Production of Prenylated Stilbenoids in Hairy Root Cultures of Peanut (Arachis hypogaea) and Its Wild Relatives A. ipaensis and A. duranensis via an Optimized Elicitation Procedure

Abstract

Prenylated stilbenoids are phenolic compounds produced in a small number of plants such as peanut (Arachis hypogaea) to counteract biotic and abiotic stresses. In addition to their role in plant defense, they exhibit biological activities with potential application in human health. Whereas non-prenylated stilbenoids such as resveratrol are commercially available, the availability of prenylated stilbenoids is limited. To this end, hairy root cultures of peanut were developed as an elicitor-controlled bioproduction platform for prenylated stilbenoids. An orthogonal array design approach led to the elucidation of an optimized elicitation procedure consisting of co-treatment of the hairy root cultures with 18 g/L methyl-β-cyclodextrin, 125 µM methyl jasmonate, 3 mM hydrogen peroxide (H 2 O 2 ) and medium supplementation with additional 1 mM magnesium chloride. After 168-h of elicitor treatment, the combined yield of the prenylated stilbenoids arachidin-1, arachidin-2, arachidin-3 and arachidin-5 reached approximately 750 mg/L (equivalent to 107 mg/g DW). Moreover, hairy root cultures from the wild Arachis species A. duranensis and A. ipaensis were developed and shown to produce prenylated stilbenoids upon elicitor treatment. These wild Arachis hairy root lines may provide a platform to elucidate the biosynthetic origin of prenylated stilbenoids in peanut.Molecules 2020, 25, 509 of 13Recent research also demonstrated the anti-inflammatory activity of arachidin-1 in endothelial cells [5]. The anticancer activity of arachidin-1 isolated from germinated peanut kernels was demonstrated in HL-60 cells through caspase-dependent and caspase-independent pathways [6]. Arachidin-1 and arachidin-3 purified from peanut hairy root cultures exhibited antiviral activity in rotavirus infected HT29.f8 cells by inhibiting rotavirus replication [7]. This antiviral activity was not observed with either of their non-prenylated analogs, piceatannol or resveratrol, suggesting that the antiviral mechanism might depend on the prenylated moiety (3-methyl-1-butenyl moiety) of arachidin-1 and arachidin-3. A cannabinoid receptor binding study of different peanut stilbenoids also demonstrated that the prenylated moiety of arachidin-1 and arachidin-3 improved binding affinity to type II cannabinoid receptor [8]. Despite the diverse bioactivities of arachidin-1 and arachidin-3 demonstrated in in vitro studies, the limited availability of these prenylated stilbenoids has hindered their further progress for in vivo studies. Moreover, the bioactivities of arachidin-5 and arachidin-2, two other prenylated stilbenoids identified from peanut with 3,3-dimethylallyl moiety instead of that on arachidin-1 and arachidin-3 ( Figure 1) have not been explored due to their overall low yield.

The Role of Polyphenols in Abiotic Stress Response: The Influence of Molecular Structure

“…The defense responses of peanut ( Arachis hypogaea ) to biotic and abiotic stresses included the synthesis of prenylated stilbenoids such as arachidin-1, arachidin-2, arachidin-3, and isopentadienyl trihydroxystilbene [ 173 ]. For example, co-treatment of the hairy root culture of Arachis hypogaea with ethyl-β-cyclodextrin, methyl jasmonate, hydrogen peroxide (H 2 O 2 ), and magnesium chloride induced prenylated stilbenoids arachidin-1, arachidin-2, arachidin-3, and arachidin-5 [ 174 ]. In general, prenylation of aromatic compounds plays an important role in the diversification of plant secondary metabolites and contributes to the enhancement of the biological activity of polyphenolic compounds [ 175 ].…”

Phytostilbenes as agrochemicals: biosynthesis, bioactivity, metabolic engineering and biotechnology

“…469 In optimized conditions a production of 750 mg/L of total prenylated stilbenoids after 168h was reported, as well. 470 Engineering tobacco HRs with genes involved in stilbene biosynthesis or regulation has been carried out in a pioneering study with a limited success. 471 However, this first work opened an interesting and promising way to produce stilbenoids in fast growing HRs.…”

Antioxidant Assessment of Prenylated Stilbenoid-Rich Extracts from Elicited Hairy Root Cultures of Three Cultivars of Peanut (Arachis hypogaea)

“…The hairy root cultures were grown till the mid-log stage prior to elicitation [17,30]. The spent medium was discarded and replaced with 100 mL of MSV medium containing 3% sucrose with 125 µM methyl jasmonate (MeJA), 18 g/L cyclodextrin (CD), 3 mM hydrogen peroxide (H 2 O 2 ), and 1 mM magnesium chloride (MgCl 2 ) as described before [18]. All elicitation was carried out under continuous darkness at 28 • C for 168 h.…”

“…Hull was established previously using Agrobacterium rhizogenes to enhance the production of non-prenylated and prenylated stilbenoids [17]. The hairy roots when treated with a combination of methyl jasmonate (MeJA), cyclodextrin (CD), hydrogen peroxide, and magnesium chloride secrete several stilbenoids and their derivatives into the culture medium and thus these compounds can be extracted from the culture medium [18]. This stilbenoid-rich extract from peanut hairy root culture medium is rich in the non-prenylated stilbenoid resveratrol and prenylated stilbenoids arachidin-5, arachidin-1, arachidin-2, arachidin-3, and others with diverse biological activity (Figure 1).…”