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Seed Germination Performance and Seed Coat Mucilage Production of Sweet Basil (Ocimum basilicum L.)Zhou, Dongfang 03 December 2012 (has links)
Sweet basil (Ocimum basilicum L.) is a warm season herb usually propagated from seeds. Establishment of basil is difficult as seed germination may be limited, particularly during field seeding at cold soil temperatures. The germination of six cultivars (\'Italian Large Leaf\', \'Italian Large Leaf\' 35X, \'Nufar\', \'Genovese\', \'Genovese Compact Improved\' and \'Aroma 2\') of sweet basil seeds were tested on a one dimensional thermo-gradient table over temperatures ranging from 0 to 50"C. At temperatures below 20"C, germination among cultivars was more variable and the mean time to germination (MTG) increased to greater than 25 days for some cultivars. Germination declined sharply and had a sudden termination at high temperatures above 40"C for all six cultivars. There were statistical differences among the cultivar base temperatures, which ranged between 10.1 and 13.3"C. The optimal and ceiling temperatures for germination were similar and did not differ statistically among the cultivars compared in this study. The average optimal temperature for all cultivars was 35 ± 0"C, while the average ceiling temperature was 43 ± 1.3"C. Stored seeds (> 5 years) had lower seed vigor and lower germination percentage, also lower ceiling temperature compared with the fresh seeds of the same cultivar (\'Italian Large Leaf\'), but the base temperatures were the same for both new and old seeds.
Sweet basil (Ocimum basilicum L.) seeds produce a thick layer of mucilage around the pericarp within minutes after hydration. Mucilage is most prevalent among plant species adapted to surviving in arid sandy soils, though its significance in determining ecological fitness is unclear. The mucilage produced by seeds is reported to be composed of cell-wall polysaccharides that are deposited in testa pericarp cells during development. In this study, sweet basil seeds were examined using light and environmental scanning electron microscopy. The mucilage of basil seeds is held together by columnar structures that unfolded from the pericarp and helped hold and stabilize the mucilage to the outer surface. The mucilage was removed using diluted hydrochloric acid to compare performance of seeds with and without mucilage. Mucilage removal did not inhibit seed germination under ideal laboratory conditions but decreased the water content of seeds significantly. The water content of intact seeds was almost 4 times greater than seeds without mucilage. Mucilage enabled seeds cling to an incline board set to a steeper angle than seeds without mucilage. The fully hydrated seeds approached zero water potential, so the mucilage did not prevent seeds from fully hydrating. Soil (media) germination testing showed the seeds with mucilage had higher germination percentage than the seed without mucilage on several different types of media. Seeds with mucilage also had higher survival percentages after 10 days on different types of media. Basil seeds mucilage acts as a reservoir to hold loosely bound water at high water potential so it is available for seed germination and early seedling development. / Master of Science
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Quince seed mucilage-based scaffold as a smart biological substrate to mimic mechanobiological behavior of skin and promote fibroblasts proliferation and h-ASCs differentiation into keratinocytesIzadyari Aghmiuni, A., Heidari Keshel, S., Sefat, Farshid, Akbarzadeh Khiyavi, A. 22 February 2021 (has links)
Yes / The use of biological macromolecules like quince seed mucilage (QSM), as the common curative practice has a long history in traditional folk medicine to cure wounds and burns. However, this gel cannot be applied on exudative wounds because of the high water content and non-absorption of infection of open wounds. It also limits cell-to-cell interactions and leads to the slow wound healing process. In this study to overcome these problems, a novel QSM-based hybrid scaffold modified by PCL/PEG copolymer was designed and characterized. The properties of this scaffold (PCL/QSM/PEG) were also compared with four scaffolds of PCL/PEG, PCL/Chitosan/PEG, chitosan, and QSM, to assess the role of QSM and the combined effect of polymers in improving the function of skin tissue-engineered scaffolds. It was found, the physicochemical properties play a crucial role in regulating cell behaviors so that, PCL/QSM/PEG as a smart/stimuli-responsive bio-matrix promotes not only human-adipose stem cells (h-ASCs) adhesion but also supports fibroblasts growth, via providing a porous-network. PCL/QSM/PEG could also induce keratinocytes at a desirable level for wound healing, by increasing the mechanobiological signals. Immunocytochemistry analysis confirmed keratinocytes differentiation pattern and their normal phenotype on PCL/QSM/PEG. Our study demonstrates, QSM as a differentiation/growth-promoting biological factor can be a proper candidate for design of wound dressings and skin tissue-engineered substrates containing cell.
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IMPROVEMENT OF FUNCTIONAL AND BIOACTIVE PROPERTIES OF CHIA SEED (SALVIA HISPANICA) PROTEIN HYDROLYSATES AND DEVELOPMENT OF BIODEGRADABLE FILMS USING CHIA SEED MUCILAGEUriel C Urbizo Reyes (7909295) 14 January 2021 (has links)
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<p>Chia seed (<i>Salvia hispanica</i>)
has shown potential as an alternative source of nutrients with a high content
of fiber (36 %), protein (25%), and fat (25%). Unfortunately, the presence of a
viscous biopolymer (mucilage), surrounding the chia seed (CS), limits the
accessibility of the protein and other nutrients. Nevertheless, this
biopolymer’s chemical composition makes it suitable for the development of
biodegradable films. Regarding CS protein, disulfide bonding, and
nonprotein-protein interactions often frequent in plant protein, have limited
its technological application in food matrices. Therefore, scientists have
pointed at processing methods involving enzymatic proteolysis to improve the
functionality of plant protein ingredients. The objective of this study was to
establish processing techniques to exploit the functionality, extraction, and
health benefits of chia seed components. First, ultrasonication followed by
vacuum-filtration was used to separate mucilage from CS prior to fat extraction
by oil press. Mucilage-free and defatted CS were treated using conventional
(enzymatic hydrolysis with alcalase) or sequential (enzymatic hydrolysis with
alcalase+flavourzyme), and under water bath or microwave-assisted hydrolysis.
Chia seed protein hydrolysates (CSPH) derived from the sequential hydrolysis
with microwave treatment showed superior (p<0.05) in vitro antioxidant
activity. The highest (p<0.05) cellular antioxidant activity was achieved by
the sequential (94.76%) and conventional (93.13%) hydrolysis with microwave.
Dipeptidyl peptidase-V inhibition was higher (p<0.05) for sequential
hydrolysis with water bath, while Angiotensin-Converting Enzyme (ACE)
inhibition activity increased (p<0.05) with hydrolysis for all treatments
compared to the control. Regarding functionality, sequential hydrolysis with
microwave showed higher (p<0.05) solubility at lower pH (3 and 5), while
conventional hydrolysis with microwave was better at pH 7 and 9. Emulsification
properties and foaming capacity were also higher in conventional hydrolysis with
microwave, but conventional hydrolysis with water bath was more stable for
foaming properties only. In terms of mucilage applicability, biodegradable
films were developed by casting technique where CS mucilage was plasticized
with different polyol mixtures (sorbitol and glycerol). CS mucilage films with
higher sorbitol content showed superior tensile strength (3.23 N/mm<sup>2</sup>),
and lower water vapor permeability (1.3*109 g/ m*s*Pa) but had poor flexibility
compared to other treatments. Conversely, films with high glycerol content
showed high elongation at break (67.55%) and solubility (22.75%), but reduced
water vapor permeability and tensile strength. The hydrophobicity, measured as
water contact angle, was higher (p<0.05) for mixtures containing equal
amounts of polyols. Lastly, Raman Spectroscopy analysis showed shifts from 854
to 872 cm<sup>-1</sup> and 1061 to 1076 cm<sup>-1</sup>, which corresponded to
β(CCO) modes. These shifts represent an increase in hydrogen bonding,
responsible for the high tensile strength and decreased water vapor
permeability. This study demonstrated that ultrasonication followed by vacuum
filtration can successfully separate mucilage from chia seeds;
microwave-assisted and enzymatic hydrolysis generated protein hydrolysates with
improved bioactivity and functionality. Finally, chia seed mucilage was able to
form films with potential to be used in drug delivery and edible food coating
applications.</p>
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