Hemp (Cannabis sativa L.) Seed Protein-EGCG Conjugates: Covalent Bonding and Functional Research.

In order to make HPI have a wide application prospect in the food industry, we used EGCG to modify HPI. In this study, we prepared different concentrations (1, 2, 3, 4, and 5 mM) of (-)-epigallocatechin gallate (EGCG) covalently linked to HPI and use methods such as particle size analysis, circular dichroism (CD), and three-dimensional fluorescence spectroscopy to study the changes in the structure and functional properties of HPI after being covalently combined with EGCG. The particle size data indicated that the covalent HPI-EGCG complex was larger than native HPI, and the particle size was mainly distributed at about 200 µm. CD and three-dimensional fluorescence spectroscopy analyses showed that the conformation of the protein was changed by conjugation with EGCG. The ß-sheet content decreased from 82.79% to 66.67% after EGCG bound to the protein, and the hydrophobic groups inside the protein were exposed, which increased the hydrophobicity of the protein and changed its conformation. After HPI and 1 mM of EGCG were covalently bonded, the solubility and emulsifying properties of the covalent complex were improved compared with native HPI. These results indicated that HPI-EGCG conjugates can be added in some foods.

The masseter inhibitory reflex and the recovery of the reflex after magnetic stimulation in normal subjects / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To analyze the masseter inhibitory reflex (MIR) and the recovery cycle of the MIR reflex after magnetic stimulation in normal subjects.</p><p><b>METHODS</b>In 30 healthy subjects we studied the MIR evoked by single magnetic stimulation in the mental territory. Masseter electromyographic activity, latency and duration of the early silent periods (SP1) and late silent periods (SP2), and SP2 amplitude percent were recorded. Paired stimuli technique was used, conditioning and test stimuli were delivered at different interstimulus intervals (ISI), ie.100, 200, 300, 400, 500, and 600 ms, then the recovery cycle of the MIR was analyzed.</p><p><b>RESULTS</b>Latency of SP1 was 12.1 (11.1, 14.4) ms, and duration of the SP1 was (17.3 ± 2.9) ms. Latency of SP2 was (47.7 ± 6.0) ms, and duration of the SP2 was (39.7 ± 13.3) ms. SP2 amplitude percent was 100.0%. With the paired stimuli technique, SP1 of the inhibitory reflex evoked by the test stimuli was found to be stable at every ISIs, but SP2 of the inhibitory reflex evoked by the test stimuli, instead, varied according to different ISI. With the short ISI, the area of SP2 evoked by the test stimuli was reduced, and with the increase of the ISI, the recovery degree of the area of SP2 evoked by the test stimuli was ascending, at 100 ms the SP2 amplitude percent was 17.1%, at 400 ms it was 93.4%, and it was close to 100% at 600 ms.</p><p><b>CONCLUSIONS</b>The study indicates that the use of the MIR elicited by the single and paired magnetic stimulation may be useful to examine or quantify some craniofacial diseases.</p>

[Construction of expression vector driven by tobacco root-specific promoter and transformation into Rhodiola hairy root].

OBJECTIVE: To construct root-specific promoter of plant expression vector and transformate into Rhodiola hairy root. METHODS: The expression vector pCA-Tob7: UGTR, driven by tobacco root-specific promoter TobRB7, was constructed from pCAM-BIA1301 by substituting the CaMV 35S promoter and GUS gene with TobRB7 and UGTR(a glycosyltransferase gene), respectively. The pCA-Tob7: UGTR vector was introduced into Agrobacterium tumefaciens strain, and the hairy root of Rhodiola were then transformed. RESULTS: Some Kanamycin resistant plants were positive,which indicated that the expression vector had integrated into Rhodiola hairy root genome. CONCLUSION: Root-specific promoter of plant expression vector is constructed and the hairy root of Rhodiola are transformed for future research.

A tyrosine decarboxylase catalyzes the initial reaction of the salidroside biosynthesis pathway in Rhodiola sachalinensis.

Salidroside, the 8-O-ß-D-glucoside of tyrosol, is the main bioactive component of Rhodiola species and is found mainly in the plant roots. It is well known that glucosylation of tyrosol is the final step in the biosynthesis of salidroside; however, the biosynthetic pathway of tyrosol and its regulation are less well understood. A summary of the results of related studies revealed that the precursor of tyrosol might be tyramine, which is synthesized from tyrosine. In this study, a cDNA clone encoding tyrosine decarboxylase (TyrDC) was isolated from Rhodiola sachalinensis A. Bor using rapid amplification of cDNA ends. The resulting cDNA was designated RsTyrDC. RNA gel-blot analysis revealed that the predominant sites of expression in plants are the roots and high levels of transcripts are also found in callus tissue culture. Functional analysis revealed that tyrosine was best substrate of recombinant RsTyrDC. The over-expression of the sense-RsTyrDC resulted in a marked increase of tyrosol and salidroside content, but the levels of tyrosol and salidroside were 274 and 412%, respectively, lower in the antisense-RsTyrDC transformed lines than those in the controls. The data presented here provide in vitro and in vivo evidence that the RsTyrDC can regulate the tyrosol and salidroside biosynthesis, and the RsTyrDC is most likely to have an important function in the initial reaction of the salidroside biosynthesis pathway in R. sachalinensis.

Characterization of glycosyltransferases responsible for salidroside biosynthesis in Rhodiola sachalinensis.

Salidroside, the 8-O-ß-D-glucoside of tyrosol, is a novel adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor. Due to the scarcity of R. sachalinensis and its low yield of salidroside, there is great interest in enhancing production of salidroside by biotechnological manipulations. In this study, two putative UDP-glycosyltransferase (UGT) cDNAs, UGT72B14 and UGT74R1, were isolated from roots and cultured cells of methyl jasmonate (MeJA)-treated R. sachalinensis, respectively. The level of sequence identity between their deduced amino acid sequences was ca. 20%. RNA gel-blot analysis established that UGT72B14 transcripts were more abundant in roots, and UGT74R1 was highly expressed in the calli, but not in roots. Functional analysis indicated that recombinant UGT72B14 had the highest level of activity for salidroside production, and that the catalytic efficiency (Vmax/Km) of UGT72B14 was 620% higher than that of UGT74R1. The salidroside contents of the UGT72B14 and UGT74R1 transgenic hairy root lines of R. sachalinensis were also ∼420% and ∼50% higher than the controls, respectively. UGT72B14 transcripts were mainly detected in roots, and UGT72B14 had the highest level of activity for salidroside production in vitro and in vivo.

[Comparison of composition of aetherolea and alcohol extraction from ChangBai Mountain purple common perilla].

OBJECTIVE: To compare the chemical constituents of Aetherolea and Alcohol Extraction of purple common perilla of ChangBai Mountain. METHODS: We used water vapor distillation and alcohol extraction method, then analyzed identification by thin-layer chromatography and GC-MS. RESULTS: The main chemical compositions of aetherolea were caryophyllen, caryophyllene oxid, ylangene, 4-(2-Methylcyclohex-1-enyl)-but-2-enal and 3,7-dimethyl-1,6-Octadien-3-ol and the main chemical compositions of alcohol extraction were 10-hendeca-acetylene-1-alcohol, n-hexsdecanoic acid (E)-7,11-dimethyl-3-methylene- 1,6,10-Dodecatriene and so on. CONCLUSION: Other specific compositions including tau. -Muurolol,3H-3a,7-Methanoazulene,2 ,4,5,6,7,8-hexahydro-1,4,9,9-Tetram-ethyl-, [3aR-(3a. alpha, 4. beta 7. alpha)], Astaxanthin and Curan-17-oicacid, 19-acetyl-2,16-didehydro-20-hydroxy-, methyl ester, (19S) have special functions of sterilizing, cancer preventing and immunity improving, which are significantly different from the compositions extracted from other species.

Molecular cloning and overexpression of a novel UDP-glucosyltransferase elevating salidroside levels in Rhodiola sachalinensis.

Salidroside is a novel effective adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor. Because this plant is a rare resource and has low yield, there is great interest in enhancing the production of salidroside. In this study, a putative UDP-glucosyltransferase (UGT) cDNA, UGT73B6, was isolated from Rhodiola sachalinensis using a rapid amplification of cDNA ends (RACE) method. The cDNA was 1,598 bp in length encoding 480 deduced amino acid residues with a conserved UDP-glucose-binding domain (PSPG box). Southern blot analysis of genomic DNA indicated that UGT73B6 existed as a single copy gene in the R. sachalinensis genome. Northern blot analysis revealed that transcripts of UGT73B6 were present in roots, calli and stems, but not in leaves. The UGT73B6 under 35S promoter with double-enhancer sequences from CaMV-Omega and TMV-Omega fragments was transferred into R. sachalinensis via Agrobacterium tumefaciens. PCR, PCR-Southern and Southern blot analyses confirmed that the UGT73B6 gene had been integrated into the genome of transgenic calli and plants. Northern blot analysis revealed that the UGT73B6 gene had been expressed at the transcriptional level. High performance liquid chromatography (HPLC) analysis indicated that the overexpression of the UGT73B6 gene resulted in an evident increase of salidroside content. These data suggest that the cloned UGT73B6 can regulate the conversion of tyrosol aglycon to salidroside in R. sachalinensis. This is the first cloned glucosyltransferase gene involved in salidroside biosynthesis.