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Journal of Food Science Jun 2023Phytol is a diterpene alcohol found abundantly in nature as the phytyl side chain of chlorophylls. Free form of phytol and its metabolites have been attracting attention...
Phytol is a diterpene alcohol found abundantly in nature as the phytyl side chain of chlorophylls. Free form of phytol and its metabolites have been attracting attention because they have a potential to improve the lipid and glucose metabolism. On the other hand, phytol is unfavorable for those who suffering from Refsum's disease. However, there is little information on the phytol contents in leafy vegetables rich in chlorophylls. This study indicated that raw spinach leaves contain phytol of 0.4-1.5 mg/100 g fresh weight. Furthermore, crude enzyme extracted from the leaves showed the enzyme activities involved in dephytylation of chlorophyll derivatives and they were high at mild alkaline pH and around 45°C, and lowered at 55°C or above. Under the optimum pH and temperature for such enzymes determined in the model reaction using the crude enzyme, phytol content in the smoothie made from raw spinach leaves increased with an increase of chlorophyllide, another reaction product. Comparison between the increased amounts of phytol and chlorophyllide showed that the enzymatic dephytylation of chlorophylls was critically responsible for the increase of phytol in the smoothie. PRACTICAL APPLICATION: Phytol, which is released by the enzymes related to chlorophyll metabolism in plants, has been investigated because of its potential abilities to improve the lipid metabolism and blood glucose level. In contrast to such health benefits, they are known to be toxic for patients suffering from Refsum's disease. This research for the first time reports the phytol content in raw spinach leaves and that phytol can be increased in the smoothie made from spinach leaves by the action of endogenous enzymes on chlorophyll derivatives under a certain condition. These results help control phytol content in the smoothies.
Topics: Humans; Chlorophyllides; Spinacia oleracea; Refsum Disease; Phytol; Chlorophyll
PubMed: 37122139
DOI: 10.1111/1750-3841.16588 -
The Plant Journal : For Cell and... Mar 2022During chlorophyll degradation, large amounts of the isoprenoid alcohol phytol are released. The pathway of phytol catabolism has been studied in humans, because...
During chlorophyll degradation, large amounts of the isoprenoid alcohol phytol are released. The pathway of phytol catabolism has been studied in humans, because chlorophyll is part of the human diet, but little is known for plants. In humans, phytanoyl-CoA derived from phytol is degraded via α-oxidation by phytanoyl-CoA hydroxylase (PAHX) and 2-hydroxy-phytanoyl-CoA lyase (HPCL). Arabidopsis contains two sequences homologous to the human proteins AtPAHX and AtHPCL. Insertional mutants of Arabidopsis (pahx, hpcl) were grown under N deprivation to stimulate chlorophyll breakdown or supplemented with phytol to increase the endogenous amount of phytol. During N deprivation, chlorophyll, phytol, phytenal, upstream metabolites of phytol breakdown, and tocopherol and fatty acid phytyl esters, alternative phytol-derived lipids, accumulated in pahx and hpcl mutants, in line with the scenario that the mutations interfere with phytol degradation. AtHPCL was localized to the peroxisomes. Expression analysis of the AtHPCL sequence in the yeast Δpxp1 or Δmpo1 mutants followed by supplementation with 2-hydroxy-palmitic acid and enzyme assays of peroxisomal proteins from Col-0 and hpcl plants with 2-hydroxy-stearoyl-CoA revealed that AtHPCL harbors 2-hydroxy-acyl-CoA lyase activity. The α-dioxygenases αDOX1 and αDOX2 are involved in α-oxidation of fatty acids and could be involved in an alternative pathway of phytol degradation. However, phytol-related lipids in the αdox1, αdox2, or αdox1 αdox2 mutants were not altered compared with Col-0, indicating that αDOX1 and αDOX2 are not involved in phytol degradation. These results demonstrate that phytol degradation in Arabidopsis involves α-oxidation by AtPAHX and AtHPCL, but that it is independent of αDOX1/αDOX2.
Topics: Arabidopsis; Chlorophyll; Coenzyme A; Fatty Acids; Lyases; Phytanic Acid; Phytol
PubMed: 34902195
DOI: 10.1111/tpj.15632 -
World Journal of Microbiology &... Nov 2023Vitamin K (menaquinone, VK, MK) is an essential lipid-soluble vitamin that plays critical roles in inhibiting cell ferroptosis, improving blood clotting, and preventing... (Review)
Review
Vitamin K (menaquinone, VK, MK) is an essential lipid-soluble vitamin that plays critical roles in inhibiting cell ferroptosis, improving blood clotting, and preventing osteoporosis. The increased global demand for VK has inspired interest in novel production strategies. In this review, various novel metabolic regulation strategies, including static and dynamic metabolic regulation, are summarized and discussed. Furthermore, the advantages and disadvantages of both strategies are analyzed in-depth to highlight the bottlenecks facing microbial VK production on an industrial scale. Finally, advanced metabolic engineering biotechnology for future microbial VK production will also be discussed. In summary, this review provides in-depth information and offers an outlook on metabolic engineering strategies for VK production.
Topics: Vitamin K 2; Metabolic Engineering; Biotechnology
PubMed: 37938463
DOI: 10.1007/s11274-023-03828-5 -
American Journal of Transplantation :... Apr 2023Vitamin K deficiency is common among kidney transplant recipients (KTRs) and likely contributes to progressive vascular calcification and stiffness. In this... (Randomized Controlled Trial)
Randomized Controlled Trial
Effect of vitamin K supplementation on serum calcification propensity and arterial stiffness in vitamin K-deficient kidney transplant recipients: A double-blind, randomized, placebo-controlled clinical trial.
Vitamin K deficiency is common among kidney transplant recipients (KTRs) and likely contributes to progressive vascular calcification and stiffness. In this single-center, randomized, double-blind, placebo-controlled trial, we aimed to investigate the effects of vitamin K supplementation on the primary end point, serum calcification propensity (calciprotein particle maturation time, T50), and secondary end points arterial stiffness (pulse wave velocity [PWV]) and vitamin K status in 40 vitamin K-deficient KTRs (plasma dephosphorylated uncarboxylated matrix Gla protein [dp-ucMGP] ≥500 pmol/L). Participants (35% female; age, 57 ± 13 years) were randomized 1:1 to vitamin K2 (menaquinone-7, 360 μg/day) or placebo for 12 weeks. Vitamin K supplementation had no effect on calcification propensity (change in T50 vs baseline +2.3 ± 27.4 minutes) compared with placebo (+0.8 ± 34.4 minutes; P = .88) but prevented progression of PWV (change vs baseline -0.06 ± 0.26 m/s) compared with placebo (+0.27 ± 0.43 m/s; P = .010). Vitamin K supplementation strongly improved vitamin K status (change in dp-ucMGP vs baseline -385 [-631 to -269] pmol/L) compared with placebo (+39 [-188 to +183] pmol/L; P < .001), although most patients remained vitamin K-deficient. In conclusion, vitamin K supplementation did not alter serum calcification propensity but prevented progression of arterial stiffness, suggesting that vitamin K has vascular effects independent of calciprotein particles. These results set the stage for longer-term intervention studies with vitamin K supplementation in KTRs. TRIAL REGISTRY: EU Clinical Trials Register (EudraCT Number: 2019-004906-88) and the Dutch Trial Register (NTR number: NL7687).
Topics: Humans; Female; Adult; Middle Aged; Aged; Male; Vitamin K; Vascular Stiffness; Kidney Transplantation; Pulse Wave Analysis; Vitamin K 2; Dietary Supplements; Double-Blind Method
PubMed: 36695702
DOI: 10.1016/j.ajt.2022.12.015 -
Atencion Primaria Oct 2022Two important topics about children and adolescents in our primary care activity are presented in this update document: tobacco smoking prevention in adolescence and...
Two important topics about children and adolescents in our primary care activity are presented in this update document: tobacco smoking prevention in adolescence and prophylaxis with vitamin K to prevent the hemorrhagic disease of the newborn.
Topics: Infant, Newborn; Humans; Adolescent; Child; Smoking Prevention; Vitamin K
PubMed: 36435589
DOI: 10.1016/j.aprim.2022.102441 -
International Journal For Vitamin and... Apr 2024Vitamin K (VK) is a fat-soluble vitamin that is indispensable for the activation of vitamin K-dependent proteins (VKDPs). It has been shown to play an important role in... (Review)
Review
Vitamin K (VK) is a fat-soluble vitamin that is indispensable for the activation of vitamin K-dependent proteins (VKDPs). It has been shown to play an important role in the proper calcium deposit at the bone level, hindering that on the vascular walls. The deficiency of this vitamin in European populations is frequent and unknown. It is related to several factors, poor dietary intake, altered intestinal absorption or altered production by bacteria, indicating possible dysbiosis. For Vitamin K2 (VK2), there is currently no official reference daily intake (RDI). However, the effects of VK2 on the improvement of health in cardiovascular diseases, on bone metabolism, on chronic kidney diseases have been the subject of research in recent decades. The microbiota in the gastrointestinal tract plays an important role: are primarily capable of synthetizing very long chain forms of menaquinones and, in addition to the bacteria present in the intestinal flora, VK2 is also produced by bacteria used in food fermentation processes. This review provides an update on the current literature regarding the origin of VK2 and its implications in what is called the "calcium paradox", namely the lack of calcium in the bone and its storage in the wall of the vessel.
Topics: Vitamin K 2; Calcium; Vitamin K; Vitamins
PubMed: 36039403
DOI: 10.1024/0300-9831/a000761 -
BMJ Open May 2023Vitamin K has been suggested to have protective effects against progression of vascular calcification and development of cardiovascular disease (CVD). However, few...
Study protocol of the InterVitaminK trial: a Danish population-based randomised double-blinded placebo-controlled trial of the effects of vitamin K (menaquinone-7) supplementation on cardiovascular, metabolic and bone health.
INTRODUCTION
Vitamin K has been suggested to have protective effects against progression of vascular calcification and development of cardiovascular disease (CVD). However, few well-powered randomised controlled trials have examined whether vitamin K prevents progression of vascular calcification in individuals from the general population. The aim of the InterVitaminK trial is to investigate the effects of vitamin K supplementation (menaquinone-7, MK-7) on cardiovascular, metabolic, respiratory and bone health in a general ageing population with detectable vascular calcification.
METHODS AND ANALYSIS
The InterVitaminK trial is a randomised, double-blinded, placebo-controlled, trial. A total of 450 men and women aged 52-82 years with detectable coronary artery calcification (CAC), but without manifest CVD, will be randomised (1:1) to receive daily MK-7 (333 µg/day) or placebo tablets for 3 years. Health examinations are scheduled at baseline, and after 1, 2 and 3 years of intervention. Health examinations include cardiac CT scans, measurements of arterial stiffness, blood pressure, lung function, physical function, muscle strength, anthropometric measures, questionnaires on general health and dietary intake, and blood and urine sampling. The primary outcome is progression of CAC from baseline to 3-year follow-up. The trial has 89% power to detect a between-group difference of at least 15%. Secondary outcomes are bone mineral density, pulmonary function and biomarkers of insulin resistance.
ETHICS AND DISSEMINATION
Oral MK-7 supplementation is considered safe and has not been found to cause severe adverse events. The Ethical Committee of the Capital Region (H-21033114) approved the protocol. Written informed consent is obtained from all participants and the trial is conducted in accordance with the Declaration of Helsinki II. Both negative and positive findings will be reported.
TRIAL REGISTRATION NUMBER
NCT05259046.
Topics: Male; Humans; Female; Vitamin K; Bone Density; Vitamin K 2; Lung; Coronary Artery Disease; Vascular Calcification; Dietary Supplements; Denmark; Double-Blind Method; Randomized Controlled Trials as Topic
PubMed: 37208133
DOI: 10.1136/bmjopen-2023-071885 -
Inhalation Toxicology Jan 2021The use of vaping pens for inhalation of cannabinoid derived products is rising and has become a popular alternative to smoking combustible products. For efficient...
The use of vaping pens for inhalation of cannabinoid derived products is rising and has become a popular alternative to smoking combustible products. For efficient product delivery, additives are sometimes added and vaping pens often may include compounds like Phytol or Propylene Glycol as thinning agents. This study aimed at comparing Phytol and Propylene Glycol with respect to potential toxicity and safe use in vaping products. Male and female Sprague Dawley rats were exposed to 5 mg/L of Phytol or Propylene Glycol for up to 6 hours over up to 14 days and monitored for clinical signs and changes in body weight. Gross necropsy and histopathology of respiratory tissue was performed to assess potential adverse effects. Phytol exposed animals expressed severe clinical signs, body weight loss and mortality after one or two exposure days, leading to termination of all dose groups for this compound. Lung weights were increased and respiratory tissue was severely affected, demonstrating dose-responsive tissue degeneration, necrosis, edema, hemorrhage and inflammation. Propylene Glycol exposed animals did not show any adverse reactions after 14 days of high dose exposure. For Phytol, a low observed adverse effect level (LOAEL) was determined at ≤109.0/10.9 mg/kg/day presented/deposited dose and therefore its use as excipient in vaping product is not recommend; a safe exposure range was not established for Phytol. Propylene Glycol, in contrast, is considered safe with a no observed adverse effect level (NOAEL) at 1151.7/115.2 mg/kg/day presented/deposited dose in rats.
Topics: Animals; Female; Inhalation Exposure; Lung Injury; Male; Phytol; Propylene Glycol; Rats; Rats, Sprague-Dawley
PubMed: 33441006
DOI: 10.1080/08958378.2020.1867260 -
Journal of Nutritional Science and... 2022Vitamins are a family of micronutrients comprising 13 groups of organic compounds, of which vitamin B1 was identified first, approximately 110 y ago. Deficiency of each... (Review)
Review
Vitamins are a family of micronutrients comprising 13 groups of organic compounds, of which vitamin B1 was identified first, approximately 110 y ago. Deficiency of each vitamin results in specific symptoms, such as neuropathy, dermatitis, diarrhea, dementia, pernicious anemia, scurvy, blindness, rickets, and bleeding. Almost all vitamins can modulate the functions of enzymes and/or other proteins involved in the formation of bone and soft tissues, generation of energy, and regulation of homeostasis via specific vitamin-protein interactions. In addition to the well-known physiological roles of vitamins, novel modes of action of vitamins have been elucidated. These new functions could contribute to extending healthy life expectancy by preventing and curing lifestyle-related diseases. In this mini-review, we introduce the functional properties of three vitamins, vitamin B3 (niacin), biotin, and vitamin K, for the prevention of age-related diseases.
Topics: Vitamins; Vitamin A; Vitamin K; Thiamine; Life Style
PubMed: 36437027
DOI: 10.3177/jnsv.68.S8 -
Food Chemistry Mar 2017Extracts with water:ethanol (100:0, 70:30, 50:50, 30:70, 0:100) solutions from fresh (F), just dried (JD), dried and stored for one year (DS) Justicia spicigera leaves...
Extracts with water:ethanol (100:0, 70:30, 50:50, 30:70, 0:100) solutions from fresh (F), just dried (JD), dried and stored for one year (DS) Justicia spicigera leaves were obtained using the stirring and ultrasound techniques. Extracts were analyzed in physicochemical and antioxidant characteristics. Identification of chemical compounds by gas chromatography-mass spectroscopy (GC-MS) was also performed. 2.14±0.91, 5.67±1.70, and 8.52±4.97g Gallic acid equivalents/100g dry weight (d.w.) of phenolic compounds were found, in average, for F, JD, and DS J. spicigera, respectively. 2.22±1.31, 2.58±2.11, and 8.48±3.78g Trolox equivalents/100g d.w. were detected with the ABTS method and 0.49±0.33, 1.23±0.87, and 0.88±0.94g with the DPPH method for F, JD and DS J. spicigera, respectively. Eucalyptol, phytol, and azulene were identified as the main compounds. J. spicigera showed colors (green-iridescent, green-yellow, or pink of different intensities) and antioxidant characteristics depending on the solvent concentration. Extracts could be used in the food and pharmaceutical industries.
Topics: Antioxidants; Azulenes; Chemical Phenomena; Chromans; Color; Cyclohexanols; Eucalyptol; Gallic Acid; Gas Chromatography-Mass Spectrometry; Justicia; Monoterpenes; Phenols; Phytol; Plant Extracts; Plant Leaves
PubMed: 27719914
DOI: 10.1016/j.foodchem.2016.09.078