scholarly journals Effects of pretreatment and drying temperature on antioxidants and antinutrients of Justicia insularis and Jatropha tanjorensis leaves

2021 ◽  
Vol 46 (3) ◽  
pp. 74-88
Author(s):  
Mfrekemfon Akpan ◽  
Ubong Assian ◽  
Elijah Ikrang

Antioxidants and antinutrient contents of leafy vegetables may be influenced by post-harvest processing. The present study was carried out to assess the effect of pretreatments (P) and drying temperatures (T) on antioxidants and antinutrients of Justicia insularis and Jatropha tanjorensis leaves. Four groups of samples were prepared, namely: fresh sample (FR), UN-blanched and dried sample (UB), sample blanched in hot water and dried (BHW) and sample blanched in salt water and dried (BSW). Drying was conducted at 40 0C, 50 0C and 60 0C using hot air oven. Antioxidants and antinutrients of the samples were determined. The data collected were subjected to a two-way Analysis of Variance (ANOVA) as well as Dunnett t-test at 5% probability level. Based on the results, BHW between 500 C and 600 C increased the antioxidant activity in both vegetables. BHW 60 0C was able to reduce oxalate and phytate contents to reasonable level while BSW50 0C drastically decreased hydrogen cyanide and tannin contents. However, the overall, individualistic, and interactive effects of P and T had significant ( < 0.05) influence on majority of antioxidant activity and antinutrient contents in both vegetables.

Author(s):  
Khvorova L.S. ◽  
Byzov V.A.

The article is devoted to the creation of a carbohydrate product with rosehip extract in the form of sweets (glucose Fudge) with a therapeutic and preventive effect aimed at restoring the body of people exposed to intense physical and mental stress and the effects of damaging environmental factors. As carbohydrates in the recipe, simple carbohydrates (glucose) and complex carbohydrates in the form of starch molasses containing (maltose, tri - Tetra - sugars, dextrins) are used. Glucose in the formulation is the main energy ingredient, sweetener and structure-forming component that gives the product a solid consistency due to crystallization. The medicinal effect of the product is provided by rosehip extract. Numerous published studies have established its vitamin, immunostimulating and antioxidant activity, inhibition of uric acid formation and obesity, which are associated with flavonoids, other phenolic compounds, and vitamins. The list of medicinal properties of rosehip extract shows the feasibility of using it in additional nutrition of people in order to prevent diseases. For the formulation of our sweets, the extraction of crushed rosehip fruits was carried out three times with hot water at a temperature of 65-700C, followed by concentration of the extract under vacuum to 25-30% SV. The resulting extract-concentrate was introduced into the formulation in a dosage of 5.5% SV per 100 g of SV glucose Fudge, which provided the necessary dosage for the product when used from 3 (for children) to 10 sweets a day (for adults) for the prevention of colds.


HortScience ◽  
1994 ◽  
Vol 29 (4) ◽  
pp. 249a-249
Author(s):  
Eric A. Lavoie ◽  
Damien de Halleux ◽  
André Gosselin ◽  
Jean-Claude Dufour

The main objective of this research was to produce a simulated model that permitted the evaluation of operating costs of commercial greenhouse tomato growers with respect to heating methods (hot air, hot water, radiant and heat pumps) and the use of artificial lighting for 1991 and 1992. This research showed that the main factors that negatively influence profitability were energy consumption during cold periods and the price of tomatoes during the summer season. The conventional hot water system consumed less energy than the heat pump system and produced marketable fruit yields similar to those from the heat pump system. The hot water system was generally more profitable in regards to energy consumption and productivity. Moreover, investment costs were less; therefore, this system gives best overall financial savings. As for radiant and hot air systems, their overall financial status falls between that of the hot water system and the heat pump. The radiant system proved to be more energy efficient that the hot air system, but the latter produced a higher marketable fruit yield over the 2-year study.


Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 641
Author(s):  
Hee Young Kim ◽  
Meran Keshawa Ediriweera ◽  
Kyung-Hwan Boo ◽  
Chang Sook Kim ◽  
Somi Kim Cho

We investigated the effects of cooking (steaming and microwaving) and processing (freeze-drying and hot-air-drying) methods on the antioxidant activity of broccoli florets. 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•), and alkyl• free radical scavenging assays were employed to assess anti-oxidant potentials. The cytoprotective effect against oxidative damage induced by H2O2 was studied using hepatocellular carcinoma (HepG2) cells. Anti-proliferative effects were assessed in MCF-7 and MDA-MB-231 breast cancer cells. L-sulforaphane in broccoli extracts was quantified using high-performance liquid chromatography (HPLC). Steam and microwave treatments caused increases in total polyphenol content (TPC), whereas the total flavonoid content (TFC) decreased following steam treatment. A slight increase in TFC was observed in the microwaved samples. Extracts of all broccoli samples showed almost identical radical scavenging and cytoprotective effects. HPLC demonstrated that steamed (3 min)-freeze-dried (F-S3) and microwaved (2 min)-freeze-dried (F-M2) samples exhibited elevated levels of L-sulforaphane. In addition, the F-S3 and F-M2 extracts displayed strong anti-proliferative effects in MCF-7 cells, which correlated with L-sulforaphane content. As we observed no significant decrease in the antioxidant activity of broccoli florets, the cooking and processing methods and conditions studied here are recommended for broccoli.


Food Research ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 120-126
Author(s):  
N. Wuttisin ◽  
T. Nararatwanchai ◽  
A. Sarikaphuti

Plukenetia volubilis L. leaves were part of the traditional diets in many countries. P. volubilis leaves were used to make tea and sold as local products in Thailand. There is less information on the composition of P. volubilis leaves. Previous study revealed that roasted leaves extract with hot water showed the highest antioxidant activity and the antioxidant property might be due to the presence of flavonoid. The present study was carried out to determine the quercetin content in P. volubilis leaves extract and evaluate the anti-aging potential activities including MMP-2 inhibition activity and telomerase stimulation activity. P. volubilis leaves were roasted in hot air oven and extracted with hot water. The extract was investigated for quercetin content by high-performance liquid chromatography (HPLC). In vitro cytotoxicity, MMP-2 inhibition activity and telomerase stimulation activity were determined for anti-aging properties. The results revealed that P. volubilis leaves contained quercetin 50.50±4.78 mg/g DW. The extract showed no cytotoxicity on human skin fibroblast with cell viability of 96.76-120.83%. It demonstrated the potential of MMP-2 inhibition (8.74±2.84%) activity but lower than ascorbic acid. P. volubilis leave extract did not have telomerase stimulation activity on the human Hela cell line. However, the results from this study have indicated the possibility of anti-aging potential of P. volubilis leaves extract.


2011 ◽  
pp. 279-288 ◽  
Author(s):  
Anita Klaus ◽  
Maja Kozarski ◽  
Miomir Niksic

Ganoderma lucidum (Leyss.:Fr.) Karst is one of the medicinal mushrooms, which possesses enviable antioxidant properties. Objective of this investigation was to evaluate antioxidant activity, reducing power, scavenging abilities on 1.1-diphenyl-2-picrylhydrazyl (DPPH) radicals and chelating effects on ferrous ions of hot water extracts obtained from carpophore and spores of this mushroom. Hot water extract from carpophore (Gl-I) showed high antioxidant activity of 85.7 ? 0.7%, at 10 mg/ml, while antioxidant activity of hot water extract from spores (Gl-Is) was 9.2 ? 0.3% at 10 mg/ml. Reducing power of Gl-I reached a plateau of 3.4 ? 0.1 at 20 mg/ml, and 0.3 ? 0.0 at 20 mg/ml for Gl-Is. At 10 mg/ml, scavenging ability on DPPH radicals of Gl-I increased to 96.8 ? 2.5%, whereas Gl-Is scavenged DPPH radicals by 69.6 ? 2.5% at 10 mg/ml. Gl-I chelated 81.6 ? 3.6 % of ferrous ions at 20 mg/ml, while the chelating effect of Gl-Is was 73.8 ? 1.7%. The antioxidative activities of hot water extracts from carpophore and spores of the mushroom G. lucidum were concentration dependent and increased with an increase in the concentration.


Food Research ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 410-415
Author(s):  
N. Mongkontanawat ◽  
D. Thumrongchote

Schizophyllum commune Fr., a native mushroom of Thailand, has a high nutritional value and is classified as a mushroom with medicinal properties that can neutralize the growth of many cancer cells. This research aimed to study the effect of S. commune strains and the extraction methods on the quantity and properties of β-glucan. The five S. commune Fr. strains used in this research consisted of Chanthaburi, 85-022, 85-023, 85-031, and 85- 043. There were two different β-glucan extraction methods employed: hot water (M1) and hot alkali extraction (M2), which were compared with the control (native-MR). The results indicated that the Chanthaburi strain has the highest β-glucan content 49.20±0.35% (w/w), and high potential antioxidant activity (79.14±0.77 DPPH% and 50.92±0.48 ABTS%) (p < 0.05). The extraction methods did not affect the yield of β-glucan, except the antioxidant properties and chemical structure of the extract substance. The extract substance from M2 has significantly the highest potential antioxidant activity (80.22±0.51). A mushroom juice drink in cans was developed using 1-day-old MR and adjusted pH of more than 7, which can increase the antioxidant properties of the product.


Author(s):  
Pranabendu Mitra ◽  
Venkatesh Meda ◽  
Rick Green

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.


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