Effects of ascorbic acid on axillary shoot induction in Tylophora indica (Burm. f.) Merrill.

1992 ◽  
Vol 29 (2) ◽  
pp. 109-113 ◽  
Author(s):  
Neelam Sharma ◽  
K. P. S. Chandel
Keyword(s):  
Ascorbic Acid ◽  
Axillary Shoot ◽  
Shoot Induction ◽  
Tylophora Indica

scholarly journals Shoot Induction from Axillary Shoot Tip Explants of Fig (Ficus carica) cv. Japanese BTM 6

2018 ◽  
Vol 29 (2) ◽  
pp. 165-174 ◽  
Author(s):  
Wan Ting Ling ◽  
◽  
Fui Chu Liew ◽  
Wei Yong Lim ◽  
Sreeramanan Subramaniam ◽  
...  
Keyword(s):  
Shoot Tip ◽  
Ficus Carica ◽  
Axillary Shoot ◽  
Shoot Induction ◽  
Shoot Tip Explants

scholarly journals Histochemical and Shoot Induction Studies of Basella rubra L. (Basellaceae)

2019 ◽  
Vol 16 (1) ◽  
pp. 187-194
Author(s):  
M.N. Abubacker ◽  
G. Ganapathy ◽  
L. Maria Sebastin ◽  
K. Suresh Mondal
Keyword(s):  
Ascorbic Acid ◽  
In Vitro Regeneration ◽  
Ms Medium ◽  
Shoot Induction ◽  
Ex Vitro ◽  
Sodium Magnesium ◽  
Tannin Concentration ◽  
Subsequent Effect

The optimum concentrations of the plant hormones for in vitro regeneration and subsequent effect of auxins on rooting (in vitro and ex vitro) of shoots of Basella rubra L. have been investigated in present study. Nodal shoot segments were used as explants to initiate the cultures. Histochemical studies of in vitro and in vivo plants revealed alkaloids, polyphenols and terpenoids concentrations were higher in in vivo plants. Ascorbic acid and tannin concentration have shown no difference in the content in in vitro and in vivo plants. MS medium supplemented with IBA 2.0 mg/l + NAA 0.5 mg/l + GA3 0.5 mg/l induced shoot regeneration MS+IBA 3.0 mg/l induced roots and the plant regeneration was achieved in MS + IBA 0.5 mg/l + GA3 1.5 mg/l + IAA 1.0 mg/l. SEM – EDX elemental analysis of in vitro plants have shown absorption of sodium, magnesium, silica, phosphorus, sulphur, chlorine and potassium from the medium. The in vivo plants have shown absorption of magnesium, silica, chlorine, potassium, calcium and iron.

scholarly journals Micropropagation of Helleborus orientalis Lam. and Aconitum uncinatum Linn. (Ranunulaceae)

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 871D-871 ◽  
Author(s):  
C.C. Lim ◽  
S.L. Kitto
Keyword(s):  
Ascorbic Acid ◽  
Basal Medium ◽  
Shoot Proliferation ◽  
Axillary Shoot ◽  
Field Plot ◽  
Axillary Shoots ◽  
Axillary Shoot Proliferation ◽  
Active Radiation ◽  
Helleborus Orientalis

The objectives of this study were to develop systems for mass proliferation, rooting, and reestablishment of microcuttings of Helleborus orientalis and Aconitum uncinatum. Basal medium for H. orientalis contained 1/2 MS with 0.4 mg thiamine–HCl/liter, 0.5 mg pyridoxine–HCI/liter, 0.5 mg nicotinic acid/liter, 100 mg i-inositol/liter, 5 mg BA/liter, 2% sucrose, and 0.7% Phytagar. There was no effect of GA (1 mg–liter–1) or TDZ (0.1, 1 mg–liter–1) on axillary shoot proliferation. Helleborus orientalis rooted in vermiculite, Redi-Earth, or 4 perlite: 1 peat with 50% to 56% survival. A field plot containing 18 clonal H. orientalis has been established. Basal medium for A. uncinatum contained WPM with 2% sucrose, 2.5 mg BA/liter, 150 ppm ascorbic acid, 150 ppm citric acid, and 0.7% Phytagar. There was no effect of photoperiod (8, 12, 14 h, 52.5 μmol–m–2–s–1 photosynthetic active radiation) or banana extract on axillary shoot proliferation. Significantly more axillary shoots were generated in the presence of BA (10 mg–liter–1) + kinetin (10 mg–liter–1). Medium containing 500 ppm of PVPP resolved blackening of microcutting bases. More than 500 in vitro-rooted microcuttings (1 mg IBA/liter) survived and grew when transplanted into MetroMix 510 and placed under humidity domes for 6 weeks in the mist.

Comparative Study of Ascorbic Acid Levels in Gastric Secretion, Blood, Urine and Saliva

1951 ◽  
Vol 18 (2) ◽  
pp. 224-229 ◽  
Author(s):  
Joseph T. Freeman ◽  
Roberta Hafkesbring
Keyword(s):  
Ascorbic Acid ◽  
Gastric Secretion ◽  
Comparative Study

Sorbitol enhances the physicochemical stability of B12 vitamers

2020 ◽  
Vol 90 (5-6) ◽  
pp. 439-447 ◽  
Author(s):  
Andrew Hadinata Lie ◽  
Maria V Chandra-Hioe ◽  
Jayashree Arcot
Keyword(s):  
Ascorbic Acid ◽  
Uv Light ◽  
Heat Exposure ◽  
Water Soluble ◽  
Uv Exposure ◽  
Physicochemical Stability ◽  
Before And After ◽  
The Stability

Abstract. The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%–26% and 48%–76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.

Inhibition of Pro-Inflammatory Cytokine Secretion by Select Antioxidants in Human Coronary Artery Endothelial Cells

2020 ◽  
Vol 90 (1-2) ◽  
pp. 103-112 ◽  
Author(s):  
Michael J. Haas ◽  
Marilu Jurado-Flores ◽  
Ramadan Hammoud ◽  
Victoria Feng ◽  
Krista Gonzales ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Ascorbic Acid ◽  
Coronary Artery ◽  
Inflammatory Cytokines ◽  
Inflammatory Cytokine ◽  
Culture Media ◽  
Cytokine Secretion ◽  
Human Coronary Artery ◽  
Tnf Α ◽  
Pro Inflammatory Cytokines

Abstract. Inflammatory and oxidative stress in endothelial cells are implicated in the pathogenesis of premature atherosclerosis in diabetes. To determine whether high-dextrose concentrations induce the expression of pro-inflammatory cytokines, human coronary artery endothelial cells (HCAEC) were exposed to either 5.5 or 27.5 mM dextrose for 24-hours and interleukin-1β (IL-1β), interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor α (TNF α) levels were measured by enzyme immunoassays. To determine the effect of antioxidants on inflammatory cytokine secretion, cells were also treated with α-tocopherol, ascorbic acid, and the glutathione peroxidase mimetic ebselen. Only the concentration of IL-1β in culture media from cells exposed to 27.5 mM dextrose increased relative to cells maintained in 5.5 mM dextrose. Treatment with α-tocopherol (10, 100, and 1,000 μM) and ascorbic acid (15, 150, and 1,500 μM) at the same time that the dextrose was added reduced IL-1β, IL-6, and IL-8 levels in culture media from cells maintained at 5.5 mM dextrose but had no effect on IL-1β, IL-6, and IL-8 levels in cells exposed to 27.5 mM dextrose. However, ebselen treatment reduced IL-1β, IL-6, and IL-8 levels in cells maintained in either 5.5 or 27.5 mM dextrose. IL-2 and TNF α concentrations in culture media were below the limit of detection under all experimental conditions studied suggesting that these cells may not synthesize detectable quantities of these cytokines. These results suggest that dextrose at certain concentrations may increase IL-1β levels and that antioxidants have differential effects on suppressing the secretion of pro-inflammatory cytokines in HCAEC.

Ascorbic Acid does not Improve Endothelium-Dependent Flow-mediated Dilatation of the Brachial Artery in Patients with Raynaud’s Phenomenon Secondary to Systemic Sclerosis

2003 ◽  
Vol 73 (1) ◽  
pp. 3-7 ◽  
Author(s):  
M. E. Mavrikakis ◽  
J. P. Lekakis ◽  
M. Papamichael ◽  
K. S. Stamatelopoulos ◽  
Ch. C. Kostopoulos ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Smooth Muscle ◽  
Systemic Sclerosis ◽  
Endothelial Dysfunction ◽  
Brachial Artery ◽  
Raynaud’S Phenomenon ◽  
Raynaud's Phenomenon ◽  
Water Soluble ◽  
Placebo Administration ◽  
Flow Mediated Dilatation

Previous studies have shown that patients with Raynaud’s phenomenon secondary to systemic sclerosis present abnormal endothelial function; the mechanisms responsible for the endothelial dysfunction are unknown but increased vascular oxidative stress could be a possible cause. The hypothesis that a potent water-soluble antioxidant can reverse endothelial dysfunction in these patients was tested in the present study. We examined 11 female patients with Raynaud’s phenomenon secondary to systemic sclerosis and ten healthy control women by ultrasound imaging of the brachial artery to assess flow-mediated (endothelium-dependent) and nitrate-induced (endothelium-independent) vasodilatation. Flow-mediated dilatation and nitrate-induced dilatation were significantly reduced in patients with Raynaud’s phenomenon, indicating abnormal endothelial and smooth muscle cell function. Patients with Raynaud’s phenomenon entered a double-blind, randomized, crossover placebo-controlled trial and received orally 2 g of ascorbic acid or placebo; vascular studies were repeated two hours after ascorbic acid or placebo administration. Flow-mediated dilatation did not improve after ascorbic acid (1.6 ± 2.2% to 2.2 ± 2.5%, ns) or placebo administration (1.2 ± 1,9% to 1.7 ± 1.4%, ns); also nitrate-induced dilatation was similar after ascorbic acid or placebo (16 ± 7.4% vs 17 ± 8%, ns), suggesting no effect of ascorbic acid on endothelial and vascular smooth muscle function. In conclusion, ascorbic acid does not reverse endothelial vasomotor dysfunction in the brachial circulation of patients with Raynaud’s phenomenon secondary to systemic sclerosis. The use of different antioxidants or different dosing of ascorbic acid may be required to show a beneficial effect on endothelial vasodilator function.

Sign in / Sign up

Export Citation Format

Share Document