Ebulin from Dwarf Elder (Sambucus ebulus L.): A Mini-Review

Abstract

Sambucus ebulus L. (dwarf elder) is a medicinal plant, the usefulness of which also as food is restricted due to its toxicity. In the last few years, both the chemistry and pharmacology of Sambucus ebulus L. have been investigated. Among the structural and functional proteins present in the plant, sugar-binding proteins (lectins) with or without anti-ribosomal activity and single chain ribosome-inactivating proteins (RIPs) have been isolated. RIPs are enzymes (E.C. 3.2.2.22) that display N-glycosidase activity on the 28S rRNA subunit, leading to the inhibition of protein synthesis by arresting the step of polypeptide chain elongation. The biological role of all these proteins is as yet unknown. The evidence suggests that they could be involved in the defense of the plant against predators and viruses or/and a nitrogen store, with an impact on the nutritional characteristics and food safety. In this mini-review we describe all the isoforms of ebulin that have to date been isolated from dwarf elder, as well as their functional characteristics and potential uses, whilst highlighting concern regarding ebulin toxicity.

Plant Ribosome-Inactivating Proteins: Progesses, Challenges and Biotechnological Applications (and a Few Digressions)

“…Plant RIPs can be divided into three main classes: type I like saporin from Saponaria officinalis are composed of a single polypeptide chain of approximately 30 KDa, type II as ricin from Ricinus communis [ 8 ] are heterodimers consisting of an A chain, functionally equivalent to the type I polypeptide linked via a disulphide bridge to a B subunit endowed with lectin-binding properties [ 9 ]. For a long time, all type 2 RIPs were considered to be highly potent toxins, but, so far, there are also known type II RIPs, which are not or only less toxic in vivo, and therefore they are denominated as non-toxic type II RIPs [ 10 , 11 ]. Finally, type III RIPs are polypeptides, which are synthesized as inactive precursors (ProRIPs) that will require proteolytic processing events to form an active RIP [ 12 ].…”

Lectin Digestibility and Stability of Elderberry Antioxidants to Heat Treatment In Vitro

“…Common elderberry ( Sambucus nigra L.) contains type II RIPs in bark (nigrin b-SNA V, SNA I and related proteins), fruits (nigrin f) and seeds (nigrin s) [ 5 ]. Dwarf elder ( Sambucus ebulus L.) also contains type II RIPs referred to as ebulins in fruits (ebulin f), leaves (ebulin l), and rhizomes (ebulins r1 and r2) [ 22 ]. In addition to RIPs, Sambucus spp.…”

A new age for biomedical applications of Ribosome Inactivating Proteins (RIPs): from bioconjugate to nanoconstructs

“…The absence of the lectin chain significantly limits the access of type 1 RIPs into cells, determining a consequent lower cytotoxicity. Beyond these, some non-canonical RIPs, such as tetrameric ebulin [ 6 , 7 ] or proteolytic activated maize b-32 [ 8 ] were also found.…”