Effect of Picloram and Desiccation on the Somatic Embryogenesis of Lycium barbarum L

An efficient and reproducible in vitro method for indirect somatic embryogenesis was optimized by culturing leaf and leaf with petiole explants of Lycium barbarum L. Murashige and Skoog (MS) medium, supplemented with various concentrations of Picloram and 2,4-Dichlorophenoxyacetic acid (2,4-D), individually and in combinations, were tested. Picloram (1.0 µM) showed a better response compared to 2,4-D and results indicate it to be a better auxin for induction of somatic embryos for Goji berry. It was seen that the leaf explants were more responsive in callus and somatic embryo induction than the leaf with petiole explant when incubated in the dark for 5 weeks. Embryogenic callus, after being transferred to MS medium containing Benzyl amino purine (BAP) in 1.0 µM, 5.0 µM and 10.0 µM, began to differentiate in light after one week. MS medium with 1.0 µM Picloram + 10 µM BAP resulted as the most favorable treatment for somatic embryogenesis in Lycium barbarum L. Removal of plant growth regulators from MS medium and culturing induced calluses under 16 h photoperiod resulted in globular, heart, torpedo, cotyledons, and further development into plantlets. Well-developed plants have been obtained and are capable of acclimatizing in ex vitro conditions. In addition, the effects of desiccation treatments (0, 1, 3, 6, 9 h, and 12 h) on embryogenic callus for somatic embryo induction were found to be directly proportional to the length of desiccation treatment at room temperature. After 9 h and 12 h of desiccation treatments, 60% and 90% of plated calluses resulted in somatic embryos, respectively. In a L. barbarum callus mass, Acetocarmine and Evans blue double staining differentiated between embryogenic and non-embryogenic callus. These findings will help Goji berry improvement by elite clone production, ex situ conservation projects, scaling up plant production, and agronomy for the commercial production of this superfruit in the future.

Biotechnological interventions and production of galanthamine in Crinum spp

Genus Crinum L. is a member of the Amaryllidaceae family having beautiful, huge, ornamental plants with umbels of lily-like blooms that are found in tropical and subtropical climates all over the world. For thousands of years, Crinum has been used as a traditional medicine to treat illnesses and disorders. Numerous distinct alkaloids of the Amaryllidaceae group, whose most well-known properties include analgesic, anticholinergic, antitumor, and antiviral, have recently been discovered by phytochemical analyses. However, because of decades of overexploitation for their economically significant bioactive ingredients and poor seed viability and germination rates, these plants are now threatened in their native environments. Because of these factors, researchers are investigating micropropagation techniques to optimize phytochemicals in vitro. This review's objective is to offer details on the distribution, phytochemistry, micropropagation, in vitro galanthamine synthesis, and pharmacology which will help to design biotechnological techniques for the preservation, widespread multiplication, and required secondary metabolite production from Crinum spp. KEY POINTS: • Botanical description and phytochemical profile of Crinum spp. • In vitro micropropagation method of Crinum sp. • Bioactive compound galanthamine isolation techniques and its pharmacological properties.

Prediction of In vitro organogenesis of Bacopa monnieri using artificial neural networks and regression models

This study was conducted to determine if artificial neural networks (ANN) can be used to accurately predict in vitro organogenesis of Bacopa monnieri compared with statistical regression. Prediction models were developed for shoot and root organogenesis (outputs) on two culture media (Murashige and Skoog and Gamborg B5) affected by two explant types (leaf and node) and two cytokinins (6-Benzylaminopurine and Thidiazuron at 1.0, 5.0, and 10.0 μM levels) with and without the addition of auxin (1-Naphthaleneacetic acid 0.1 μM) (inputs). Categorical data were encoded in numeric form using one-hot encoding technique. Backpropagation (BP) and Kalman filter (KF) learning algorithms were used to develop nonparametric models between inputs and outputs. Correlations between predicted and observed outputs (validation dataset) were similar in both ANN-BP (R values = 0.77, 0.71, 0.68, and 0.48), and ANN-KF (R values = 0.79, 0.68, 0.75, and 0.49), and were higher than regression (R values = 0.13, 0.48, 0.39, and 0.37) models for shoots and roots from leaf and node explants, respectively. Because ANN models have the ability to interpolate from unseen data, they could be used as an effective tool in accurately predicting the in vitro growth kinetics of Bacopa cultures.

Multiplex knockout of trichome-regulating MYB duplicates in hybrid poplar using a single gRNA

As the focus for CRISPR/Cas-edited plants moves from proof-of-concept to real-world applications, precise gene manipulation will increasingly require concurrent multiplex editing for polygenic traits. A common approach for editing across multiple sites is to design one guide RNA (gRNA) per target; however, this complicates construct assembly and increases the possibility of off-target mutations. In this study, we utilized one gRNA to target MYB186, a known positive trichome regulator, as well as its paralogs MYB138 and MYB38 at a consensus site for mutagenesis in hybrid poplar (Populus tremula × P. alba INRA 717-1B4). Unexpected duplications of MYB186 and MYB138 resulted in eight alleles for the three targeted genes in the hybrid poplar. Deep sequencing and polymerase chain reaction analyses confirmed editing across all eight targets in nearly all of the resultant glabrous mutants, ranging from small indels to large genomic dropouts, with no off-target activity detected at four potential sites. This highlights the effectiveness of a single gRNA targeting conserved exonic regions for multiplex editing. Additionally, cuticular wax and whole-leaf analyses showed a complete absence of triterpenes in the trichomeless mutants, hinting at a previously undescribed role for the nonglandular trichomes of poplar.

Micropropagation of Rare Scutellaria havanensis Jacq. and Preliminary Studies on Antioxidant Capacity and Anti-Cancer Potential

We report the development of in vitro propagation protocols through an adventitious shoot induction pathway for a rare and medicinal Scutellaria havanensis. In vitro propagation studies using nodal explants showed MS medium supplemented with 10 µM 6-Benzylaminopurine induced the highest number of adventitious shoots in a time-dependent manner. A ten-day incubation was optimum for shoot bud induction as longer exposures resulted in hyperhydricity of the explants and shoots induced. We also report preliminary evidence of Agrobacterium tumefaciens EHA105-mediated gene transfer transiently expressing the green fluorescent protein in this species. Transformation studies exhibited amenability of various explant tissues, internode being the most receptive. As the plant has medicinal value, research was carried out to evaluate its potential antioxidant capacity and the efficacy of methanolic leaf extracts in curbing the viability of human colorectal cancer cell line HCT116. Comparative total polyphenol and flavonoid content measurement of fresh and air-dried leaf extract revealed that the fresh leaf extracts contain higher total polyphenol and flavonoid content. The HCT 116 cell viability was assessed by colorimetric assay using a 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide, showed a steady growth inhibition after 24 h of incubation. Scanning electron microscopy of leaf surface revealed a high density of glandular and non-glandular trichomes. This research provides a basis for the conservation of this rare plant and future phytochemical screening and clinical research.

Therapeutic and Medicinal Uses of Terpenes

Terpenes, also known as terpenoids are the largest and most diverse group of naturally occurring compounds. Based on the number of isoprene units they have, they are classified as mono, di, tri, tetra, and sesquiterpenes. They are mostly found in plants and form the major constituent of essential oils from plants. Among the natural products that provide medical benefits for an organism, terpenes play a major and variety of roles. The common plant sources of terpenes are tea, thyme, cannabis, Spanish sage, and citrus fruits (e.g., lemon, orange, mandarin). Terpenes have a wide range of medicinal uses among which antiplasmodial activity is notable as its mechanism of action is similar to the popular antimalarial drug in use—chloroquine. Monoterpenes specifically are widely studied for their antiviral property. With growing incidents of cancer and diabetes in modern world, terpenes also have the potential to serve as anticancer and antidiabetic reagents. Along with these properties, terpenes also allow for flexibility in route of administration and suppression of side effects. Certain terpenes were widely used in natural folk medicine. One such terpene is curcumin which holds anti-inflammatory, antioxidant, anticancer, antiseptic, antiplasmodial, astringent, digestive, diuretic, and many other properties. Curcumin has also become a recent trend in healthy foods and open doors for several medical researches. This chapter summarizes the various terpenes, their sources, medicinal properties, mechanism of action, and the recent studies that are underway for designing terpenes as a lead molecule in the modern medicine.

Functional characterization of 1-aminocyclopropane-1-carboxylic acid oxidase gene in Arabidopsis thaliana and its potential in providing flood tolerance

Ethylene is a phytohormone that has gained importance through its role in stress tolerance and fruit ripening. In our study we evaluated the functional potential of the enzyme involved in ethylene biosynthesis of plants called ACC (aminocyclopropane-1-carboxylic acid) oxidase which converts precursor ACC to ethylene. Studies on ethylene have proven that it is effective in improving the flood tolerance in plants. Thus our goal was to understand the potential of ACC oxidase gene overexpression in providing flood tolerance in transgenic plants. ACC oxidase gene was PCR amplified and inserted into the pBINmgfp5-er vector, under the control of a constitutive Cauliflower Mosaic Virus promoter. GV101 strain of Agrobacterium tumefaciens containing recombinant pBINmgfp5-er vector (referred herein as pBIN-ACC) was used for plant transformation by the 'floral dip' method. The transformants were identified through kanamycin selection and grown till T3 (third transgenic) generation. The flood tolerance was assessed by placing both control and transgenic plants on deep plastic trays filled with tap water that covered the soil surface. Our result shows that wild-type Arabidopsis could not survive more than 20 days under flooding while the transgenic lines survived 35 days, suggesting development of flood tolerance with overexpression of ACC oxidase. Further molecular studies should be done to elucidate the role and pathways of ACC oxidase and other phytohormones involved in the development of flood adaptation.

Application of Bioactive Compounds from Scutellaria in Neurologic Disorders

Inflammation of the brain is one of the most highly researched yet mysterious areas in modern day neurology. The process of inflammation is a normal mechanism of wound healing that can result from acute injuries such as traumas or can be caused by genetic/environmental factors. After the initial insult, the immune system defenses, specifically microglial cells, are activated in order to combat the infection or injury. However, prolonged or chronic inflammation is often deleterious due mainly to accumulation of free reactive oxygen species (ROS) and other pro-inflammatory cytokines in the brain FADDIN EN.CITE. Plant-derived natural compounds have the potential to ameliorate the causes and symptoms of neuroinflammation, due to their various anti-oxidant and anti-inflammatory activities, without completely muting the immune defenses. Scutellaria is a perennial plant in the mint family that has been used to treat diseases in Asia and Eastern Europe throughout history. This chapter reviews the active components of various Scutellaria species and their mechanisms of action to prevent chronic neurologic disorders involving neuroinflammation and neurodegeneration.

Effect of light, methyl jasmonate and cyclodextrin on production of phenolic compounds in hairy root cultures of Scutellaria lateriflora

Scutellaria lateriflora (American skullcap) has been used in traditional medicine to treat several medical conditions including nervous disorders and cancer. Previous studies have associated these medicinal properties to flavones present in roots and leaves of this species. In order to develop a production system and study the biosynthesis of these bioactive compounds, hairy root cultures of S. lateriflora were established and line 4 was selected for further studies based on its growth performance in a modified Murashige and Skoog's medium supplemented with 0.5mg/l indole-3-butyric acid. Scanning electron microscopy of the hairy roots showed a high profusion of hairs along the root. Several phenolic compounds, including verbascoside, and the flavones wogonin, baicalein, scutellarein and their respective glucuronides were identified by high performance liquid chromatography-tandem mass spectrometry in the root tissue, but not in the culture medium. Among these compounds, verbascoside accumulated at the highest levels. Interestingly, cultures incubated under continuous light and treated with 15mM methyl-β-cyclodextrin for 24h produced significantly higher levels of the aglycones, baicalein and wogonin, but not scutellarein, compared to cultures incubated under continuous darkness. This work demonstrates that hairy root cultures of S. lateriflora have the biosynthetic capacity to produce known Scutellaria flavones and suggest that light may have a selected regulatory effect on the synthesis or accumulation of these phenolic compounds.

Delayed growth of glioma by Scutellaria flavonoids involve inhibition of Akt, GSK-3 and NF-κB signaling

Plants of the genus Scutellaria constitute one of the common components of Eastern as well as traditional American medicine against various human diseases, including cancer. In this study, we examined the in vivo anti-glioma activity of a leaf extract of Scutellaria ocmulgee (SocL) while also exploring their potential molecular mechanisms of action. Oral administration of SocL extract delayed the growth of F98 glioma in F344 rats, both in intracranial and subcutaneous tumor models. Immunohistochemistry revealed inhibition of Akt, GSK-3α/β and NF-κB phosphorylation in the subcutaneous tumors following treatment with Scutellaria. The SocL extract as well as the constituent flavonoid wogonin also showed dose- and time-dependent inhibition of Akt, GSK-3α/β and NF-κB in F98 cell cultures in vitro, as determined by western blot analysis. Pharmacologic inhibitors of PI3K and NF-κB also significantly inhibited the in vitro proliferation of F98 glioma cells, indicating the key role of these signaling molecules in the growth of malignant gliomas. Transfection of F98 cells with constitutively active mutant of AKT (AKT/CA), however, did not significantly reverse Scutellaria-mediated inhibition of proliferation, indicating that Scutellaria flavonoids either directly inhibited Akt kinase activity or acted downstream of Akt. In vitro Akt kinase assay demonstrated that the SocL extract or wogonin could indeed bind to Akt and inhibit its kinase activity. This study provides the first in vivo evidence and mechanistic support for anti-glioma activity of Scutellaria flavonoids and has implications in potential usage of Scutellaria flavonoids in adjuvant therapy for malignant tumors, including gliomas.

In vitro antitumor mechanisms of various Scutellaria extracts and constituent flavonoids

Scutellaria is a traditional herbal remedy with potential anti-cancer activity. The purpose of this study was to evaluate anticancer mechanisms of thirteen Scutellaria species and analyze their leaf, stem and root extracts for levels of common biologically active flavonoids: apigenin, baicalein, baicalin, chrysin, scutellarein, and wogonin. Malignant glioma, breast carcinoma and prostate cancer cells were used to determine tumor-specific effects of Scutellaria on cell proliferation, apoptosis and cell cycle progression, via the MTT assay and flow cytometry-based apoptosis and cell cycle analysis. The extracts and individual flavonoids inhibited the proliferation of malignant glioma and breast carcinoma cells without affecting primary or non-malignant cells. The flavonoids exhibited different mechanisms of anti-tumor activity as well as positive interactions. The antitumor mechanisms involved induction of apoptosis and cell cycle arrest at G1/G2. Of the extracts tested, leaf extracts of S. angulosa, S. integrifolia, S. ocmulgee and S. scandens were found to have strong anticancer activity. This study provides basis for further mechanistic and translational studies into adjuvant therapy of malignant tumors using Scutellaria leaf tissues.

Transferrin-facilitated lipofection gene delivery strategy: characterization of the transfection complexes and intracellular trafficking

We previously showed that mixing transferrin with a cationic liposome prior to the addition of DNA, greatly enhanced the lipofection efficiency. Here, we report characterization of the transfection complexes in formulations prepared with transferrin, lipofectin, and DNA (pCMVlacZ) in various formulations. DNA in all the formulations that contain lipofectin was resistant to DNase I treatment. Transfection experiments performed in Panc 1 cells showed that the standard formulation, which was prepared by adding DNA to a mixture of transferrin and lipofectin, yielded highest transfection efficiency. There was no apparent difference in zeta potential among these formulations, but the most efficient formulation contained complexes with a mean diameter of three to four times that of liposome and the complexes in other gene delivery formulations. Transmission electron microscopic examination of the standard transfection complexes formulated using gold-labeled transferrin showed extended circular DNA decorated with transferrin as compared to extensively condensed DNA found in lipofectin-DNA complexes and heterogeneous structures in other formulations. By confocal microscopy, DNA and transferrin were found to colocalize at the perinuclear space and in the nucleus, suggesting cotransportation intracellularly, including nuclear transport. We propose that transferrin enhances the transfection efficiency of the standard lipofection formulation by preventing DNA condensation, and facilitating endocytosis and nuclear targeting.

Development of monoclonal antibodies against bovine mucin core 2 beta6 N-acetylglucosaminyltransferase

Molecular cloning techniques have been used to produce abundant amounts of recombinant glycosyltransferases for biochemical studies. We recently cloned a cDNA which encoded bovine mucin core 2 beta6N-acetylglucosaminyl transferase (C2TF). Poly-histidine-C2TF fusion protein was generated from the cloned cDNA in the E. coli Xpress system and used to produce monoclonal antibodies (MAbs). We obtained seven hybridomas which secreted MAbs against bovine C2TF in mouse ascites with titers ranging from 1:1280 to 1:40960 as assessed by immunofluorescence assay (IF). Isotyping revealed that all seven MAbs were IgG (4 IgG1, 2 IgG2b and 1 IgG2a). The affinity constants (M(-1)) for these MAbs range from 5.4 x 10(7) to 1.2 x 10(9). These MAbs recognized bovine C2TF in tissue sections and on Western blottings. Six of these MAbs reacted with human core 2-M enzyme and one with both core 2-L and core 2-M enzymes on Western blottings. Therefore, these antibodies should be useful for further study of bovine and human core 2 enzymes.

Isolation and characterization of a water stress-specific genomic gene, pwsi 18, from rice

One of the water stress-specific cDNA clones of rice characterised previously, wsi18, was selected for further study. The wsi18 gene can be induced by water stress conditions such as mannitol, NaCl, and dryness, but not by ABA, cold, or heat. A genomic clone for wsi18, pwsi18, contained about 1.7 kbp of the 5' upstream sequence, two introns, and the full coding sequence. The 5'-upstream sequence of pwsi18 contained putative cis-acting elements, namely an ABA-responsive element (ABRE), three G-boxes, three E-boxes, a MEF-2 sequence, four direct and two inverted repeats, and four sequences similar to DRE, which is involved in the dehydration response of Arabidopsis genes. The gusA reporter gene under the control of the pwsi18 promoter showed transient expression in response to water stress. Deletion of the downstream DRE-like sequence between the distal G-boxes-2 and -3 resulted in rather low GUS expression.

Induction of chilling resistance by water stress, and cDNA sequence analysis and expression of water stress-regulated genes in rice

Exposure of seedlings of a chilling-sensitive variety of rice (Oryza sativa L. cv. Wasetoittu) to water stress (0.5 M mannitol, 30 min) at room temperature induced a degree of chilling resistance. No such resistance was induced by exogenous abscisic acid (ABA) application (10 microM, 60 min). Upon short-term water stress, new transcripts were expressed in both seedlings and suspension-cultured cells. We suggest that the genes induced by short-term water stress, and not those induced by ABA, are related to acquired chilling resistance in this chilling-sensitive rice variety. A total of nine different cDNA clones, specifically induced by short-term water stress, were isolated by differential hybridization and partial sequencing. Northern hybridization analysis using RNAs from the seedlings subjected to chilling after water stress treatment reveal three distinct groups of above mentioned nine cDNA clones: wsi (water stress-induced) 18, 76, and 724, representative of genes whose expression increases, decreases, and remains almost fixed during chilling, respectively. The nucleotide and deduced amino acid sequences of the three representative clones were determined. Characteristic features of wsi18 are the presence of one set of amino acid sequence repeats, a conserved amino acid sequence common to LEA-group genes in the N-terminal region, and an alanine- and lysine-rich tract in the C-terminal region.