INTRODUCTION
Paulownia is a genus of plants in the Paulowniaceae family, formerly classified as Scrophulariaceae. The plant was named in honour of the Queen of the Netherlands, Anna Pavlovna Romanov, who financed the trip to China from which this tree was first brought. The species of this genus include: Paulownia catalpifolia T. Gong ex D.Y. Hong,Paulownia elongata S.Y. Hu, Paulownia fargesii Franch.,Paulownia fortunei (Seem.) Hemsl., Paulownia kawakamiiT.Itô, Paulownia taiwaniana T.W. Hu & H.J. Chang,Paulownia tomentosa Steud. Paulownia Clon in Vitro 112, a hybrid of two species (Paulownia fortunei and Paulownia elongata ), known under the trade name Oxytree, has been popularized as a tree with exceptionally strong biomass growth, in the first two years of growth, with huge leaves producing ten times more oxygen than any other tree. Oxytree wood is half the weight of other hardwoods, and once dried, it does not gain moisture. Growing Oxytree is a perpetual motion, because a tree once planted is cut after 6 years, when it reaches 16 meters in height and 35 centimetres in diameter, and then grows back from the trunk and grows so quickly that after 4 years, it is ready to be cut again - such a process is repeated four more times. Paulownia Clon in Vitro112, unlike other Paulownia species, does not propagate by seeds or root cuttings, but only in vitro .
The species tested for the content of secondary metabolites is P. tomentosa var. tomentosa . The authors of these studies found in theleaves of P. tomentosa: matteucinol (syn. 4-O -methylfarrerol), ursolic acid (Zhu et al., 1986), homoeriodictyol (syn. hesperetin), 3-epiursolic acid, pomolic acid, corosolic acid, maslinic acid, β-sitosterol, daucosterol (Zhang and Li, 2011), apigenin (Zhao et al., 2012), luteolin, quercetin, (+)-catechin, (-)-epicatechin, naringenin, taxifolin, (Si et al., 2008a), 7,3’-dimethylquercetin (syn. rhamnazin), 7,3’,4’-trimethylquercetin, 7,3’,4’-trimethylmyricetin, 7,3’,4’,5’-tetramethylmyricetin (Wollenweber et al., 2008), diplacol, 3’-O -methyldiplacone, 3’-O -methyl-5’-hydroxydiplacone (syn. 6-geranyl-4’,5,5’,7-tetrahydroxy-3’-methoxyflavanone) (Kobayashi et al., 2008), acteoside (syn. verbascoside), isoacteoside (syn. isoverbascoside) (Schilling et al., 1982), 7-β-hydroxyharpagide, paulownioside, catalpol, aucubin, tomentoside, 7-hydroxytomentoside (Adriani et al., 1981), p-hydroxybenzoic acid, vanillic acid, gallic acid, cinnamic acid, p -coumaric acid, caffeic acid (Ota et al., 1993) ; and in the bark : quercetin, naringenin, 7-caffeoyl-acacetin (syn. 7-caffeoyl-4’-methoxyapigenin), isoacteoside (syn. isoverbascoside), isocampneoside II, cistanoside F (Si et al., 2011b), ilicifolioside A, campneoside II (syn. β-hydroxyacteoside), isoilicifolioside A (Si et al., 2008b), isocampneoside I (Si et al., 2008d), coniferin (syn. abietin, coniferosid, laricin), syringin (syn. eleutherosid B), acteoside (syn. verbascoside) (Sticher and Lahloub, 1982), β-Oxoacteoside (syn. tomentoside A), martynoside, campneoside I (Kang et al., 1994), catalpol (Plouvier, 1971), gallic acid, cinnamic acid (Ota et al., 1993); in the fruits : 7,3’,4’,5’-tetramethylmyricetin (Wollenweber et al., 2008), dihydrotricin, 6-isopentenyl-3’-O -methyltaxifolin, 3’-O -methyl-5’-hydroxydiplacone (syn. 6-geranyl-4’,5,5’,7-tetrahydroxy-3’-methoxyflavanone), 3’-O -methyl-5’-methoxydiplacol, schizolaenone C, 6-geranyl-3’,5,5’,7-tetrahydroxy-4’-methoxyflavanone, tomentodiplacone B, tomentodiplacone, tomentodiplacol, acteoside (syn. verbascoside), isoacteoside (syn. isoverbascoside) (Šmejkal et al., 2007a), 3,4’,5,5’,7-pentahydroxy-3’-methoxy-6-(3-methyl-2-butenyl)flavanone, diplacol, 3’-O -methyldiplacone, 3’-O -methyldiplacol (syn. diplacol 3’-O -methylether), 3’-O -methyl-5’-O -methyldiplacone (syn. 6-geranyl-4’,5,7-trihydroxy-3’,5’-dimethoxyflavanone, 6-geranyl-5,7-dihydroxy-3’,4’-dimethoxyflavanone, 3,3’,4’,5,7-pentahydroxy-6-[7-hydroxy-3,7-dimethyl-2(E)octenyl]flavanone, prokinawan, 4’,5,5’,7-tetrahydroxy-6-[6-hydroxy-3,7-dimethyl-2(E),7-octadienyl]-3’-methoxyflavanone, 3,3’,4’,5,7-pentahydroxy-6-[6-hydroxy-3,7-dimethyl-2(E),7-octadienyl]flavanone (Asai et al., 2008), 6-geranyl-3’,5,7-trihydroxy-4’-methoxyflavanone (syn. 4’-O -methyldiplacone), 6-geranyl-3,3’,5,7-tetrahydroxy-4’-methoxyflavanone (syn. 4’-O -methyldiplacol), 6-geranyl-3,3’,5,5’,7-pentahydroxy-4’-methoxyflavanone, tomentin A, B, C, D, E (Cho et al., 2012, 2013), tanariflavanone D, tomentomimulol, mimulone B (Schneiderova´et al., 2013), mimulone E, tomentodiplacone C, D, E, F, G, H, I, mimulone C, D (Navrátilova´ et al., 2013), 5,7-dihydroxy-6-geranylchromone (Šmejkal et al., 2008a) ; and in theflowers: apigenin, mimulone (syn. 6-geranylnaringenin, bonannione A), 5,4’-dihydroxy-7,3’-dimethoxyflavanone, diplacone (syn. propolin C, nymphaeol A) (Jiang et al., 2004), 5-hydroxy-7,3’,4’-trimethoxyflavanone, isoatriplicolide tiglate (Kim et al., 2010a, b), diplacol, 3’-O -methyldiplacone, 3’-O -methyldiplacol (syn. diplacol 3’-O -methylether), prokinawan (Kobayashi et al., 2008), p -ethoxybenzaldehyde (Yuan et al., 2009).
Paulownia tomentosa is a rich source of secondary metabolites of groups such as: non-prenylated flavonoid aglycones, C-prenylated and C-geranylated flavonoids, flavonoid glycosides, iridoids, phytosterols and phenolic acids. Biologically active compounds are used as traditional Chinese herbal remedies, as well as influence modern healthcare.
Flavonoids have a potential role as anti-cancer compounds for use in cervical and breast (Bulzomi et al., 2010, 2012), hepatoma, leukemia (Zhao et al., 2012), osteosarcoma (Chen et al., 2013), gastric cancer (Lu et al., 2013), colon adenocarcinoma (Sánchez-Tena et al. 2013) or prostate (Zhang and Coultas, 2013) cancer cell lines. Their antioxidant properties explain the cardioprotective effect (Paneerselvam et al., 2010; Psotova et al., 2004) and neuroprotective action (Losi et al., 2004). It has been found to exhibit antibacterial properties (Betts et al., 2013; Jiang et al., 2004; Mankovskaia et al., 2013) and antiviral (Khachatoorian et al,. 2012) biological activity against various pathogens.
Iridoid - catalpol shows radioprotective activity (Chen et al., 2013), neuroprotective (Li et al., 2004), cardioprotective effect on the heart muscle (Human); also increases glucose utilization by increased secretion of β-endorphin from the adrenal gland (Shieh et al. 2011). Aucubin had an antioxidant and protective effect on the pancreas and can alleviate the obesity-induced atherosclerosis (Park, 2013).
Phytosterols are potentially useful for the treatment of Alzheimer’s disease (Wilkinson et al., 2011). They show a cytotoxic effect against K562 and K562 / ADR human chronic myeloid leukemia, human HL60 and HL60 / ADR acute myeloid leukemia cancer cells and neoplastic cells human colon cancer cell lines SW480 and SW620 (Shan et al., 2011). They have anti-inflammatory (Deepak and Handa, 2000; Schinella et al., 2008), antimalarial (Moneriz et al., 2011), anti-diabetic effects (Sivakumar et al., 2009), reduce blood pressure, as well as are useful in the treatment of traumatic cerebral ischemia (Guan et al., 2011).
In the present study, a targeted identification and quantification of the secondary metabolites, present in Paulownia Clon in Vitro 112, were achieved by UPLC-MS/MS and UPLC-DAD.