High-Quality Bioethanol and Vinegar Production from Saudi Arabia Dates: Characterization and Evaluation of Their Value and Antioxidant Efficiency

The Chemical Profiles and Antioxidant Properties of Live Fruit or Vegetable Vinegars Available on the Polish Food Market

Live vinegar is a product formed through a two-step fermentation process of a sugar substrate that has not been subjected to filtration or pasteurization. This is considered to preserve all nutrients and biologically active microorganisms, making it a product with a valuable composition and beneficial properties. Therefore, the purpose of this study was to analyze the chemical composition and antioxidant properties of the selected vinegars available on the Polish food market. The material in the study consisted of four live (naturally turbid, unfiltered, unpasteurized) fruit or vegetable vinegars: apple, pear, rhubarb, and lemon. Spectrophotometric, HPLC, and GC methods were used. Among the vinegars tested, lemon vinegar had the highest vitamin C content-15.95 mg/100 mL. Apple vinegar proved to be the best source of polyphenols and flavonoids (TPC-191.97 mg GAE/L, TFC-70.22 mg RE/L). All of the vinegars contained dihydroxybenzoic acid, 4-hydroxybenzoic acid, caffeic acid, 2-hydroxycinnamic acid, and myricetin. The acetic acid content of the tested vinegars ranged from 29.180 to 38.125 mM/L. The pH values ranged from 3.14 to 3.41. In conclusion, the most promising nutraceutical with potentially beneficial health-promoting properties seems to be apple vinegar.

Date Vinegar: First Isolation of Acetobacter and Formulation of a Starter Culture

There is a lack of scientific analysis and control over the production of date vinegar in Oman, despite its growing demand in the worldwide market. Traditional production of date vinegar may lead to elevated amounts of ethanol (≥0.5%) and reduced content of acetic acid (<4%) compared to the standard acceptable levels. This study aimed to isolate non-Gluconobacter species from date vinegar produced by spontaneous fermentation and formulate starter cultures for quick and efficient production of date vinegar. In spontaneous fermentation date vinegar samples, the highest concentration of acetic acid was 10.42% on day 50. Acetobacter malorum (5 isolates), A. persici (3 isolates), and A. tropicalis (3 isolates) were identified based on 16S rRNA gene sequences for the first time in date vinegar. For date vinegar prepared with a starter culture of Acetobacter and yeast, the highest concentration of acetic acid was 4.67%. In conclusion, spontaneous fermentation resulted in the production of date vinegar with a high concentration of acetic acid, acceptable concentrations of ethanol and methanol, and the first isolation of three Acetobacter species. The formulated starter culture produced acceptable amounts of acetic acid and the time of fermentation was reduced 10 times (from 40 days to 4 days). This can provide the basis for producing a personalized or commercial product that ensures the production of good-quality date vinegar in an easier, faster, safer, and more efficient way from low-quality and surplus dates.

The Complexity of Chinese Cereal Vinegar Flavor: A Compositional and Sensory Perspective

With a millennium-long history, traditional Chinese cereal vinegar (CCV) is a significant part of China's cultural heritage. The unique flavor of CCV is derived from the use of cereal and its bran as raw materials and solid-state fermentation as a brewing technique. This paper systemically summarized recent research progress on the aroma compounds in CCV, the biochemical generation of aroma compounds during the brewing process, and the association between sensory perception and the primary aroma compounds. Furthermore, a complete CCV lexicon and sensory wheel prototype were constructed. This study aims to lay a foundation for future CCV aroma research, quality improvement, and industrialization.

Preparation, chemical profiles, antioxidative activities, and angiotensin-converting enzyme 2 inhibitory effect of date fruit vinegar

Date palm (Phoenix dactylifera L.) is an important commercial crop extensively consumed as a staple food and has been applied in many ethnomedical systems. Fruit vinegar is a preservative, condiment, and beverage with a spectrum of health benefits. Studies about the preparation, chemical profiles, and bioactivities of date fruit vinegar (DFV) are fundamental requirements for industrialization production. This study focused on the lab-scaled producing conditions, chemical profiles of DFV, and its bioactivities in vitro. According to the results, a date wine containing 9.75% methanol was obtained by yeast fermenting the enzyme-hydrolyzed date juice with 23.11% ± 0.39% of total sugar content. The optimized acidic fermentation conditions were an inoculation amount of 0.02%, a fermentation temperature of 31.14°C, and an initial alcohol content of 7.78%. Total acidity and total phenolic contents of the DFV were 7.74% ± 0.29% and 1.44 mg gallic acid equivalent/mL, respectively. In total, 32 organic acids were quantitated in the unaged DFV, with acetic, L-malic, and oxoglutaric acids as the predominant compounds. A total of 930 volatiles were identified in the DFV, including 186 esters, 177 terpenoids, and 148 heterocyclic compounds. There are 18 phenolic acids presented in the DFV. In addition, 42 flavonoids were quantitated in the DFV, including catechin, taxifolin, and cynaroside. The results of free radical scavenging activities and reducing power demonstrated that the DFV displayed good antioxidant properties. The DFV also acted well on angiotensin-converting enzyme 2 inhibition. These results suggest that the DFV can be industrially developed as a dietary supplement.

Deciphering the mechanism of jujube vinegar on hyperlipoidemia through gut microbiome based on 16S rRNA, BugBase analysis, and the stamp analysis of KEEG

Background

Growing data indicate that the gut microbiome may contribute to the rising incidence of hyperlipoidemia. Jujube vinegar lowers lipids, protects the liver, and reduces oxidant capacity, however, it is unknown whether this is due to the gut flora. To further research the role of the gut microbiome in treating hyperlipidemia with jujube vinegar, we looked into whether the action of jujube vinegar is related to the regulation of the gut microbiome.

Method

Thirty male ICR mice were used. The control group (CON), the high-fat diet (HFD) group, and the vinegar group (VIN) each consisted of ten female ICR mice fed consistently for eight weeks. For each treatment, we kept track of body mass, liver index, blood lipid levels, and oxidative stress state. We also analyzed mouse feces using high-throughput 16srRNA sequencing to examine the relationship between jujube vinegar's hypolipidemic effect and antioxidant activity and how it affects the gut microbiome.

Results

Jujube vinegar reduced body weight by 19.92%, serum TC, TG, and LDL-C by 25.09%, 26.83%, and 11.66%, and increased HDL-C by 1.44 times, serum AST and ALT decreased by 26.36% and 34.87% respectively, the blood levels of SOD and GSH-Px increased 1.35-fold and 1.60-fold, respectively. While blood MDA decreased 33.21%, the liver's SOD and GSH-Px increased 1.32-fold and 1.60-fold, respectively, and the liver's MDA decreased 48.96% in HFD mice. The gut microbiome analysis revealed that jujube vinegar increased the intestinal microbial ASV count by 13.46%, and the F/B (Firmicutes/Bacteroidota) ratio by 2.08-fold in high-fat diet mice, and the proportion was significantly inversely correlated with TC, TG, and LDL-C and positively correlated with HDL-C. Biomarker bacteria in the vinegar group included Lactobacillaceae and Lactobacillus, which correlated favorably with HDL-C, SOD, and GSH-Px and negatively with LDL-C, TC, and TG. Jujube vinegar increased the abundance of the Aerobic, Contains Mobile Elements, and Facultative Aerobic by 2.84 times, 1.45 times, and 2.40 times, while decreased the abundance of Potential pathogens by 44.72%, according to the BugBase study. The KEGG analysis showed that jujube vinegar was predominantly reflected in the biological process of gene function and related to signal transduction pathways, including glucagon signaling system, HIF-1 signaling pathway, adipocytokine signaling pathway, amino sugar, and nucleotide sugar metabolism, and so forth.

Conclusion

Based on these findings, jujube vinegar may reduce hyperlipoidemia by controlling the gut microbiome and enhancing antioxidant capacity.

Structural Characterization of Polysaccharides from Coriandrum sativum Seeds: Hepatoprotective Effect against Cadmium Toxicity In Vivo

Coriandrum sativum is one of the most widespread curative plants in the world, being vastly cultivated in arid and semi-arid regions as one of the oldest spice plants. The present study explored the extraction of polysaccharides from Coriandrum sativum seeds and the evaluation of their antioxidant potential and hepatoprotective effects in vivo. The polysaccharide from coriander seeds was extracted, and the structural characterization was performed by FT-IR, UV-vis, DSC, NMR (1D and 2D), GC-MS, and SEC analysis. The polysaccharide extracted from Coriandrum sativum (CPS) seeds was characterized to evaluate its antioxidant and hepatoprotective capacities in rats. Results showed that CPS was composed of arabinose, rhamnose, xylose, mannose, fructose, galactose, and glucose in molar percentages of 6.2%, 3.6%, 8.8%, 17.7%, 5.2%, 32.9%, and 25.6%, respectively. Further, CPS significantly hindered cadmium-induced oxidation damage and exercised a protective effect against Cd hepatocytotoxicity, with a considerable reduction in MDA production and interesting CAT and SOD enzyme levels. Results suggest that CPS might be employed as a natural antioxidant source.

Extraction, Characterization, and Antioxidant Activity of Polysaccharides from Ajwa Seed and Flesh

The date palm has been cultivated in dry and hot areas of the planet for much of human history. In the Kingdom of Saudi Arabia, dates are the main crop used as a source of food. Among several species of date fruits, the Ajwa AL-Madinah date is unique, growing only in Al-Madinah geographical region. The Ajwa date is used in traditional medicine due to its abundant active components and therapeutic properties. This study investigates the structural properties and the antioxidant effects of water-soluble polysaccharides extracted from Ajwa flesh and seed. The polysaccharides were isolated by two techniques including hot water and ultrasonic extraction. After isolation and partial purification, the physicochemical properties of four samples of polysaccharides extracted from flesh and seed were studied by several techniques including FTIR, solid-state NMR, elemental analysis, and mass spectrometry. Several radical scavenging experiments were combined to study the antioxidant activity of the polysaccharide compounds. FTIR and NMR results showed a structure typical of heterogeneous polysaccharides. Mass spectrometry revealed that the polysaccharide samples were composed mainly of mannose, glucose, galactose, xylose, arabinose, galacturonic acid, and fucose. In addition, the physicochemical properties and composition of polysaccharides extracted from flesh and seed were compared. The extracted polysaccharides showed antioxidant activity, with 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, Fe chelating ability, hydroxyl free radical scavenging ability, and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging. These results highlight their potential to be a useful nutritional element or supplemental medication.

Inversion Theory Leveling as a New Methodological Approach to Antioxidant Thermodynamics: A Case Study on Phenol

Antioxidants are various types of compounds that represent a link between biology and chemistry. With the development of theoretical and computational methods, antioxidants are now being studied theoretically. Here, a novel method is presented that aims to reduce the estimated wall times for DFT calculations that result in the same or higher degree of accuracy in the second derivatives over energy than is the case with the regular computational route (i.e., optimizing the reaction system at a lower model and then recalculating the energies at a higher level of theory) by applying the inversion of theory level to the universal chemical scavenger model, i.e., phenol. The resulting accuracy and wall time obtained with such a methodological setup strongly suggest that this methodology could be generally applied to antioxidant thermodynamics for some costly DFT methods with relative absolute deviation.

Impact of Calcium and Nitrogen Addition on Bioethanol Production by S. cerevisiae Fermentation from Date By-Products: Physicochemical Characterization and Technical Design

Given crude oil prices and their environmental impacts, the use of sustainable renewable alternative energies such as biofuels is rapidly progressing in numerous countries. Among biofuels, bioethanol is a renewable and clean fuel that can be obtained from the fermentation of several raw agricultural materials, including date fruit. However, the low product yield, mainly due to the low-grade nutrient content, limits its use as a promising alternative biofuel. This current study investigated bioethanol production from date by-products in Saudi Arabia and examined the impact of calcium and nitrogen sources added at different concentrations (0 to 1 g/L) on the productivity and ethanol concentration using Saccharomyces cerevisiae. Yeast extracts and ammonium chloride (NH4Cl) were tested as nitrogen sources for bioethanol fermentation from date juice. Calcium chloride (CaCl2) and calcium carbonate (CaCO3) were evaluated as calcium sources for the same purpose mentioned above. The results showed that both calcium and nitrogen sources improved ethanol production efficiencies. The addition of calcium sources such as CaCl2 at 0.4 g/L resulted in maximum ethanol concentration (41.5 ± 0.85 g/L) and the highest productivity of 0.511 g/L/h. Thus, an increase of 31.3% compared to the control sample was acquired. Ammonium chloride was found to be the best nitrogen supplement among them. Indeed, supplementing the fermentation medium with 1 g/L NH4Cl gave an optimal ethanol concentration and productivity, reaching more than 65 g/L and 0.83 g/L/h, respectively. This is an increase of 106.6%. The functional group of ethanol (C2H5OH) for all the elaborated samples was confirmed by Fourier-transform infrared spectroscopy (FTIR) and NMR analyses. Moreover, the results confirmed the high quality and purity of the bioethanol products. Thus, the “Khodhari” date variety of low market value is a privileged substrate for industrial bioethanol production. For this reason, a proposed flow diagram of a designed plant for bioethanol industrialization is provided and detailed.

Characterization of Polysaccharides Sequentially Extracted from Allium roseum Leaves and Their Hepatoprotective Effects against Cadmium Induced Toxicity in Mouse Liver

Allium roseum is one of the medicinal plants of the Liliaceae family, widely used in the food industry and traditional medicine. It is known for its various biological properties, such as its antioxidant, antiviral, antidiabetic, and anti-inflammatory activities. The present work aims to extract the polysaccharides from Allium roseum leaves and evaluate their antioxidant activities and hepatoprotective effects in vivo. Three polysaccharides from the leaves of Allium roseum were sequentially extracted in three media: water, chelating, and basic, respectively. They were characterized by size exclusion chromatography, gas chromatography mass spectrometry, FTIR-ATR, and NMR spectroscopy (1D and 2D). The different polysaccharides principally consist of glucose, galactose, mannose, rhamnose, xylose, and galacturonic acid. The antioxidant activity and hepatoprotective effect of the extracts against Cd-caused oxidative stress in liver mouse were tested. Cd treatment, during 24 h, enhanced significantly lipid peroxidation by a high production of malondyaldehyd (MDA) and superoxide dismutase (SOD) activity. In contrast, catalase activity (CAT) was decreased after the same period of exposure to the metal. The polysaccharides pre-treatment improved the antioxidant defense system to a great degree, mainly explained by the modulating levels of oxydative stress biomarkers (MDA, SOD, and CAT). This research clearly shows that Allium roseum polysaccharides, especially those extracted in aqueous medium, can be used as natural antioxidants with hepatoprotective properties.