Raisin Extract Research Articles

Optimization Effect on Green Synthesis of Silver Nanoparticles (AgNPs) Using Dimrit Raisin Extract and Their Antimicrobial Activity

This paper describes the simple and environmentally friendly production of AgNPs using Dimrit raisin, grown in Burdur, extract. To optimize the synthesis of AgNPs, a number of variables, including extract concentration, silver solution concentration, synthesis time, and synthesis temperature, were investigated. AgNPs were obtained after 173 h at 1% extract concentration and 10-1 M silver concentration. The structure of the synthesised AgNPs was investigated by Transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FT-IR). TEM analysis showed that the majority of the AgNPs had a spherical shape, and the average particle size was 30 nm. Antimicrobial activity was seen against Staphylococcus aureus ATTC43300, Enterococcus faecalis ATTC29212, Bacillus subtilis, Listeria monocytogenes, Klebsiella pneumoniae and Gram-negative Salmonella enterocolitis, E. coli 0157:H7 ATTC 43895, and Escherichia coli ATTC 35150.

Biosynthesis of Gold Nanoparticles (AuNPs) with Dimrit Raisin Extract and Their Degradation Activity for Water Contaminants

AuNPs are being conventionally synthesized by traditional methods (physical and/or chemical) with preferred and well-defined morphology, size and shape. On the other hand, it has been reported that these methods involve difficult reaction conditions and/or toxic chemicals. In this study, an easy, cost effective and more environmentally and biological-friendly method was described for the synthesis of gold nanoparticles with Dimrit raisin extract for the first time. The effects of some experimental parameters, such as concentrations of both raisin extracts and Au solutions, synthesis time and synthesis temperature were investigated for the synthesis of AuNPs. The synthesized AuNPs were extensively characterized by UV-Visible spectrometer, Transmission electron microscopy (TEM), X-ray diffraction patterns (XRD) and Fourier transform–infrared spectroscopy (FTIR). TEM results show spherical along with triangular and hexagonal shaped nanoparticles with an average size of 15 nm. Large amounts of toxic dyes are used in the different industrial area and dyes posed a threat for water sources. Therefore, it has become imperative to develop inexpensive and environmentally friendly methods to remove dyes from water. In recent years, degradation using green synthesized nanoparticles has become an efficient method to remove dyes from the water sources. In this study, the catalytic activity of the AuNPs for the degradation of both methylene blue (MB) and methyl orange (MO) dyes were also studied and AuNPs behaved as effective catalysts for both degradations of MB and MO dyes in terms of percentage removal and kinetics. The experiment results showed that AuNPs can be employed as strong candidate in wastewater treatment studies.

Black Raisins Improved Experimentally Induced Iron Deficiency Anemia. Biochemical and Histological Evidence

Iron deficiency anemia is a challenging clinical problem with a profound impact on general health. Administration of iron-containing preparations were reported to be associated with many side effects. The current study aimed to evaluate black raisins’ therapeutic role against experimentally induced iron deficiency anemia in rats. Forty female rats were divided into 4 groups (n=10); control, anemia, anemia + iron, and anemia + raisins. Anemia was induced by bleeding and an iron-deficient diet for 4 weeks. Anemic rats were treated with ferric sulfate (200 mg/kg) or raisin extract (375 mg/kg) daily for 12 weeks. Complete blood count (CBC), blood films, body weight, splenic weight, and index were assessed. The spleens were processed and stained by hematoxylin and eosin (H & E) and immunohistochemically stained for CD3+ and CD68. Raisins contain a considerable amount of iron, vitamin B, phenolics, and flavonoid antioxidants. In raisins treated rats, CBC parameters displayed a significant increase compared to the anemic rats. Most of the RBCs in blood films showed normal shape, size, and central pallor. The spleen of raisins and iron-treated rats showed a marked increase in the area of white pulp. Their spleens also showed a significant increase in the CD3+ PALS area compared to anemic rats. Iron and raisins significantly decreased splenic CD68 macrophages. Consumption of black raisins could be considered an excellent natural source for flavonoids and iron to be used as an adjuvant supplement to iron for anemic patients with increased splenic T lymphocytes.

Effect of feeding by raisin extract on some biological aspects of honey bee Apis mellifera L.

Results showed that the use of raisin extract has a highly significant effect on the activity of bees, Apis mellifera and their ability to produce honey, brood and the quantities of collected pollen. The treatment of raisin extract 30% with a mixture of sugar, honey, soybean, vitamin B-plex, tetracycline and water has outperformed the other of the treatments with honey production area, brood area produced and pollen area during of all periods of study. The area of honey during the three consecutive periods was 5188, 7800, 4040 inch2 and the area of the brood produced during the same periods was 4235, 10780 and 5487 inch2, while the area of pollen for the same periods also amounted to 1715, 7730, 2370 inch2, respectively. While the treatment of only natural feeding was the lowest treatment of all the terms of honey, brood and pollen with a high significant difference, so this indicates the importance of feeding for bees and the importance of the presence of raisin extract in this feeding especially in the summer and winter to help the bees completing their vital works and thus survival and production of large quantities of brood and other bees production.

Gastronomi ve Moleküler Gastronomi Açısından Üzüm Pekmezi

Molecular gastronomy is a scientific field that contains the food materials, food ingredients, food additives, method of preparation of the food and appreciated by consumers. Grape pekmez, one of the traditional foods subject to our study, is the thick product obtained by reducing the acidity of unfermented fresh or raisin extracts by suitable methods and then thickening under vacuum or in the light in accordance with the technique. Although, today pekmez is generally produced industrially, it is also produced according to local methods partly in rural areas. It is also an important food in terms of nutrition and health by meeting most of the daily requirement of calcium, iron, potassium and magnesium.In this study; it was tried to be explained the changes in chemical and biochemical components which appear positively or negatively in pekmez during production that is molecular gastronomic transformations from raw material to finished product by focusing on the production stages. Thus, the production of pekmez was assessed in the gastronomic and molecular gastronomic directions.

Fenitrothion sensing with reduced graphene oxide decorated fumed silica nanocomposite modified glassy carbon electrode

In this study, a nanocomposite was prepared via reducing graphene oxide on fumed silica (FS) surface to develop a modified electrode for the determination of fenitrothion (FNT). Reduced graphene oxide (RGO) decorated FS (FS@RGO) was used to modify glassy carbon (GC) electrode. The modified electrode decreased the overpotential of FNT (80 mV) and increased prominently the reduction peak current of FNT (9 times). Scanning electron microscopy, energy dispersive X-ray, X-ray diffraction and Raman spectroscopy analyses revealed that the FS@RGO nanocomposite was successfully synthesized. The presence of FS on FS@RGO structure prevented the agglomeration and allowed the homogeneous distribution of the nanocomposite in water, which was a drawback for RGO. Moreover, the presence of FS brings additional functionality to FS@RGO nanocomposite, which increases the adsorption and electron transfer rate of FNT. The GC/FS@RGO electrode showed a linear response in a wide range of FNT concentration (0.005–1.0 μM) and a very low limit of detection (0.00019 μM). The performance of the GC/FS@RGO electrode was evaluated by performing recovery studies in river water, urine, raisin extract, tomato extract and orange extract. Acceptable recovery values between 92.3% and 112.2% were obtained during the analysis of FNT-spiked samples.

Antifungal activity of Lactobacillus gasseri and raisin extract against the growth of Aspergillus parasiticus in yogurt

Antifungal activity of Lactobacillus gasseri and raisin extract against the growth of Aspergillus parasiticus in yogurt

Identification of phenolic compounds, antibacterial and antioxidant activities of raisin extracts.

In this study, antibacterial, antioxidant and phenolic compounds of raisin extracts was evaluated. Different solvent extraction methods were utilized to extract phenolic compounds from raisin. The phenolic compounds of raisin extracts was determined using HPLC and three compounds were found, catechin, quercetin and rutin. The antibacterial activity of the acetonic extract was tested against four bacterial pathogens viz. Staphylococcus aureus, Pseudomonas aeroginosa, Salmonella typhimurium and Escherichia coli using both disk diffusion and minimum inhibitory concentration (MIC) methods. The acetonic extract exhibited the highest activity against Staphylococcus aureus with zone of inhibition of 14mm and the MIC of 25 mg/ml. However, there was a little activity against E. coli and S. typhimurium. The methanolic extract showed good antioxidant activity as indicated by 2,2-diphenyl-1-picrylhydrazyl free radical assay (DPPH). In conclusion, raisin contains potent phenolic compounds and their application might function as promising natural preservative and antimicrobial agents in food industry and also good antioxidant food that helps to minimize the risk of degenerative diseases.

Application of Fourier Transform Infrared (FTIR) Spectroscopy for Rapid Detection of Fumonisin B2 in Raisins.

The aim of this study was to investigate the potential use of FTIR spectroscopy as a rapid screening method to detect fumonisin produced by Aspergillus niger. A. niger spore suspensions isolated from raisins were inoculated in Petri dishes prepared with sultana raisin or black raisin extracts containing agar and malt extract agar (MEA). After 9 days of incubation at 25°C, fumonisin B2 (FB2) production on each agar plate was determined by subjecting the agar plugs to IR spectroscopy. The presence of amino group (at 1636-1639 cm(-1)) was especially indicative of fumonisin production in MEA and the raisin extracts containing agar. The results were confirmed by HPLC analysis of the agar sample extracts after immunoaffinity column cleanup. It was determined that A. niger produced more FB2 in sultana raisins than in MEA, with no FB2 being produced in black raisin extract agar. This study demonstrated that proper sample preparation procedure followed by FTIR analysis is a useful technique for identifying toxigenic molds and their mycotoxin production in agricultural commodities.

Hypoglycemic and Hypolipidemic Effects of Raisin Aqueous Extract “Karkni” in Alloxan-Induced Diabetic Rats

The present study was carried out to investigate the possible antioxidant effects of raisin extract “Karkni” on biochemical parameters in alloxan-induced diabetic rats. Three doses of extract, 125, 250 and 375 mg/kg were orally administered daily to alloxan-diabetic rats for 4 weeks. Alloxan-induced diabetic rats showed significant increases in the levels of blood glucose, triglycerides, cholesterol, low density lipoprotein LDL-cholesterol, creatinine, uric acid, total protein, glycosylated hemoglobin (HbA1c), Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) while high density lipoprotein HDL cholesterol, total hemoglobin and lactate dehydrogenase (LDH) levels were significantly decreased compared to normal rats (P<0.05). The changes of the above parameters to their normal levels after 4 weeks of treatment were observed mainly with the second dose 250 mg/kg. The overall results suggest that the “Karkni” extract possesses potential hypoglycemic and hypolipidemic activity in alloxan-induced diabetic rats.

Application of Raisin Extracts as Preservatives in Liquid Bread and Bread Systems

Interest in natural ingredients with multifunctions in food has led to the investigation of the antimicrobial activity of raisins, a traditional baking ingredient. Water and 60% ethanol extracts, and raisin juice concentrate (RJC, a commercial food ingredient) were assessed for their ability to inhibit the growth of ropy-bread-causing Bacillus species. The ability of these additives and raisin paste were tested for antifungal activity in liquid bread model system and bread. In the liquid bread model, concentrations as low as 20 and 36 mg crude extract or RJC per gram media significantly (P < 0.05) reduced the populations of B. licheniformis and B. subtilis, respectively. A significant reduction in the population of Aspergillus flavus and Penicillium chrysogenum was achieved at 80 and 470 mg crude extract per gram media, respectively. Bread formulas containing 7.5% of a water extract (equivalent to 70 mg extract per gram dough) or RJC (70 mg/g dough) produced bread that had equivalent mold-free shelf life. The mean mold-free shelf life of the bread containing 7.5% water extract was 18.1 +/- 3.3 d at room temperature while the negative control was mold free for 9.4 +/- 2.4 d. The antifungal efficacy of the extracts in bread was equivalent to 0.24% calcium propionate in 21 d of storage. Doubling the concentration of the extract did not improve the mold-retarding property in bread. The bread containing raisin paste, the percentage of which in dough was equivalent to 15% raisin extract, exhibited a stronger antifungal activity than did the extracts in bread.

Sourdough 대체가 호밀-밀 혼합빵의 품질 특성에 미치는 영향

Rye-wheat mixed bread samples made with substitutions of 20, 40, 60 and 80% sourdough, and control made with the addition of naturally fermented raisin extract, were examined for quality characteristics such as pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, water activity, color, texture, external and internal surface appearance, and sensory qualities, in order to determine the optimal ratio of sourdough in the formulation. As the incubation time of sourdough increased, pH decreased, while total titratable acidity increased. The pH of rye-wheat mixed doughs decreased with increasing sourdough content, but total titratable acidity increased. The rye-wheat mixed breads prepared with substitutions of sourdough had higher pH and lower total titratable acidity than the control group. Fermentation power of dough expansion of rye-wheat mixed doughs increased with increasing incubation time. Specific volume was maximum on the 20% substitution sourdough. Baking loss was inferior with the 80% substitution sourdough. Water activity and lightness was minimum on the control group. The higher amounts of sourdough showed the higher tendency of lightness, redness and yellowness. In the texture characteristics, hardness, gumminess, and chewiness was minimum on the control group and tended to increase with higher substitution of sourdough. Substitution of sourdough showed decrease adhesiveness. Fracturability, cohesiveness, and resilience of all rye-wheat mixed breads were not significantly different. Springiness was maximum on the 20% substitution sourdough and minimum on the 40%. A side of loaf of rye-wheat mixed breads, except for 20%, had a poor break and shred. In sensory evaluation, as substitution amount of sourdough increased, the scores of color and consistency of crumb, uniformity of crumb pore, gumminess, and overall acceptability decreased; while the density of crumb pore, springiness of crumb, aroma of rye flour, sourness, and bitterness showed the reverse effect; the 20, 40, and 60% sourdough samples obtained fairly good scores. In conclusion, these results indicated that 20～60% of sourdough could be very useful as a substitute for baker's yeast in developing rye-wheat mixed bread.

Composition and antioxidant activity of raisin extracts obtained from various solvents

Experiments were conducted to determine if the contents of phenolics and browning reaction products and antioxidant activity of raisin extracts were closely dependent on the extraction solvent. Enhanced extraction yields were obtained from solvent containing higher water concentrations. However, total phenolic content (TPC) was highest for extracts obtained from solvent to water ratios of 60:40 (v/v), whereby the extract obtained from ethanol:water (60:40, v/v) had the highest TPC of 375mg gallic acid equivalents (GAE)/100g extract. HMF content was highest in extracts obtained from 60% solvent, regardless of solvent type. The extract obtained from 60% methanol had the highest HMF content at 199μg/g extract. Although the 60% solvents provided extract with high antioxidant components, the antioxidant activity of raisin extracts obtained from 80:20 (v/v) solvent/water was significantly higher than other raisin extracts obtained from different solvent concentrations. Phenolic acids, HMF, and low-molecular-weight flavonoids were responsible for the antioxidant activity, but not the high-molecular-weight flavonoids.

Antioxidant Activity of Raisin Extracts in Bulk Oil, Oil in Water Emulsion, and Sunflower Butter Model Systems

AbstractThe antioxidant activities of the raisin extract (RE) in stripped corn oil, stripped corn oil emulsions, and sunflower butter stored at 60 °C for up to 15 days was evaluated. Peroxide values and hexanal content were measured on a half day, 2 or 3 day basis for the emulsion, sunflower butter, and bulk oil, respectively. The RE had the best antioxidant activity in the bulk oil system. Statistical contrasts indicated the oxidation of bulk corn oil treated with RE was significantly (p &lt; 0.001 and p = 0.044) lower than bulk oil and bulk oil treated with tertiary‐butylhydroquinone (TBHQ), respectively. No differences (p = 0.15) in hexanal concentrations were observed in stored bulk oils treated with RE and TBHQ. However, both these materials inhibited hexanal formation better (p &lt; 0.001) when compared to the control corn oil. In contrast, 200 μg/g TBHQ had better (p = 0.0004) antioxidant activity than 3,000 μg/g RE in the oil in water(o/w) emulsion. No significant differences (p = 0.1637) in hexanal formation were observed in the emulsions treated with RE and TBHQ. However, the data indicated that the RE treated emulsion did undergo more secondary oxidation than the emulsion treated with TBHQ beyond 110 h. The 3,000 μg/g RE had antioxidant activity in sunflower butter, but was less effective than the 200 μg/g TBHQ and a lower RE concentration (200 μg/g). The observations supported the hypothesis that RE has antioxidant activity in the multiple model systems.

Identification and Occurrence of β-Carboline Alkaloids in Raisins and Inhibition of Monoamine Oxidase (MAO)

Monoamine oxidase (MAO) is a mitochondrial enzyme involved in the oxidative catabolism of neurotransmitters and xenobiotic amines, including vasopressor and neurotoxic amines, and a current target for antidepressant and neuroprotective drugs. Raisin extracts and homogenates exhibited reversible in vitro inhibition of MAO isozymes, particularly MAO-A, suggesting the presence of MAO-inhibiting substances. Chromatographic and spectrometric studies showed the occurrence of aromatic beta-carboline alkaloids in raisins, and norharman and harman were identified as the key contributors to MAO inhibition. On average, harman ranged from 6 to 644 ng/g and norharman from 2 to 120 ng/g. Several technological variables appeared to determine the presence of these compounds in raisins. Dark-brown raisins (i.e., sun-dried) contained much higher levels than golden raisins. Tetrahydro-beta-carboline-3-carboxylic acid compounds that are direct precursors of aromatic beta-carbolines were also identified in raisins and appeared in a higher amount, reaching up to 50 microg/g. beta-Carbolines were isolated from raisins and acted as good competitive inhibitors of MAO-A (harman) and MAO-B (norharman) isozymes. These results suggest that beta-carboline alkaloids and perhaps raisins containing a high level of beta-carbolines might exhibit potential activity as MAO inhibitors. The results also show that some raisins can be a source of dietary exposure to bioactive beta-carbolines.

Kefir-yeast technology: Industrial scale-up of alcoholic fermentation of whey, promoted by raisin extracts, using kefir-yeast granular biomass

Industrial scale-up of whey fermentation, promoted by raisin extracts, using free kefir-yeast cells is reported. The fermented whey would be exploited as raw material to produce kefir-like whey-based drinks, potable and fuel alcohol, as well as kefir-yeast biomass for use as baker's yeast. The scale-up process involved the development of a technology transfer scheme from lab-scale experiments to a successive series of increased capacity bioreactors (100, 3000 and 11,000 L). The development of this technology was supported by the six-fold promotion of whey fermentation by the addition of 1% black raisin extracts (optimum concentration found in this investigation), as well as by the formation of kefir-yeast in the form of easily precipitated granular biomass that led to the avoidance of centrifugal separators, which are equipment of high cost. A cost analysis showed a big reduction of the production cost of the aforementioned products in comparison with the market prices, attributed to the negligible cost of raw materials (whey) and the granular biomass formation.

Use of Saccharomyces cerevisiae cells immobilized on orange peel as biocatalyst for alcoholic fermentation

A biocatalyst was prepared by immobilizing a commercial Saccharomyces cerevisiae strain (baker’s yeast) on orange peel pieces for use in alcoholic fermentation and for fermented food applications. Cell immobilization was shown by electron microscopy and by the efficiency of the immobilized biocatalyst for alcoholic fermentation of various carbohydrate substrates (glucose, molasses, raisin extracts) and at various temperatures (30–15 °C). Fermentation times in all cases were low (5–15 h) and ethanol productivities were high (av. 150.6 g/ld) showing good operational stability of the biocatalyst and suitability for commercial applications. Reasonable amounts of volatile by-products were produced at all the temperatures studied, revealing potential application of the proposed biocatalyst in fermented food applications, to improve productivities and quality.

Effect of Dried Raisins and Apricots Extract on the Growth of Bifidobacteria in Cows and Goats Milk

The study confirms the growth of Bifidobacteria (B. infantis) in milk mixed with dried fruits (apricots and raisins) extract with no significant difference at (p<0.05) regardless of the milk type and the fruit extract concentration. The sensory evaluation of bifidus milk extracts fermented by B. infantis prepared from cow's and goat's milk with dried raisin and apricot extract each at 10% (v/v) concentration, showed a significant acceptability at (P< 0.05) for both cow's and goat's milk with apricot extract against a lower acceptability obtained for milks with raisin extract with a significant differences at (P< 0.05).

Development of a novel whey beverage by fermentation with kefir granules. Effect of various treatments.

The development of a novel whey-based beverage with acceptable organoleptic properties is reported, where various treatments were studied. Kefir yeast immobilized on delignified cellulosic materials (DCM) or gluten pellets proved to accelerate whey fermentation significantly, with the latter support being not so preferable. Kefir granules seemed to achieve similar fermentation times as DCM. The final pH of the product is suggested to be 4.1 since the profile of the volatile byproducts was higher than other pH values tested. The addition of fructose seemed to be beneficial on the volatile content of the product, although its acceptability as determined by a preference panel was similar to that of the control. Finally, black raisin extract appeared to promote fermentation without any positive effect on the preference of the evaluators.

Influence of polysaccharide addition on stability of a cheese whey kefir-milk mixture

A kefir-type drink was prepared by fermentation with kefir granules of cheese whey containing fructose and black raisin extract. Milk (20%) was then added to improve its rheological and sensory properties and in order to prevent casein coagulation and sedimentation in the acid environment of the mixture, a number of polysaccharides were evaluated as stabilizers. Xanthan appears to be more effective at relatively low concentration levels (0.2%) compared to guar gum while high methoxyl pectin, a well-known acid milk drink stabilizer was less effective in this respect even at concentrations as high as 1%. Particle size and rheology measurements pointed out to the importance of the weak gel properties of xanthan solution in stabilizing the system against ‘wheying off’ while other stabilization mechanisms such as particle network formation as a result of depletion flocculation in the case of guar gum or pectin adsorption at the casein particle surface resulting in steric stabilization appear to be less dominant.