The radial distribution and metabolism of IAA-14C in Pinus echinata stems in relation to wood formation

1974 ◽  
Vol 52 (6) ◽  
pp. 1349-1355 ◽  
Author(s):  
Lawrence E. Nix ◽  
Tomasz J. Wodzicki
Keyword(s):  
Radial Distribution ◽  
Indoleacetic Acid ◽  
Methanol Extract ◽  
Growing Season ◽  
Wood Formation ◽  
Pinus Echinata ◽  
Aqueous Fraction ◽  
Seasonal Transition ◽  
Methanolic Extracts ◽  
Solvent Systems

Radial distribution of auxin in differentiating xylem tissues was studied in decapitated 8- to 14-year-old Pinus echinata stems to which indoleacetic acid (IAA-14C) in lanolin paste was applied during early and late growing season. Small segments of the treated stems were sectioned tangentially with a sliding microtome, the serial sections were collected, and the radioactivity of each section was measured. The results indicate that IAA is radially distributed in the differentiating tissues along a steep gradient from the cambial region to the differentiating xylem and that this distribution varies during the growing season in relation to the seasonal transition to latewood formation in intact trees.Forty-five to 60% of the radioactivity recovered in methanolic extracts of the differentiating xylem after a 2-day labeling period was in the form of IAA. After 7 days 10–15% of the radioactivity recovered was in the form of IAA. The radioactivity recovered separated into ether and aqueous fractions when the methanol extract was reduced, acidified, and partitioned with ether. Chromatography of aliquots of both fractions in several solvent systems revealed no individually significant metabolite of IAA. The aqueous fraction derivatives accumulated in the tissue, and later in the season the metabolism of IAA and the accumulation of the aqueous fraction apparently decreased. In experiments where excised differentiating xylem was incubated with a liquid medium containing IAA-14C, the conversion of radioactivity to the aqueous fraction was twofold greater in early season than in late season. The significance of the results is discussed with possible relation to the control of the seasonal transition to latewood formation in conifers.

scholarly journals Different climate sensitivity for radial growth, but uniform for tree-ring stable isotopes along an aridity gradient in Polylepis tarapacana, the world’s highest elevation tree-species

2021 ◽  
Author(s):  
Milagros Rodriguez-Caton ◽  
Laia Andreu-Hayles ◽  
Mariano S Morales ◽  
Valérie Daux ◽  
Duncan A Christie ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Carbon Source ◽  
Tree Ring ◽  
Tree Growth ◽  
Carbon Sink ◽  
Growing Season ◽  
Wood Formation ◽  
Aridity Gradient ◽  
Leaf Level ◽  
Δ13c And Δ18o

Abstract Tree growth is generally considered to be temperature-limited at upper elevation treelines. Yet, climate factors controlling tree growth at semiarid treelines are poorly understood. We explored the influence of climate on stem growth and stable isotopes for Polyepis tarapacana, the world’s highest elevation tree-species found only in the South American Altiplano. We developed tree-ring width index (RWI), oxygen (δ18O) and carbon (δ13C) chronologies for the last 60 years at four P. tarapacana stands located above 4,400 meters in elevation, along a 500-km latitude-aridity gradient. Total annual precipitation decreased from 300 to 200 mm from the northern to the southern sites. We used RWI as a proxy of wood formation (carbon sink) and isotopic tree-ring signatures as proxies of leaf-level gas exchange processes (carbon source). We found distinct climatic conditions regulating carbon-sink processes along the gradient. Current-growing season temperature regulated RWI at wetter-northern sites, while prior-growing season precipitation determined RWI at arid-southern sites. This suggests that the relative importance of temperature to precipitation in regulating tree growth is driven by site-water availability. In contrast, warm and dry growing-seasons resulted in enriched tree-ring δ13C and δ18O at all study sites, suggesting that similar climate conditions control carbon-source processes. Site-level δ13C and δ18O chronologies were significantly and positively related at all sites, with the strongest relationships among the southern-drier stands. This indicates an overall regulation of intercellular carbon dioxide via stomatal conductance for the entire P. tarapacana network, with greater stomatal control when aridity increases. The manuscript also highlights a coupling and decoupling of physiological processes at leaf level versus wood formation depending on their respectively uniform and distinct sensitivity to climate. This study contributes to better understand and predict the response of high-elevation Polylepis woodlands to rapid climate changes and projected drying in the Altiplano.

Isolation of the antidiarrhoeal tiliroside and its derivative from Waltheria indica leaf extract

2021 ◽  
Vol 25 (1) ◽  
pp. 86-92
Author(s):  
B.A. Ayinde ◽  
J.O. Owolabi ◽  
I.S. Uti ◽  
P.C. Ogbeta ◽  
M.I. Choudhary
Keyword(s):  
Silica Gel ◽  
Column Chromatography ◽  
Methanol Extract ◽  
Preparative Thin Layer Chromatography ◽  
Inhibitory Effects ◽  
Aqueous Fraction ◽  
Vacuum Liquid Chromatography ◽  
Ileum Contraction ◽  
Layer Chromatography ◽  
Dose Dependent

The antidiarrhoeal effect of Waltheria indica methanol extract and fractions have been reported earlier but, the present work examined the intestinal relaxant effects of two flavonoid-phenyl propanoids isolated from the methanol extract. The active aqueous fraction was subjected to vacuum liquid chromatography using dichloromethane with increasing concentration of ethyl acetate, and that of methanol and water successively. The ten (10) fractions obtained were combined to give seven (7). The fraction 2 (C, D) was subjected to preparative thin layer chromatography on silica gel GF254 (10-40μm) using CHCl3-CH3OH (8:2) to obtain compound coded F2. Fraction 4 (F) was subjected to column chromatography using silica gel (60-120μm mesh) and eluted with  dichloromethane with increasing concentrations of methanol. Fractions 9-28 were combined and subjected to column  chromatography using chloroform with increasing concentration of methanol. The fractions 1-16 of these were purified on Sephadex LH-20 to obtain compound BAA. The identities of the two compounds were established using spectroscopic methods. The  antidiarrheal effect of compound F2 was evaluated on mice using charcoal transit (100,200, 400mg/kg), castor oil (40, 60 mg/kg)  while the two compounds were examined for their inhibitory effects on Ach-induced ileum contraction. The effects of the  compounds were compared with loperamide (3mg/kg) and atropine (80μg). Compounds F2 and BAA were identified as tiliroside and 3’’’, 5’’’-dimethoxy tiliroside respectively. Tiliroside inhibited the charcoal transition in the animals in a dose dependent pattern with 400mg/ mL eliciting 63.41% inhibition compared to 59.23% produced by loperamide. The compound also elicited significantly (P<0.05) prolonged onset of stooling and reduced the number and weight of stools produced lower than the control. The two  compounds drastically inhibited the Ach-induced contractions of the ileum. The compound, tiliroside at 10mg, completely abolished  the contraction by Ach unlike 3’’’, 5’’’-dimethoxy tiliroside which reduced the contraction to 1.92% at 20mg. The identified compounds seem to be responsible for the ethnomedicinal use of the plant in treating diarrhea.

scholarly journals Phytochemical and Biological Investigations of Eurya acuminata (Theaceae)

2017 ◽  
Vol 15 (2) ◽  
pp. 151-154 ◽  
Author(s):  
Tahmid Faisal ◽  
Monira Ahsan ◽  
Jakir Ahmed Choudhury ◽  
ATM Zafrul Azam
Keyword(s):  
Brine Shrimp ◽  
High Field ◽  
Methanol Extract ◽  
Methanolic Extract ◽  
Antimicrobial Properties ◽  
Spectroscopic Studies ◽  
Vincristine Sulfate ◽  
Thrombolytic Activity ◽  
Aqueous Fraction ◽  
Lc50 Value

The methanol extract of the powdered leaf of Eurya acuminata was investigated for isolation of secondary metabolites and two compounds were obtained by using VLC, column chromatography and TLC. The compounds were identified as phytol (1) and ?-sitosterol by extensive spectroscopic studies, including high field NMR analyses as well as co-TLC with authentic samples. The methanol extract of leaf of E. acuminata and its organic and aqueous soluble partitioning materials were evaluated for cytotoxic, thrombolytic and antimicrobial properties. In the cytotoxicity study the aqueous fraction of crude methanolic extract showed significant lethality towards brine shrimp having LC50 value 8.821 ?g/ml as compared to standard vincristine sulfate (0.404 ?g/ml). In the study for thrombolytic property, different extract of E. acuminata exhibited various thrombolytic activity ranging from 13.66 to 31.89 % as compared to standard streptokinase (46.51 %). No antimicrobial activity was observed from leaf extracts.Dhaka Univ. J. Pharm. Sci. 15(2): 151-154, 2016 (December)

scholarly journals Antimicrobial and anti-oxidant potential of Periploca hydaspidis

2015 ◽  
Vol 10 (3) ◽  
pp. 645 ◽  
Author(s):  
Rafi Ullah ◽  
Jehan Bakht ◽  
Mohammad Shafi
Keyword(s):  
Antioxidant Activity ◽  
Growth Inhibition ◽  
Methanolic Extract ◽  
Maximum Growth ◽  
Zone Of Inhibition ◽  
Aqueous Fraction ◽  
E Coli ◽  
Methanolic Extracts ◽  
Anti Oxidant ◽  
Diffusion Assay

<p>The present study investigates antimicrobial and anti-oxidant potential of different solvent extracted samples from <em>Periploca hydaspidis </em>through disc diffusion assay. The data revealed that all the extracts reduced the growth of the tested microbes using three different concentrations. <em>Pseudomonas aeruginosa </em>and <em>E. coli</em> were sensitive to crude extracts and all fractions measuring varying degree of growth inhibition.  Similarly, the growth of <em>Citrobacter freundii</em> was not inhibited by crude methanolic extracts, n-hexane, ethyl acetate and aqueous extracted samples. Maximum growth inhibition was measured against <em>Klebsiella pneumoniae</em> exposed to aqueous fraction followed by n-hexane fraction. Our results also suggested that among various fungi, <em>Candida albicans</em> was sensitive to crude methanolic extracts, n-hexane and aqueous fractions compared with other fractions. The rest of the fungi under test were resistant to crude and all fractions showing no zone of inhibition. All the extracted samples of the stems and roots showed antioxidant activity, however, crude methanolic extract of stem tissues exhibited better antioxidant activity than the other extracts.</p>

scholarly journals Temporal dynamics of nonstructural carbohydrates and xylem growth in Pinus sylvestris exposed to drought

2011 ◽  
Vol 41 (8) ◽  
pp. 1590-1597 ◽  
Author(s):  
Walter Oberhuber ◽  
Irene Swidrak ◽  
Daniela Pirkebner ◽  
Andreas Gruber
Keyword(s):  
Pinus Sylvestris ◽  
Temporal Dynamics ◽  
Growing Season ◽  
Cambial Activity ◽  
Wood Formation ◽  
Nonstructural Carbohydrates ◽  
Late Wood ◽  
Structural Growth ◽  
Xylem Growth ◽  
Soil Dryness

Wood formation requires a continuous supply of carbohydrates for structural growth and metabolism. In the montane belt of the central Austrian Alps, we monitored the temporal dynamics of xylem growth and nonstructural carbohydrates (NSC) in stem sapwood of Scots pine ( Pinus sylvestris L.) during the growing season of 2009, which was characterized by exceptional soil dryness within the study area. Soil water content dropped below 10% at the time of maximum xylem growth at the end of May. Histological analyses have been used to describe cambial activity and xylem growth. Determination of NSC was performed using specific enzymatic assays revealing that total NSC ranged from 0.8% to 1.7% dry matter throughout the year. Significant variations (P < 0.05) of the size of the NSC pool were observed during the growing season. Starch showed persistent abundance throughout the year, reaching a maximum shortly before onset of late wood formation in mid-July. Seasonal dynamics of NSC and xylem growth suggest that (i) high sink activity occurred at the start of the growing season in spring and during late wood formation in summer and (ii) there was no particular shortage in NSC, which caused P. sylvestris to draw upon stem reserves more heavily during the drought in 2009.

Cambial phenology in Abies pindrow (Pinaceae) along an altitudinal gradient in northwestern Himalaya

IAWA Journal ◽  
2020 ◽  
Vol 41 (2) ◽  
pp. 186-201
Author(s):  
Rayees Malik ◽  
Sergio Rossi ◽  
Raman Sukumar
Keyword(s):  
Climate Change ◽  
Altitudinal Gradient ◽  
Cell Formation ◽  
Growing Season ◽  
Wood Formation ◽  
Warming Climate ◽  
The World ◽  
Abies Pindrow ◽  
The Himalaya ◽  
Impacts Of Climate Change

Abstract Climate change is expected to be heterogeneous across the world, with high impacts on the Himalayan ecosystems. There is a need to precisely document cambial phenology and wood formation in these regions to better understand climate-growth relationships and how trees face a warming climate. This study describes the dynamics of cambial phenology in pindrow fir (Abies pindrow) along its altitudinal gradient in the Himalaya. The stages of xylem phenology, and the duration and rate of wood formation were assessed from anatomical observations during the growing season from samples collected weekly from three sites at various altitudes (2392–2965 m a.s.l.) over two years. There were significant differences in the duration and rate of cell formation along the altitudinal gradient, which decreased at increasing altitudes. The growing season duration decreased by 5.2 and 3.7 days every 100 m of increase in altitude in 2014 and 2015, respectively, while the rate of cell formation decreased from 0.38 and 0.44 cells /day to 0.29 and 0.34 cells/day in 2014 and 2015, respectively. Cell production decreased from 63.3 and 67.0 cells to 38.3 and 45.2 cells with a decrease of 4.3 and 3.8 cells per 100 m increase in altitude in 2014 and 2015, respectively. The higher precipitation in 2015 increased the growth rate and resulted in a higher xylem production. Our findings give new insights into the dynamics of cambial phenology and help in better understanding of the potential impacts of climate change on tree growth and forest productivity of Himalayan forests.

scholarly journals In Vitro Anticancer MCF-7, Anti-Inflammatory, and Brine Shrimp Lethality Assay (BSLA) and GC-MS Analysis of Whole Plant Butanol Fraction of Rheum ribes (WBFRR)

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Jahangir Khan Achakzai ◽  
Muhammad Anwar Panezai ◽  
Muhammad Ayub Kakar ◽  
Abdul Manan Kakar ◽  
Shahabuddin Kakar ◽  
...  
Keyword(s):  
Cell Line ◽  
Brine Shrimp ◽  
Methanol Extract ◽  
Aqueous Fraction ◽  
Brine Shrimp Lethality ◽  
Butanol Fraction ◽  
Whole Plant ◽  
Brine Shrimp Lethality Assay ◽  
Anti Inflammatory ◽  
Mcf 7

In this study, GC-MS analysis has shown that whole plant butanol fraction of rheum ribes (WBFRR) comprises of 21 compounds which exhibited anticancer (MCF-7) activity having IC50 value of 36.01± 0.26. MTT assay (MCF-7), Oxidative Burst assay using chemiluminescence technique, and B-Hatching techniques were the methods used for anticancer MCF-7, anti-inflammatory, and Brine Shrimp Lethality Assay (BSLA). GC-MS was used for structural elucidation. Whole plant methanol extract of rheum ribes (WMERR), whole plant n-hexane fraction of rheum ribes (WHFRR), and whole plant aqueous fraction of rheum ribes (WAFRR) were inactive against anticancer (MCF-7) cell line. Whole plant methanol extract of rheum ribes (WMERR), whole plant aqueous fraction of rheum ribes (WAFRR) and whole plant butanol fraction of rheum ribes (WBFRR) showed anti-inflammatory activity on ROS having IC50 value of 23.2±1.9, 24.2±2.7 and 12.0±0.6. Whole plant butanol fraction of rheum ribes (WBFRR) showed Brine Shrimp Lethality with LD50 693.302 while whole plant methanol extract of rheum ribes (WMERR) and whole plant aqueous fraction of rheum ribes (WAFRR) showed high lethality at highest concentration. This study revealed that whole plant butanol fraction of rheum ribes (WBFRR) exhibited significant anticancer (MCF-7) activity. In the near future, the constituent of whole plant butanol fraction of rheum ribes (WBFRR) can be the alternative drug against MCF-7 cell line with least toxicity and side effects.

scholarly journals Antibacterial Activity of Defatted and Nondefatted Methanolic Extracts of Aframomum melegueta K. Schum. against Multidrug-Resistant Bacteria of Clinical Importance

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Olufunmiso Olusola Olajuyigbe ◽  
Otunola Adedayo ◽  
Roger Murugas Coopoosamy
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Infections ◽  
Methanol Extract ◽  
Clinical Importance ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Plant Materials ◽  
Methanolic Extracts ◽  
Agar Dilution ◽  
Inhibition Zones

The antibacterial activity of the extracts of Aframomum melegueta including n-hexane extract (NHE), nondefatted methanol extract (NDME), and defatted methanol extract (DME) was investigated in this study. The NHE exhibited no antibacterial activity. The DME showed higher antibacterial activity than the NDME against the different isolates. At the highest concentration of 10 mg/mL in agar diffusion, NDME produced inhibition zones ranging from 11 to 29 mm against the microorganisms while DME produced inhibition zones ranging from 20 to 40 mm with the concentration of 10 mg/mL against the microorganisms. 0.1 mg/mL of the DME produced inhibition zones ranging between 12 and 14 mm in Aeromonas hydrophila ATCC 35654 and Pseudomonas aeruginosa ATCC 15442, respectively, while none of the isolates were inhibited by the NDME at a concentration of 1 mg/mL or less. In the agar dilution assay, the MICs of the NDME and DME ranged between 0.31 and 10 mg/mL, but more isolates were inhibited at 0.31 mg/mL of DME than those in NDME. In macrobroth assay, the MICs of the NDME ranged between 0.15 and 5.0 mg/mL and the MBCs ranged between 0.63 and 5.0 mg/mL, and the MICs of the DME ranged between 0.08 and 5.0 mg/mL and the MBCs were between 0.31 and 5.0 mg/mL. This study indicated that DME was more active with higher antibacterial activity than the NDME of this plant, and extracting the fatty portion of plant materials prior susceptibility testing would allow plant extracts to be more effective as well as justifying the use of Aframomum melegueta in traditional medicine for the treatment of bacterial infections.

THE BIOSYNTHESIS OF INDOLEACETIC ACID IN MELAMPSORA LINI (PERS.) LEV.

1962 ◽  
Vol 40 (2) ◽  
pp. 309-315 ◽  
Author(s):  
B. I. Sahai Srivastava ◽  
Michael Shaw
Keyword(s):  
Incubation Medium ◽  
Plant Material ◽  
Indoleacetic Acid ◽  
Extension Growth ◽  
Tissue Cultures ◽  
Melampsora Lini ◽  
Solvent Systems

Mycelium of Melampsora was grown on flax cotyledons in tissue cultures. Mycelium and uredospores were incubated with DL-tryptophane-2-C14 and uredospores were incubated with L-tryptophane. Acid and neutral ether-soluble and aqueous fractions of the plant material and incubation medium were chromatographed and sprayed with chromogenic agents or radioautographed. Radioactive indoleacetic acid was produced in small amounts by both mycelium and spores (yield = 0.016% in 8 hours). The auxin was identified on the basis of its Rf values in two solvent systems, its reactions with Ehrlich and Salkowski reagents, and its ability to promote extension growth of Avena coleoptiles. Evidence for the formation of indoleacetaldehyde was also obtained. Several other radioactive and Ehrlich-positive products of tryptophane metabolism were detected but not identified. One of these could have been indolepyruvic acid. Tryptamine and indoleacetonitrile were not found. The results suggest that, in Melampsora, the synthesis of indoleacetic acid from tryptophane proceeds through indolepyruvic acid and indoleacetaldehyde.

Neutralization Effect of Tithonia diversifolia (Hemsl.) A. Gray against Bitis arietans and Naja nigricollis venoms-induced toxicity

2020 ◽  
Vol 35 (1) ◽  
pp. 41-50
Author(s):  
Adebayo Gbolade ◽  
Ifunanya Ukaigwe ◽  
Anastasia Omorogbe
Keyword(s):  
Platelet Aggregation ◽  
Methanol Extract ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Adenosine Diphosphate ◽  
Total Phenolic ◽  
Total Phenol Content ◽  
Tithonia Diversifolia ◽  
Aqueous Fraction ◽  
Active Inhibitor

Leaf methanol extract and fractions of Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) used in traditional medicine was evaluated for neutralization of toxicity induced by Bitis arietans and Naja nigricollis snake venoms in mice and rats. Inhibition of adenosine diphosphate-induced platelet aggregation, antioxidant activity, total phenol content and neutralization of venom-induced toxicity were evaluated by standard methods. The methanol extract was the most active inhibitor of platelet aggregation (66.7 - 84.8%) in the B. arietans model at 100 - 500 μg/ml. The methanol extract and fractions appear to be equipotent  in inhibiting platelet aggregation (68 - 74%) induced by N. nigricollis. The aqueous fraction was more active against B. arietans venom at 500 μg/ml as an inhibitor of platelet aggregation (59.4% inhibition), while the dichloromethane (DCM) fraction was more potent against N. nigricollis (70.97% inhibition). The methanol extract showed highest DPPH radical scavenging activity followed by the aqueous and DCM fractions. Total phenolic content was in the order: methanol extract > DCM fraction > aqueous fraction. The aqueous fraction was a better antivenin agent in both B. arietans (complete protection at 24 h) and N. nigricollis-envenomed mice and rat models. Anti-snake venom activity was more prominent at 24 h. The results herein, being the very first report, indicate the potential antiophidic activity of T. diversifolia leaf particularly against B. arietans-induced toxicity.  

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