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Nutraceuticals and Functional Foods
Published in Robert E.C. Wildman, Richard S. Bruno, Handbook of Nutraceuticals and Functional Foods, 2019
The malonic acid pathway begins with acetyl CoA. Meanwhile, in the shikimic pathway, simple carbohydrate intermediates of glycolysis and the pentose phosphate pathway (PPP) are used to form the aromatic amino acids phenylalanine and tyrosine. A third aromatic amino acid, tryptophan, is also a derivative of this pathway. As animals do not possess the shikimic acid pathway, these aromatic amino acids are diet essentials. Obviously, these amino acids are considered primary metabolites or products. Thus, it is the reactions beyond the formation of these amino acids that are of greater importance to the production of secondary metabolites. Once formed, phenylalanine can be used to generate flavonoids (Figure 1.7). The reaction that generates cinnamic acid from phenylalanine is catalyzed by one of the most-studied enzymes associated with secondary metabolites, phenylalanine ammonia lyase (PAL). The expression of PAL is increased during fungal infestation and other stimuli, which may be critical to the plant.
Biocatalytic Nanoreactors for Medical Purposes
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Oscar González-Davis, Chauhan Kanchan, Rafael Vazquez-Duhalt
Phenylketonuria is an inborn error of amino acid metabolism caused by phenylalanine hydroxylase deficiency (Kim et al., 2004). Phenylalanine hydroxylase is a non-heme, iron-containing protein that catalyzes the conversion of phenylalanine to tyrosine and is responsible for the catabolism of most of the dietary phenylalanine. In addition to phenylalanine hydroxylase, phenylalanine ammonia-lyase from plants is being developed for the treatment of Phenylketonuria. This plant enzyme has some advantages when compared with phenylalanine hydroxylase: It does not require cofactors for degrading phenylalanine, the product trans-cinnamic acid is converted to benzoic acid in the liver, which is then excreted via the urine, and it is more stable (Hosking and Gray, 1982).
Separation and Isolation of Plant Constituents
Published in Ravindra Kumar Pandey, Shiv Shankar Shukla, Amber Vyas, Vishal Jain, Parag Jain, Shailendra Saraf, Fingerprinting Analysis and Quality Control Methods of Herbal Medicines, 2018
Ravindra Kumar Pandey, Shiv Shankar Shukla, Amber Vyas, Vishal Jain, Parag Jain, Shailendra Saraf
Phenolics, phenols or polyphenolics are chemical components that occur ubiquitously as natural color pigments responsible for the color of fruits of plants. Phenolics in plants are mostly synthesized from phenylalanine via the action of phenylalanine ammonia lyase (PAL). Phenolics essentially represent a host of natural antioxidants, used as nutraceuticals, found in apples, green tea, and red wine, for their enormous ability to combat cancer, are also thought to prevent heart ailments to an appreciable degree, and sometimes are anti-inflammatory agents (Heinrich et al., 2004).
Interactive effects of zinc oxide nano particles and different light regimes on growth and silymarin biosynthesis in callus cultures of Silybum marianum L.
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2021
Muhammad aamir Shehzad, Mubarak Ali Khan, Amir Ali, Sher Mohammad, Ahmed Noureldeen, Hadeer Darwish, Asif Ali, Ayaz Ahmad, Tariq Khan, Raham Sher Khan
Phenylalanine ammonia-lyase (PAL) activity was determined by the cinnamic acid method developed by Syklowska-Baranek et al. [26]. Initially, Fresh callus (50 mg) was homogenized in 0.8 mM Mercaptoethanol, 0.05 M Tris-HCl buffer and 1% (w/v) PVP under a control PH (8). Thereafter, the solution was filtered and centrifuged at 4 °C for 15 min at 14000 g and supernatant was collected for further assay. The solution used to determine PAL activity contained 1 ml tris-HCL buffer, 0.5 ml/L Phe (10 mM) and 0.1 ml enzymatic extract. After an hour 0.1 ml HCL was used to stop the reaction, after incubating the solution at 37 °C and at 290 nm absorbance was measured. The methodology of Ali et al. [24] was followed for the determination of DPPH free radical scavenging activity. Nonetheless, the methodology of Kazmi et al. [27] was used to examine the superoxide dismutase activity (SOD) in the selected plant samples.
Silver nanoparticles elicited in vitro callus cultures for accumulation of biomass and secondary metabolites in Caralluma tuberculata
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Amir Ali, Sher Mohammad, Mubarak Ali Khan, Naveed Iqbal Raja, Mohammad Arif, Atif Kamil, Zia-ur-Rehman Mashwani
For the determination of PAL activity in the selected callus samples, the procedure of Khan et al. [15] was adopted. For this purpose, about 80–100 mg of each sample was first homogenized using ice-cold buffer of potassium borate (BK3O3) at a concentration of 100 mM, maintained at 8.8 pH in combo with 2 mM mercaptoethanol and finally centrifuged at 12,000 rpm for 10 min at 4◦C. Thereafter, the obtained supernatant was employed for the PAL assay. The reaction mixture was adjusted by the addition of 0.5 ml of the extract of each selected sample in a tube already filled up with 0.5 ml of phenylalanine (con: 4.0 mM−1) and 1.0 ml of potassium borate (BK3O3) buffer (con: 100 mM; pH 8.8). Exactly 2.0 ml of the reaction mixture was incubated at 30 °C and was supplemented with 0.2 ml of 6 M HCl. After half an hour (30 min) the absorbance was taken at 290 nm. Absorbance of the reaction mixture was considered as function of the formation of enzyme product. It was proposed that, one unit of the phenylalanine ammonia lyase activity (U) is the amount of absorbance variation of 0.01.
ARTIFICIAL CELL evolves into nanomedicine, biotherapeutics, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, cell/stem cell therapy, nanoparticles, liposomes, bioencapsulation, replicating synthetic cells, cell encapsulation/scaffold, biosorbent/immunosorbent haemoperfusion/plasmapheresis, regenerative medicine, encapsulated microbe, nanobiotechnology, nanotechnology
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Some conditions like inborn errors of metabolism require administration throughout the life of the person. Instead of injections, orally administered artificial cells can act as they move down the intestine, then excreted without accumulation in the body (Figure 5). For example, Chang found that oral artificial cells containing urease and ammonia adsorbent can lower the systemic urea level [6]. This leads to NIH supported development by Kjellstrand’s group leading to clinical trials in patients [58]. Our study shows that artificial cells containing xanthine oxidase lower the toxic systemic hypoxanthine levels in an infant with Lesch–Nyhan Disease [52]. Bourget and Chang show that orally administered artificial cells containing phenylalanine ammonia lyase (PAL) lower the systemic phenylalanine levels in phenylketonuria (PKU) rats and improved the growth of the animals [53]. Following my usual policy, I seek an expert, Scriver in Phenylketonuria [59] and also a company to develop this for clinical use. They, in turn, collaborate with another company and develop an injectable PEG-PAL that has just been approved for use in patients [57]. In order to avoid long term injection, they are now returning to look at doing this by oral administration [60]. In the same way, our study shows that oral artificial cells containing tyrosinase when given orally lowers the systemic tyrosine level [9]. Kaminsky et al. use argocytes containing enzyme nanoparticles to reduce toxic concentrations of arginine in the blood [61]. Abed et al. reported in 2018 the use of Lysozyme and DNAse I loaded poly (D, L lactide-co-caprolactone) nanocapsules as an oral delivery system [42].