scholarly journals Flavonoid Levels and Antioxidant Capacity of Mulberry Leaves: Effects of Growth Period and Drying Methods

2021 ◽  
Vol 12 ◽  
Author(s):  
Lei Hu ◽  
Cheng Wang ◽  
Xiang Guo ◽  
Dekui Chen ◽  
Wei Zhou ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Freeze Drying ◽  
Growth Period ◽  
Operating Costs ◽  
Drying Methods ◽  
Flavonoid Content ◽  
Air Drying ◽  
Mulberry Leaves ◽  
Mulberry Leaf

In recent years, various mulberry leaf dishes have gradually gained in popularity. The harvesting period of mulberry leaves and the preparation of dried samples are critical for the retention of flavonoid content and activity. In this study, changes in flavonoid levels in mulberry leaves during their growth period (3–6 months), and the effects of four different drying methods [sun drying (SD), air drying (AD), oven drying (OD), and freeze drying (FD)] on flavonoid accumulation and antioxidant capacity were determined. The results showed that mulberry leaves grown for 6 months had higher levels of flavonoids, and different drying methods could significantly affect the flavonoid levels and antioxidant capacity of the leaves. Air drying and FD were the best methods in terms of retaining the antioxidant activity of flavonoids, although AD had lower operating costs than FD in the production process. Therefore, to obtain a high flavonoid content and maximum antioxidant activity, AD is recommended for mulberry leaves.

Improving Nutritional Value of Dried Blueberries (Vaccinium corymbosum L.) Combining Microwave-Vacuum, Hot-Air Drying and Freeze Drying Technologies

2008 ◽  
Vol 4 (5) ◽  
Author(s):  
Esteban I Mejia-Meza ◽  
Jaime A. Yanez ◽  
Neal M. Davies ◽  
Barbara Rasco ◽  
Frank Younce ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Nutritional Value ◽  
Freeze Drying ◽  
Vaccinium Corymbosum ◽  
Drying Methods ◽  
Hot Air Drying ◽  
Total Polyphenols ◽  
Air Drying ◽  
Hot Air ◽  
Freeze Dried

Blueberries (Vaccinium corymbosum L.) were dried combining microwave-vacuum, hot-air drying and freeze drying technologies to retain their nutritional value. Polyphenol retention, total polyphenols, anthocyanins, and antioxidant activity were evaluated in dried blueberries. Glycoside compounds for ellagic acid, quercetin, and kaempferol exhibited a higher retention than phloridzin, and R- and S-naringin in dried blueberries following dehydration. Freeze and HA-MIVAC® dried blueberries had a higher retention of total polyphenols and anthocyanins. Freeze dried blueberries had higher antioxidant activity, followed by the combination of HA-MIVAC®, MIVAC® and HA drying methods. FD, HA-MIVAC® and MIVAC® treated blueberries had a higher retention of individual polyphenols than HA treated blueberries, indicating that the nutritional properties of berries may be retained to a greater extent when these processes are employed.

scholarly journals Supercritical CO2 Extraction of Phytocompounds from Olive Pomace Subjected to Different Drying Methods

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 598
Author(s):  
Graziana Difonzo ◽  
Antonella Aresta ◽  
Pietro Cotugno ◽  
Roberta Ragni ◽  
Giacomo Squeo ◽  
...  
Keyword(s):  
Olive Oil ◽  
Freeze Drying ◽  
Oil Production ◽  
Production Costs ◽  
Drying Methods ◽  
Olive Pomace ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Pharmaceutical Industries

Olive pomace is a semisolid by-product of olive oil production and represents a valuable source of functional phytocompounds. The valorization of agro-food chain by-products represents a key factor in reducing production costs, providing benefits related to their reuse. On this ground, we herein investigate extraction methods with supercritical carbon dioxide (SC-CO2) of functional phytocompounds from olive pomace samples subjected to two different drying methods, i.e., freeze drying and hot-air drying. Olive pomace was produced using the two most common industrial olive oil production processes, one based on the two-phase (2P) decanter and one based on the three-phase (3P) decanter. Our results show that freeze drying more efficiently preserves phytocompounds such as α-tocopherol, carotenoids, chlorophylls, and polyphenols, whereas hot-air drying does not compromise the β-sitosterol content and the extraction of squalene is not dependent on the drying method used. Moreover, higher amounts of α-tocopherol and polyphenols were extracted from 2P olive pomace, while β-sitosterol, chlorophylls, and carotenoids were more concentrated in 3P olive pomace. Finally, tocopherol and pigment/polyphenol fractions exerted antioxidant activity in vitro and in accelerated oxidative conditions. These results highlight the potential of olive pomace to be upcycled by extracting from it, with green methods, functional phytocompounds for reuse in food and pharmaceutical industries.

scholarly journals Effect of Processing on Antioxidant Activity, Total Phenols, and Total Flavonoids of Pigmented Heirloom Beans

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Lisa Garretson ◽  
Catrin Tyl ◽  
Alessandra Marti
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Flavonoid Content ◽  
Processing Step ◽  
Cooking Times ◽  
Dpph Radical Scavenging

While extensive research has been performed on the composition and cooking quality of commodity beans, relatively little is known about pigmented heirloom varieties and the effects of processing on their antioxidant capacity. The aim of this study was to evaluate the effect of soaking and cooking on antioxidants in four heirloom bean varieties compared to Pinto. Water absorption kinetics, soaking and cooking time, DPPH radical scavenging activity, and total phenolic and total flavonoid content were determined in raw, soaked, and cooked samples. Heirlooms required less time to hydrate compared to Pinto, whereas cooking times were similar. The effect of soaking on antioxidant capacity and flavonoids was minimal compared to cooking, which led to losses of up to 57%. Each pigmented heirloom bean had specific characteristics, and three of them had equal or higher amounts of antioxidants or antioxidant activity than Pinto at every processing step. Among heirlooms, Koronis Purple and Jacob’s Cattle had the highest antioxidant activity and Jacob’s Cattle and Tiger’s Eye the highest amount of flavonoids, even after cooking.

scholarly journals Effect of drying methods on properties of green curry powder

2018 ◽  
Vol 192 ◽  
pp. 03023
Author(s):  
Natthacha Chaloeichitratham ◽  
Pornkanya Mawilai ◽  
Thadchapong Pongsuttiyakorn ◽  
Pimpen Pornchalermpong
Keyword(s):  
Moisture Content ◽  
Bulk Density ◽  
Water Activity ◽  
Freeze Drying ◽  
Total Phenolic ◽  
Drying Methods ◽  
Hot Air Drying ◽  
Air Drying ◽  
Drying Temperature ◽  
Hot Air

In this study, the effects of two drying methods: hot-air and freeze drying for Thai green curry paste in a terms of drying time and qualities have been investigated. The hot-air drying was carried out in tray dryer at temperature of 50, 60 and 70 °C. The freeze drying was carried out in freeze dryer at freezing temperature of -20°C, primary drying temperature of -10°C and secondary drying temperature of 50°C. Moisture content, water activity, colour, bulk density, and total phenolic content (TPC) were determined in samples. Freeze dried sample had significantly (p<0.05) lower moisture content, water activity, bulk density, total colour difference and browning index than hot air dried samples. For antioxidant activity, the results showed hot-air drying at 70°C effected highest TPC similar to freeze drying.

Effect of Dehydration Methods on Mechanical Strength of Nanohydroxyapatite/Collagen Composites

2007 ◽  
Vol 330-332 ◽  
pp. 349-352
Author(s):  
Xiao Yan Lin ◽  
Xu Dong Li ◽  
Xing Dong Zhang
Keyword(s):  
Mechanical Properties ◽  
Binding Energy ◽  
Freeze Drying ◽  
Bending Strength ◽  
Bond Formation ◽  
In Situ Synthesis ◽  
Drying Methods ◽  
Key Factors ◽  
Air Drying

Hydroxyapatite/collagen composites were prepared in-situ synthesis. The composites were finally achieved by dehydration including air-drying and freeze-drying methods. FTIR, XPS and DSC were employed to investigate the composites dehydrated by two methods. The air-dried composites had better mechanical properties than those of the composites dried by freeze drying. Air-drying of the composite induced more bond formation and crosslink between collagen fibers and HA crystals compared with freeze-drying of the composite, as indicated by the shifting of amide A and I bands to the lower wavenumber and by the changes in the binding energy of O1s, Ca2p, and P2p, leading to the increase of the peak temperature of the composites. Collagen crosslink and bond formation in the air-dried composites were key factors to increase the bending strength of the composites. The results of this study confirm that in situ synthesis and air-dry method are effective ways to obtain nanoHA/COL composites with high mechanical properties.

scholarly journals The Effect of Different Extraction Protocols on Brassica oleracea var. acephala Antioxidant Activity, Bioactive Compounds, and Sugar Profile

Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1792
Author(s):  
Nikola Major ◽  
Bernard Prekalj ◽  
Josipa Perković ◽  
Dean Ban ◽  
Zoran Užila ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Freeze Drying ◽  
High Energy ◽  
Total Phenolic ◽  
Glucosinolate Content ◽  
Aqueous Methanol ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Sugar Profile

The extraction of glucosinolates in boiling aqueous methanol from freeze dried leaf tissues is the most common method for myrosinase inactivation but can be hazardous because of methanol toxicity. Although freeze drying is the best dehydration method in terms of nutritional quality preservation, the main drawbacks are a limited sample quantity that can be processed simultaneously, a long processing time, and high energy consumption. Therefore, the aim of this study is to evaluate the effects of applying high temperature for myrosinase inactivation via hot air drying prior to the extraction step, as well as the effects of cold aqueous methanol extraction on total antioxidant activity, total glucosinolates, total phenolic content, and sugar profile in 36 landraces of kale. The results from our study indicate that cold aqueous methanol can be used instead of boiling aqueous methanol with no adverse effects on total glucosinolate content. Our results also show that hot air drying, compared to freeze drying, followed by cold extraction has an adverse effect on antioxidant activity measured by DPPH radical scavenging, total glucosinolate content, as well as on the content of all investigated sugars.

scholarly journals Effects of Different Drying Methods on the Characterization, Dissolution Rate and Antioxidant Activity of Ursolic Acid-Loaded Chitosan Nanoparticles

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2470
Author(s):  
Lujie Zhao ◽  
Xu Duan ◽  
Weiwei Cao ◽  
Xing Ren ◽  
Guangyue Ren ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Particle Size ◽  
Ursolic Acid ◽  
Freeze Drying ◽  
Water Solubility ◽  
Drug Loading ◽  
Chitosan Nanoparticles ◽  
Simulated Gastric Fluid ◽  
Drying Methods ◽  
Drying Time

To improve the water solubility of ursolic acid (UA), UA-loaded chitosan nanoparticles were firstly prepared by the ionotropic gelation method and dried by freeze drying (FD), microwave freeze drying (MFD) and spray drying (SD). The characterization of UA-loaded chitosan nanoparticles was performed with particle size, drug loading (DL), scanning electron microscope (SEM), fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), dissolution studies and antioxidant activity. The results demonstrated that UA was successfully encapsulated into chitosan nanoparticles using sodium tripolyphosphate (TPP) as a cross-linker, with a 79% encapsulation efficiency. The spray-dried, UA-loaded chitosan nanoparticles had the lowest drug loading (11.8%) and the highest particle size (496.9 ± 11.20 nm). The particle size of UA-loaded chitosan nanoparticles dried by MFD and FD was lower, at 240.8 ± 12.10 nm and 184.4 ± 10.62 nm, respectively, and their antioxidant activity was higher than those nanoparticles dried by SD. Moreover, the drying time and energy consumption of UA-loaded chitosan nanoparticles dried by MFD and SD were lower than that of FD. The dissolution rates of UA-loaded chitosan nanoparticles prepared by FD and MFD were 60.6% and 57.1%, respectively, in a simulated gastric fluid, which was a greater value than SD (55.9%). Therefore, the UA-loaded chitosan nanoparticles encapsulation method, combined with MFD technology, showed a promising potential to improve the water solubility of UA.

Ultrastructure of Epicuticular Wax in Canola

1989 ◽  
Vol 44 (7-8) ◽  
pp. 705-711 ◽  
Author(s):  
K. L. Conn ◽  
J. P. Tewari
Keyword(s):  
Freeze Drying ◽  
Brassica Campestris ◽  
Amorphous Layer ◽  
Epicuticular Wax ◽  
Drying Methods ◽  
Specimen Preparation ◽  
Drying Method ◽  
Air Drying ◽  
Species Specific ◽  
Wax Crystals

Ultrastructure of the epicuticular wax of four commercially grown Canadian cultivars of canola (Brassica campestris cvs. Tobin and Candle, B. napus cvs. Altex and Westar) was investigated. Freeze-drying and air-drying methods of specimen preparation for scanning electron microscopy were compared. The freeze-drying method resulted in disruption and possible washing away of wax crystals, whereas there was no visible damage with the air-drying method. The freeze-drying method provided evidence for an amorphous layer of wax beneath the wax crystals. Ultrastructure of wax in the four cultivars was generally similar. All cultivars had an evenly distributed layer of wax crystals superimposed on an amorphous layer of wax. Some trends such as density of wax on leaves and siliques appeared to be species-specific, whereas density of wax on stems did not. There appeared to be at least three types of wax crystals present. These included plate-like, filamentous, and rod-like crystals. The rods were present singly or in blocks.

Research on Digestibility of the Mulberry Leaf from the Kokuso 21 Variety in Relation to the Dynamics of the Chemical Content

2018 ◽  
Vol 69 (2) ◽  
pp. 439-444
Author(s):  
Marius Gheorghe Dolis ◽  
Paul Corneliu Boisteanu ◽  
Marius Giorgi Usturoi ◽  
Daniel Simeanu ◽  
Dan Bodescu ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Larval Growth ◽  
Growth Period ◽  
Point Of View ◽  
Silkworm Larvae ◽  
Mulberry Leaves ◽  
Mulberry Leaf ◽  
A Value ◽  
Chemical Content ◽  
Chemical Determination

During the growth of silkworm larvae study, also was done a research which aimed to determine the chemical composition and the digestibility of mulberry leaves from a Japanese variety, Kokuso 21. The results showed that advancing in the vegetation stage at the same time with different periods of the silkworm larvae�s growth, the mulberry leaves experience an aging process being noticed through its quality decreasing from chemical composition point of view. Accordingly, with this, to the majority of nutrients from mulberry leaves, except the crude fiber was noticed a continuous digestibility decreasing throughout larval growth period So, for example, digestibility of crude protein decreased gradually throughout the studied period, with 27.11%, respectively from 84.42% at the first chemical determination to 61.53% at the last one. The nutrients digestibility from the leaves registered in average a value of 55.87%.

Sign in / Sign up

Export Citation Format

Share Document