Improvement of the drying quality of blueberries by catalytic infrared blanching combined with ultrasound pretreatment.

This paper investigated the effect of catalytic infrared blanching combined with ultrasound pretreatment on quality and waxy structure of blueberries. Different blueberry samples were prepared, including control (untreated) and samples treated by hot water blanching (HB), catalytic infrared blanching (CIB), ultrasound-catalytic infrared blanching (US-CIB), and catalytic infrared blanching-ultrasound (CIB-US). The effect of different pretreatments on the microstructure of blueberry epidermis was studied. The drying time of blueberries after HB, US-CIB, and CIB-US was decreased by 11.61%, 17.54%, and 17.27%, respectively, compared with control (33.75 h), and drying efficiency was significantly improved. Blueberries after pretreatments had higher content of polyphenol and anthocyanin, with an increase of 29.51-44.21% in phenol and 8.81-20.80% in anthocyanin, the antioxidant capacity of blueberries was also better than control and CIB enhanced the antioxidant capacity of blueberries. CIB-US can be used as an efficient pretreatment method for blueberry drying.

Anti-Hyperlipidemia, Hypoglycemic, and Hepatoprotective Impacts of Pearl Millet (Pennisetum glaucum L.) Grains and Their Ethanol Extract on Rats Fed a High-Fat Diet.

This study tested the anti-hyperlipidemic, hypoglycemic, hepatoprotective, and anti-inflammatory effects of whole pearl millet grain powder (MPG) and its ethanol extract (MPGethaolE) in obese rats fed a high-fat diet. The rats were divided into eight groups based on the treatments they received: control, high fat diet (HFD), HFD + MGE (25 mg/Kg), HFD + MPGethaolE (50 mg/Kg), HFD + MPGethaolE (100 mg/Kg), HFD + MPG (10%), HFD + MPG (20%), and HFD + MPG (30%). The final body weight, visceral, epididymal fat pads, and the liver weight were significantly decreased, in a dose-dependent manner, in HFD fed rats that were co-administered either the MPG powder or MPGethaolE. In the same line, serum levels of triglycerides (TGs), cholesterol (CHOL), and low-density lipoprotein-cholesterol (LDL-c), as well as fasting glucose, insulin, HOMA-IR, and serum levels of lipopolysaccharides (LPS), interleukine-6 (IL-6), interleukine-10 (IL-10), C-reactive protein (CRP), tumor necrosis factor (TNF-α), and adiponectin were progressively decreased while serum levels of high-density lipoproteins (HDL-c) were significantly increased when increasing the doses of both treatments. In conclusion, both the raw powder and ethanolic extract of MP have a comparative dose-dependent anti-obesity, hypoglycemic, hypolipidemic, anti-inflammatory, and anti-steatotic in HFD-fed rats.

Effect of vacuum impregnation assisted probiotics fermentation suspension on shelf life quality of freshly cut lotus root.

Probiotic fermentation suspension was used to extend the shelf life of freshly cut lotus root for the first time, which played a dual role of biological protection and quality maintenance. Fermentation suspension contained lactic acid bacteria (8-9 log CFU/mL) was prepared from juice of lotus root and used to immerse samples under atmospheric pressure and vacuum. Probiotic fermentation suspension inhibited microorganism and the activity of polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonia lyase (PAL), which slowed down the physiological reaction and was beneficial to maintain the color and hardness of tissues. Lactic acid bacteria antagonized other microorganisms, and metabolic acid production played a continuous role in preservation during storage. The vacuum was helpful for the fermentation suspension to be fully impregnated into samples. The probiotic fermentation suspension had a significant inhibitory effect on E.coli O157:H7, and extended lotus root shelf life from 3 to 9 days.

Inhibition of Lipid Accumulation and Adipokine Levels in Maturing Adipocytes by Bauhinia rufescens (Lam.) Stem Bark Extract Loaded Titanium Oxide Nanoparticles.

The present study reports a cost-effective, environmentally friendly method to increase the bioavailability and bio-efficacy of B. rufescens stem bark extract in the biological system via functional modification as B. rufescens stem bark nanoparticles (BR-TO2-NPs). The biosynthesis of BR- -NPs was confirmed by UV-visible (UV-vis) and Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction analyses. The shifts in FT-IR stretching vibrations of carboxylic and nitro groups (1615 cm-1), the O-H of phenolics or carboxylic acids (3405 cm-1), alkanes, and alkyne groups (2925 and 2224 cm-1) of the plant extract and lattice (455) indicated successful biosynthesis of BR- -NPs. Compared with the stem bark extract, 40 ng/dL dose of BR- -NPs led to a reduction in adipogenesis and an increase in mitochondrial biogenesis-related gene expressions, adiponectin-R1, PPARγC1α, UCP-1, and PRDM16, in maturing-adipocytes. This confirmed the intracellular uptake, bioavailability, and bio-efficiency of BR-TiO2-NPs. The lipid-lowering capacity of BR-TiO2-NPs effectively inhibited the metabolic inflammation-related gene markers, IL-6, TNF-α, LTB4-R, and Nf-κb. Further, BR-TiO2-NPs stimulating mitochondrial thermogenesis capacity was proven by the significantly enhanced CREB-1 and AMPK protein levels in adipocytes. In conclusion, BR-TiO2-NPs effectively inhibited lipid accumulation and proinflammatory adipokine levels in maturing adipocytes; it may help to overcome obesity-associated comorbidities.

Quercetin alleviates cadmium chloride-induced renal damage in rats by suppressing endoplasmic reticulum stress through SIRT1-dependent deacetylation of Xbp-1s and eIF2α.

Endoplasmic reticulum (ER) stress plays a key role in cadmium chloride (CdCl2)-induced nephrotoxicity. Sirtuin-1 (SIRT1) is a potent inhibitor of ER stress. In this study, we examined whether the protective effect of quercetin (QUR) against CdCl2-induced nephrotoxicity in rats involved modulation of SIRT1 and/or ER stress. Adult male rats were divided into five groups (n = 8, each) and treated for eight weeks as follows: control, control + QUR, CdCl2, CdCl2 + QUR, and CdCl2 + QUR + EX-527 (a SIRT1 inhibitor). Treatment of rats with QUR preserved the glomerulus and tubule structure, attenuated interstitial fibrosis, increased creatinine excretion, and reduced urinary levels of albumin, N-acetyl-ß-D-glucosaminidase, and ß2-microglobulin in CdCl2-treated rats. Concomitantly, QUR increased renal levels of Bcl-2, reduced mRNA levels of CHOP, and protein levels of Bax, caspase-3, and cleaved caspase-3, but failed to reduce the mRNA levels of GRP78, PERK, eIf2α, ATF-6, and xbp-1. QUR also reduced the renal levels of reactive oxygen species, tumour necrosis factor, and interleukin-6 and the nuclear activity of NF-κB in the control and CdCl2-treated rats but increased the nuclear activity of Nrf2 and levels of glutathione and manganese superoxide dismutase. Additionally, QUR increased the total levels and nuclear activity of SIRT1 and reduced the acetylation of eIf2α and xbp-1. The nephroprotective effects of QUR were abrogated by treatment with EX-527. Thus, QUR ameliorated CdCl2-induced nephrotoxicity through antioxidant and anti-inflammatory effects and suppressed ER stress mediated by the upregulation or activation of SIRT1-induced deacetylation of Nrf2, NF-κB p65, eIF2α, and xbp-1.

Intensive pulsed light pretreatment combined with controlled temperature and humidity for convection drying to reduce browning and improve quality of dried shiitake mushrooms.

BACKGROUND: The change of surface color caused by browning during the drying process of shiitake mushrooms seriously affects its market circulation. Intensive pulsed light (IPL) as a non-heat-treatment method can reduce enzyme activity by changing the enzyme structure. Therefore, in this study, the use of IPL pretreatment before drying was aimed to reduce the adverse reactions caused by the browning reaction during the drying processing of shiitake mushrooms. RESULTS: Shiitake mushrooms pretreated with 25 pulses of IPL energy of 400 J reduced the initial polyphenol oxidase enzyme activity, the browning index, and browning degree values by 42.83%, 43.02%, and 47.54% respectively. The IPL pretreatment enhanced the polysaccharides and reducing sugars contents and it reduced 5-hydroxymethylfurfural generation in the dried shiitake mushrooms. The pretreatment also improved the surface color, the antioxidant activity, and retained the umami taste characteristics in the dried shiitake mushroom. CONCLUSION: The IPL pretreatment combined with controlled temperature and humidity for convection drying could be a suitable method to improve the quality of dried shiitake mushrooms. Therefore, this study provides a new pretreatment method for materials that are prone to browning during drying. © 2021 Society of Chemical Industry.

Effects of single- and tri-frequency ultrasound on self-assembly and characterizations of bionic dynamic rat stomach digestion of pepsin-soluble collagen from chicken leg skin.

Chicken feet, aplenty by-products in the chicken industry, are rich in collagen and contain abundant amino acids so that it can be used as an important source for the collagen market. Pepsin-soluble collagen (PSC) was extracted from chicken leg skin and explored the effects of single- and tri-frequency ultrasound on the self-assembly and vitro digestion characteristics. By the diverging and tri-frequency ultrasound reactor, PSC was treated with 20 kHz/270w (C20H5m), 40 kHz/270w (C40H5m), 60 kHz/270w (C60H5m), 20/40/60 kHz/90w × 3 (CtH5m) for 5 min. Results showed that ultrasound could accelerate the process of collagen self-assembly, and 60 kHz/270w was the fastest. Microfiber diameters of C60H5m were 65-89 nm, which was significantly lower than the control without ultrasound (80-161 nm). The digestion results indicated polypeptides with relative molecular weights founded in the range 200-5000 Da were exceeded 85%. The final digested product had the highest content of oligopeptide, consistent rheological properties, and elastic behavior. The cavitation and mechanical of ultrasound have effects on the self-assembly process and collagen gel structure and digestion characteristics, which is of great significance for the development of the chicken industry and collagen market.

Vacuum pretreatment coupled to ultrasound assisted osmotic dehydration as a novel method for garlic slices dehydration.

This study investigated the effects of multi-frequency mode ultrasound and vacuum technology on the water loss (WL) of garlic slices during osmotic dehydration (OD), and their effects on the microstructure of garlic. A new method of OD for garlic slices was proposed - Vacuum pretreatment coupled to ultrasound assisted osmotic dehydration (VUOD). The results indicated that the WL of the garlic slices treated with VUOD (21.12%) was significantly (p < 0.05) higher than slices treated with normally OD (NOD) (10.67%), vacuum pretreatment OD (VOD) (14.18%), and multi-frequency mode ultrasound assisted OD (UOD) (11.20-13.56%). A mass transfer mechanism of VUOD was proposed. Low-field nuclear magnetic resonance results quantified the moisture migration in the vacuole, cytoplasm and intercellular space, and the cell wall of garlic cells. The quality properties (allicin content, surface color change and firmness) of VUOD treated garlic slices are predominately better than NOD, VOD and UOD treated samples.

Thermal and single frequency counter-current ultrasound pretreatments of sodium caseinate: enzymolysis kinetics and thermodynamics, amino acids composition, molecular weight distribution and antioxidant peptides.

BACKGROUND: Due to the disadvantages of traditional enzymolysis, pretreatments are crucial to enhance protein enzymolysis. Enzymolysis kinetics and thermodynamics, amino acids composition, molecular weight distribution, fluorescence spectroscopy and antioxidant activity of thermal (HT) and single frequency counter-current ultrasound (SCFU) pretreated sodium caseinate (NaCas) were studied. RESULTS: Enzymolysis of untreated NaCas (control) improved significantly (P < 0.05) by SFCU and followed by HT. Values of the Michaelis-Menten constant (KM ) of SFCU and HT were 0.0212 and 0.0250, respectively. HT and SFCU increased (P < 0.05) the reaction rate constant (k) by 38.64 and 90.91%, respectively at 298 K. k values decreased with increasing temperature. The initial activation energy (46.39 kJ mol-1 ) reduced (P < 0.05) by HT (39.66 kJ mol-1 ) and further by SFCU (33.42 kJ mol-1 ). SFCU-pretreated NaCas hydrolysates had the highest contents of hydrophobic, aromatic, positively and negatively charged amino acids. Medium-sized peptides (5000-1000 Da) are higher in SFCU (78.11%) than HT and the control. SFCU induced molecular unfolding of NaCas proteins. Accordingly, SFCU-pretreated NaCas hydrolysate exhibited the highest scavenging activity on DPPH and hydroxyl radicals, reducing power, and iron chelating ability. CONCLUSION: SFCU pretreatment would be a useful tool for production of bioactive peptides from NaCas hydrolysate. © 2016 Society of Chemical Industry.

Antioxidant peptides from corn gluten meal: Orthogonal design evaluation.

Protamex catalyzed corn gluten meal (CGM) hydrolysis peptides (CHP) were prepared. Orthogonal design L16 (4(5)) was used to optimize processing variables of CGM concentration, CGM heat pretreatment (121 °C) time, and enzymolysis pH, temperature, and time. Degree of hydrolysis (DH), undigested residue ratio, molecular weight (MW) distribution and DPPH radical inhibition were selected as analysis indicators. Optimum variables were CGM concentration of 18%, heat pretreatment time of 40 min, and enzymolysis pH, temperature and time of 7.5, 55 °C and 24h, respectively. Verification test showed that CHP IC50 for scavenging hydroxyl radical was the best and then followed by reducing power. Oligopeptides improved after hydrolysis at the expense of di- and tripeptides, suggesting formation of soluble aggregates from low MW peptides. The increase in the DH, oligopeptides, Alanyl-Tyrosine, and antioxidant free amino acids coincided with the improvement in the antioxidant activity of CHP.