Levodopa in Mucuna pruriens and its degradation

Spherical porous iron-nitrogen-carbon nanozymes derived from a tannin coordination framework for the preparation of L-DOPA by emulating tyrosine hydroxylase

L-3,4-Dihydroxyphenylalanine (L-DOPA) is widely used in Parkinson's disease treatment and is therefore in high demand. Development of an efficient method for the production of L-DOPA is urgently required. Nanozymes emulating tyrosine hydroxylase have attracted enormous attention for biomimetic synthesis of L-DOPA, but suffered from heterogeneity. Herein, a spherical porous iron-nitrogen-carbon nanozyme was developed for production of L-DOPA. Tannic acid chelated with ferrous ions to form a tannin-iron coordination framework as a carbon precursor. Iron and nitrogen co-doped carbon nanospheres were assembled via an evaporation-induced self-assembly process using urea as a nitrogen source, F127 as a soft template, and formaldehyde as a crosslinker. The nanozyme was obtained after carbonization and acid etching. The nanozyme possessed a dispersive iron atom anchored in the Fe-N coordination structure as an active site to mimic the active center of tyrosine hydroxylase. The material showed spherical morphology, uniform size, high specific surface area, a mesoporous structure and easy magnetic separation. The structural properties could promote the density and accessibility of active sites and facilitate mass transport and electron transfer. The nanozyme exhibited high activity to catalyze the hydroxylation of tyrosine to L-DOPA as tyrosine hydroxylase in the presence of ascorbic acid and hydrogen peroxide. The titer of DOPA reached 1.2 mM. The nanozyme showed good reusability and comparable enzyme kinetics to tyrosine hydroxylase with a Michaelis-Menten constant of 2.3 mM. The major active species was the hydroxyl radical. Biomimetic simulation of tyrosine hydroxylase using a nanozyme with a fine structure provided a new route for the efficient production of L-DOPA.

A validated LC-MS/MS method for quantitative determination of L-dopa in Fagioli di Sarconi beans (Phaseolus vulgaris L.)

An analytical method based on ultrasound assisted extraction (UAE) and liquid chromatography coupled to electrospray tandem mass spectrometry (LC-ESI/MS/MS) was validated and applied for determining L-dopa in four ecotypes of Fagioli di Sarconi beans (Phaseolus vulgaris L.), marked with the European label PGI (Protected Geographical Indication). The selectivity of the proposed method was ensured by the specific fragmentation of the analyte. Simple isocratic chromatographic conditions and mass spectrometric detection in multiple reaction monitoring (MRM) acquisition mode were used for sensitive quantification. The LC-ESI/MS/MS method was validated within a linear range of 0.001-5.000 μg/mL. Values of 0.4 and 1.1 ng/mL were obtained for the limits of detection and quantification, respectively. The repeatability, inter-day precision, and recovery values ranges were 0.6%-4.5%, 5.4%-9.9%, and 83%-93%, respectively. Fresh and dried beans, as well as pods, cultivated exclusively with organic methods avoiding any synthetic fertilizers and pesticides were analyzed showing an L-dopa content ranging from 0.020 ± 0.005 to 2.34 ± 0.05 μg/g dry weight.

Dietary supplementation of low levels of unprocessed Mucuna pruriens utilis seed meal induces mild antinutritional entero-physio-metabolic perturbations without compromising performance and meat quality in finisher broilers

The rapidly growing world human population accentuates the need for improved production especially of protein-rich food. Broiler meat production offers opportunity to ensure security of this food. However, the production of modern broilers is not only limited by high feed costs due to dietary use of expensive energy and protein sources but also their meat possesses undesirable quality attributes. This study thus examined the effect of dietary Mucuna pruriens utilis seed meal (MSM) on growth performance, blood profile, carcass traits, and meat quality in finisher broiler chickens. In a completely randomised design (CRD), 320 21-day-old chicks were randomly allocated to 32 pens in which they were allotted 4 dietary treatments with 0, 2.5, 5, and 10% MSM, each with 8 replicate pens of 10 birds, for 28 days. Growth performance, carcass characteristics, internal organs, haemato-biochemistry, and meat quality were measured. Results showed that dietary MSM did not affect (P > 0.05) broiler performance, weights, and lengths of carcass cuts and internal organs, haematology, and meat quality. The only exception was MSM-induced increase in duodenal weight (linear, P < 0.05) and serum phosphorus (quadratic, P = 0.05) in contrast to a decrease in procalcitonin (quadratic, P < 0.01) and serum levels of total protein (linear, P < 0.05; and quadratic, P < 0.01), albumin (quadratic, P < 0.05), and bilirubin (quadratic, P = 0.001). Therefore, MSM could be supplemented up to 10% without compromising performance, carcass traits, internal organs, haemato-biochemistry, and meat quality in finisher broiler diets.

The neuroprotective effect of traditional Chinese medicinal plants-A critical review

Neurodegenerative and neuropsychiatric diseases are increasingly affecting individuals' quality of life, thus increasing their cost to social and health systems. These diseases have overlapping mechanisms, such as oxidative stress, protein aggregation, neuroinflammation, neurotransmission impairment, mitochondrial dysfunction, and excitotoxicity. Currently, there is no cure for neurodegenerative diseases, and the available therapies have adverse effects and low efficacy. For neuropsychiatric disorders, such as depression, the current therapies are not adequate to one-third of the patients, the so-called treatment-resistant patients. So, searching for new treatments is fundamental. Medicinal plants appear as a strong alternative and complement towards new treatment protocols, as they have been used for health purposes for thousands of years. Thus, the main goal of this review is to revisit the neuroprotective potential of some of the most predominant medicinal plants (and one fungus) used in traditional Chinese medicine (TCM), focusing on their proven mechanisms of action and their chemical compositions, to give clues on how they can be useful against neurodegeneration progression.

Protective effect of Mucuna pruriens (L.) DC. var. pruriens seed extract on apoptotic germ cells in ethanolic male rats

Thai Mucuna pruriens (L.) DC. var pruriens (T-MP) seed containing levodopa (L-DOPA) and antioxidant capacity has been shown to improve sexual behavior and male reproductive parameters in rats treated with ethanol (Eth). However, its protective effect on testicular apoptotic germ cells has never been reported. This study aimed to investigate the potential effects of T-MP seed extract on expressions of caspase, proliferating cell nuclear antigen (PCNA), and dopamine D2 receptor (D2R) proteins in Eth rats. Thirty-six male Wistar rats were divided into four groups (9 animals/group), including control, Eth, T-MP150+Eth, and T-MP300+Eth, respectively. Control rats received distilled water, and Eth rats received Eth (3g/kg BW; 40%v/v). The T-MP groups were treated with T-MP seed extract at a dose of 150 or 300 mg/kg before Eth administration for 56 consecutive days. The results showed that the seminiferous tubule diameter and epithelial height were significantly increased in both T-MP treated groups compared to the Eth group. Additionally, the caspase-9 and -3, and PCNA expressions were decreased, but D2R expression was markedly increased in T-MP groups. It was concluded that T-MP seed extract could protect testicular apoptosis induced by Eth via changes in caspase, PCNA, and D2R protein expressions.

'Sharpshooter' in Botanic Garden: the tale of a rare plant-insect interaction

Here we report a unique plant-insect interaction between the leafhopper Aloka depressa (tribe Phlogisini) and the host liana, Diploclisia glaucescens, from a Botanic Garden located at the southern edge of Western Ghats in India. Field observations and SEM micrographs were employed to derive evidences on this rare plant-insect interaction. 20-Hydroxyecdysone (20E), insect moulting hormone, was detected and quantified in the host plant D. glaucescens using HPTLC-densitometry. 20E was isolated and characterized from D. glaucescens using column chromatography, 1H-, 13C-NMR and HR-MS. 20E was also detected in A. depressa excrement using HPTLC-densitometry. The leafhopper A. depressa is functioning as a 'sharpshooter' drawing nutrients from the host liana, D. glaucescens, and flinging the waste fluid as droplets through their tail ends. SEM micrographs of A. depressa revealed its external morphological features, characteristic of a sharpshooter. We quantified 20E (0.44-1.44%, dry wt.) in various parts of D. glaucescens. 20E (1.47%, dry wt.) was also detected in the excrement of A. depressa. This plant (D. glaucescens)-insect (A. depressa) association crucially is not damaging the host liana. Considering the diseases caused by sharpshooting leafhoppers in the Americas, this association and the survival of the host plant (D. glaucescens) is illustrating a unique plant-insect interaction.

Nutritional and pharmacological potentials of orphan legumes: Subfamily faboideae

Legumes are a major food crop in many developing nations. However, orphan or underutilized legumes are domesticated legumes that have valuable properties but are less significant than main legumes due to use and supply restrictions. Compared to other major legumes, they are better suited to harsh soil and climate conditions, and their great tolerance to abiotic environmental circumstances like drought can help to lessen the strains brought on by climate change. Despite this, their economic significance in international markets is relatively minimal. This article is aimed at carrying out a comprehensive review of the nutritional and pharmacological benefits of orphan legumes from eight genera in the sub-family Faboidea, namely Psophocarpus Neck. ex DC., Tylosema (Schweinf.) Torre Hillc., Vigna Savi., Vicia L., Baphia Afzel. ex G. Lodd., Mucuna Adans, Indigofera L. and Macrotyloma (Wight & Arn.) Verdc, and the phytoconstituents that have been isolated and characterized from these plants. A literature search was conducted using PubMed, Google Scholar, and Science Direct for articles that have previously reported the relevance of underutilized legumes. The International Union for Conservation of Nature (IUCN) red list of threatened species was also conducted for the status of the species. References were scrutinized and citation searches were performed on the study. The review showed that many underutilized legumes have a lot of untapped potential in terms of their nutritional and pharmacological activities. The phytoconstituents from plants in the subfamily Faboideae could serve as lead compounds for drug discovery for the treatment of a variety of disorders, indicating the need to explore these plant species.

Development and Validation of a Reversed-Phase HPLC Method with UV Detection for the Determination of L-Dopa in Vicia faba L. Broad Beans

L-Dopa (LD), a substance used medically in the treatment of Parkinson’s disease, is found in several natural products, such as Vicia faba L., also known as broad beans. Due to its low chemical stability, LD analysis in plant matrices requires an appropriate optimization of the chosen analytical method to obtain reliable results. This work proposes an HPLC-UV method, validated according to EURACHEM guidelines as regards linearity, limits of detection and quantification, precision, accuracy, and matrix effect. The LD extraction was studied by evaluating its aqueous stability over 3 months. The best chromatographic conditions were found by systematically testing several C18 stationary phases and acidic mobile phases. In addition, the assessment of the best storage treatment of Vicia faba L. broad beans able to preserve a high LD content was performed. The best LD determination conditions include sun-drying storage, extraction in HCl 0.1 M, chromatographic separation with a Discovery C18 column, 250 × 4.6 mm, 5 µm particle size, and 99% formic acid 0.2% v/v and 1% methanol as the mobile phase. The optimized method proposed here overcomes the problems linked to LD stability and separation, thus contributing to the improvement of its analytical determination.

Levodopa Content of Mucuna pruriens Supplements in the NIH Dietary Supplement Label Database

This case series assesses the levels of levodopa in Mucuna pruriens supplements available in the US that are included in the National Institutes of Health Dietary Supplement Label Database.

Physico-chemical characteristics and cytotoxicity evaluation of CuO and TiO2 nanoparticles biosynthesized using extracts of Mucuna pruriens utilis seeds

The green synthesis approach to nanoparticles has been widely received as an alternative to the conventional methods, specifically for applications in areas such as biology, agriculture and medicine, where toxicity is of great concern. In this study, copper oxide (CuO) and titanium oxide (TiO₂) nanoparticles (NPs) were synthesized using an aqueous extract of Mucuna pruriens utilis seed. The morphology and structural characterization of the NPs were achieved by using scanning and transmission electron microscopy (SEM and TEM), and X-ray diffraction (XRD) measurement, while the elemental composition was studied using electron diffraction X-ray spectroscopy (EDS). A monoclinic phase of CuO and anatase phases of TiO₂ with high crystallinity were confirmed from the diffraction patterns of the XRD. Both TEM and SEM micrographs of the CuO confirmed short rod-shaped nanostructure, while spherical morphologies were obtained for the TiO₂ NPs. The EDS study indicated that the composition of the samples conformed with the identified products in the XRD and attest to the purity of the NPs. The nanoparticles exhibited a dose-dependent profile in MTT cytotoxicity assay with some cell specificity. However, the anticancer potential of these NPs was still lower than that of the standard anticancer drug, 5-fluorouracil.

Development of Jelly Loaded with Nanogel Containing Natural L-Dopa from Mucuna pruriens Seed Extract for Neuroprotection in Parkinson’s Disease

The first line therapy of patients with Parkinson’s disease, a neurodegenerative disorder caused by the degeneration of dopaminergic neurons, is levodopa (L-dopa) given orally. Recently, the presence of natural L-dopa in the seed of Mucuna pruriens, a tropical legume in the Fabaceae family, was reported and it showed superior efficiency compared with synthetic L-dopa. Therefore, this study aimed to examine the phytochemical compounds, particularly for natural L-dopa, in M. pruriens seed extract and subsequently prepare a nanogel containing the extract prior to incorporation into a jelly formulation for use as a functional food in elderly patients with Parkinson’s disease. The results show that M. pruriens seed extract contains phenolic compounds, flavonoids, tannins, alkaloids, terpenoids, and saponins. The quantitative analysis performed by the HPLC method revealed that spray-dried M. pruriens seed extract contained 5.59 ± 0.21% L-dopa. M. pruriens seed extract possesses a ferric-reducing antioxidant power and shows free-radical scavenging activity, determined by DPPH and ABTS methods, suggesting a distinctive antioxidant ability of the extract. M. pruriens seed extract at 10 ng/mL did not show cytotoxicity against a neuronal cell line (SH-SY5Y cells), kidney cells (HEK293 cells), or Caco-2 cells. Nanogel of M. pruriens seed extract prepared by ionic gelation had the hydrodynamic diameter, polydispersity index and zeta potential value of 384.53 ± 11.24 nm, 0.38 ± 0.05, and −11.23 ± 1.15 mV, respectively. The transepithelial transport of L-dopa in M. pruriens seed-extract nanogel through Caco-2 cells was measured. Nanogel containing M. pruriens seed extract at the concentration of 10 ng/mL exhibited neuroprotective activity. A jelly formulation containing M. pruriens seed-extract nanogel was successfully developed. The prepared jelly exhibited the acceptable physical and microbiological stabilities upon 6 months of the stability test. The half-life of natural L-dopa in jelly were 3.2, 0.9, and 0.6 years for storage conditions at 4, 30, and 40 °C, respectively, indicating the thermal degradation of natural L-dopa. The prepared jelly containing natural L-dopa from M. pruriens seed extract with the prominent antioxidant activity is a promising option for elderly patients suffering from Parkinson’s disease.

Assessment of major centelloside ratios in Centella asiatica accessions grown under identical ecological conditions, bioconversion clues and identification of elite lines

Centellosides viz., asiatic acid, madecassic acid, asiaticoside, madecassoside, are the major bioactive molecules in Centella asiatica. In this study madecassic acid:asiatic acid, madecassoside:asiaticoside (C6-hydroxylation versus non-hydroxylation) and asiaticoside:asiatic acid, madecassoside:madecassic acid (C28-glycoside versus aglycone) ratios in 50 C. asiatica accessions originally collected from their natural habitats in south India and grown under identical ecological conditions for six generations were determined using validated HPTLC-densitometry protocols. Asiatic acid, madecassic acid, asiaticoside and madecassoside contents ranged from 0.00-0.29% (average 0.03 ± 0.06%; 28 accessions recorded asiatic acid content as zero), 0.02-0.72% (0.12 ± 0.13%), 0.04-2.41% (0.44 ± 0.52%) and 0.15-5.27% (1.59 ± 1.26%), respectively. Distinctly, C6-hydroxylated (madecassic acid:asiatic acid 4.00, madecassoside:asiaticoside 3.61) and C28-glycosylated (asiaticoside:asiatic acid 14.67, madecassoside: madecassic acid 13.25) centellosides dominated over the respective non-derivatized entities. Our results infer that both C6-hydroxylation by CYP450-dependent monooxygenases and C28-glycosylation by UDP-Glc glucosyltransferases are dominant bioconversion steps in C. asiatica. Besides, this study discovered six elite lines of C. asiatica, with their (asiaticoside + madecassoside) contents above the industrial benchmark (≥ 4%) from south India. Two elite clones with asiaticoside contents ≥ 2% were also identified. Standardization of the agrotechniques of these elite lines could lead to their industrial applications. Further, this study emphasizes the need for standardizing all four centellosides as biomarkers in C. asiatica raw drugs, pharmaceutical and cosmetic products.

Therapeutic potential of Mucuna pruriens (Linn.) on high-fat diet-induced testicular and sperm damage in rats

Objective

Mucuna pruriens Linn., a leguminous plant, is identified as a herbal medicine for improving fertility-related disorders in the alternative and complementary systems of medicine. The study was focused on evaluating the therapeutic potential of M. pruriens on testis and sperm parameters in a high-fat-induced hypercholesterolemia model.

Materials and Methods

Male rats were divided as normal-control rats (NCR); normal-control rats + M.pruriens (200 mg/kg b.w. of ethanolic extract of M. pruriens seed) treated (NCRD); hypercholesterolemic rats (HCR) and hypercholesterolemic rats + M. pruriens (HCRD). Groups were further divided into three post-exposure periods (subgroups) of 9, 18, and 36 days, and the progressive changes in testis histology and sperm were analyzed.

Results

The study showed a significant impairment in testicular histoarchitecture, depletion of antioxidant enzyme levels, increased oxidative stress and lipid peroxidation in the HCR group. The study indicated severe structural and functional damage in sperm parameters and diminished chromatin integrity in the HCR group. In the HCR rats, the follicular stimulating hormone (FSH) and luteinizing hormone (LH) and testosterone were significantly reduced. There was a significant improvement in sperm parameters and testis histology in the HCRD group.

Conclusion

The study reveals the potential efficacy of M. pruriens to improve spermatogenesis, sperm parameters and hormone levels in hypercholesterolemic rats.

Polyphenol oxidase (PPO) arm of catecholamine pathway catalyzes the conversion of L-tyrosine to L-DOPA in Mucuna pruriens (L.) DC var. pruriens: An integrated pathway analysis using field grown and in vitro callus cultures

Mucuna pruriens (L.) DC var. pruriens is the natural source for _L-DOPA, precursor of the neurotransmitter dopamine, used widely in the treatment of Parkinson's disease. However, _L-DOPA synthesis in plants is mediated either by Catecholamine (CA) pathway or alternate pathway catalyzed by Cytochrome P450 (CYP450) class of enzymes. Interestingly, the CA pathway itself can be initiated either by tyrosine hydroxylase (TH) or polyphenol oxidase (PPO). The CA pathway mediated synthesis of _L-DOPA has not yet been proved in M. pruriens albeit strong indications. Therefore, the present investigation is focused on metabolite analysis of major intermediates of CA pathway up to the formation of dopamine and expression analysis of the selected genes, in different tissues and callus cultures. The four major intermediates, _L-tyrosine, tyramine, _L-DOPA and dopamine, were detected using NMR spectroscopy and quantified by HPLC in the callus cultures and in different tissues of the field plant, respectively. The various stages of leaf tissue were also analyzed for metabolite profiling. The relative amount of intermediates detected during the ontogeny of leaf indicates that PPO mediated conversion of _L-tyrosine to dopamine through _L-DOPA is relatively higher compared to dopamine production from tyramine. Among the two possible enzymes, activity of PPO was 6.5-fold more than TH in metabolically active young leaves compared to intermediate leaves. The gene expression profiles comprising upstream genes of _L-tyrosine synthesis and downstream up to dopamine synthesis shows strong correlation with _L-DOPA synthesis. The study validates CA pathway mediated synthesis of _L-DOPA with PPO as candidate enzyme, in M. pruriens.

Mucuna pruriens (L.) DC. seed extract inhibits lipopolysaccharide-induced inflammatory responses in BV2 microglial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammation caused by activated microglia is known to be associated with neurodegenerative diseases, e.g., Parkinson's disease (PD) and Alzheimer's disease (AD). Inhibiting the inflammatory process can be considered a potential strategy for the treatment of inflammation-associated diseases. Mucuna pruriens (L.) DC. (Leguminosae) has long been used in Thailand, India, China and other tropical countries to treat several diseases including PD. M. pruriens seeds have been found to possess a variety of pharmacological properties including antioxidant and anti-Parkinsonism effects. However, the anti-inflammatory effects of M. pruriens seeds during microglial activation have yet to be reported.

AIM OF THE STUDY

The present study was performed to evaluate the anti-inflammatory effects of M. pruriens seed extract and elucidate its underlying mechanism using lipopolysaccharide (LPS)-stimulated BV2 microglial cells.

MATERIALS AND METHODS

BV2 microglial cells were pretreated with various concentrations of M. pruriens seed extract before being stimulated with LPS. The levels of inflammatory mediators were analyzed by Griess assay and enzyme-linked immunoassay (ELISA). The protein expression levels of inflammatory cytokines were determined by Western blot analysis. The translocation of nuclear factor-kappa B (NF-κB) was assessed by immunofluorescence microscopy.

RESULTS

M. pruriens seed extract significantly inhibited the release of inflammatory mediators including nitric oxide (NO), IL-1β, IL-6, and TNF-α in LPS-stimulated BV2 microglial cells. The extract also decreased the protein expression of IL-1β, IL-6, and TNF-α. Moreover, M. pruriens seed extract inhibited the translocation of NF-κB.

CONCLUSIONS

M. pruriens seed extract could suppress inflammatory responses in LPS-activated BV2 microglial cells by inhibiting the NF-κB signaling pathway. These findings support the use of M. pruriens seeds in traditional and alternative medicine for the treatment of PD and other inflammation-associated diseases.

Optimization of extraction techniques and RP-HPLC analysis of anti-parkinson drug levodopa from flowers of Vicia faba L

Vicia faba, also known as “bakla” in Turkey, is a species of Fabaceae family that is widely grown in Africa and Asia. It is rich in levodopa, a medicinal substance used to treat Parkinson's disease. Levodopa produced by chemical synthesis is expensive and causes various side effects. Therefore, it is recommended to use natural levodopa sources to prevent possible side effects. A Central Composite Design technique has been used in this study to optimize levodopa extraction from Vicia faba. First, a single factor analysis examined 3 variables such as extraction temperature, extraction time, and concentration of acetic acid. The purpose of this study was to assess the effects of variables chosen on levodopa's extraction performance. By using variance and regression analyses, a second-order regression equation was determined as a predicted model. The value of R2 is 0.9882, which shows that the equation fits well. The best conditions are as follows: a temperature of 59.85 °C, an extraction time of 18.74 min, and an acetic acid content of 0.28%. Under optimum conditions, the maximum levodopa yield calculated from the predicted module was 4.53%. Extraction efficiency was determined as 4.54% experimentally under optimum conditions. A good relationship has been found between the experimental result and the predicted value.

Mucuna pruriens Administration Minimizes Neuroinflammation and Shows Anxiolytic, Antidepressant and Slimming Effects in Obese Rats

This study evaluated the effect of Mucuna pruriens (MP) administration on neuroinflammation and behavioral and murinometric parameters in obese rats. Proximate composition, oligosaccharide and phenolic compound profile of MP were determined. Wistar adult male rats were randomized into healthy (HG) and obese group (OG). The HG consumed a control chow diet while OG consumed a cafeteria diet for eight weeks. Then, they were subdivided into: Healthy (HG); Healthy with MP administration (HGMP); Obese (OG); Obese with MP administration (OGMP), with the consumption of the respective diets remaining for another eight weeks, in addition to gavage with MP extract to supplemented groups (750 mg/kg weight). MP presented a composition rich in proteins and phenolic compounds, especially catechin, in addition to 1-kestose and levodopa. Supplementation reduced food intake, body weight, and thoracic and abdominal circumferences in obese rats. MP showed anxiolytic and antidepressant effects and reduced morphological damage and expression of interleukin 6 in the hippocampus of obese rats. MP treatment showed satietogenic, slimming, anxiolytic and antidepressant effects, besides to minimizing hippocampal neuroinflammation in obese rats. Our results demonstrated the potential anti-obesity of MP which are probably related to the high content of bioactive compounds present in this plant extract.

L-DOPA synthesis in Mucuna pruriens (L.) DC. is regulated by polyphenol oxidase and not CYP 450/tyrosine hydroxylase: An analysis of metabolic pathway using biochemical and molecular markers

Mucuna pruriens L., commonly known as velvetbean or cow-itch, is a self-pollinated tropical legume of the family Fabaceae, known for its medicinal properties. The active principle L-DOPA extracted from the plant is a potent drug used in the treatment of Parkinson's disease. Although, it is hypothesized that a single step reaction can produce L-DOPA, the presence of optional routes makes the pathway more intricate. For instance, the catecholamine biosynthetic pathway, which leads to L-DOPA production, could occur by hydroxylation of tyrosine to L-DOPA either by polyphenol oxidase (PPO) or tyrosine hydroxylase (TH). Furthermore, Cytochrome P450 (CYP) enzymes can also cause hydroxylation of tyrosine, resulting in L-DOPA synthesis. Therefore, the present investigation was focused on validating the step, which catalyzes the synthesis of L-DOPA, at the biochemical and molecular levels. Enzyme inhibitor studies showed significant inhibition of PPO enzyme with corresponding decrease in L-DOPA synthesis while TH and CYP inhibition had no effect on L-DOPA synthesis. Activity staining of non-denaturing PAGE gel for PPO and TH showed activity only to PPO enzyme. Following in-gel assay and tryptic digestion of the excised stained gel portion, peptide recovery and LC-MS/MS analysis were performed. Degenerate primers based on peptide sequence resulted in an 800bp amplicon. The subsequent sub-cloning, RACE analysis and BLAST search resulted in the isolation of full-length PPO coding sequence of 1800 bp. Structure prediction and phylogenetic analysis of the obtained sequence revealed strong similarity to other plant PPO's like Glycine max, Vigna radiata and Vicia faba of the same family.

A tool for deciphering the redox potential ranking of organic compounds: a case study of biomass-extracted quinones for sustainable energy

Carbonyl compounds have emerged as promising organic electrodes for sustainable energy storage. Accelerating the process of performant materials discovery relies on the possibility of developing methodologies to enable scanning of various sets of candidates. The genesis of this educated guess strategy must be privileged to reduce the search space of experiments, accelerate this research area and contribute to sustainable effort. To address this challenge, we built a quantitative structure-activity relationship to unveil the origin of the redox potential magnitude as a function of both structural features and complexation effects. The potential of this prediction model was demonstrated on various ortho-quinones directly derived from naturally occurring catechols. In addition to the modulation provided by substituent changes, the possibility of applying various types of alkaline(-earth)-ion electrochemistry was examined thoroughly. The power of partitioning the total molecular energy into additive atomic group contributions is highlighted, and the construction of this robust strategy provides guidance towards rational selection of the most suitable compound/metal-ion couples. An upshift/downshift of the redox potential by switching from Li to Mg/Na is revealed, while the identification of the relative role played by the various components of the systems as well as electrostatic interactions is clearly identified. These results, particularly the evidence of the different substituent effects on the single/double reduction potentials and as a function of the type of electrochemistry (Li/Na/Mg), have important implications for designing new electroactive compounds with tailored redox properties.

An assessment of potential nutritive and medicinal properties of Mucuna pruriens: a natural food legume

Mucuna pruriens belongs to the Fabaceae family and is ordinarily known as velvet bean, in English cowitch and Hindi Kawaanch. The restorative quality of this bean makes it an excellent component in pharmaceutical and therapeutic applications. Apart from high protein and starch content, these beans contain (l-Dopa) 3, 4-dihydroxy-l-phenylalanine, which exhibits several medicinal properties. However, it is poisonous when ingested by ruminants. The obstruction to the advancement of Mucuna as nutrition or food is the nearness of antinutrients, which are high as opposed to other uncommon vegetables. Also, this legume is considered as a future restorative herb because of its anticholesterolemic, anti-Parkinson, antioxidant, antidiabetic, sexual enhancing, anti-inflammatory, antimicrobial, and antivenom activities. It also exhibits anticancer activities, but very few studies have been done. The seeds of Mucuna pruriens also contain a vast range of phytochemical constituents such as alkaloids, glycosides, saponins, reducing sugars, and tannins, which provide an avenue to explore it for wider applications. This review sheds light on the possible mechanism of action of Mucuna pruriens on some diseases (hypoglycemia, Parkinson's disease, microbial diseases and tumor). and also fills the gap in the studies of Mucuna pruriens. and Further more in vitro and in vivo studies should be done to explore the potential of these seeds against many diseases, its application as a food source, its antinutrient, and harmful properties as well as its nutraceutical perspective.

Knowing Your Beans in Parkinson's Disease: A Critical Assessment of Current Knowledge about Different Beans and Their Compounds in the Treatment of Parkinson's Disease and in Animal Models

This review contains a critical appraisal of current knowledge about the use of beans in both animal models and patients with Parkinson's disease (PD). The potential beneficial effects of beans in PD are increasingly being touted, not only in scientific journals but also by the lay media. While there is a long tradition in Ayurvedic medicine of prescribing extracts from Mucuna pruriens (MP), whose seeds contain 5% L-3,4-dihydroxyphenylalanin (L-DOPA), many other beans also contain L-DOPA (broad beans, common beans, and soybeans) or have other ingredients (coffee and cocoa) that may benefit PD patients. Indeed, bean-derived compounds can elicit neuroprotective effects in animal models of PD, while several studies in human PD patients have shown that motor performance can improve after ingestion of bean extracts. However, there are several arguments countering the view that beans serve as a natural therapy for PD: (i) the results from animal PD models are not necessarily directly applicable to humans; (ii) beans have many bioactive ingredients, some of which can be harmful in large doses; (iii) studies in human PD patients are scarce and only report on the effects of single doses or the administration of bean extract over short periods of time; and (iv) no data on long-term efficacy or side effects of bean therapy are available. Therefore, reservations about the use of beans as a "natural" therapy for PD seem to be justified.

Effectiveness of Diverse Mesoporous Silica Nanoparticles as Potent Vehicles for the Drug L-DOPA

Our study was focused on the synthesis of selective mesoporous silica nanoparticles (MSNs: MCM-41, MCM-48, SBA-15, PHTS, MCF) that are widely studied for drug delivery. The resulting mesoporous surfaces were conveniently prepared making use of verified synthetic procedures. The MSNs thus obtained were characterized by Brunauer-Emmett-Teller (BET) analysis and scanning electron microscopy (SEM). The selected MSNs with various pore diameters and morphologies were examined to evaluate the capability of L-DOPA drug loading and release. L-DOPA is a well-known drug for Parkinson’s disease. The L-DOPA drug loading and release profiles were measured by UV-VIS spectroscopy and SBA-15 was proved to be the most effective amongst all the different types of tested mesoporous silica materials as L-DOPA drug vehicle.

Development of a Sustainable, Simple, and Robust Method for Efficient l-DOPA Extraction

l-3,4-dihydroxyphenylalanine (l-DOPA) is a medically relevant compound in Parkinson's disease therapy. Several extraction methods of l-DOPA from beans, including velvet and faba beans, have been described in the literature. However, these methods require the use of strong acids, long extraction times, or complex downstream processing, which makes the extraction of l-DOPA expensive and energy-demanding, limiting its industrial application. In addition, the stability of l-DOPA during the extraction process is critical, further complicating the extraction of adequate amounts of this amino acid. This work is the first report on a simple, rapid, greener, and robust extraction method of l-DOPA. The developed method consists of a quick homogenization step followed by a double extraction with 0.2% v/v acetic acid for 20 min and was applied to faba bean at a ratio of 1:25 with respect to the extracting solvent. This study also investigated the stability of l-DOPA during extraction and thermal treatment. The proposed method demonstrated to be robust and extraordinarily efficient for numerous cultivars of faba bean, velvet bean, and food products containing faba beans.

Potential of Aqueous Two-Phase Systems for the Separation of Levodopa from Similar Biomolecules

BACKGROUND

Levodopa is a precursor of several neurotransmitters, such as dopamine, and is used in the treatment of the Parkinson's disease. In this work, an alternative strategy was studied to separate levodopa from similar biomolecules using aqueous two-phase systems (ATPS).

RESULTS

Ternary ATPS composed of polyethylene glycol (PEG) 400 or ionic liquids (ILs), citrate buffer (K3C6H5O7/C6H8O7) at pH 7.0 and water, and quaternary ATPS composed of PEG 400, K3C6H5O7/C6H8O7 at pH 7.0, water and the same ILs at 5 wt%, were studied. The respective liquid-liquid phase diagrams were determined at 298 K to appraise the mixture compositions required to form two-phase systems, followed by studies of the partition of levodopa and structurally similar biomolecules (dopamine, L-phenylalanine, and L-tyrosine). Their partition coefficients and extraction efficiencies have been determined, and the selectivity of the ATPS to separate levodopa from the remaining biomolecules evaluated.

CONCLUSION

The results obtained indicated that PEG-based ATPS were the most effective to separate levodopa from L-phenylalanine while the separation from the other biomolecules was better using IL-based ATPS, in particular those based on [P4444]Cl and [N4444]Cl, with extraction efficiencies of levodopa to the salt-rich phase ranging between 62.7 and 74.0%, and of the remaining biomolecules to polymer/IL-rich phase up to 91.5%.

Effects of bovine lactoferrin on l-DOPA absorption and metabolism in mice

Bioactive natural products, habitually ingested with milk or its derivative nutrients, have been studied for their bioavailability. In this study, we investigated the effects of the co-administration of bovine milk-derived lactoferrin (bLF) and bioactive products, with a focus on catechol-O-methyltransferase (COMT), an enzyme in the catechol metabolism. bLF showed inhibitory activity on COMT in vitro, and acidic pretreatment of bLF enhanced its inhibitory activity. Moreover, partially digested products of bLF by pepsin retained inhibitory activity. Based on these results, bLF was co-administered with levodopa (l-DOPA), which is a catechol compound and a precursor of dopamine, and the effect of bLF on l-DOPA absorption and metabolism was investigated in a mouse model. The co-administration of l-DOPA and bLF alone showed no effect on the concentration of l-DOPA in plasma. However, with the additional administration of carbidopa, the concentration of l-DOPA was significantly enhanced. Furthermore, the ratio of l-DOPA/3-O-methyldopa significantly increased. On the other hand, casein, which is a major milk protein, was not effective. In addition, COMT activity in the intestines was lowered with bLF administration. We concluded that the co-administration of bLF and carbidopa enhances the concentration of l-DOPA.

"Dopamine homeostasis" requires balanced polypharmacy: Issue with destructive, powerful dopamine agents to combat America's drug epidemic

The well-researched pro-dopamine regulator KB220 and variants result in increased functional connectivity in both animal and human brains, and prolonged neuroplasticity (brain cell repair) having been observed in rodents. Moreover, in addition to increased functional connectivity, recent studies show that KB220Z increases overall brain connectivity volume, enhances neuronal dopamine firing, and eliminates lucid dreams in humans over a prolonged period. An unprecedented number of clinical studies validating this patented nutrigenomic technology in re-balancing brain chemistry and optimizing dopamine sensitivity and function have been published. On another note, it is sad that unsuspecting consumers could be deceived and endangered by false promises of knock-off marketers with look- and- sound-alike products. Products containing ingredients having potential dangers (i.e., combinations of potent D2 agonists including L-Dopa and L-Theanine) threaten the credibility and reputation of validated, authentic, and ethical products. We encourage clinicians and neuroscientists to continue to embrace the concept of “dopamine homeostasis” and search for safe, effective, validated and authentic means to achieve a lifetime of recovery, instead of reverting to anti-dopaminergic agents doomed to fail in the war against the devastating drug epidemic, or promoting powerful D2 agonists that compromise needed balance.

Analysis of Levodopa Content in Commercial Mucuna pruriens Products Using High-Performance Liquid Chromatography with Fluorescence Detection

OBJECTIVES

Mucuna pruriens (MP) seeds contain levodopa (up to 2% by weight) and have been used in traditional Indian medicine to treat an illness named "Kampavata," now understood to be Parkinson's disease (PD). Studies have shown MP to be beneficial, and even superior, to levodopa alone in treating PD symptoms. Commercial products containing MP are readily available from online and retail sources to patients and physicians. Products often contain extracts of MP seeds, with significantly higher levodopa content than the seeds. However, MP products have limited regulatory controls with respect to quality and content of active ingredient. The aim of this study was to apply a quantitative method to determine levodopa content in readily available MP products that might be used by patients or in research studies.

DESIGN

Levodopa present in six commercial MP products was quantified by solvent extraction followed by reversed-phase high-performance liquid chromatography (HPLC) coupled to fluorescence detection (FD). Certificates of analysis (COA) were obtained, from manufacturers of MP products, to assess the existence and implementation of specifications for levodopa content.

RESULTS

HPLC-FD analysis revealed that the levodopa content of the six commercial MP products varied from 6% to 141% of individual label claims. No product contained levodopa within normal pharmacopeial limits of 90%-110% label claim. The maximum daily dose of levodopa delivered by the products varied from 14.4 to 720 mg/day. COAs were inconsistent in specifications for and verification of levodopa content.

CONCLUSIONS

The commercial products tested varied widely in levodopa content, sometimes deviating widely from the label claim. These deficiencies could impact efficacy and safety of MP products used by PD patients and compromise the results of scientific studies on MP products. The HPLC-FD method described in this study could be utilized by both manufacturers and scientific researchers to verify levodopa content of MP products.

In vitro and in vivo investigation of natural compounds from seed extract of Mucuna pruriens lacking l-DOPA for the treatment of erectile dysfunction

OBJECTIVE

To investigate the biological effects of the Mucuna pruriens (M. pruriens) seed extracts that lacked l-DOPA, which was formerly reported as the active ingredient, on erectile dysfunction (ED) both in vitro and in vivo.

METHODS

Seed of M. pruriens plant that cultivated in Mae Taeng District, Chiang Mai Province, Thailand, was collected. Component of its seeds were extracted and isolated into 2 fractions using methanol, polar and nonpolar. Each fraction was investigated for phytochemicals using gas chromatography and mass spectroscopy and was screened for biological activity in vitro using three different cell lines. The most biological active fraction was used to treat both streptozotocin (STZ)-induced diabetes mellitus-erectile dysfunction (DM-ED) male Wistar rats and normal rats (n = 6 per groups) to compare the effect on sexual behavior parameters, including number of intromission, mounting and ejaculation, with that of rats given Sildenafil by individually pairing with their female counterparts. Penile tissues and serums were collected to determine histological structure, related gene expression and biomolecules.

RESULTS

The phytochemicals of the polar fraction were possibly catechol and its derivatives plus polyphenols, whereas the nonpolar fraction consisted of lipid derivatives. l-DOPA was not detected in either of the extracts. The polar fraction was able to up-regulate the expression of ED-related genes including eNOS and nNOS in vitro which subsequently promotes nitric oxide production and maintains intracellular cyclic guanosine monophosphate levels. When administrated to DM-ED rats, the polar extract significantly improved all sexual behavior parameters in DM-ED rats compared to untreated group (18.3 ± 1.8 to 10.8 ± 2.9 for intromission, 9.8 ± 2.2 to 5.7 ± 1.3 for mounting, and 1.8 ± 0.6 to 0.2 ± 0.4 for ejaculation). That effect might due to the ability of the extract to stimulate the expression of eNOS and nNOS which results in nitric oxide production and subsequently maintains cyclic guanosine monophosphate levels in penile tissue. Moreover, this extract may also prevent penile tissue deterioration due to diabetes.

CONCLUSIONS

The polar extract of M. pruriens seed can be used for ED therapy, especially in patients with metabolic diseases including diabetes. The action of the extract might be due to catechol and its derivatives and polyphenols.

Inducing mutations through γ-irradiation in seeds of Mucuna pruriens for developing high L-DOPA-yielding genotypes

PURPOSE

To develop elite genotypes in Mucuna pruriens (L.) DC with high L-DOPA (L-3, 4 dihydroxyphenylalanine) yields, with non-itching characteristics and better adaptability by applying γ-irradiation. Molecular and chemical analysis was performed for screening based on specific characteristics desired for developing suitable genotypes.

MATERIALS AND METHODS

Developed, mutant populations were analyzed for L-DOPA % in seeds through TLC (thin layer chromatography), and the results obtained were validated with the HPLC (High performance liquid chromatography). The DNA (Deoxyribonucleic acid) was isolated from the leaf at the initial stage and used for DNA polymorphism. RNA (Ribonucleic acid) was isolated from the leaf during maturity and used for expression analysis.

RESULTS

The selected mutant T-I-7 showed 5.7% L-DOPA content compared to 3.18% of parent CIM-Ajar. The total polymorphism obtained was 57% with the molecular marker analysis. The gene expression analysis showed higher fold change expression of the dopadecarboxylase gene (DDC) in control compared to selected mutants (T-I-7, T-II-23, T-IV-9, T-VI-1).

CONCLUSION

DNA polymorphism was used for the screening of mutants for efficient screening at an early stage. TLC was found suitable for the large-scale comparative chemical analysis of L-DOPA. The expression profile of DDC clearly demonstrated the higher yields of L-DOPA in selected mutants developed by γ-irradiation in the seeds of the control.