The effect of different LED wavelengths on the components and biosynthesis of isoflavonoid in sprout Astragalus membranaceus.

An artificial light source is the optimal element for studying the usability of the medicinal plant Astragalus membranaceus as a sprout vegetable. Based on artificial light source conditions, formononetin (FO) level was the highest (2.6 mg/L) in A. membranaceus exposed to white light emitting diode (LED) light, and calycosin (CA) level was the highest (3.09 mg/L) in the plant exposed to red LED light. According to the publicly available transcriptome data of LED-exposed sprout A. membranaceus LED, reference genes related to the content enhancement of FO, an isoflavone compound, and those related to the content enhancement of CA were selected. The expression patterns of these genes were assayed using qPCR. Among the genes related to FO enhancement, Gene-225190T showed the highest mRNA levels in cells of LED-white light-exposed sprout A. membranaceus; among the genes related to CA enhancement, Gene_042770T showed the highest expression under red LED light. Most genes related to the overall biosynthesis regulation of flavonoids of the upper concept of isoflavone were highly expressed in response to red LED light, and the transcriptional level of 4CL in response to red LED light was the highest. Based on these results, the artificial light sources that regulated the FO and CA contents in sprouts A. membranaceus were white and red LED lights, and the selected reference genes were capable of regulating isoflavone biosynthesis.

Cellular Morphology and Transcriptome Comparative Analysis of Astragalus membranaceus Bunge Sprouts Cultured In Vitro under Different LED Light.

Astragalus membranaceus, the major components of which are saponins, flavonoids, and polysaccharides, has been established to have excellent pharmacological activity. After ginseng, it is the second most used medicinal plant. To examine the utility of A. membranaceus as a sprout crop for plant factory cultivation, we sought to establish a functional substance control model by comparing the transcriptomes of sprouts grown in sterile, in vitro culture using LED light sources. Having sown the seeds of A. membranaceus, these were exposed to white LED light (continuous spectrum), red LED light (632 nm, 1.58 µmol/m2/s), or blue LED light (465 nm, 1.44 µmol/m2/s) and grown for 6 weeks; after which, the samples were collected for transcriptome analysis. Scanning electron microscopy analysis of cell morphology in plants exposed to the three light sources revealed that leaf cell size was largest in those plants exposed to red light, where the thickest stem was observed in plants exposed to white light. The total number of genes in A. membranaceus spouts determined via de novo assembly was 45,667. Analysis of differentially expressed genes revealed that for the comparisons of blue LED vs. red LED, blue LED vs. white LED, and red LED vs. white LED, the numbers of upregulated genes were 132, 148, and 144, respectively. Binding, DNA integration, transport, phosphorylation, DNA biosynthetic process, membrane, and plant-type secondary cell wall biogenesis were the most enriched in the comparative analysis of blue LED vs. red LED, whereas Binding, RNA-templated DNA biosynthetic process, DNA metabolic process, and DNA integration were the most enriched in the comparative analysis of blue vs. white LED, and DNA integration and resolution of meiotic recombination intermediates were the most enrichment in the comparison between red LED vs. white LED. The GO term associated with flavonoid biosynthesis, implying the functionality of A. membranaceus, was the flavonoid biosynthetic process, which was enriched in the white LED vs. red LED comparison. The findings of this study thus indicate that different LED light sources can differentially influence the transcriptome expression pattern of A. membranaceus sprouts, which can provide a basis for establishing a flavonoid biosynthesis regulation model and thus, the cultivation of high-functional Astragalus sprouts.

Biochemical and Physiological Changes during Early Adventitious Root Formation in Chrysanthemum indicum Linné Cuttings.

Chrysanthemum indicum is an important ornamental and medicinal plant that is often difficult to propagate commercially because of its poor germination and low seed viability. This plant is mostly propagated by cutting, but the rooting is slow and non-uniform. The present investigation evaluated the regeneration capacity of stem cutting by examining the influence of auxins, growth medium, temperature, and explant type on adventitious root formation in C. indicum. The auxin-treated cuttings were planted in different growth substrates under greenhouse conditions. Among the different auxins tested, indole-3-butyric acid (IBA) more effectively induced roots. The cutting position of stock plants influenced rooting capacity. Cutting the stock plants from the apical region enhanced root number and length in the explants. Among the different explant types, apical stem cuts with 2000 ppm IBA produced a significantly higher number of adventitious roots when grown in vermiculite and perlite (V + P) at a ratio of 1:1 at 25 °C. High-performance liquid chromatography (HPLC) analysis revealed that protocatechuic acid, gentisic acid, chlorogenic acid, biochanin A, salicylic acid, caffeic acid, glycitein, and luteolin were the most dominant phenolic compounds present in C. indicum. These results indicate that IBA treatment promoted the synthesis and accumulation of phenolic compounds in C. indicum stem cuttings at the time of root formation. The present results demonstrate that applying auxins is essential for early root initiation and higher rooting success and thus may be beneficial for vegetative C. indicum propagation.

Neuroprotective Effect and Antioxidant Potency of Fermented Cultured Wild Ginseng Root Extracts of Panax ginseng C.A. Meyer in Mice.

Wild ginseng has better pharmacological effects than cultivated ginseng. However, its industrialization is limited by the inability to grow wild ginseng on a large scale. Herein, we demonstrate how to optimize ginseng production through cultivation, and how to enhance the concentrations of specific ginsenosides through fermentation. In the study, we also evaluated the ability of fermented cultured wild ginseng root extract (HLJG0701-ß) to inhibit acetylcholinesterase (AChE), as well as its neuroprotective effects and antioxidant activity. In invitro tests, HLJG0701-ß inhibited AChE activity and exerted neuroprotective and antioxidant effects (showing increased catalyst activity but decreased reactive oxygen species concentration). In invivo tests, after HLJG0701-ß was orally administered at doses of 0, 125, 250, and 500 mg/kg in an animal model of memory impairment, behavioral evaluation (Morris water maze test and Y-maze task test) was performed. The levels of AChE, acetylcholine (ACh), blood catalase (CAT), and malondialdehyde (MDA) in brain tissues were measured. The results showed that HLJG0701-ß produced the best results at a dose of 250 mg/kg or more. The neuroprotective mechanism of HLJG0701-ß was determined to involve the inhibition of AChE activity and a decrease in oxidative stress. In summary, both invitro and invivo tests confirmed that HJG0701-ß administration can lead to memory improvement.

Application of Light-Emitting Diodes for Improving the Nutritional Quality and Bioactive Compound Levels of Some Crops and Medicinal Plants.

Light is a key factor that affects phytochemical synthesis and accumulation in plants. Due to limitations of the environment or cultivated land, there is an urgent need to develop indoor cultivation systems to obtain higher yields with increased phytochemical concentrations using convenient light sources. Light-emitting diodes (LEDs) have several advantages, including consumption of lesser power, longer half-life, higher efficacy, and wider variation in the spectral wavelength than traditional light sources; therefore, these devices are preferred for in vitro culture and indoor plant growth. Moreover, LED irradiation of seedlings enhances plant biomass, nutrient and secondary metabolite levels, and antioxidant properties. Specifically, red and blue LED irradiation exerts strong effects on photosynthesis, stomatal functioning, phototropism, photomorphogenesis, and photosynthetic pigment levels. Additionally, ex vitro plantlet development and acclimatization can be enhanced by regulating the spectral properties of LEDs. Applying an appropriate LED spectral wavelength significantly increases antioxidant enzyme activity in plants, thereby enhancing the cell defense system and providing protection from oxidative damage. Since different plant species respond differently to lighting in the cultivation environment, it is necessary to evaluate specific wavebands before large-scale LED application for controlled in vitro plant growth. This review focuses on the most recent advances and applications of LEDs for in vitro culture organogenesis. The mechanisms underlying the production of different phytochemicals, including phenolics, flavonoids, carotenoids, anthocyanins, and antioxidant enzymes, have also been discussed.

Screening of Allelochemicals in Miscanthus sacchariflorus Extracts and Assessment of Their Effects on Germination and Seedling Growth of Common Weeds.

There is increasing interest in the application of bioherbicides because they are less destructive to the global ecosystem than synthetic herbicides. Research has focused on reducing the dependence upon synthetic herbicides by substituting them with environmentally and economically sustainable bioproducts. Allelopathic phytochemicals may be an efficient method for controlling weeds, benefitting both the environment and human health. This study addressed the allelopathic potential of Miscanthus sacchariflorus (MS) extracts on the germination, plant growth, biomass, and biochemical parameters (electrolyte leakage, photosynthetic pigments, and antioxidant enzyme activities) of weeds using laboratory and field experiments. Liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) showed the presence of 22 phenolic compounds, including Orientin, Luteolin, Veratric acid, Chlorogenic acid, Protocatechuic acid, p-Coumaric acid, and Ferulic acid. Leaf extracts of M. sacchariflorus either completely suppressed or partially reduced seed germination and affected the development of weed seedlings (root and shoot length), in a dose-dependent manner. Aqueous extracts of M. sacchariflorus reduced the fresh weight and dry weight, affected the photosynthetic pigment content (chlorophylls, carotenoids), influenced the electrolyte ion leakage, and stimulated the activity of antioxidant enzymes in a species-specific manner. Pearson's correlation analysis showed that the phenolic compound composition of M. sacchariflorus correlated with the variables tested, indicating that the phytochemicals present in the plant extracts of M. sacchariflorus are a potential source of bio-herbicides.

Assessment of Diversity in the Accessions of Setaria italica L. Based on Phytochemical and Morphological Traits and ISSR Markers.

This study was carried out to evaluate genetic diversity, phenolic compound composition, and biological activity of Setaria italica L. collected from different parts of South Korea. Antioxidant potential of seeds was estimated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, and antimicrobial activity was determined by evaluating the minimum inhibitory concentration (MIC). Eight phenolic acids and 3 flavonoids were identified and quantified, among which myricetin and salicylic acid were the most dominant phytochemical compounds detected in the majority of accessions. The antioxidant potential of the leaf extracts of all the accessions was significantly higher (ranging from 32.33 ± 1.53 µg mL-¹ in SI-03 to 87.87 ± 1.63 µg mL-¹) in SI-10 than that of the root, stem, or seeds. Among the 15 accessions, methanolic extracts of the SI-15 accession strongly suppressed the growth of Escherichia coli (250 µg mL-¹). Accessions SI-14 and SI-15 showed positive antimicrobial activity against all gram-positive bacteria. Interestingly, extracts of all accessions were more sensitive towards E. coli and Staphylococcus aureus, with MICs ranging from 250 to 1000 µg mL-¹. Three phenolic acids, namely chlorogenic acid, catechin, caffeic acid, naringin, hesperetin, and myricetin, were found to be moderately positively correlated with antioxidant activities. A wide range of diversity was observed in morphological traits, namely plant height (99.33 to 201.33 cm), culm length (67.10 to 160.00 cm), spike length (12.80 to 24.00 cm), 1000 seeds weight 1.44 to 2.91 g), bloom beginning (93.67 to 128.00 days), and full bloom (99.67 to 135 days). A dendogram generated from unweighted pair group method with arithmetic mean clustering (UPGMA) cluster analysis based on the morphological traits and inter simple sequence repeat (ISSR) marker data revealed three major groups. However, no clear correlation between these two different approaches was found. The average Shannon's information index value (I) was 0.492, and it ranged from 0 to 0.693. The average expected heterozygosity (He) was 0.335, and it ranged from 0 to 0.499. The substantial variation in the morphological traits, bioactive properties, and genetic diversity among the accessions may provide useful information for breeding programs attempting to obtain S. italica with improved bioactive properties.

Expressed Sequence Tags Analysis and Design of Simple Sequence Repeats Markers from a Full-Length cDNA Library in Perilla frutescens (L.).

Perilla frutescens is valuable as a medicinal plant as well as a natural medicine and functional food. However, comparative genomics analyses of P. frutescens are limited due to a lack of gene annotations and characterization. A full-length cDNA library from P. frutescens leaves was constructed to identify functional gene clusters and probable EST-SSR markers via analysis of 1,056 expressed sequence tags. Unigene assembly was performed using basic local alignment search tool (BLAST) homology searches and annotated Gene Ontology (GO). A total of 18 simple sequence repeats (SSRs) were designed as primer pairs. This study is the first to report comparative genomics and EST-SSR markers from P. frutescens will help gene discovery and provide an important source for functional genomics and molecular genetic research in this interesting medicinal plant.

Improved antioxidant activity in transgenic Perilla frutescens plants via overexpression of the γ-tocopherol methyltransferase (γ-tmt) gene.

The main goal of this study was to generate transgenic Perilla frutescens with enhanced antioxidant properties by overexpressing the γ-tocopherol methyltransferase (γ-tmt) gene. In this study, the antioxidant activity of methanolic crude extracts of transgenic and non-transgenic control plants was investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. Free radical scavenging activity was evaluated using α-tocopherol and butylated hydroxyl toluene as standard antioxidants. In general, the ethyl acetate fraction of transgenic P. frutescens showed stronger DPPH radical scavenging activity than the ethyl acetate fraction from non-transgenic control plants (IC50 2.00 ± 0.10 and 5.53 ± 0.40 µg ∙ ml(-1), respectively). High-performance liquid chromatography analysis of phenolic acids in leaf extracts confirmed increased levels of 16 individual phenolic compounds in two transgenic lines (pf47-5 and pf47-8) compared with control plants. Changes in the phenolic compound profile and α-tocopherol content were correlated with the antioxidant properties of transgenic plants, indicating that the introduction of transgene γ-tmt influenced the metabolism of phenolic compounds and subsequently produced biochemical changes in the transformants. There were no significant differences in photosynthetic rate in the transgenic plants as compared to the non-transgenic control plants, suggesting that the alteration of phenolic compounds and tocopherol composition had little impact on photosynthesis.

Antioxidant, antimicrobial activity and inhibition of α-glucosidase activity by Betula alnoides Buch. bark extract and their relationship with polyphenolic compounds concentration.

Betula alnoides has been widely used in local traditional medicinal treatment for a variety of diseases, wounds and to cure diabetes. The air-dried, powdered (200 g) bark was extracted with 80% methanol at room temperature. The combined 80% methanolic extract was partitioned with organic solvents to yield n-hexane, ethyl acetate (EtOAc), n-butanol (BuOH; water saturated), and aqueous fractions for the investigation of antioxidant and antimicrobiology and α-glucosidase activity effects (GAE) of B. alnoides. Antioxidant activity was studied by using antioxidant tests, including electron donation ability test, reducing power, and metal-chelating activity assay. Antioxidant, antimicrobial activity and α-glucosidase inhibitory effect of 80% methanolic extracts and fractions derived from the bark of B. alnoides were evaluated and determined. The results showed that 80% methanolic extracts exhibited high 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity (80.68%). In addition, both the 80% methanolic extract and EtOAc fraction exhibited more potent reducing activity than did butylated hydroxyanisole (BHA) and trolox. The aqueous fraction had higher metal-chelating activity than other fractions. The EtOAc fraction had the highest phenolic and flavonoid content (217.73 ± 1.02 mg GAE/g extract, and 38.42 ± 1.87 mg QE/g extract, respectively). The 80% methanolic extract and EtOAc fraction showed higher levels of antimicrobial activity than did other fractions. The 80% methanolic extract had the most powerful α-glucosidase inhibitory effect (98.46%) at a concentration of 40 µg/mL. The results suggest that bark extracts of B. alnoides could be a potential source of natural antioxidants and for treating pathogenic diseases.

Hovenia dulcis--an Asian traditional herb.

Hovenia dulcis Thunb., known as Japanese raisin tree, is commonly found in East Asia. It has a long history as a food supplement and traditional medicine in Japan, China and Korea, but is little known and used in Western countries so far. This minireview summarizes traditional uses and current knowledge on the pharmacology and phytochemistry of H. duclcis and covers, in particular, literature from specialized Asian journals that are not readily accessible. Extracts from H. dulcis accelerate detoxification of ethanol, and possess hepatoprotective, antioxidative, antimicrobial and antidiabetic properties. Although the underlying molecular mechanisms are not fully understood, free radical scavenging and enhancement of ethanol catabolism have been reported.

Chemical constituents of rice (Oryza sativa) hulls and their herbicidal activity against duckweed (Lemna paucicostata Hegelm 381).

Four new compounds, stigmastanol-3beta-p-glyceroxydihydrocoumaroate (1), stigmastanol-3beta-p-butanoxydihydrocoumaroate (2), lanast-7,9(11)-dien-3alpha,15alpha-diol-3alpha-D-glucofuranoside (3) and 1-phenyl-2-hydroxy-3,7-dimethyl-11-aldehydic-tetradecane-2-beta-D-glucopyranoside (4), along with several known compounds were isolated from the methanol extract of hulls of Oryza sativa. The new structures were established by one- and two-dimensional NMR and in combination with IR, EI/MS, FAB/MS and HR-FAB/ MS. Compound (3) strongly inhibited the growth of duckweed (Lemna paucicostata Hegelm 381), whilst compounds (2) and (4) exhibited weak inhibition.