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Concept: Preservative


In vitro genotoxic effects of antioxidant additives, such as citric acid (CA) and phosphoric acid (PA) and their combination, as well as antimicrobial additives, such as benzoic acid (BA) and calcium propionate (CP), on human lymphocytes were determined using alkaline single-cell gel electrophoresis. There was a significant increase in the DNA damage in human lymphocytes after 1 h of in vitro exposure to CA, PA, BA and CP (200, 25-200, 50-500, 50-1000 μg/mL, respectively). The combination of CA and PA significantly increased the mean tail intensity at all the concentrations used (25-200 μg/mL) and significantly increased the mean tail length mainly after higher concentrations (100 and 200 μg/mL). Data in this study showed that the concentrations of food additives used induce DNA damage and PA was the most genotoxic and CA was less genotoxic additives among them.

Concepts: Protein, Acid, Carboxylic acid, Citric acid, E number, Vinegar, Food additive, Preservative


Sulfites and other preservatives are considered food additives to limit bacterial contamination, and are generally regarded as safe for consumption by governmental regulatory agencies at concentrations up to 5000 parts per million (ppm). Consumption of bactericidal and bacteriostatic drugs have been shown to damage beneficial bacteria in the human gut and this damage has been associated with several diseases. In the present study, bactericidal and bacteriostatic effects of two common food preservatives, sodium bisulfite and sodium sulfite, were tested on four known beneficial bacterial species common as probiotics and members of the human gut microbiota. Lactobacillus species casei, plantarum and rhamnosus, and Streptococcus thermophilus were grown under optimal environmental conditions to achieve early log phase at start of experiments. Bacterial cultures were challenged with sulfite concentrations ranging between 10 and 3780 ppm for six hours. To establish a control, a culture of each species was inoculated into media containing no sulfite preservative. By two hours of exposure, a substantial decrease (or no increase) of cell numbers (based on OD600 readings) were observed for all bacteria types, in concentrations of sulfites between 250-500 ppm, compared to cells in sulfite free media. Further testing using serial dilution and drop plates identified bactericidal effects in concentrations ranging between 1000-3780 ppm on all the Lactobacillus species by 4 hours of exposure and bactericidal effects on S. thermophilus in 2000ppm NaHSO3 after 6 hours of exposure.

Concepts: Bacteria, Gut flora, Microbiology, Probiotic, Lactobacillus, Preservative, Sulfur dioxide, Firmicutes


The economic burdens and health implications of food spoilage are increasing. Contamination of food sources by fungi, bacteria, yeast, nematodes, insects, and rodents remains a major public health concern. Research has focused on developing safer natural products and innovations to meet consumers' acceptance as alternatives to synthetic food preservatives. Many recent novel preservative techniques and applications of both natural and synthetic origin continue to proliferate in food and chemical industries. In particular, some essential oils of plant origin are potent food preservatives and are thus attractive alternatives to synthetic preservatives. This paper provides an overview of recent advances and future prospects in assessing the efficacy of theuse of Cymbopogon citratus (lemongrass) essential oil in food preservation. The possible mechanisms of action and toxicological profile as well as evidence for or against the use of this essential oil as an alternative to synthetic food preservatives in domestic and industrial applications are discussed.

Concepts: Food, Food preservation, Preservative, Essential oil, Oil, Oils, Cymbopogon, Cymbopogon citratus


Sulphiting agents are well-known food preservatives. The European legislation does not allow their addition in fresh meat preparations. Therefore this type of food products has often been verified. To high sulphite levels in food is a health safety risk, due to toxic effects that these compounds may exercise on humans. In this study the control activity as performed by an Italian accredited laboratory from 2013 to 2015, relating to determination of sulphites in meat products, is described. Six hundred and sixty-nine meat product samples were analysed. Both applied techniques, a screening method (malachite green test) and a confirmatory method (ion chromatography), were accredited. 43 samples resulted positive at screening test and 19 of these samples showed high sulphites concentrations, in the range 67.6 - 1437 mg kg(-1). The non-negligible percentage of positives (6.4%) and the high concentrations verified, confirmed that the control of sulphuring treatment of fresh meat preparations is an important task for organisations in charge of food inspections and control.

Concepts: Nutrition, Type I and type II errors, Chemistry, Sulfur, Preservative, Sulfur dioxide, Sulfite, Sulfites


HbA1c is used in forensic toxicology to identify undiagnosed diabetes mellitus (DM) and those with poor glycemic control prior to death. HbA1c is typically measured in whole blood collected in tubes containing ethylenediaminetetraacetic acid (EDTA). The effect of other additives, including sodium fluoride (NaF), is unclear. Furthermore, the assessment of short- and long-term stability of HbA1c has produced conflicting results. In this study, we collected paired postmortem blood samples in EDTA and NaF tubes (n = 142) to assess their comparability for HbA1c measurement. Stability was assessed by measuring HbA1c at baseline, 2, 3, and 4 weeks postcollection (stored at 4°C) and at 2, 4, 6, and 12 months postcollection (stored at -20°C). We found no significant difference in HbA1c between the two preservatives at any of the time points indicating NaF is a suitable preservative for HbA1c measurement. We also determined that DM status, postmortem interval, and decomposition had no effect on stability.

Concepts: Diabetes mellitus, Measurement, Diabetes, EDTA, Systems of measurement, Preservative


Essential oils are concentrated liquids of complex mixtures of volatile compounds and can be extracted from several plant organs. Essential oils are a good source of several bioactive compounds, which possess antioxidative and antimicrobial properties. In addition, some essential oils have been used as medicine. Furthermore, the uses of essential oils have received increasing attention as the natural additives for the shelf-life extension of food products, due to the risk in using synthetic preservatives. Essential oils can be incorporated into packaging, in which they can provide multifunctions termed “active or smart packaging.” Those essential oils are able to modify the matrix of packaging materials, thereby rendering the improved properties. This review covers up-to-date literatures on essential oils including sources, chemical composition, extraction methods, bioactivities, and their applications, particularly with the emphasis on preservation and the shelf-life extension of food products.

Concepts: Food, Chemical substance, Chemical compound, Food processing, Food preservation, Food additive, Preservative, Packaging


Consumers demand more and more so-called “natural” products and, therefore, the aim of this work was to compare the effects of natural versus synthetic antioxidant preservatives in yogurts. Matricaria recutita L. (chamomile) and Foeniculum vulgare Mill. (fennel) decoctions were tested as natural additives, while potassium sorbate (E202) was used as a synthetic additive. The fortification of yogurts with natural and synthetic antioxidants did not cause significant changes in the yoghurt pH and nutritional value, in comparison with control samples (yogurt without any additive). However, the fortified yogurts showed higher antioxidant activity, mainly the yogurts with natural additives (and among these, the ones with chamomile decoction). Overall, it can be concluded that plant decoctions can be used to develop novel yogurts, by replacing synthetic preservatives and improving the antioxidant properties of the final product, without changing the nutritional profile.

Concepts: Antioxidant, Food additive, Preservative, Preservatives, Matricaria recutita, Fennel, Matricaria, Potassium sorbate


Spices are parts of plants that due to their properties are used as colorants, preservatives or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol) and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices and the advantages and disadvantages of their use.

Concepts: Nutrition, Antioxidant, Cinnamon, Preservative, Eugenol, Spice, Clove, Spices


A new transformation of methylene-bis(phosphonic dichloride) into tetrathiobisphosphonate derivatives is reported. The reaction of methylene-bis(phosphonic dichloride) with 1,2-ethanedithiol in bromoform in the presence of AlCl3 formed methylene-bis(1,3,2-dithiaphospholane-2-sulfide), which gave rise to O,O'-diester-methylenediphosphonotetrathioate analogues 1a-k upon reaction with phenols and alkyl alcohols in the presence of DBU. Reaction mechanisms are proposed and all products were characterized by (31)P, (13)C, and (1)H-NMR. An X-ray crystal structure was obtained for intermediate 2. The potential of the novel scaffold for selective coordination of metal-ions was examined by coordination of Hg(II) and Pb(II) by 1f, as determined by FT-IR; and chelation of Zn(II), but not Ca(II) by 1b, as determined by (31)P/(1)H-NMR. UV/Vis measurements of 1g-Ni(II) mixture revealed a 2:1 ligand : metal complex. These derivatives are potential antioxidants, and their ability to inhibit ·OH formation in Fenton reactions was quantified by ESR measurements. Analogue 1g proved to be a most potent antioxidant (IC(50) 53 μM), inhibiting the Cu(I)-catalyzed Fenton reaction at lower concentrations than GSH, ascorbic acid, and EDTA. Analogue 1c inhibited the Fe(II)-catalyzed Fenton reaction at about the same concentrations as ascorbic acid (IC(50) 83 vs. 93 μM). In summary, the novel compounds, 1a-k, proved to chelate various borderline / soft Lewis acid metal-ions, and may be useful as antioxidants and metal extractors.

Concepts: Acid, Antioxidant, Ligand, Coordination chemistry, Vitamin C, Preservative, Fenton's reagent, Ascorbic acid


Mushroom extracts contain bioactive compounds potentially useful to functionalize foodstuffs. Herein, alcoholic extracts of Agaricus bisporus were studied for their bioactivity and viability as functional ingredients in a food product with high water content (yogurt). Extracts were microencapsulated (to improve their stability and hydrophilicity) by spray-drying, using maltodextrin crosslinked with citric acid as encapsulating material. The effect of thermal treatment (after atomization) on crosslinking and bioactivity of microspheres was tested. The incorporation of free and thermally untreated forms resulted in yogurts with higher initial antioxidant activity (EC50 values: 214 and 272 mg.mL-1) that decreased after 7 days (EC50 values: 248 and 314 mg.mL-1). Contrarily, thermally treated microencapsulated extracts showed higher antioxidant activity after the same period (EC50 values, 0 days: 106 mg.mL-1; 7 days: 48.7 mg.mL-1), in result of an effective protection provided by microencapsulation with crosslinked maltodextrin and citric acid. Functionalized yogurts showed an overall maintenance of nutritional properties.

Concepts: Acid, Nutrition, Citric acid, Vinegar, Preservative, Mushroom, Agaricus bisporus, Agaricus