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1.
Foods ; 13(7)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38611397

ABSTRACT

Oranges contain many natural active chemicals, organic acids, and polysaccharides. Aging processing is commonly used to modify the color, quality, functional components, and stability of fruits. This study assesses the preparation of aging black oranges using various pre-treatments and solid fermentation. Oranges were aged for six weeks in fresh, non-blanching, blanching, and hot air-assisted aging cycle (AA) groups. The oranges' shrinkage ratio, color difference values, and soluble solids content changed significantly (p < 0.05). Principal component analysis indicated that aging fermentation treatment accelerated glycolysis and increased the ratio of reducing sugars. The enhanced browning can be associated with the oxidation of ascorbic acid (0.66-0.47 mg/g) and the formation of 5-hydroxymethylfurfural (5-HMF) (0.09 mg/g). Furthermore, the presence of free polyphenols led to an increase in the total polyphenol and total flavonoid content. It also had a synergistic effect with 5-HMF in increasing the 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging capacity and ferric ion-reducing antioxidant power (p < 0.05). AA had superior α-glucosidase inhibitory ability increasing from 67.31 to 80.48%. It also reduced the development time by 33%. Therefore, aging technology can enhance the bioactive compounds in oranges and provide a reference for future whole-fruit aging fermentation and health product creation.

2.
Food Chem X ; 21: 101227, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38420504

ABSTRACT

Ginger-infused sesame oil enriches the nutrition and provides enhanced flavor for the foods. An original processing procedure and module for evaluation were established in this study, using different raw materials (Guangdong and Chu ginger) and treatments (ginger powder, extract, and both). The quality, functionality, and flavor of the infused oils were evaluated. Ginger-infused sesame oil contained 0.58-3.22 µg/g of 6-gingerol, 0.21-0.88 µg/g of 6-shogaol. The number range of volatile compounds from 48 to 55 identified by gas chromatography-mass spectrometry varies depending on different process procedures. Agglomerative hierarchical clustering analysis revealed the flavor profiles were clustered by different varieties, while gingerol and phytosterol was by different treatments. In conclusion, sesame oil was an appropriate carrier for gingerol and phytosterol, which are characterized by higher antioxidant capacities (p < 0.05). These results show the benefits of developing infused oil products with enhanced functional and sensory properties.

3.
Life (Basel) ; 13(10)2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37895444

ABSTRACT

Rice (Oryza sativa L.) is an important food crop in Taiwan, among which fragrant rice is highly regarded for its special aroma when cooked. During the storage of fragrant rice, the aroma components will change, which will affect the aroma quality of fragrant rice. Therefore, headspace solid-phase microextraction (HS-SPME) was used in this study, combined with gas chromatography and gas chromatography-mass spectrometry, to analyze the difference in the aroma components of Taikeng No. 4 (TK4), Tainung No. 71 (TN71), Kaohsiung No. 147 (KH147), and Taichung No. 194 (TC194) fragrant rice. A total of 28 aroma components were identified in the four varieties of fragrant rice, and the main components were all Nonanal. Among them, TK4 contains a very high content of hydrocarbons, including Tridecane and Dodecane; TN71, KH147, and TC194 contain mainly aldehydes such as Nonanal and Hexanal. During different storage times, the contents of alcohols, monoterpenes, aromatic aldehydes, and furans increased with storage time, while the content of aliphatic aldehydes decreased with storage time. After storage, the fragrant rice samples showed a tendency for the total volatile component content to decrease, with the most pronounced reduction observed in Nonanal content.

4.
Sci Rep ; 13(1): 501, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36627306

ABSTRACT

Penghu cactus (Opuntia dillenii [Ker.] Haw) is a cactus plant that commonly grows in Penghu Island, Taiwan, Republic of China (ROC). However, still lack of scientific study on the Opuntia dillenii [Ker.] Haw extract on skin-whitening-associated tyrosinase activity and melanin production. The activities of its extract in melanogenesis were investigated in this article. In this experiment, we used an extract from the Penghu cactus (Opuntia dillenii [Ker.] Haw) to study its tyrosinase inhibition, anti-melanin generation, UV-protection effects and wound healing capacity in B16-F10 melanocytes. Without reducing cell growth greatly or causing cell death, 20 g/L cactus extract effectively inhibited the melanin production of B16-F10 cells, and melanogenesis was induced by 3-isobutyl-1-methylxanthine. The cactus extract could also promote cell proliferation. Cactus extract treatment decreased the mRNA expression of insulin-like growth factor 1 (IGF-1) and vascular endothelial growth factor (VEGF) and increased that of transforming growth factor ß (TGF-ß). Thus, it could reduce cell melanin production and promote cell growth but by also reducing IGF-1 and VEGF mRNA expression, may reduce wound scarring and prevent tumor proliferation and swelling. Increasing TGF-ß mRNA expression can help increase collagen to remove wrinkles and help in wound healing. Skin patch test results agreed with in vitro results with B16-F10 melanoma cells. The cactus extract significantly inhibited tyrosinase activity and reduced melanin production, showing a whitening effect on skin tests. Cactus may be a good natural candidate for inhibiting melanin production and promoting cell proliferation.


Subject(s)
Cosmetics , Melanoma, Experimental , Opuntia , Animals , Plant Extracts/pharmacology , Insulin-Like Growth Factor I , Vascular Endothelial Growth Factor A , Monophenol Monooxygenase , Melanocytes , Melanins , RNA, Messenger , Transforming Growth Factor beta , Melanoma, Experimental/drug therapy , Cell Line, Tumor
5.
Molecules ; 27(20)2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36296404

ABSTRACT

Arachis hypogaea L. 'Tainan 14' has purple skin characteristics. This study investigated the effects of different materials (shelled or unshelled peanuts) and temperatures (120 or 140 °C) on the properties of extracted peanut oil. The results show that its antioxidant components (total flavonoid, α−tocopherol, and γ-tocopherol) and oxidative stability were mainly affected by the roasting temperature (p < 0.05). Fifty-eight volatile compounds were identified by peanut oil oxidation and divided into three main groups during the roasting process using principal component analysis. The volatile formation changes of different materials and temperatures were assessed by agglomerative hierarchical clustering analysis. These results provide useful reference information for peanut oil applications in the food industry.


Subject(s)
Antioxidants , Arachis , alpha-Tocopherol , Arachis/chemistry , Flavonoids , gamma-Tocopherol , Peanut Oil , Oxidation-Reduction
6.
Food Chem ; 394: 133442, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-35717923

ABSTRACT

Multiple-layer coating technology has widely applied to the quality modification of bioactive ingredients nowadays. This research used a rotary side-spray fluid bed to manufacture chlorophyll multiple-layer particles to adjust control release characteristics. The chlorophyll extracts were coated with sodium alginate (A1) and sodium caseinate (CA1) as the primary layer on sugar spheres and the product yield was 96.98 and 96.71%, respectively. The content of chlorophyll a and b (µg/g) were 41.04 and 13.20 in A1, 47.40 and 13.68 in CA1. The Fourier-transform infrared spectroscopy confirmed the bonding change and increase stability. The CA1 was coated with sodium alginate (CA-A), sodium carboxymethylcellulose (CA-C) and xanthan gum (CA-X) as the secondary layer, which can increase coated integrity, shell strength and thermal stability. The simulated gastrointestinal fluid showed 30.11% release in the stomach and 94.27% in the intestine, which improved release control characteristics. Increased retention rate and color stability in the storage test.


Subject(s)
Caseins , Chlorophyll , Alginates/chemistry , Caseins/chemistry , Chlorophyll A , Technology
7.
Foods ; 10(11)2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34828881

ABSTRACT

Roasting can increase the Maillard reaction and caramelization of sweet potatoes to create an attractive appearance, color, aroma, and taste, and is rapidly increasing in the commercial market. This study mainly analyzed the influence of roasting sweet potatoes, with and without the peel, on sweet potato quality and flavor characteristics combined with sensory qualities. The results showed that the a* value (1.65-8.10), browning degree (58.30-108.91), total acidity (0.14-0.21 g/100 g, DW), and maltose content (0.00-46.16 g/100 g, DW) of roasted sweet potatoes increased with roasting time. A total of 46 volatile compounds were detected and 2-furanmethanol, furfural, and maltol were identified as the main sources of the aroma of roasted sweet potatoes. A sensory evaluation based on a comprehensive nine-point acceptance test and descriptive analysis showed that roasting for 1 to 2 h resulted in the highest acceptance score (6.20-6.65), including a golden-yellow color, sweet taste, and fibrous texture. The sweet potatoes became brown after roasting for 2.5 to 3 h and gained a burnt and sour taste, which reduced the acceptance score (4.65-5.75). These results can provide a reference for increased quality in the food industry production of roasted sweet potatoes.

8.
Molecules ; 26(11)2021 May 31.
Article in English | MEDLINE | ID: mdl-34072807

ABSTRACT

Peanut oil is favored by consumers due to its rich nutritional value and unique flavor. This study used headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) to examine the differences in the peanut oil aroma on the basis of variety, roasting temperatures, and pressing components. The results revealed that the optimal conditions for extracting peanut oil were achieved through the use of 50/30 µm DVB/CAR/PDMS fibers at 60 °C for 50 min. The primary compounds present in peanut oil were pyrazines. When peanuts were roasted, the temperature raised from 120 °C to 140 °C and the content of aldehydes in peanut oil increased; however, the content of aldehydes in No. 9 oil at 160 °C decreased. The components of peanut shell oil varied depending on the peanut variety. The most marked difference was observed in terms of the main compound at the two roasting temperatures. This compound was a pyrazine, and the content increased with the roasting temperature in hekei oils. When the roasting temperature was lower, No. 9 oil contained more fatty acid oxidation products such as hexanal, heptanal, and nonanal. When the roasting temperature increased, No. 9 oil contained more furfural and 5-methylfurfural. Heren oil was easier to oxidize and produced nonanal that possessed a fatty aroma.


Subject(s)
Food Analysis/methods , Peanut Oil/metabolism , Solid Phase Microextraction/methods , Aldehydes/analysis , Arachis/chemistry , Flavoring Agents/analysis , Furaldehyde/analogs & derivatives , Furaldehyde/analysis , Gas Chromatography-Mass Spectrometry , Hot Temperature , Materials Testing , Odorants/analysis , Peanut Oil/chemistry , Pyrazines/chemistry , Taste , Temperature , Volatile Organic Compounds/analysis
9.
Foods ; 8(9)2019 Sep 07.
Article in English | MEDLINE | ID: mdl-31500259

ABSTRACT

Lime peels are mainly obtained from the byproducts of the juice manufacturing industry, which we obtained and used to extract essential oil (2.3%) in order to examine the antioxidant and hypolipidaemic effects. We identified 60 volatile compounds of lime essential oil (LEO) with GC/MS, of which the predominant constituents were limonene, γ-terpinene, and ß-pinene. Lime essential oil was measured according to the DPPH assay and ABTS assay, with IC50 values of 2.36 mg/mL and 0.26 mg/mL, respectively. This study also explored the protective effects of LEO against lipid-induced hyperlipidemia in a rat model. Two groups of rats received oral LEO in doses of 0.74 g/100 g and 2.23 g/100 g with their diets. Eight weeks later, we found that the administration of LEO improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, alanine aminotransferase, and aspartate transaminase levels in the hyperlipidemic rats (p < 0.05). Simultaneously, the LEO improved the health of the rats in terms of obesity, atherogenic index, and fatty liver.

10.
Food Chem ; 287: 133-138, 2019 Jul 30.
Article in English | MEDLINE | ID: mdl-30857682

ABSTRACT

In this study, the effects on the sensory quality and flavor profile of dried longan resulting from smoking it for 104 h were investigated. The results showed that, in terms of the quality of the dried longan. The smoking time influenced the fruit's water activity (0.70-0.92), soluble solids (30-60 。Brix), pH (6.13-6.71), and tendency to change from yellow to brown hues (ΔE: 3.13-12.83). We detected 42 volatile compound variations during smoking, of which 3-methyl-1-butanol, 3,7-dimethyl-1,3,6-octatriene, hydroxy butanone, and 1-octen-3-ol perceived aroma for longan. Aroma characteristics were evaluated smoky effect by agglomerative hierarchical cluster and principal component analysis. Forasmuch phenolic derivatives (smoky flavor) form lignin degradation correlated for the time, and organic compounds via oxidation (or hydrolyzation). We found get the smoky flavor and intermediate moisture of longan in smoked 72 h, which extended sensory and preservation that is beneficial to longan producers.


Subject(s)
Cooking/methods , Fruit/chemistry , Odorants/analysis , Sapindaceae/chemistry , Smoke , Volatile Organic Compounds/analysis
11.
Mar Drugs ; 17(3)2019 Mar 07.
Article in English | MEDLINE | ID: mdl-30866422

ABSTRACT

Self-emulsion improves solubility and bioavailability for γ-oryzanol/algae oil, and alginate beads can be used as controlled release carriers. In this study, self-emulsified alginate beads (SEABs) were prepared with different weight ratios of self-emulsion treatment (5%, 10%, 15%, 20%, and 30%) with alginate. We found that the microstructure with a surfactant of SEABs had a different appearance with alginate-based beads. The encapsulation of γ-oryzanol corresponded with the self-emulsion/alginate ratio, which was 98.93~60.20% with a different formulation of SEABs. During in vitro release, SEABs had the gastric protection of γ-oryzanol/algae oil, because γ-oryzanol and emulsion were not released in the simulated stomach fluid. When the SEABs were transferred to a simulation of the small intestine, they quickly began to swell and dissolve, releasing a higher content of the emulsion. We observed that the emulsion that formed had a bimodal distribution in the simulated intestinal fluid as a result of the hydrogel and emulsion droplets, leading to the formation of large aggregates. These results suggested that γ-oryzanol encapsulation within alginate beads via emulsification combined with gelation can serve as an effective controlled delivery system.


Subject(s)
Alginates/chemistry , Phenylpropionates/chemistry , Alginates/administration & dosage , Animals , Biological Availability , Delayed-Action Preparations/chemistry , Drug Compounding , Emulsions/administration & dosage , Emulsions/chemistry , Gastric Juice/chemistry , Hydrogels , Microspheres , Particle Size , Phenylpropionates/administration & dosage , Sea Cucumbers/chemistry , Solubility
12.
Molecules ; 23(6)2018 Jun 05.
Article in English | MEDLINE | ID: mdl-29874816

ABSTRACT

Roselle is rich in anthocyanins and is traditionally used to prepare a bright red beverage by decoction. However, heat treatment and different pH environments are often encountered during food processing, and these factors are often detrimental to anthocyanins. Therefore, it is very important to understand the influence of pH and heat treatment on anthocyanins for the application of roselle. This study determined the antioxidant properties of roselle extract, explored changes in the color and anthocyanin content in different pH environments, and evaluated the thermal stability of roselle anthocyanins using kinetic equations. The results showed that the roselle extract is rich in anthocyanins and has good antioxidant capacity (DPPH IC50 = 4.06 mg/mL, ABTS IC50 = 3.7 mg/mL). The anthocyanins themselves exhibited a certain degree of heat resistance and good color stability in an acidic environment. In contrast, they degraded very quickly and exhibited significant changes in color in a low-acid environment. The activation energy (Ea) ranges of the anthocyanins in the acidic and low-acid environments were quite different at 55.8⁻95.7 and 31.4⁻74.9 kJ/mol, respectively. Thus, it can be concluded that roselle anthocyanins are susceptible to heat treatment in a low-acid environment, affecting their quality and appearance; however, they can serve as a good source of functional ingredients and color in an acidic environment.


Subject(s)
Anthocyanins/chemistry , Anthocyanins/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Hibiscus/chemistry , Hot Temperature , Color , Drug Stability , Hydrogen-Ion Concentration , Inhibitory Concentration 50 , Kinetics , Plant Extracts/chemistry , Spectrophotometry, Ultraviolet
13.
J Oleo Sci ; 67(4): 389-396, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29526875

ABSTRACT

In this study, the effects of roasting camellia (Camellia oleifera Abel.) seed oils at different temperatures (65°C, 100°C, 120°C, and 140°C) on the oxidative stability and composition of the oils were investigated. The results showed that, in terms of the quality of the oils, the roasting temperature influenced the total phenolic content (which ranged from 1.64~2.45 GAE mg/g for the different oils) and total flavonoid content (which ranged from 0.36~0.45 QE mg/g for the different oils), while the fatty acid profile and tocopherol content were not influenced by the roasting temperature. We also investigated the kinetic parameters of camellia seed oil during oxidation via Rancimat (at temperatures ranging from 110~140°C). It turned out that the natural logarithms of the oxidative stability index (OSI) varied linearly with respect to temperature (R2: 0.958~0.997). This was done on the basis of the Arrhenius equation that indicates that the activation energies (Ea) for oxidative stability are 65.7~78.4 KJ/mol. Simultaneously, we found that increasing the roasting temperature could increase the antioxidant stability of Maillard reaction products in camellia seed oil. The effects of roasting include the assurance that the camellia seed oil so produced will comply with the relevant governmental health codes and standards and have a longer shelf life.


Subject(s)
Camellia/chemistry , Cooking , Food Quality , Oxidation-Reduction , Plant Oils/chemistry , Seeds/chemistry , Temperature , Food Storage , Glycation End Products, Advanced , Plant Oils/standards
14.
Medicines (Basel) ; 4(2)2017 May 08.
Article in English | MEDLINE | ID: mdl-28930243

ABSTRACT

Background: The calamondin (Citrus microcarpa Bunge) and the kumquat (Fortunella crassifolia Swingle) are two small-size citrus fruits that have traditionally been consumed in Taiwan; however, there has been a lack of scientific research regarding the active compounds and functionalities of these fruits. Methods: Analysis of volatile composition of essential oil and phytosterol was carried out using Gas Chromatography-Mass Spectrometry (GC-MS). Flavonoid and limonoid were analyzed by High Performance Liquid Chromatography (HPLC). Moreover, antioxidant capacity from their essential oils and extracts were assessed in vitro. Results: The compositions of the essential oils of both fruits were identified, with the results showing that the calamondin and kumquat contain identified 43 and 44 volatile compounds, respectively. In addition, oxygenated compounds of volatiles accounted for 4.25% and 2.04%, respectively, consistent with the fact that oxygenated compounds are generally found in high content in citrus fruits. In terms of flavonoids, the calamondin exhibited higher content than the kumquat, with disomin-based flavonoids being predominant; on the other hand, phytosterol content of kumquat was higher than that of calamondin, with amyrin being the dominant phytosterol. Both of them contain high amounts of limonoids. The ethanol extracts and essential oils of small-sized citrus fruits have been shown to have antioxidant effects, with those effects being closely related to the flavonoid content of the fruit in question. Conclusions: The present study also reviewed antioxidant activity in terms of specific bioactive compounds in order to find the underlying biological activity of both fruits. The calamondin and kumquat have antioxidant effects, which are in turn very important for the prevention of chronic diseases.

15.
Mar Drugs ; 15(4)2017 Mar 28.
Article in English | MEDLINE | ID: mdl-28350348

ABSTRACT

Different biological sources of n-3 polyunsaturated fatty acids (n-3 PUFA) in mainstream commercial products include algae and fish. Lipid oxidation in n-3 PUFA-rich oil is the most important cause of its deterioration. We investigated the kinetic parameters of n-3 PUFA-rich oil during oxidation via Rancimat (at a temperature range of 70~100 °C). This was done on the basis of the Arrhenius equation, which indicates that the activation energies (Ea) for oxidative stability are 82.84-96.98 KJ/mol. The chemical substrates of different oxidative levels resulting from oxidation via Rancimat at 80 °C were evaluated. At the initiation of oxidation, the tocopherols in the oil degraded very quickly, resulting in diminished protection against further oxidation. Then, the degradation of the fatty acids with n-3 PUFA-rich oil was evident because of decreased levels of PUFA along with increased levels of saturated fatty acids (SFA). The quality deterioration from n-3 PUFA-rich oil at the various oxidative levels was analyzed chemometrically. The anisidine value (p-AV, r: 0.92) and total oxidation value (TOTOX, r: 0.91) exhibited a good linear relationship in a principal component analysis (PCA), while oxidative change and a significant quality change to the induction period (IP) were detected through an agglomerative hierarchical cluster (AHC) analysis.


Subject(s)
Fatty Acids, Omega-3/chemistry , Fatty Acids, Omega-3/metabolism , Fish Oils/chemistry , Fish Oils/metabolism , Animals , Kinetics , Lipid Metabolism/physiology , Oxidation-Reduction , Perciformes/metabolism
16.
J Oleo Sci ; 66(2): 113-122, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-28100886

ABSTRACT

Algae oil and fish oil are n-3 PUFA mainstream commercial products. The various sources for the stability of n-3 PUFA oxidation are influenced by the fatty acid composition, extraction and refined processing. In this study, the oil stability index (OSI) occurs within 2.3 to 7.6 hours with three different n-3 PUFA rich oil. To set the OSI in the Rancimat test as the oil stability limit and observed various degrees of oxidation (0, 25, 50, 75, 100 and 125%). The volatile oxidation compounds were analyzed via headspace-solid phase microextraction (HS-SPME) and GC/MS. We detected 51 volatile compound variations during the oxidation, which were composed of aldehydes, hydrocarbons, cyclic compounds, alcohols, benzene compounds, ketones, furans, ester and pyrrolidine. The off-flavor characteristics can be strongly influenced by the synergy effects of volatile oxidation compounds. Chemometric analysis (PCA and AHC) was applied to identify the sensitive oxidation marker compounds, which included a (E,E)-2,4-heptadienal appropriate marker, via lipid oxidation in the n-3 PUFA rich oil.


Subject(s)
Fatty Acids, Omega-3/chemistry , Fish Oils/chemistry , Solid Phase Microextraction , Volatile Organic Compounds/analysis , Volatile Organic Compounds/chemistry , Gas Chromatography-Mass Spectrometry , Oxidation-Reduction
17.
Ying Yong Sheng Tai Xue Bao ; 26(5): 1419-25, 2015 May.
Article in Chinese | MEDLINE | ID: mdl-26571660

ABSTRACT

A drought-resistant soybean cultivar Jinda 70 and a drought-sensitive soybean cultivar Jindou 26 were taken as test materials. At the grain filling stage, the cultivars were subject to three water treatments including sufficient water supply, light drought stress, and severe drought stress by using pot experiments for research on influence of drought on leaf photosynthetic capacity and root growth of soybeans. The results showed that as the degree of drought stress was aggravated, all of the indices including leaf area, chlorophyll content, net photosynthetic rates (Pn), stomatal conductance (g(s)), transpiration rate (Tr), intercellular CO2 concentration (Ci), plant mass, plant height, seed yield, and harvest index in the two cultivars declined. The root length and root mass increased under light drought stress, and decreased under severe drought stress. Root-shoot ratio ascended as the degree of drought stress was aggravated. Under severe drought stress, the increase of root-shoot ratio of the drought-resistant soybean cultivar Jinda 70 was up to 135.7%, which was higher than the that (116.7%) of the drought-sensitive soybean cultivar Jindou 26. Simultaneously, leaf area and chlorophyll content in Jinda 70 were respectively 69.3% and 85.5% of those in the control, which were better than those of Jindou 26. g(s) and Pn of Jinda 70 respectively declined 67.9% and 77.9%, but still lower than those of Jindou 26. Therefore, the decline range of harvest index of Jinda 70 was 43.8%, which was lower than the range of 78.8% of Jindou 26. The Biplot revealed that under different dry treatments, there were significant positive correlations among the six indexes including leaf area, chlorophyll content, Pn, g(s), Tr, and Ci of the two cultivars. There were also significant positive correlations among the six indices including plant mass, plant height, root length, root mass, seed yield, and harvest index. Root-shoot ratio only had significant positive correlation with root mass and had significant negative correlations with other five indices.


Subject(s)
Droughts , Glycine max/physiology , Photosynthesis , Plant Leaves/physiology , Plant Roots/growth & development , Chlorophyll/analysis , Seeds/growth & development
18.
J Biophotonics ; 4(9): 610-8, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21538996

ABSTRACT

Time-resolved optical coherence tomography (OCT) scanning images of wild-type and mutant fruit flies (Drosophila melanogaster), illustrating the heartbeat patterns for evaluating their cardiac functions, are demonstrated. Based on the heartbeat patterns, the beat rate and the relative phase between the first two heart segments can be evaluated. The OCT scanning results of mutant flies with impaired proteasome function in cardiac muscles show irregular heartbeat patterns and systematically decreased average beat rates, when compared with the regular patterns of ~4.97 beats/s in average beat rate of the wild-type. In both wild-type and proteasome mutant flies, the beatings at different locations in the same heart segment are essentially synchronized. However, between different heart segments, although the beating in the second segment shows a lag in phase behind that of the first segment in a wild-type, in a proteasome mutant, the beating in the second segment becomes significantly leading that of the first segment. Besides the comparison between the wild-type and proteasomal mutant flies, the influences of using different methods for immobilizing flies during OCT scanning on the heart functions are demonstrated.


Subject(s)
Drosophila melanogaster/ultrastructure , Heart/physiology , Image Processing, Computer-Assisted/methods , Muscle Contraction , Tomography, Optical Coherence/methods , Animals , Drosophila melanogaster/classification , Drosophila melanogaster/genetics , Drosophila melanogaster/physiology , Heart Rate/physiology , Image Processing, Computer-Assisted/instrumentation , Mutation , Proteasome Endopeptidase Complex/genetics , Proteasome Endopeptidase Complex/metabolism , Tomography, Optical Coherence/instrumentation
19.
Nanotechnology ; 21(29): 295102, 2010 Jul 23.
Article in English | MEDLINE | ID: mdl-20601768

ABSTRACT

Preparation of a high-concentration Au nanoring (NR) water solution and its applications to the enhancement of image contrast in optical coherence tomography (OCT) and the generation of the photothermal effect in a bio-sample through localized surface plasmon (LSP) resonance are demonstrated. Au NRs are first fabricated on a sapphire substrate with colloidal lithography and secondary sputtering of Au, and then transferred into a water solution through a liftoff process. By controlling the NR geometry, the LSP dipole resonance wavelength in tissue can cover a spectral range of 1300 nm for OCT scanning of deep tissue penetration. The extinction cross sections of the fabricated Au NRs in water are estimated to give levels of 10(-10)-10(-9) cm(2) near their LSP resonance wavelengths. The fabricated Au NRs are then delivered into pig adipose samples for OCT scanning. It is observed that, when resonant Au NRs are delivered into such a sample, LSP resonance-induced Au NR absorption results in a photothermal effect, making the opaque pig adipose cells transparent. Also, the delivered Au NRs in the intercellular substance enhance the image contrast of OCT scanning through LSP resonance-enhanced scattering. By continuously OCT scanning a sample, both photothermal and image contrast enhancement effects are observed. However, by continually scanning a sample with a low scan frequency, only the image contrast enhancement effect is observed.


Subject(s)
Gold/chemistry , Nanostructures/chemistry , Tomography, Optical Coherence/methods , Adipose Tissue/chemistry , Animals , Microscopy, Electron, Scanning , Nanostructures/ultrastructure , Surface Plasmon Resonance , Surface Properties , Swine
20.
Biomed Opt Express ; 1(4): 1060-1073, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-21258530

ABSTRACT

The characterization results of the localized surface plasmon resonance (LSPR) of Au nanorings (NRs) with optical coherence tomography (OCT) are first demonstrated. Then, the diffusion behaviors of Au NRs in mouse liver samples tracked with OCT are shown. For such research, aqueous solutions of Au NRs with two different localized surface plasmon resonance (LSPR) wavelengths are prepared and characterized. Their LSPR-induced extinction cross sections at 1310 nm are estimated with OCT scanning of solution droplets on coverslip to show reasonably consistent results with the data at individual LSPR wavelengths and at 1310 nm obtained from transmission measurements of Au NR solutions and numerical simulations. The resonant and non-resonant Au NRs are delivered into mouse liver samples for tracking Au NR diffusion in the samples through continuous OCT scanning for one hour. With resonant Au NRs, the average A-mode scan profiles of OCT scanning at different delay times clearly demonstrate the extension of strong backscattering depth with time. The calculation of speckle variance among successive OCT scanning images, which is related to the local transport speed of Au NRs, leads to the illustrations of downward propagation and spreading of major Au NR motion spot with time.

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