising antioxidant extract was obtained by hydroalcoholic maceration of dried leaves that showed half maximal inhibitory concentration (IC₅₀) of 0.42 and 0.98 μg/mL in ABTS and DPPH assays, respectively. The hypoglycaemic activity was investigated by α-amylase and α-glucosidase inhibition tests. Extracts obtained by ethanol ultrasound extraction of fresh leaves and hydroalcoholic maceration of fresh fruits (IC₅₀ of 19.56 and 28.42 μg/mL, respectively) are more active against α-glucosidase than the positive control acarbose (IC₅₀ of 35.50 μg/mL). Fruit extracts exhibited the highest anti-inflammatory activity.

The frontier between nutrition and pharma: The international regulatory framework of functional foods, food supplements and nutraceuticals

The link between diet and human health status has been repeatedly proved by strong scientific evidence, and developed societies demand food products with an added value beyond the satisfaction of hunger and the provision of nutrients. Functional foods, food supplements and nutraceuticals are at the interface between nutrition and pharma and opens the doors for seeking new therapeutic alternatives for the prevention of nutrition-related diseases. The present review is aimed at clarifying the differences between functional foods, food supplements and nutraceuticals as well as describing its regulatory framework in Europe, United States and Japan. Specific harmonized regulation for these products is needed. Functional foods, food supplements and nutraceuticals exert health-promoting properties and could be considered as potential candidates in the management of chronic diseases in combination with prescribed medication. Further research is essential for establishing which nutrition-pharma combinations are most favorable and suitable for each chronic disease.

Arbutus species (Ericaceae) as source of valuable bioactive products

In addition to nutrients, plant foods contain compounds that may provide additional health benefits improving the quality of life. Species from Arbutus genus (Ericaceae) represent a promising source of healthy phytochemicals. Bioactive compounds including such as anthocyanins, iridoids, phenols, triterpenes, sterols, and fatty acids are reported from Arbutus species. Some Arbutus species revealed promising biological activities including antioxidant, anti-inflammatory, anti-proliferative, anti-diabetic, and antimicrobial activities, and deserve for that reason further consideration for new drug discovery. However, only few species are investigated scientifically for their chemical profile and biological activities. The aim of this article is to summarize the current knowledge of the components and biological properties of Arbutus species common in Mediterranean area, as well as the future prospects on their applications as potentially valuable products.