Effect of freeze drying and oven drying on antioxidant properties of fresh wheatgrass

Wheatgrass-and-Aronia-Mixed Extract Suppresses Immunoglobulin E-Mediated Allergic Reactions In Vitro and In Vivo

Mast cells are an important component of immune responses. Immunoglobulin (Ig) E-sensitized mast cells release substances within minutes of allergen exposure, triggering allergic responses. Until now, numerous pharmacological effects of wheatgrass and aronia have been verified, but the effects of wheatgrass and aronia (TAAR)-mixed extract on allergic reactions have not been identified. Therefore, the aim of this study was to demonstrate the anti-allergic effect of TAAR extract on mast cell activation and cutaneous anaphylaxis. In this study, we investigated the anti-allergic effects and related mechanisms of TAAR extract in IgE-activated mast cells in vitro. We also assessed the ameliorating effect of TAAR extract on IgE-mediated passive cutaneous anaphylaxis mice in vivo. The TAAR extract significantly reduced the expression of β-hexosaminidase, histamine, and pro-inflammatory cytokines, which are mediators related to mast cell degranulation, via the regulation of various signaling pathways. The TAAR extract also regulated oxidative-stress-related factors through the Nrf2 signaling pathway. Additionally, treatment of TAAR extract to the passive cutaneous anaphylaxis mouse model improved ear thickness and local ear pigmentation. Taken together, our results suggest that TAAR extract is a potential candidate natural product to treat overall IgE-mediated allergic inflammation and oxidative-stress-related diseases by suppressing mast cell activity.

Structural change kinetics, drying characteristics, antioxidant properties, and the correlation between quality parameters of dried duckweed (Wolffia arrhiza (L.) Wimm) affected by different levels of microwave power

BACKGROUND

Duckweed is considered as a future food material due to its fast growth, high yield, high nutritional value, and low impact on land use. However, in its fresh form, it has high moisture content (95% wet basis), resulting in a short shelf life. In this study, microwave drying (MWD) was conducted to produce a shelf-stable duckweed with minimal loss of quality. Drying characteristics and quality aspects of dried duckweed were assessed. Reaction order kinetics, including zero and first order, was applied to describe structural changes during drying process. Hierarchical cluster analysis (HCA) was used to select the appropriate drying conditions.

RESULTS

Of five drying models, the Midilli-Kucuk model was the one that best described the drying process. Drying at high microwave power could reduce energy consumption and increase energy efficiency. Increasing both microwave power and drying time increased the structural shrinkage rate as described by first-order reaction kinetics. High correlations among quality parameters were observed using Pearson's correlation. Drying treatments were differentiated into two main clusters by HCA and the results showed that MWD at 720 and 900 W provided samples that were closer in terms of quality to a freeze dried sample (the positive control) than samples that had been subjected to MWD at 450 W.

CONCLUSION

Drying behaviors of duckweed were well-described by the Midilli-Kucuk model. Microwave drying at 900 W gave the lowest energy consumption and displayed the most efficient use of energy. The first-order equation could be used effectively to describe the structural changes in the duckweed. Microwave drying at 720 and 900 W was the appropriate drying condition according to the HCA classification. © 2023 Society of Chemical Industry.

Extract of Wheatgrass and Aronia Mixture Ameliorates Atopic Dermatitis-Related Symptoms by Suppressing Inflammatory Response and Oxidative Stress In Vitro and In Vivo

Atopic dermatitis is regulated by the production of pro-inflammatory cytokines and chemokines via the nuclear factor kappa B or mitogen-activated protein kinase signaling pathways, as well as, the release of oxidative stress-related factors via the NF-E2 p45-related factor 2 signaling pathway. Both wheatgrass (Triticum aestivum L., TA) and aronia (Aronia melanocarpa, AR) are known for their anti-inflammatory and antioxidant properties, however, the anti-inflammatory and antioxidant effects of TA and AR (TAAR) mixture extract have not been elucidated in an atopic dermatitis model. In this study, we assessed the inhibitory effects and underlying molecular mechanism of TAAR extract against lipopolysaccharide-induced inflammation and tumor necrosis factor-α/interferon-γ-induced inflammation and oxidative stress in vitro. We also investigated the alleviating effect of TAAR extract on DNCB-induced atopic dermatitis-like skin lesions in mice in vivo. We found that TAAR extract treatment inhibited inflammatory mediators in both RAW 264.7 cells and HaCaT cells, and increased the expression of oxidative stress defense enzymes in HaCaT cells. Furthermore, treatment of the DNCB-induced mouse model with TAAR extract ameliorated the overall symptoms of atopic dermatitis. Therefore, TAAR extract as a novel natural therapeutic agent may be used for the treatment of atopic dermatitis.

Freeze-Drying Processes Applied to Melon Peel: Assessment of Physicochemical Attributes and Intrinsic Microflora Survival during Storage

Melon peel is recognized as a source of healthy nutrients and oxidant compounds. Being considered a non-edible part with no profit value, large amounts of melon rinds are discharged by fruit industries. Innovative food ingredients with potential health benefits may arise if these parts were conveniently transformed. The objective was to freeze-dry small melon peel cubes to attain a potential edible matrix. An ozone pre-treatment was applied seeking decontamination purposes and quality retention. The effect of these processes was assessed in terms of physicochemical parameters (moisture content, water activity and color), bioactive compounds (total phenolics, vitamin C and chlorophylls) and antioxidant capacity, during 7 weeks of storage at room temperature. Intrinsic microflora (mesophylls, yeasts and molds) were also monitored. Results showed that the freeze-drying process allowed retention of the most bioactive compounds analyzed, except for total phenolic content. In this case, the ozone pre-treatment was important for phenolics preservation. During the storage period, ozonated samples presented a higher content of bioactive compounds. In terms of microflora, the ozone and freeze-drying effects were not significant. Freeze-drying proved to be a suitable preservation method for melon peel. The ozone impact was not relevant in terms of decontamination.

Anthocyanin Extraction Method and Sample Preparation Affect Anthocyanin Yield of Strawberries

Anthocyanins are a group of pigments with antioxidant activities that are present naturally in plants. The role of the pigment in human health and its quantitative analysis has attracted a lot of attention globally. A well-known and accurate method of anthocyanin quantification is based on spectrophotometric methods. However, these methods are subject to interference from impurities and need to be optimized for different plant matrixes and extraction conditions. Two experiments were designed to study (1) the effect of plant preparation methods (eg, fresh, frozen, and freeze-dried puree) on anthocyanin yield and (2) the effect of five anthocyanin extraction methods on anthocyanin yield of freeze-dried strawberry puree. Sample preparation methods did not have any effect on anthocyanin yield. Freeze-dried samples were used for their stability (ease of use and flexibility) to compare extraction methods. The anthocyanin yield was affected by the extraction method. Two methods containing chloroform gave the highest anthocyanin yield. One method with methanol:water:HCl gave intermediate results, and the pH differential and the other method with methanol:water:HCl (80:20:1) gave the lowest anthocyanin yields. Processing time (incubation time) was lowest in the pH differential method; however, the haze produced in this method may interfere with the spectrophotometric assessment of anthocyanins.

Total Anthocyanin Content of Strawberry and the Profile Changes by Extraction Methods and Sample Processing

Anthocyanins are the primarily pigments in many flowers, vegetables, and fruits and play a critical role in human and plant health. They are polyphenolic pigments that are soluble in water and usually quantified by spectrophotometric methods. The two main methods that quantify anthocyanins are pH differential and organic solvent-based methods. Our hypothesis was that these methods extract different anthocyanin profiles. Therefore, this experiment was designed to identify anthocyanin profiles that are extracted by pH differential and organic solvent-based methods and observe their total anthocyanin content from strawberries. Six methods were tested in this experiment to quantify and profile anthocyanins in strawberry fruits by spectrophotometry and Ultra High Performance Liquid Chromatography (UHPLC) respectively. Four methods used organic solvents (methanol, and chloroform-methanol) in different combinations. The next two methods were pH differential and a combination of organic solvent and the pH differential method. The results suggest that acidified chloroform-methanol extracted the highest anthocyanin content compared to water-based solvents. Methanol-water based solvents also performed better than methanol alone, because both methanol and water may extract different profiles of anthocyanins. Water-based extracts had the greatest absorbance at a lower wavelength (498 nm), followed by methanol (508 nm), and chloroform (530 nm). Chloroform-methanol solvent with higher pH (3.0) extracted pelargonidin as the main anthocyanin, while methanol and water-based solvents (with lower pH 1.0–2.0) extracted delphinidin as their main anthocyanin as identified by UHPLC. Therefore, chloroform-methanol and methanol-water solvents were the best solvents for extracting anthocyanins from strawberries. Also, freeze-dried strawberries had higher anthocyanin contents compared to fresh or frozen samples.

Extract of Triticum aestivum Sprouts Suppresses Acetaminophen-Induced Hepatotoxicity in Mice by Inhibiting Oxidative Stress

Wheat (Triticum aestivum L.) is the oldest known food crop, and many studies have reported that wheat shoots (i.e., wheatgrass) possess anti-cancer, anti-inflammatory, and antioxidant activities. However, the potentially ameliorative effect of wheat shoots on hepatotoxicity caused by high doses of N-acetyl-para-aminophenol (acetaminophen, APAP) has yet to be reported. C57BL/6 mice received daily oral TAE (100 or 200 mg/kg), positive control (silymarin 100 mg/kg), or negative control (saline vehicle) treatments for 7 days prior to intraperitoneal APAP injection. Histological, serum (ELISA), Western blotting, and quantitative PCR analyses of excised liver tissues were then performed. Pre-treatment with TAE (100 or 200 mg/kg) ameliorated APAP-induced pathological damage (i.e., hepatotoxic lesions), reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and also ameliorated APAP-induced increases in oxidative stress, thereby inhibiting oxidative liver damage and reducing the expression of inflammatory cytokines. In addition, TAE pre-treatment inhibited the expression of Cytochrome P4502E1 (CYP2E1), which is a key enzyme in the onset of APAP-induced hepatotoxicity, suppressed the expression of the target proteins regulated by the antioxidant enzyme Nrf2, and suppressed hepatocyte apoptosis. These findings suggest that TAE is an attractive therapeutic candidate that exhibits potential hepatoprotective activity by inhibiting oxidative stress, inflammation, apoptosis, and liver damage.

The Effect of Wheatgrass Lyophilizate on Blood Clotting Time in Rats

Wheatgrass is widely used in the alternative medicine, however, there is a lack of clinical evidence to support its efficacy. Although based on its chemical composition, data from animal experiments and clinical trials, the use of juice and extracts of Triticum shoots seems to be safe, clinical reports point out its potential interaction with oral anticoagulants. The aim of our study was to assess the interaction of wheatgrass with warfarin in rats and to assess its flavonoid content. Three groups of animals were treated orally with wheatgrass, warfarin, or the combination of wheatgrass and warfarin for five days. Clotting assays were performed using platelet-poor plasma. Prothrombin time was determined by optical and mechanical coagulometers. Flavonoid content of wheatgrass was measured by HPLC. The effect of wheatgrass on prothrombin time was not confirmed. Co-administration of wheatgrass and warfarin did not result in diminished anticoagulant activity. Low amount of flavonoids was detected in wheatgrass juice, the total flavonoid content was 0.467 mg/100 g lyophilized juice powder. The previously reported rutin, quercetin and apigenin was not detected by us. Our results do not confirm the probability of interaction of wheatgrass with oral anticoagulants. However, the low flavonoid content of wheatgrass does not support its use as an antioxidant.

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

Triticum aestivum sprout extract attenuates 2,4‑dinitrochlorobenzene‑induced atopic dermatitis‑like skin lesions in mice and the expression of chemokines in human keratinocytes

Atopic dermatitis (AD) is a common chronic, recurring, inflammatory skin disease. A number of researchers have been seeking safe AD therapies for a long time. Triticum aestivum sprouts (TAEE), known as wheatgrass, are one of the most widely used health foods worldwide. They show numerous beneficial effects, including anticancer, anti‑inflammatory, anti‑oxidant, anti‑obesity, anti‑colitis and anti‑allergy effects; however, their effect on AD is unknown. In the present study, the anti‑AD effects of a 70% ethanol extract of TAEE were investigated in 2,4‑dinitrochlorobenzene (DNCB)‑treated mice with AD‑like skin lesions and in tumor necrosis factor (TNF)‑α‑ and interferon (IFN)‑γ‑stimulated human keratinocytes (HaCaT cells). Oral administration of 200 mg/kg TAEE for 10 days significantly decreased the skin thickness, transepidermal water loss and serum immunoglobulin E levels in DNCB‑treated mice. In addition, TAEE reduced the secretion of inflammatory chemokines via regulation of the signal transducer and activator of transcription 1 and suppressor of cytokine signaling pathways in TNF‑α‑ and IFN‑γ‑stimulated HaCaT cells. These results indicate that TAEE may have beneficial effects in the treatment and prevention of AD and associated skin diseases.

Fabrication of Hybrid Collagen Aerogels Reinforced with Wheat Grass Bioactives as Instructive Scaffolds for Collagen Turnover and Angiogenesis for Wound Healing Applications

The present study illustrates the progress of the wheat grass bioactive-reinforced collagen-based aerogel system as an instructive scaffold for collagen turnover and angiogenesis for wound healing applications. The reinforcement of wheat grass bioactives in collagen resulted in the design and development of aerogels with enhanced physicochemical and biomechanical properties due to the intermolecular interaction between the active growth factors of wheat grass and collagen fibril. Differential scanning calorimetry analysis revealed an enhanced denaturation temperature when compared to those of native collagen aerogels. Fourier transform infrared spectroscopy analysis confirmed that the reinforcement of bioactives in the wheat grass did not affect the structural integrity of the collagen molecule. Additionally, the reinforced biomaterial with a systematic absorptive morphology resulted in a three-dimensional (3D) sponge-like aerogel exhibiting a potent highly oriented 3D structural assembly that showed increased water retention ability and substance permeability that would enable the passage of nutrients and gaseous components for cellular growth. Furthermore, the cumulative effect of the growth factors in wheat grass and the collagen molecule augments the angiogenic ability and collagen production of the aerogel by restoration of the damaged tissue thereby making it a potential 3D wound dressing scaffold. The results were confirmed by in vivo wound healing assays. This study shows the possibility for progress of a biocompatible, biodegradable, and nonadhesive nutraceutical-reinforced collagen aerogel as an instructive scaffold with good antimicrobial properties for collagen turnover and angiogenic response for wound healing applications.

Wheatgrass Extract Ameliorates Hypoxia-induced Mucin Gene Expression in A549 cells

BACKGROUND

Wheatgrass is known to have antioxidant, antiaging, and anti-inflammatory effect. However, its protective effect against hypoxia is not yet evaluated.

OBJECTIVE

In this study, we evaluated the protective and anti-inflammatory effect of wheatgrass against the hypoxia in airway epithelial cells.

MATERIALS AND METHODS

A549 human lung adenocarcinoma cells were incubated in a hypoxic condition (CO₂ 5%/O₂ 1%) for 24 hr in the presence of different concentration of wheatgrass 50, 75, 100, and 150 μg/mL, and the magnitude of each immunologic response produced by the A549 cells was compared. The mRNA expression level of mucin gene (MUC), 5A, 5B, 8, GM-CSF, TNF-α, and VEGF were evaluated by using real-time polymerase chain reaction. The MUC proteins level before and after knocking out the hypoxia-inducible factor (hif)-1α via short interfering (si) RNA transfection were assessed by immunoblot analysis. Accordingly, the involved cell signaling pathway was evaluated by immunoblot analysis.

RESULTS

The inflammatory cytokines (GM-CSF, TNF- α) and the expressions of MUC 5A, 5B, and 8 were augmented by hypoxia. The augmented MUC expression was decreased by the wheatgrass extract administration. Hif-1α gene expression after hypoxia exposure was decreased by wheatgrass. Knockdown of hif-1α by siRNA reduced the mucin gene expression and which was more enhanced by wheatgrass extract.

CONCLUSION

Theses results suggest that wheatgrass may be useful in the treatment of sinonasal disease by inhibiting mucus hypersecretion in airway epithelium.

SUMMARY

Wheatgrass extract decreases the hypoxia-induced MUC 5A, 5B and 8 expression.Hif-1α gene expression after hypoxia exposure was decreased by wheatgrass.Wheatgrass inhibits p44/42 phosphorylation in hypoxia-exposed airway epithelial cells. Abbreviations used: A549: human lung adenocarcinoma cells, GM-CSF: granulocyte-macrophage colony stimulating factor, HIF: hypoxia inducible factor, IL: interleukin, MUC: mucin, MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, TNF: tumor necrosis factors, VEGF: vascular endothelial growth factor, si RNA: short interfering RNA.

Wheatgrass extract inhibits hypoxia-inducible factor-1-mediated epithelial-mesenchymal transition in A549 cells

BACKGROUND/OBJECTIVES

Epithelial-mesenchymal transition (EMT) is involved in not only cancer development and metastasis but also non-cancerous conditions. Hypoxia is one of the proposed critical factors contributing to formation of chronic rhinosinusitis or nasal polyposis. Wheatgrass (Triticum aestivum) has antioxidant, anti-aging, and anti-inflammatory effects. In this study, we analyzed whether wheatgrass has an inhibitory effect on the EMT process in airway epithelial cells.

MATERIALS/METHODS

A549 human lung adenocarcinoma cells were incubated in hypoxic conditions (CO₂ 5%/O₂ 1%) for 24 h in the presence of different concentrations of wheatgrass extract (50, 75, 100, and 150 µg/mL) and changes in expression of epithelial or mesenchymal markers were evaluated by immunoblotting and immunofluorescence. Accordingly, associated EMT-related transcriptional factors, Snail and Smad, were also evaluated.

RESULTS

Hypoxia increased expression of N-cadherin and reduced expression of E-cadherin. Mechanistically, E-cadherin levels were recovered during hypoxia by silencing hypoxia inducible factor (HIF)-1α or administering wheatgrass extract. Wheatgrass inhibited the hypoxia-mediated EMT by reducing the expression of phosphorylated Smad3 (pSmad3) and Snail. It suppressed the hypoxia-mediated EMT processes of airway epithelial cells via HIF-1α and the pSmad3 signaling pathway.

CONCLUSION

These results suggest that wheatgrass has potential as a therapeutic or supplementary agent for HIF-1-related diseases.

The immunologically active oligosaccharides isolated from wheatgrass modulate monocytes via Toll-like receptor-2 signaling

Wheatgrass is one of the most widely used health foods, but its functional components and mechanisms remain unexplored. Herein, wheatgrass-derived oligosaccharides (WG-PS3) were isolated and found to induce CD69 and Th1 cytokine expression in human peripheral blood mononuclear cells. In particular, WG-PS3 directly activated the purified monocytes by inducing the expression of CD69, CD80, CD86, IL-12, and TNF-α but affected NK and T cells only in the presence of monocytes. After further purification and structural analysis, maltoheptaose was identified from WG-PS3 as an immunomodulator. Maltoheptaose activated monocytes via Toll-like receptor 2 (TLR-2) signaling, as discovered by pretreatment of blocking antibodies against Toll-like receptors (TLRs) and also determined by click chemistry. This study is the first to reveal the immunostimulatory component of wheatgrass with well defined molecular structures and mechanisms.