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Functional foods find a very important place in the modern era, where different types of cancer, diabetes, cardiovascular diseases, etc. are on a high. Irrespective of the abundance of bioactive components in different fruits and vegetables, their low solubility in aqueous solution, vulnerability to destruction in different environmental and gastrointestinal conditions and a low intestinal absorption becomes a concern. Because it is quite difficult to commercialize non food materials for the food encapsulation purposes due to their safety concerns in the human body, scientists in the recent times have come up with the idea of encapsulating the different bioactive components in different food grade materials that are able to safeguard these bioactive components against the different environmental and gastrointestinal conditions and ensure their safe and targeted delivery at their absorption sites. Different food grade encapsulation materials including various oligosaccharides, polysaccharides (starch, cyclodextrins, alginates, chitosan, gum arabic, and carboxymethyl cellulose) and proteins and their suitability for encapsulating various bioactive components like flavonoids (catechins, rutin, curcumin, hesperetin, and vanillin), nonflavonoids (resveratrol), carotenoids (β-carotene, lycopene, and lutein), and fatty acids (fish oil, flaxseed oil, and olive oil) of high medical and nutritional value are reviewed here.  相似文献   
996.
The natural products are gaining immense importance in the domain of nutrition to prevent various maladies and improve the quality of life. Among these, natural exudates are of significant worth as these biochemical compounds are released by various living entities having pharmacological properties for utilization in various drug developments. These natural exudates are the promising source for the discovery of new medications. Numerous bioactive moieties collected by honeybees from exudates and buds of particular trees and plants, considered to be utilized as defensive barrier with special reference to propolis. It generally contains numerous biochemical components, i.e., polyphenols, steroids, terpenoids, and amino acids. They also contain isoferulic acid, sinapinic acid, caffeic acid, and chrysin responsible for antibacterial perspectives. With special attention to propolis, it has been utilized in folk medicines due to several of its therapeutic activities, i.e., antioxidant, antidiabetic, anti-inflammatory, antiviral, and anticancer properties. In this context, it is extensively used in foodstuffs and beverages to improve health related disorders like inflammation, diabetes, heart disease, protects injured gums, and cancer insurgence. Moreover, it has been used to curtail stomatology, gastroenterology, skin lesions, and otorhinolaryngologic and respiration diseases.  相似文献   
997.
The popping process was optimized for brown rice based on an expansion ratio. A central composite design with interactive effect of three independent variables, including salt content (1–2.5 g/100 g raw material), moisture content (13–17 g/100 g raw material), and popping temperature (210–240°C) was used to study their effects on the expansion ratio of rice using response surface methodology. The experimental values of expansion ratio were ranged from 5.24 to 6.85. On fitting the experimental values of expansion ratio to a second order polynomial equation, a mathematical model with the predictability was developed with the statistical adequacy and validity (p ? 0.05). From the model, the optimal condition including salt content (1.75 g/100 g raw material), moisture content (15 g/100 g raw material), and popping temperature (225°C) were predicted for a maximum expansion ratio of 6.79, which was then proved to be 6.85 through experiment. Raw and popped brown rice were investigated for physical properties including hardness, L*, a*, and b* value, length/breadth ratio, bulk density, and minerals, which showed the significant differences. The optimized popped rice sample was evaluated for structural, spectroscopic, and thermal properties, which showed the significant difference from raw rice.  相似文献   
998.
Hydrocolloids act as stabilizer and thickening agents, thus able to replace emulsifying salts. The present study was planned to use к-carrageenan in the production of processed cheddar cheese and to explore its effect on physico-chemical and textural properties of processed cheddar cheeses. Different concentration of ?-carrageenan were used with gradual decrease in salt contents along with natural cheese, fat, and water to prepare processed cheddar cheese. The prepared samples were analyzed for physico-chemical and sensory attributes at storage interval of 45 days during and after 90 days. With the increase in hydrocolloid concentration, stiffer product was obtained and meltability of the samples decreased than control. Processed cheddar cheese samples having 0.15% к-carrageenan with 2% emulsifying salt (1.34% sodium citrate and 0.66% disodium phosphates) were found more acceptable in terms of physico-chemical and sensory attributes, but all sensory attributes got fewer score with the passage of storage time.  相似文献   
999.
Microemulsions are isotropic, thermodynamically stable transparent (or translucent) systems of oil, water, and surfactant, frequently in combination with a cosurfactant with a droplet size usually in the range of 20–200 nm. Since their discovery, they have attained increasing significance both in basic research and in industry. Due to their distinct advantages such as enhanced drug solubility, thermodynamic stability, facile preparation, and low cost, uses and applications of microemulsions have been numerous. Recently, there is a surge in the exploration of microemulsion for transdermal drug delivery for their ability to incorporate both hydrophilic (5-fluorouracil, apomorphine hydrochloride, diphenhydramine hydrochloride, tetracaine hydrochloride, and methotrexate) and lipophilic drugs (estradiol, finasteride, ketoprofen, meloxicam, felodipine, and triptolide) and enhance their permeation. Very low surface tension in conjunction with enormous increase in the interfacial area due to nanosized droplets of the microemulsion influences the drug permeation across the skin. A large number of oils and surfactants are available, which can be used as components of microemulsion systems for transdermal delivery but their toxicity, irritation potential, and unclear mechanism of action limit their use. Besides surfactants, oils can also act as penetration enhancers (oleic acid, linoleic acid, isopropyl myristate, isopropyl palmitate, etc.). The transdermal drug delivery potential of microemulsions is dependent not only on the applied constituents of the vehicle but also drastically on the composition/internal structure of the phases which may promote or hamper the drug distribution in the vehicles. This article explores microemulsion as transdermal drug delivery vehicles with emphasis on components selection for enhanced drug permeation and skin tolerability of these systems and further future directions.  相似文献   
1000.
In this paper, the simulation of 60 GHz millimeter-wave radio over fiber link with 4-QAM OFDM modulation format at 40 Gb/s over 150 km SMF is proposed. The 60 GHz millimeter-wave signal is generated by the optical heterodyne method. Coherent detection has been used at the receiver to down-convert millimeter-wave signal to IF band. Introduction of the OFDM modulation in RoF-based system realizes the benefits of higher order modulations (such as 4-QAM, 16-QAM, etc.) to ensure the good spectral efficiency and multi-gigabit access. The performance of the system is analyzed by Q-factor and BER by which it can be shown that the best results are obtained at the input power of 10 dBm. The simulation results clearly demonstrate the feasibility of this 4-QAM OFDM RoF system over 150 km fiber link.  相似文献   
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