Enhancing the Properties of Polyvinyl Alcohol Films by Blending with Corn Stover-Derived Cellulose Nanocrystals and Beeswax.

Coating is a technique to surround a target substance with a thin layer to obtain desirable properties. Polyvinyl alcohols (PVAs) are biodegradable plastics and have shown good applicability as a coating or film material. Cellulose nanocrystals are a promising green nanomaterial that has been shown to enhance the properties of PVA after blending. However, these PVA/CNC films have concerns in a moist environment due to high hydrophilicity. To overcome this issue, the current study incorporated beeswax into PVA/CNC films and investigated the effect of CNC and beeswax on the properties of the coatings and films. Results showed that the addition of corn stover-derived CNCs to PVA films increased tensile strength (from 11 to 25 MPa) and Young's modulus (from 32 to 173 MPa) and reduced water vapor transmission rate (from 25 to 20 g h-1 m-2). Beeswax added to PVA/CNC films further improved water vapor barrier properties (from 20 to 9 g h-1 m-2) and maintained Young's modulus (from 173 to 160 MPa), though it caused a reduction in the tensile strength (from 25 to 11 MPa) of the films. This information can help to select materials for blending with PVAs by obtaining the desirable endmost properties depending on applications.

Production of Prunin and Naringenin by Using Naringinase from Aspergillus oryzae NYO-2 and Their Neuroprotective Properties and Debitterization.

Naringin is a flavanone glycoside in citrus fruits that has various biological functions. However, its bitterness affects the quality, economic value, and consumer acceptability of citrus products. Deglycosylation of naringin using naringinase decreases its bitterness and enhances its functional properties. In this study, eight microbial strains with naringinase activity were isolated from 33 yuzu-based fermented foods. Among them, naringinase from Aspergillus oryzae NYO-2, having the highest activity, was used to produce prunin and naringenin. Under optimal conditions, 19 mM naringin was converted to 14.06 mM prunin and 1.97 mM naringenin. The bitterness of prunin and naringenin was significantly decreased compared to naringin using the human bitter taste receptor TAS2R39. The neuroprotective effects of prunin and naringenin on human neuroblastoma SH-SY5Y cells treated with scopolamine were greater than that of naringin. These findings can widen the potential applications of deglycosylation of naringin to improve sensory and functional properties.

Physical and emulsion stabilizing properties of maltodextrin fatty acid polymers produced by lipase-catalyzed reactions in ethanol.

Maltodextrin (MD) fatty acid esters (MFAs) have amphiphilic properties and the enzymatic synthesis of these molecules has gained growing interest. Here, MFAs were synthesized in a food-grade ethanol system and the properties of the products were analyzed. A total of 6 different MFAs were produced with 2 different MD sources and 3 combinations of fatty acids (lauric, palmitic, and both) with yields ranging from 72.7 to 83.4%. With an increase in fatty acid carbon length, degree of substitution (0.026 to 0.016) and solubility (100.9% to 93.1%) were significantly decreased. The stability of emulsions formulated with MFAs was investigated and all emulsions formulated were stable except those containing the lowest concentration of MFAs esterified with palmitate. Notably, MD esterified with laurate showed an enhanced emulsion stabilizing ability as compared to commercial emulsifiers. In conclusion, the emulsion stabilizing ability of MFAs may have applications in the food industry.

Composition and biochemical properties of l-carnitine fortified Makgeolli brewed by using fermented buckwheat.

Makgeolli is a traditional Korean alcoholic rice beverage. It is brewed of ingredients containing starch, Nuruk, and water. In order to improve the quality and functionality of Makgeolli, the Rhizopus oligosporus fermented buckwheat containing 18.7 mg/kg of l-carnitine were utilized to brew l-carnitine fortified Makgeolli with rice. Makgeolli was prepared in two-stage fermentation method and total rutin and quercetin in each fermented buckwheat Makgeolli were increased 1.8-fold greater than buckwheat Makgeolli. DPPH antioxidant activity was enhanced in fermented buckwheat Makgeolli than buckwheat Makgeolli (21.9%-65.7%). The amounts of l-carnitine in rice Makgeolli, buckwheat Makgeolli, and fermented buckwheat Makgeolli were 0.9, 0.8-1.0, and 1.0-1.9 mg/L, respectively. The fermented buckwheat Makgeolli not only promoted health benefit by increasing l-carnitine and flavonols, but also made effective alcohol production (2.8%-8.4%) compared to common buckwheat Makgeolli, indicating the potential industrial application with health benefits.

Characterization of quinoa (Chenopodium quinoa) fermented by Rhizopus oligosporus and its bioactive properties.

Quinoa is a pseudocereal that contains high quality protein, minerals, vitamins, polyphenols, and phytosterols. In this study, quinoa was fermented by Rhizopus oligosporus (R. oligosporus) up to 5 days and the functional compounds (L-carnitine, GABA, vanillic acid and gallic acid) were analyzed by LC/MS. The amounts of L-carnitine and GABA were 0.13 mg/kg and 540 mg/kg for nonfermented quinoa (NF), 3.15 mg/kg and 1040 mg/kg for fermented quinoa at 3 days (3F), and 1.54 mg/kg and 810 mg/kg for fermented quinoa at 5 days (5F). The vanillic acid and gallic acid were 1.3 and 0.1 mg/kg for NF, 1.55 and 2.37 mg/kg for 3F, and 1.83 and 0.84 mg/kg for 5F, respectively. Total phenolic contents and total flavonoids contents were 41 mg gallic acid (GAE)/kg and 13 mg quercetin equivalent (QE)/kg for NF, 74 mg GAE/kg and 16 mg QE/kg for 3F, and 80 mg GAE/kg and 19 mg QE/kg for 5F, respectively. Antioxidant activity (SC50) was 3.6 mg/mL for NF, 3.4 mg/mL for 3F, and 2.3 mg/mL for 5F. Nitric oxide production on RAW264.7 macrophages of fermented quinoa revealed 29% and 56% inhibition of nitric oxide production for NF and 5F, respectively. Therefore, fermented quinoa can be used as a healthy and valuable food product.

The use of fermented buckwheat to produce L-carnitine enriched oyster mushroom.

L-Carnitine is an essential compound that shuttles long chain fatty acids into mitochondria. The objective of this study was to produce L-carnitine enriched oyster mushroom (Pleurotus ostreatus) using common buckwheat fermented by Rhizopus oligosporus. Mushroom grown on common buckwheat medium contained 9.9-23.9% higher L-carnitine (186.3 mg/kg) than those grown on basal medium without any buckwheat addition. Those grown on fermented common buckwheat medium contained the highest L-carnitine content (201.2 mg/kg). Size index and lightness of mushroom pileus (L*) were also the highest (100.7 and 50.6, respectively) for those grown in medium added with fermented common buckwheat (20%, w/w). Antioxidant activities of both mushroom extracts (1.5 mg/mL) showed the same level as 38.7% for mushroom grown in media added with common buckwheat or fermented common buckwheat. At the treatment concentration of 300 µg/mL, viabilities of murine macrophage cell line Raw 264.7 cells treated with ethanol extract of oyster mushroom grown on buckwheat medium ranged from 58.9 to 67.8%. The oyster mushroom grown on buckwheat and fermented buckwheat medium can be used as one of the substitutes for meat based diets.

The effect of fermented buckwheat on producing l-carnitine- and γ-aminobutyric acid (GABA)-enriched designer eggs.

BACKGROUND: The potential of fermented buckwheat as a feed additive was studied to increase l-carnitine and γ-aminobutyric acid (GABA) in designer eggs. Buckwheat contains high levels of lysine, methionine and glutamate, which are precursors for the synthesis of l-carnitine and GABA. Rhizopus oligosporus was used for the fermentation of buckwheat to produce l-carnitine and GABA that exert positive effects such as enhanced metabolism, antioxidant activities, immunity and blood pressure control. RESULTS: A novel analytical method for simultaneously detecting l-carnitine and GABA was developed using liquid chromatography/mass spectrometry (LC/MS) and LC/MS/MS. The fermented buckwheat extract contained 4 and 34 times more l-carnitine and GABA respectively compared with normal buckwheat. Compared with the control, the fermented buckwheat extract-fed group showed enriched l-carnitine (13.6%) and GABA (8.4%) in the yolk, though only l-carnitine was significantly different (P < 0.05). Egg production (9.4%), albumen weight (2.1%) and shell weight (5.8%) were significantly increased (P < 0.05). There was no significant difference in yolk weight, and total cholesterol (1.9%) and triglyceride (4.9%) in the yolk were lowered (P < 0.05). CONCLUSION: Fermented buckwheat as a feed additive has the potential to produce l-carnitine- and GABA-enriched designer eggs with enhanced nutrition and homeostasis. These designer eggs pose significant potential to be utilized in superfood production and supplement industries. © 2016 Society of Chemical Industry.

Functional Properties of Novel Epigallocatechin Gallate Glucosides Synthesized by Using Dextransucrase from Leuconostoc mesenteroides B-1299CB4.

Epigallocatechin gallate (EGCG) is the most abundant catechin found in the leaves of green tea, Camellia sinensis. In this study, novel epigallocatechin gallate-glucocides (EGCG-Gs) were synthesized by using dextransucrase from Leuconostoc mesenteroides B-1299CB4. Response surface methodology was adopted to optimize the conversion of EGCG to EGCG-Gs, resulting in a 91.43% conversion rate of EGCG. Each EGCG-G was purified using a C18 column. Of nine EGCG-Gs identified by nuclear magnetic resonance analysis, five EGCG-Gs (2 and 4-7) were novel compounds with yields of 2.2-22.6%. The water solubility of the five novel compounds ranged from 229.7 to 1878.5 mM. The 5'-OH group of EGCG-Gs expressed higher antioxidant activities than the 4'-OH group of EGCG-Gs. Furthermore, glucosylation at 7-OH group of EGCG-Gs was found to be responsible for maintaining tyrosinase inhibitory activity and increasing browning-resistant activities.