HERB EXTRACT INFLUENCE ON THE OXIDATIVE STABILITY OF SELECTED LIPIDS

Antioxidant-Enhanced Alginate Beads for Stabilizing Rapeseed Oil: Utilizing Extracts from Post-Distillation Waste Residues of Rosemary

An eco-friendly extraction process of polyphenols from conventional dried rosemary tissues and post-distillation waste residues was applied using β-cyclodextrin as a co-solvent. The aqueous extracts were characterized by measuring the total phenolic content, and their phenolic compounds were identified and quantified by LC-MS. Sodium alginate solutions (2% w/w) with/without incorporation of rosemary aqueous extracts were prepared and used for the preparation of O/W emulsions containing 20% rapeseed oil and an 80% water phase. Hydrogel beads were then stored at 20 °C for 28 days. The quality of encapsulated oil during storage was evaluated by measurements of the peroxide value, p-anisidine value, free fatty acids, total oxidation value, and fatty acid composition, whilst the aqueous phase of the beads was analyzed for its total extractable phenolic content (TEPC). The experimental findings indicate that the incorporation of aqueous extracts from post-distillation rosemary residues in emulsion-filled hydrogel beads resulted in the lowest level of oxidation products in the encapsulated rapeseed oil (PV = 10.61 ± 0.02 meq/Kg oil, p-AnV = 4.41 ± 0.09, and FFA = 0.14 ± 0.00, expressed as % oleic acid content), indicating an acceptable oil quality until the end of the storage period.

The Effect of Peppermint and Thyme Oils on Stabilizing the Fatty Acid Profile of Sunflower Oil

Presently, there is an increasing shift towards the utilization of natural antioxidants and compounds with protective attributes for fatty acids in order to replace synthetic counterparts that may pose health risks. This transition aligns with the growing emphasis on promoting healthy and organic food choices. Essential oils stand out in this context due to scientific validations of their antioxidant properties. There are few published research results concerning changes in the fatty acid composition in model systems with the addition of essential oils. This study aims to investigate the impact of incorporating peppermint and thyme oils on inhibiting changes in the fatty acid profile of sunflower oil stored at both room temperature with exposure to daylight and in a thermostat set at 40 °C. The experimental procedure involved the addition of peppermint and thyme oils, along with butylated hydroxyanisole (BHA), to batches of sunflower oil. The samples were then stored for 11 months. The study observed a detrimental influence of storage conditions on the quantitative changes in the fatty acid profile of the sunflower oil. The addition of BHA stabilized the content of linoleic acid in the sunflower oil (approximately 53 g/100 g of linoleic acid compared to approximately 58 g/100 g in the control sample). Meanwhile, the model system of sunflower oil with the addition of peppermint and thyme oils (40 °C) exhibited a statistically significant decrease in the concentration of linoleic acid to approximately 8 g/100 g after eleven months of thermostating. Similar trends to those observed for linoleic acid were noted for the total fatty acid content in the sunflower oil. Notably, the efficacy of the selected substances in inhibiting adverse transformations in fats was contingent upon their concentration and the storage temperature.

Elderberry Diet Restores Spermatogenesis in the Transient Scrotal Hyperthermia-Induced Mice

Over the past years, several studies have also reported the adverse effects of hyperthermia on normal testicular tissues in several species including mice, rats, and humans. These deleterious impacts include temporarily drop in relative weight of testis along with a temporary partial or complete infertility. Sambucus nigra, also known as elderberry or sweet elder, is a source of bioactive compounds that has drawn growing attention for its potential beneficial effects in preventing and treating several diseases. This experimental research divided 30 mice into the following three groups: (1) control, (2) hyperthermia, and (3) hyperthermia receiving elderberry diet for 35 days. Scrotal hyperthermia was induced by water bath with 43 °C for 30 min. Then, the mice were euthanized, and their sperm samples were collected for sperm parameters analysis. Then, we took the testis samples for histopathological experimentations, immunohistochemistry against TNF-α and caspase-3 and serum testosterone, FSH and LH levels. Our outputs indicated that elderberry diet could largely improve the sperms parameters and stereological parameters, like spermatogonia, primary spermatocyte, round spermatid, and Leydig cells together with an increasing level of the serum testosterone compared to the scrotal hyperthermia induced mice. In addition, it was found that the expression of TNF-α and caspase-3 significantly decreased in the treatment groups by elderberry diet compared to the scrotal hyperthermia-induced mice. In conclusion, it could be concluded that elderberry diet may be regarded as an alternative treatment for improving the spermatogenesis process in the scrotal hyperthermia induced mice.

Effect of Herbal Addition on the Microbiological, Oxidative Stability and Sensory Quality of Minced Poultry Meat

The study aimed to assess the effect of herbal additions with antioxidant properties (pepper, thyme and oregano) on the microbiological and oxidative stability as well as the sensory quality of minced poultry meat. Meatballs treatments without additives and treatments with the addition of three types of spices in two forms—dry spices and industrial extracts were examined. Popular seasoning additives of oregano (Origanum vulgare), thyme (Thymus vulgaris) and black pepper (Piper nigrum) at 0.3% of dry herbal or 0.003% as industrial extract were added to minced meat. The microbiological, chemical and sensory tests were performed at specified times and storage temperature. Based on the studied criteria, products maintained constant and adequate quality by up to 10 days while stored in 4 °C. In the case of all tested samples, the overall sensory quality began to deteriorate after 10 days of storage. The preservative role of herbs and extracts in meat products during processing and storage was observed. Oregano and black pepper in both forms maintained good microbial quality and showed their inhibitory effects on the growth of psychrotrophic bacteria. It was observed that dried herbs revealed a stronger antioxidant effect than additives in the form of extracts. The studied dried herbs played an antioxidant, antimicrobial and preservative role in meat products during processing and storage.

Optimization of Extraction Conditions for the Antioxidant Potential of Different Pumpkin Varieties (Cucurbita maxima)

Antioxidants are a wide group of chemical compounds characterized by high bioactivity. They affect human health by inhibiting the activity of reactive oxygen species. Thus, they limit their harmful effect and reduce the risk of many diseases, including cardiovascular diseases, cancers, and neurodegenerative diseases. Antioxidants are also widely used in the food industry. They prevent the occurrence of unfavourable changes in food products during storage. They inhibit fat oxidation and limit the loss of colour. For this reason, they are often added to meat products. Many diet components exhibit an antioxidative activity. A high antioxidative capacity is attributed to fruit, vegetables, spices, herbs, tea, and red wine. So far, the antioxidative properties of various plant materials have been tested. However, the antioxidative activity of some products has not been thoroughly investigated yet. To date, there have been only a few studies on the antioxidative activity of the pumpkin, including pumpkin seeds, flowers, and leaves, but not the pulp. The main focus of our experiment was to optimize the extraction so as to increase the antioxidative activity of the pumpkin pulp. Variable extraction conditions were used for this purpose, i.e., the type and concentration of the solvent, as well as the time and temperature of the process. In addition, the experiment involved a comparative analysis of the antioxidative potential of 14 pumpkin cultivars of the Cucurbita maxima species. The study showed considerable diversification of the antioxidative activity of different pumpkin cultivars.

Antioxidative, potentially anti-inflammatory, and antidiabetic properties, as well as oxidative stability and acceptability, of cakes supplemented with elicited basil

The aim of the study was to investigate the effect of addition of basil elicited with jasmonic acid (JA) on the biological properties, oxidative stability, and sensory quality of cakes. Simulated gastrointestinal digestion was used for determination of bioavailability. The antioxidant, anti-inflammatory and antidiabetic potential of fortified cakes were significantly higher than those of the control cakes. The antioxidant activity of the tested cakes was increased after addition of basil, proportionally to the amount of the additive. Additionally, in some cases, better results were obtained using JA-elicited basil instead of the control basil. Basil addition inhibited fat peroxidation in the cakes, measured as the malondialdehyde content. Cakes supplemented with the control and elicited basil were characterized by satisfactory consumer acceptability. Based on the data obtained in the present study, it can be concluded that JA-elicited basil (especially elicited with 100µM jasmonic acid) can be recommended for food technologists.

Combined effect of carnosol, rosmarinic acid and thymol on the oxidative stability of soybean oil using a simplex centroid mixture design

BACKGROUND

Oxidation taking place during the use of oil leads to the deterioration of both nutritional and sensorial qualities. Natural antioxidants from herbs and plants are rich in phenolic compounds and could therefore be more efficient than synthetic ones in preventing lipid oxidation reactions. This study was aimed at the valorization of Tunisian aromatic plants and their active compounds as new sources of natural antioxidant preventing oil oxidation.

RESULTS

Carnosol, rosmarinic acid and thymol were isolated from Rosmarinus officinalis and Thymus capitatus by column chromatography and were analyzed by nuclear magnetic resonance. Their antioxidant activities were measured by DPPH, ABTS and FRAP assays. These active compounds were added to soybean oil in different proportions using a simplex-centroid mixture design. Antioxidant activity and oxidative stability of oils were determined before and after 20 days of accelerated oxidation at 60 °C.

CONCLUSION

Results showed that bioactive compounds are effective in maintaining oxidative stability of soybean oil. However, the binary interaction of rosmarinic acid and thymol caused a reduction in antioxidant activity and oxidative stability of soybean oil. Optimum conditions for maximum antioxidant activity and oxidative stability were found to be an equal ternary mixture of carnosol, rosmarinic acid and thymol. © 2016 Society of Chemical Industry.

Improvement of the lipid oxidative stability of soybean oil-inwater emulsion by addition of daraesoon (shoot of Actinidia arguta) and samnamul (shoot of Aruncus dioicus) extract

The effect of 75% ethanol extract of daraesoon and samnamul (200 mg/kg) on the lipid oxidation of soybean oil-in-water (4:6, w/w) emulsion containing iron (5 mg/kg) in dark conditions at 25°C was studied by determining headspace oxygen and hydroperoxide contents. Polyphenol, carotenoid, and chlorophyll contents were also evaluated using spectrophotometry. The headspace oxygen contents were higher and hydroperoxide contents were lower (p<0.05) in the emulsions with added daraesoon and samnamul extracts compared with the control emulsion without the extract. The antioxidant activity of the daraesoon and samnamul extracts in the lipid oxidation of the emulsions was comparable to that of dibutylhydroxytoluene at 200mg/kg. Polyphenols, carotenoids, and chlorophylls were degraded during oxidation of the emulsions, possibly due to a role of the antioxidants. The results suggest that contribution to the improved lipid oxidative stability of the emulsion with added samnamul and daraesoon would be due to polyphenols and pigments, respectively.

Effects of selected herb extracts on iron-catalyzed lipid oxidation in soybean oil-in-water emulsion

Effect of herb extracts on the oil oxidation of an oil-in-water emulsion containing iron was studied. The emulsion comprised tocopherol-stripped soybean oil (40 g), citrate buffer (60 g, pH 4.0), xanthan gum (35mg), and FeSO₄ (0.5mg) with 80% ethanol extracts of rosemary (Rosmarinus officinalis), basil (Ocimum basilicum), peppermint (Mentha piperita), thyme (Thymus vulgaris), or oregano (Origanum vulgare). Hydroperoxide contents and p-anisidine values were significantly (p<0.05) lower in the emulsions with the added herb extracts compared with the control emulsions. The antioxidant activity of the basil and peppermint extracts containing higher proportions of rosmarinic acid was significantly higher (p<0.05) than that of the other herb extracts, but the polyphenol degradation rate was not significantly different. The antioxidant activity of the basil and peppermint extracts showed concentration-dependence within 400 mg/kg. This study suggests that the oxidative stability of oil-inwater emulsion containing iron can be improved by addition of basil or peppermint extract.

Alleviative effects of litchi (Litchi chinensis Sonn.) flower on lipid peroxidation and protein degradation in emulsified pork meatballs

To avoid or retard the lipid peroxidation of meat products, antioxidants are commonly added. Considering the safety and health of additives in meat products, consumers prefer natural antioxidants rather than synthetic ones. Gentisic acid and epicatechin were identified as the major phenolic acid and flavonoid, respectively, of litchi flowers (LFs). The physicochemical properties of pork meatballs with or without dried LF powders (0.5%, 1.0%, and 1.5%, w/w) and tert-butylhydroquinone (TBHQ; 0.01%, w/w) were analyzed during a 4-week frozen storage period. LF and TBHQ decreased (p < 0.05) thiobarbituric acid reactive substance (TBARS) values but increased (p < 0.05) thiol group contents in meatballs. LF added to meatballs improved (p < 0.05) texture and water-holding capacity (centrifugation/purge losses) more than in the control group upon the storage. Although LF powders made meatballs redder and darker (p < 0.05) than the control and TBHQ groups, they did not affect the preference of panelists. The addition of 0.5% LF powders exhibited the best (p < 0.05) overall sensory panel acceptance. LFs may be an effective natural antioxidant to reduce lipid and protein oxidation for frozen cooked meat products.

Comparison of total phenolic contents and antioxidant capacities in mint genotypes used as spices / Baharat olarak kullanılan nane genotiplerinin toplam fenolik içerikleri ve antioksidan kapasitelerinin karşılaştırılması

Objective: Mint (Mentha spp.) genotypes used as spices are cultivated in Turkey and used for different purposes including herbal tea, spices, the cosmetics industry, and are used in folk medicine. While mint species have been used in traditional practices during humanity’s long history, there is limited research on the comparison of their antioxidant capacity and phenolic contents. This aim of the research is to compare antioxidant capacity and phenolic contents in mint clones to determine superior genotypes for herbal and spice usage and cultivation.

Methods: Antioxidant capacity was evaluated by ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC). Total phenolic content in clones were determined by Folin-Ciocalteu method.

Results: Maximum total phenolic content [28.27±3.95 μg gallic acid equivalent (GAE)/g dry weight (DW)] and FRAP activity 577.09±46.02 μmol Trolox equiv/g DW were obtained from Clone 13 (M. spicata), while M. piperita clones were higher for TEAC activity (800.02±1.10 μmol Trolox equiv/g DW). The results were first records for M. villoso nervata. FRAP and TEAC activities selected clones were correlated with total phenolic content (r=0.77; 0.73 respectively).

Conclusion: According to the results, it can be suggested that Clone 13, Clone 5, (M. spicata) Clone 3 and Clone 8 (M. piperita) are more suitable for use as spice, herbal tea, and antioxidant agents. The clones must be selected for commercial cultivation by the grower and they can be used as spices and herbal teas.