Nectary structure and nectar presentation in the Mediterranean geophyte, Urginea maritima (Hyacinthaceae)

Botany ◽  
2008 ◽  
Vol 86 (10) ◽  
pp. 1194-1204 ◽  
Author(s):  
Sharaf Al-Tardeh ◽  
Thomas Sawidis ◽  
Barbara-Evelin Diannelidis ◽  
Stylianos Delivopoulos
Keyword(s):  
Intermediate Stage ◽  
Secretory Cells ◽  
Urginea Maritima ◽  
Floral Nectary ◽  
Hydrolysis Process ◽  
Septal Nectary ◽  
Parenchyma Cells ◽  
Subsidiary Cells ◽  
Hydrolysis Of ◽  
Anatomy And Ultrastructure

The morphology, anatomy, and ultrastructure of the floral nectary of Urginea maritima (L.) Baker were investigated at three stages of nectary development. The plant possesses a typical gynopleural (septal) nectary with secondary presentation. The nectary consists of one layer of epithelium secretory cells and one to four layers of subsidiary cells subtended by two to six layers of parenchyma (subnectary) cells. The nectary releases the nectar at a point two-thirds towards the summit of the ovary by means of carpellary sutures. Nectar secretion appears to depend largely on the hydrolysis of starch grains stored in amyloplasts at the intermediate stage. The hydrolysis process most likely commences in the epithelium layer followed by the subsidiary tissue and then the parenchyma cells of the ovary wall. A symplastic transfer of the secreted nectar occurs by plasmodesmata connecting the subsidiary cells to the parenchyma and the epithelial secretory cells. However, microchannels in the cell wall of the epithelial cells may facilitate the apoplastic transfer of the nectar into the nectary cavity. The old stage of nectary development is characterized by a crystallized form of nectar, collapse of the parenchyma cells, complete starch hydrolysis, and disappearance of the amyloplasts and endoplasmic reticulum.

Ontogénie des laticifères du système primaire de l’Hevea brasiliensis: une étude ultrastructurale et cytochimique

1981 ◽  
Vol 59 (6) ◽  
pp. 974-985 ◽  
Author(s):  
Charles Hébant
Keyword(s):  
Endoplasmic Reticulum ◽  
Cell Wall ◽  
Surface Film ◽  
Secretory Cells ◽  
Primary System ◽  
Parenchyma Cells ◽  
Rubber Particles ◽  
Specialized Form ◽  
Hydrolysis Of

The development of the laticifers of the primary system in the roots of young seedlings of Hevea is investigated. The nucleus of the maturing secretory cells progressively diminishes in size, thus giving rise to a dense "pycnotic" body. Plastids of primary laticifers show an organization intermediate between that of plastids of neighbouring parenchyma cells and that of the Frey-Wyssling complexes of the secondary laticifers. The continuity of the vacuome sensu lato is underlined. The lutoids, a specialized form of "polydisperse vacuome," show a relationship with the endoplasmic reticulum; these lutoïds can also incorporate rubber particles. The ontogeny of cell wall perforations is described; a progressive hydrolysis of the wall results in its gradual thinning followed by its disruption. Rubber particles are initiated as discrete inclusions within the protoplasm. A thin surface film is identifiable on them, the staining properties of which change during the maturation of the particles. The protoplasm of adult laticifers is densely packed with rubber particles.

scholarly journals Structure of nectaries of Malus sylvestris (L.) Mill.

2012 ◽  
Vol 59 (1) ◽  
pp. 41-48
Author(s):  
Agata Konarska
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Middle Part ◽  
Epidermal Cells ◽  
Secretory Cells ◽  
Floral Nectary ◽  
Malus Sylvestris ◽  
Parenchyma Cells ◽  
Nectariferous Tissue ◽  
Scanning Electron

The structure of floral nectary of <i>Malus sylvestris</i> was examined using light and scanning electron microscopy. Nectaries in <i>M. sylvestris</i> flowers were situated on the adaxial surface of the receptacle, between the style and the base of filaments. The middle part of the nectary was covered epidermal cells with striated cuticle. The remaining part of the nectary was covered with smooth cuticle. Open and modified nectarostomata were situated at the same level as epidermal cells. The nectariferous tissue was formed by densely packed small parenchyma cells (secretory cells) with dark protoplasts.

scholarly journals Anatomy and ultrastructure of floral nectary of lnula helenium L (Asteraceae)

2011 ◽  
Vol 76 (3) ◽  
pp. 201-207 ◽  
Author(s):  
Aneta Sulborska ◽  
Elżbieta Weryszko-Chmielewska
Keyword(s):  
Secretory Cells ◽  
Secretory Vesicles ◽  
Nectar Secretion ◽  
Golgi Bodies ◽  
Floral Nectary ◽  
Granular Cytoplasm ◽  
Inula Helenium ◽  
Modified Stomata ◽  
Floral Nectaries ◽  
Anatomy And Ultrastructure

Floral nectaries of <em>Inula helenium</em> L. only occurred in disc florets and were situated above the inferior ovary. The shape of the investigated glands (five-armed star with rounded tips and deep incisions - observed from above) clearly differed from the shape of the nectaries of other <em>Asteraceae</em>, also the height of nectary was much lower (129 µm). The glandular tissue of the nectaries of elecampane was composed of a single-layered epidermis and 5--9 layers of secretory cells. Nectar was released through modified stomata, mainly arranged in the top part of the gland. The secretory cells were characterised by granular cytoplasm and the presence of a large, often lobate, cell nucleus. In the cytosol, numerous amoeboid plastids, mitochondria, Golgi bodies and ribosomes were present. In small vacuoles, myelin-like structures, fibrous material and vesicles with the content of substances which can be secretion, were observed. The plastid stroma showed different electron density and the presence of internal tubules and plastoglobules. Vesicular extensions forming bright zones were visible between the membranes of the nuclear envelope. Adjacent to the plasmalemma, as well as between the plasmalemma and the cell wall, secretory vesicles occurred, indicating the granulocrine mechanism of nectar secretion.

scholarly journals The structure of nectary of Platanthera bifolia L. Orchidaceae

2014 ◽  
Vol 66 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Małgorzata Stpiczyńska
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Secretory Cells ◽  
Floral Nectary ◽  
Secretory Tissue ◽  
Characteristic Features ◽  
Anatomy And Ultrastructure

The anatomy and ultrastructure of floral nectary of <em>Platanthera bifolia</em> were studied. The epidermis inside the nectary spur showed characteristic features of secretory tissue. Many cells of this epidermis were protruded forming unicellular hairs. The protoplasts of secretory cells were characterized by few small vacuoles, a lot of mitochondria and leucoplasts, which stored starch before secretion. Numerous vesicles budded off from the endoplasmic reticulum and the Golgi apparatus were accumulated near plasmalemma and fused with it. This fact probably indicates that these structures are involved in secretory processes. Nectar was released onto the surface through the pores in a ruptured cuticle, which covered the walls of secretory hairs.

Antioxidant Activity of Silk Fibroin Peptide Hydrolyzed by Pancreatin

2014 ◽  
Vol 1081 ◽  
pp. 110-114 ◽  
Author(s):  
Zhen Zhu ◽  
Hua Yin ◽  
Yan An
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Nitrogen Content ◽  
Silk Fibroin ◽  
Radical Scavenging ◽  
Amino Nitrogen ◽  
Free Radical Scavenging ◽  
Hydrolysis Process ◽  
Superoxide Free Radical ◽  
Hydrolysis Of

This research adopts the pancreatin hydrolysis of silk fibroin active peptide, evaluate the antioxidant activity of hydrolysates. In the process of hydrolysis of silk fibroin, by measuring the amino nitrogen content of neutral formaldehyde titration method. Find the amino nitrogen content gradually stabilized at around 0.37g/L, and superoxide free radical scavenging rate changing with time fluctuation trend, superoxide free radical scavenging rate to a maximum of 65.03% at 220min.The use of silk fibroin hydrolysis process optimization,reaction time 160min, enzyme concentration4% , substrate concentration 20mg/ml, pH 8, temperature 38°C. The hydrolysis process under the hydrolysate on superoxide radical scavenging rate of 72.73%. The scavenging rate of hydroxyl radical is 47.24%. Red blood cell hemolysis induced by H2O2 inhibition rate was 24.30%.

Thermal hydrolysis of waste activated sludge at Hengelo Wastewater Treatment Plant, The Netherlands

2014 ◽  
Vol 70 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Mathijs Oosterhuis ◽  
Davy Ringoot ◽  
Alexander Hendriks ◽  
Paul Roeleveld
Keyword(s):  
Activated Sludge ◽  
Treatment Plant ◽  
Waste Activated Sludge ◽  
Treatment Technique ◽  
Thermal Hydrolysis ◽  
Sludge Treatment ◽  
Water Board ◽  
Anaerobic Biodegradability ◽  
Hydrolysis Process ◽  
Hydrolysis Of

The thermal hydrolysis process (THP) is a sludge treatment technique which affects anaerobic biodegradability, viscosity and dewaterability of waste activated sludge (WAS). In 2011 a THP-pilot plant was operated, connected to laboratory-scale digesters, at the water board Regge en Dinkel and in cooperation with Cambi A.S. and MWH Global. Thermal hydrolysis of WAS resulted in a 62% greater volatile solids (VS) reduction compared to non-hydrolysed sludge. Furthermore, the pilot digesters could be operated at a 2.3 times higher solids loading rate compared to conventional sludge digesters. By application of thermal sludge hydrolysis, the overall efficiency of the sludge treatment process can be improved.

scholarly journals Hydrolysis Activity of Virgin Coconut Oil Using Lipase from Different Sources

Scientifica ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
T. A. V. Nguyen ◽  
Truong D. Le ◽  
Hoa N. Phan ◽  
Lam B. Tran
Keyword(s):  
Time Course ◽  
Candida Rugosa ◽  
Coconut Oil ◽  
Virgin Coconut Oil ◽  
Porcine Pancreas ◽  
Hydrolysis Degree ◽  
Porcine Pancreas Lipase ◽  
Hydrolysis Process ◽  
Hydrolysis Of ◽  
Different Sources

Two types of lipase, Candida rugosa lipase (CRL) and porcine pancreas lipase (PPL), were used to hydrolyze virgin coconut oil (VCO). The hydrolysis process was carried out under four parameters, VCO to buffer ratio, lipase concentration, pH, and temperature, which have a significant effect on hydrolysis of lipase. CRL obtained the best hydrolysis condition at 1 : 5 of VCO to buffer ratio, 1.5% of CRL concentration, pH 7, and temperature of 40°C. Meanwhile, PPL gave different results at 1 : 4 of VCO to buffer ratio, 2% of lipase concentration, pH 7.5, and 40°C. The highest hydrolysis degree of CRL and PPL was obtained after 16 hours and 26 hours, reaching 79.64% and 27.94%, respectively. Besides, the hydrolysis process was controlled at different time course (every half an hour) at the first 4 hours of reaction to compare the initial hydrolysis degree of these two lipase types. FFAs from hydrolyzed products were isolated and determined the percentage of each fatty acid which contributes to the FFAs mixture. As a result, medium chain fatty acids (MCFAs) made up the main contribution in composition of FFAs and lauric acid (C12) was the largest segment (47.23% for CRL and 44.23% for PPL).

scholarly journals Enzymatic hydrolysis of oil palm empty fruit bunch to produce reducing sugar and its kinetic Hidrolisis enzimatik tandan kosong kelapa sawit untuk menghasilkan gula pereduksi dan kinetikanya

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Vera BARLIANTI ◽  
Deliana DAHNUM ◽  
. MURYANTO ◽  
Eka TRIWAHYUNI ◽  
Yosi ARISTIAWAN ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Oil Palm ◽  
Volume Ratio ◽  
Enzyme Concentration ◽  
Reducing Sugar ◽  
Economic Feasibility ◽  
First Order ◽  
Empty Fruit Bunches ◽  
Hydrolysis Process ◽  
Hydrolysis Of

Abstrak Sebagai salah satu Negara penghasil minyak kelapa sawit mentah (CPO), Indonesia juga menghasilkan tandan kosong kelapa sawit (TKKS) dalam jumlah besar. TKKS terdiri dari-tiga-komponen utama, yaitu selulosa, hemiselulosa, dan lignin. Pengolahan awal TKKS secara alkalindi ikuti dengan hidrolisis TKKS secara enzimatik menggunakan kombinasi enzim selulase dan β-glukosidase akan menghasilkan gula-gula yang mudah difermentasi.  Penelitian ini bertujuan untuk mempelajari pengaruh konsentrasi substrat, kon-sentrasi enzim, dan suhu selama proses hidrolisis berlangsung.  Hasil yang diperoleh menunjukkan bahwa konsentrasi gula maksimum (194,78 g/L) dicapai pada konsentrasi TKKS 20% (b/v), konsentrasi campuran enzim yang terdiri dari selulase dan β-1,4 glukosidase sebesar 3,85% (v/v), dan suhu 50oC. Perbandingan antara selulase dan β-1,4 glukosidase adalah 5:1 dengan masing-masing aktivitas enzim sebesar 144.5 FPU/mL dan 63 FPU/mL. Hasil penelitian juga menunjukkan bahwa model kinetika yang sesuai untuk proses hidrolisis TKKS secara enzimatik adalah model kinetika Shen dan Agblevor dengan reakside aktivasi enzim orde satu.  Hasil ini mendukung studi kelayakan ekonomi dalam pemanfaatan TKKS untuk produksi bioetanol.AbstractAs one of the crude palm oil producers, Indonesia also produces empty fruit bunches (EFB)in large quantities. The oil palm EFB consist of cellulose, hemicellulose and lignin. Alkaline pretreatment of EFB, followed by enzymatic hydro-lysis of cellulose using combination of cellulase and β-glucosidase enzymes produce fermentable sugars. This paper reported the effects of substrate loading, enzyme concentration, and temperature of hydrolysis process on reducing sugar production. The  maximum  sugar  concentration (194.78 g/L) was produced at 50oC using 20% (w/v) EFB and 3.85% (v/v) mixed enzymes of cellulase and β-1,4 glucosidase in volume ratio of 5:1 (v/v), with enzyme activity of 144.5 FPU/mL and 63 FPU/mL, respectively. The results also showed that the suitable kinetic model for enzymatic hydrolysis process of oil palm EFB follow Shen and Agblevor model with first order of enzyme deactivation. These results support the economic feasibility study in utilization of EFB of oil palm for bioethanol production.    

scholarly journals Preparation and Characterization of Sulfonated Carbon from Candlenut Shell as Catalyst for Hydrolysis of Cogon Grass Cellulose into Glucose

2020 ◽  
Vol 32 (6) ◽  
pp. 1404-1408
Author(s):  
Taslim ◽  
Dian Halimah Batubara ◽  
Seri Maulina ◽  
Iriany ◽  
Okta Bani
Keyword(s):  
Solid Acid ◽  
Batch Reactor ◽  
Solid Acid Catalyst ◽  
Acid Catalyst ◽  
Cellulose Hydrolysis ◽  
Imperata Cylindrica ◽  
Hydrolysis Process ◽  
Catalyst Production ◽  
Hydrolysis Of

Cogon grass (Imperata cylindrica) is convertible into glucose by hydrolysis process, which usually requires a catalyst. A solid acid catalyst of sulfonated carbon was used in this work. This study aimed to observe the viability of candlenut shell as carbonaceous source in solid acid catalyst production and to characterize the sulfonated carbon. The carbonization was performed at 250-550 ºC for 4 h, while sulfonation was carried out at 100-180 ºC for 6 h. Sulfonated carbon was then characterized by H+ activity/acid density test, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) and Fourier transform infrared (FTIR) spectroscopy. Sulfonated carbon was then tested as a heterogeneous catalyst for hydrolysis reaction. The reaction was performed in a stainless steel batch reactor at 100 ºC for 6 h. Glucose formed by hydrolysis was measured by dinitrosalicylic acid (DNS) method. Results of this study suggested that sulfonated carbon derived from candlenut shell may be used as a catalyst for cogon grass cellulose hydrolysis to produce glucose

Effects of gas composition and pH on kinetics of lung angiotensin-converting enzyme

1987 ◽  
Vol 62 (3) ◽  
pp. 1216-1221 ◽  
Author(s):  
D. A. Rickaby ◽  
R. D. Bongard ◽  
M. J. Tristani ◽  
J. H. Linehan ◽  
C. A. Dawson
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Surface Area ◽  
Ph Dependence ◽  
Gas Composition ◽  
Converting Enzyme ◽  
Hydrolysis Process ◽  
Hypoxic Vasoconstriction ◽  
Ace Activity ◽  
Kinetics Of ◽  
Hydrolysis Of

Given the pH dependence of enzymes in general and the potential importance of a blood and alveolar gas composition dependency on the interpretation of changes in the hydrolysis of angiotensin-converting enzyme (ACE) substrates by pulmonary endothelial ACE, we examined the influence of Pco2 and Po2 on the hydrolysis of a synthetic ACE substrate (benzoyl-phenylalanyl-alanyl-proline, BPAP) on passage through isolated rabbit lungs. Perfusate pH values of about 7.1, 7.4, and 7.9 were obtained by ventilating the lungs with gas containing different CO2 concentrations and Po2 values of approximately 110 and approximately 10 Torr were obtained by varying the concentration of O2 in the ventilating gas mixture. In the range studied neither acidosis nor alkalosis produced any significant changes in BPAP hydrolysis or in the kinetic parameters, Vmax and Km, for the hydrolysis process. On the other hand, a reduction in BPAP hydrolysis was detected when the Po2 was reduced from 110 to 10 Torr. The Vmax for BPAP hydrolysis by the lung was inversely correlated with the magnitude of the hypoxic vasoconstriction that occurred, suggesting that the reduced BPAP hydrolysis with hypoxia was due to the loss of perfused surface area due to the vasoconstriction. The results suggest that correlations between Pco2 and/or pH and whole-lung ACE activity that might occur in diseased lungs do not imply causalty. The hemodynamic consequences of changing Po2 (i.e., hypoxic vasoconstriction) may alter whole-organ ACE activity in the sense of changing the perfused surface area (i.e., the amount of ACE in contact with flowing perfusate).

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