Carotenoid profile produced by Bacillus licheniformis Rt4M10 isolated from grapevines grown in high altitude and their antioxidant activity

Optimization and multiple in vitro activity potentials of carotenoids from marine Kocuria sp. RAM1

Marine pigmented bacteria are a promising natural source of carotenoids. Kocuria sp. RAM1 was isolated from the Red Sea Bohadschia graeffei collected from Marsa Alam, Egypt, and used for carotenoids production. The extracted carotenoids were purified by thin-layer chromatography (TLC). The characteristic UV absorbance of the three purified fractions gave us an inkling of what the purified pigments were. The chemical structures were confirmed by nuclear magnetic resonance spectroscopy (NMR) and LC-ESI-QTOF-MS/MS. The three different red pigments were identified as two C₅₀-carotenoids, namely bisanhydrobacterioruberin and trisanhydrobacterioruberin, in addition to 3,4,3',4'-Tetrahydrospirilloxanthin (C₄₂-carotenoids). Kocuria sp. RAM1 carotenoids were investigated for multiple activities, including antimicrobial, anti-inflammatory, antioxidant, anti-HSV-1, anticancer, antidiabetic and wound healing. These new observations suggest that Kocuria sp. RAM1 carotenoids can be used as a distinctive natural pigment with potent properties.

The Biodiversity of Grapevine Bacterial Endophytes of Vitis amurensis Rupr

In this paper, the composition profiles of bacterial endophytes in wild-growing Amur grape Vitis amurensis Rupr. grown in the south of the Russian Far East were analyzed using both a cultivation-dependent (sowing bacteria) and a cultivation-independent (next generation sequencing, NGS) approach. Both methods revealed the prevalent endophytes in V. amurensis were represented by Gammaproteobacteria—40.3–75.8%, Alphaproteobacteria—8.6–18.7%, Actinobacteria—9.2–15.4%, and Bacilli—6.1–6.6%. NGS also showed a large proportion of Bacteroidia (12.2%) and a small proportion of other classes (less than 5.7%). In general, NGS revealed a greater variety of classes and genera in the endophytic bacterial community due to a high number of reads (574,207) in comparison with the number of colonies (933) obtained after the cultivation-dependent method. A comparative analysis performed in this study showed that both wild grape V. amurensis from Russia and domesticated cultivars of V. vinifera from Germany and California (USA) exhibit the same basic composition of endophytic bacteria, while the percentages of major taxa and minor taxa showed some differences depending on the plant organ, grape individuals, environmental conditions, and sampling time. Furthermore, the obtained data revealed that lower temperatures and increased precipitation favored the number and diversity of endophytic bacteria in the wild Amur grape. Thus, this study firstly described and analyzed the biodiversity of endophytic bacteria in wild grapevine V. amurensis.

Grapevine rootstock and soil microbiome interactions: Keys for a resilient viticulture

Soil microbiota has increasingly been shown to play an integral role in viticulture resilience. The emergence of new metagenomic and culturomic technologies has led to significant advances in the study of microbial biodiversity. In the agricultural sector, soil and plant microbiomes have been found to significantly improve resistance to environmental stressors and diseases, as well as influencing crop yields and fruit quality thus improving sustainability under shifting environments. Grapevines are usually cultivated as a scion grafted on rootstocks, which are selected according to pedoclimatic conditions and cultural practices, known as terroir. The rootstock connects the surrounding soil to the vine's aerial part and impacts scion growth and berry quality. Understanding rootstock and soil microbiome dynamics is a relevant and important field of study, which may be critical to improve viticulture sustainability and resilience. This review aims to highlight the relationship between grapevine roots and telluric microbiota diversity and activity. In addition, this review explores the concept of core microbiome regarding potential applications of soil microbiome engineering with the goal of enhancing grapevine adaptation to biotic and abiotic stress.

Biodiversity of endophytic bacteria and fungi of wild grapes Vitis amurensis Rupr

The diversity of endophytic bacteria and fungi of V. amurensis grape plants growing in the suburbs of Vladivostok in the summer and autumn periods of 2018-2020 was analyzed. About 600 strains of bacteria and 160 strains of fungi were inoculated from peripherally sterilized leaves and stems of V. amurensis. Isolated bacteria were representatives of 36 genera: Actinobacterium, Acinetobacter, Agrobacterium, Arthrobacter, Bacillus, Buttiauxella, Curtobacterium, Duganella, Erwinia, Enterobacter, Frigoribacterium, Frondihabitans, Klebsiella, Leclercia, Lelliottia, Methylobacterium, Microbacterium, Mucilaginibacter, Luteibacter, Lysinimonas, Pantoea, Paenibacillus, Parageobacillus, Pedobacter, Phyllobacterium, Plantibacter, Pseudomonas, Pullulanibacillus, Raoultella, Rhizobium, Sphingomonas, Staphylococcus, Stenotrophomonas, Streptomyces, Serratia, Xanthomonas. The largest number of strains were representatives of the genera Erwinia, Pantoae and Pseudomonas. Endophytic grape fungi were represented by 25 genera: Alternaria, Annulohypoxylon, Aureobasidium, Biscogniauxia, Cladosporium, Colletotrichum, Coniochaeta, Coprinellus, Davidiellaceae, Didymella, Discosia, Epicoccum, Fusarium, Hypoxylon, Neosetophoma, Nemania, Neurospora, Nigrospora, Paraphoma, Penicillium, Pestalotiopsis, Pestalosphaeria, Phoma, Trichoderma, Xylaria. The largest number of representatives were of the genus Didymella, Cladosporium and Colletotrichum.

The Role of the Endophytic Microbiome in the Grapevine Response to Environmental Triggers

Endophytism within Vitis represents a topic of critical relevance due to the multiple standpoints from which it can be approached and considered. From the biological and botanical perspectives, the interaction between microorganisms and perennial woody plants falls within the category of stable relationships from which the plants can benefit in multiple ways. The life cycle of the host ensures persistence in all seasons, repeated chances of contact, and consequent microbiota accumulation over time, leading to potentially high diversity compared with that of herbaceous short-lived plants. Furthermore, grapevines are agriculturally exploited, highly selected germplasms where a profound man-driven footprint has indirectly and unconsciously shaped the inner microbiota through centuries of cultivation and breeding. Moreover, since endophyte metabolism can contribute to that of the plant host and its fruits' biochemical composition, the nature of grapevine endophytic taxa identities, ecological attitudes, potential toxicity, and clinical relevance are aspects worthy of a thorough investigation. Can endophytic taxa efficiently defend grapevines by acting against pests or confer enough fitness to the plants to endure attacks? What are the underlying mechanisms that translate into this or other advantages in the hosting plant? Can endophytes partially redirect plant metabolism, and to what extent do they act by releasing active products? Is the inner microbial colonization necessary priming for a cascade of actions? Are there defined environmental conditions that can trigger the unleashing of key microbial phenotypes? What is the environmental role in providing the ground biodiversity by which the plant can recruit microsymbionts? How much and by what practices and strategies can these symbioses be managed, applied, and directed to achieve the goal of a better sustainable viticulture? By thoroughly reviewing the available literature in the field and critically examining the data and perspectives, the above issues are discussed.