Antimicrobial Activity of Nanoencapsulated Essential Oils of Tasmannia lanceolata, Backhousia citriodora and Syzygium anisatum against Weak-Acid Resistant Zygosaccharomyces bailii in Clear Apple Juice

The anti-yeast activity of oil-in-water encapsulated nanoemulsion containing individual or a combination of the three essential oils of Tasmanian pepper leaf (Tasmannia lanceolata), lemon myrtle (Backhousia citriodora), and anise myrtle (Syzygium anisatum) against weak-acid resistant Zygosaccharomyces bailii in clear apple juice was investigated. The effectiveness of the shelf-life extension of Z. bailii-spiked (1 × 103 CFU/mL) clear apple juice was evaluated and compared between natural (essential oils) and synthetic (sodium benzoate) antimicrobial agents. Essential oils showed an immediate reduction in the Z. bailii cell population at day-0 and exerted a fungicidal activity at day-4 of storage, with no further noticeable growth at the end of the experiment (day-28). At lower concentrations, Tasmanian pepper leaf oil of 0.0025% had >6 log CFU/mL at day-12 of storage. For lemon myrtle essential oils, the yeast population reached >6 log CFU/mL at day-24 and day-20 for concentrations of 0.02% and 0.01%, respectively. The fungicidal activity of Tasmanian pepper leaf oil reduced from 0.005% to 0.0025% v/v when mixed at a ratio of 1:1 with anise myrtle oil. The results of the present study suggest that these three native Australian herbs have the potential to be used in the beverage industry by controlling Zygosaccharomyces bailii in clear apple juice products. View Full-Tex

Formulation, characterization, and stability of food grade oil-in-water nanoemulsions of essential oils of Tasmannia lanceolata, Backhousia citriodora and Syzygium anisatum

Oil-in-water nanoemulsions were formulated using sunflower oil mixed with each of the essential oils of Tasmannia lanceolata (Tasmanian pepper leaf [TPL]), Backhousia citriodora (lemon myrtle [LM]) and Syzygium anisatum (anise myrtle [AM]) and stabilized with Tween 80 using ultrasonication. An oil-surfactant ratio of 3:1 was found to produce the lowest emulsion droplet sizes of 96.6 nm for LM, 122.2 nm for AM and 131.8 nm for TPL. Increase in surfactant concentration above 10r resulted in larger droplet sizes, 165.8–2,647.2 nm for LM (radius, r =.82), 153.7–2,573.5 nm for AM (r =.93) and 157.4–2,621.6 nm for TPL (r =.83). Sonication for 3 min produced smaller droplet size; however, sonication for 9 min resulted in increase of droplet size by 1.48, 1.43 and 1.47 times for oils of LM (r =.82), AM (r =.93) and TPL (r =.83), respectively. A positive correlation was found between sonication amplitude (20–50%) and droplet size for nanoemulsions of LM (r =.93), AM (r =.98) and TPL (r =.95). TPL and LM nanoemulsions showed broad- spectrum antimicrobial activities against yeasts and bacteria. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) against weak-acid resistant yeasts were between 0.001–0.003 and 0.002–0.007 mg/ml for nanoemulsion of TPL and between 0.003–0.014 mg/ml and 0.005–0.027 for nanoemulsion of LM, respectively. The stability and antimicrobial activity of TPL and LM essential oil nanoemulsions confirm their potential for application as food preservatives especially in beverage products that are commonly spoiled by weak-acid resistant yeasts. © 2022 The Authors. Journal of Food Safety published by Wiley Periodicals LLC

Investigating the Efficacy of Tasmannia lanceolata Extract in Inactivating Fungi and Prolonging the Shelf Life of Date Fruit

Date palm (Phoenix dactylifera L.) is one of the world’s oldest cultivated plants. Post-harvest losses of date palm due to fungal contamination reached up to 50% of the total production. This study aimed to investigate the potential of the extract of Tasmanian pepper leaf (TPL) and the non-thermal treatment of photosensitization mediated by curcumin in reducing the fungal contamination and enhancing the shelf life of date palm. In the in vivo storage study, the dates were treated with three different concentrations of TPL extract 12.5, 25, and 50 µg/mL and stored at 30 °C. The findings obtained for the treatment with TPL extract exhibited potent antifungal activity against most of the tested fungi, where minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were < 25 µg/mL for polygodial, the bioactive compound in TPL. The shelf life of date palm treated by 50 µg/mL polygodial was extended up to 21 days, thrice as much as the untreated controls. In contrast, a lower concentration of TPL extract (25 µg/mL polygodial) revealed up to a 15-day shelf life extension compared to untreated dates (7 days). The results obtained from the study suggested that using TPL extracts against pathogenic and spoilage fungi occurring in fresh date fruits is a promising treatment for the shelf life extension of fresh date fruits at room temperatur

Betalain rich functional extract with reduced salts and nitrate content from red beetroot (Beta vulgaris L.) using membrane separation technology

An initial laboratory-scale evaluation of separation characteristics of membranes with nominal molecular weight cut-offs (NMWCO) ranging from 30 kD down to 0.5 kD indicated effective separation of betalains in the 0.5 kD region. Subsequent pilot-level trials using 1 kD, loose reverse osmosis (LRO) and reverse osmosis (RO) spiral-wound membranes showed LRO membrane to be very efficient with up to 96% salt and 47% other dissolved solids removed while retaining majority of the pigment (∼98%) in the betalain rich extract (BRE). The total betalain content in the BRE increased up to 46%, the highest recovery reported so far at pilot scale level. Interestingly, more than 95% of the nitrates were removed from the BRE after the three diafiltrations. These studies indicate that membrane technology is the most efficient technique to produce BRE with highly reduced amounts of salts and nitrate content

The effect of photosensitization mediated by curcumin on storage life of fresh date (Phoenix dactylifera L.) fruit

The effect of photosensitization mediated by curcumin (CUR) in sanitizing the fresh date fruit surface was investigated. Approximately 3-4 mu l CUR solution ranging from 1000 to 1800 mu M was sprayed on the date surface, followed by irradiation using blue light at 420 nm for 10 and 15 min at light dosages of 180 J/cm(2) and 270 J/cm(2) respectively. After irradiation, the date was stored at 4 degrees C and 30 degrees C until fungi was visually observed. The combination of CUR and light resulted in significant (p < 0.05) extension of the shelf life and quality of fresh date. The shelf life of date fruit photosensitized by 1400 mu M CUR for 10 min and stored at 30 degrees C lasted for 14 days in comparison to the 7 days for the control, while date stored at 4 degrees C lasted 98 days for the photosensitized fruit compared to the control of 28 days under the same conditions. In addition, no changes in physico-chemical characteristics were observed after treatment. The sanitization treatment of photosensitization mediated by CUR indicated a promising strategy in extending the shelf life of fresh date fruit. Clean and green technologies that are environmentally friendly like photosensitization are preferred by consumers to the synthetic chemicals used in conventional practices for sanitizing food

“Move n’ Learn” A prototype mobile application for museums.

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Γεωπληροφορική

Effect of solid-state fermented and enzyme-supplemented lupins on performance and ileal amino acid digestibility in broiler chickens

Context: The importance of lupin in animal nutrition has increased over the years due to its moderate protein content and relative availability. Low inclusion rate in broiler diet has been associated with the presence of antinutritional factors. The established beneficial effect of fermentation as a processing strategy and dietary enzyme use in improving the nutritional value of legumes such as lupins, thus, necessitated this study.Aims: This study determined the effect of solid-state fermented lupin (SSFLP) and enzyme-supplemented lupin (LP) on the performance and ileal amino acid digestibility in broiler chickens.Methods: In Experiment 1 (performance trial), a total of 300 day-old Ross 308 male broiler chicks were distributed into six dietary treatments, with five replicates of 10 birds each. Diet 1 was based on a corn–soybean meal (SBM), Diets 2 and 3 contained 250 g/kg LP and 250 g/kg SSFLP respectively. Diet 4 contained 250 g/kg LP + phytase (PHY). Diet 5 contained 250 g/kg LP + xylanase (XYL). Diet 6 contained 250 g/kg LP + PHY + XYL. PHY at 500 phytase units (FTU)/kg and XYL at 1000 units/kg were added to the respective diets. In Experiment 2 (digestibility trial), a total of 240 21-day-old Ross 308 male broiler chicks was assigned to six dietary treatments with five replicate cages of eight birds each. Diet 1 was based on SBM, Diets 2 and 3 contained 650 g/kg LP and 650 g/kg SSFLP respectively. Diet 4 contained 650 g/kg LP + PHY. Diet 5 contained 650 g/kg LP + XYL. Diet 6 contained 650 g/kg LP + PHY + XYL.Key results: Dietary inclusion of SBM and LP + PHY enhanced broiler performance from 1 to 21 days. PHY- supplemented LP diet improved birds’ bodyweight gain and feed intake compared with the rest of the LP diets. Dietary inclusion of LP + PHY + XYL improved the apparent ileal digestibility (AID) of some amino acids (AA). SSF of LP had no effect on the AA contents, lowered AA digestibility and depressed weight gain in the birds. Although SSFLP diet did not improve performance, it effectively increased phosphorus (P) retention in broiler chickens. Feeding SSFLP and enzyme-supplemented LP diets enhanced the AID of calcium and P, as well as calcium retention.Conclusions: Adding supplemental PHY to LP diet enhanced broiler performance, as indicated by the BWG and FI of these birds, which were significantly higher than those of birds fed on other LP-based diets and comparable with those of birds fed on the SBM diet from 1 to 21 days. Although the SSFLP diet did not improve broiler performance, it was effective in increasing P retention when compared with LP diets. The inclusion of LP + PHY + XYL diet improved the AID of amino acids.Implications: SSFLP is a promising feed ingredient and can have a potential application in feed formulation. However, further studies are still needed to be able to clearly understand its effect at a high inclusion level on the performance and ileal amino acid digestibility in broiler chickens. The development of cocktail inoculants to target all ANFs in lupins will definitely open a new window for the poultry feed industry

Formulation, characterisation and antibacterial activity of lemon myrtle and anise myrtle essential oil in water nanoemulsion

This study focussed on the formulation, characterisation of lemon myrtle (LM) and anise myrtle (AM) essential oil (EO) in water nanoemulsion and their antibacterial activity. The required hydrophilic lipophilic balance (rHLB) value of LM EO and AM EO was 14 and 12, respectively. The Central Composite Rotatable Design (CCRD) model produces the smallest droplet size and polydispersity index (PDI) for LMEO (d ≈ 16.07 nm; PDI ≈ 0.209) and AMEO (d ≈ 30.23 nm; PDI ≈ 0.216) at 1% EO and 10% surfactant mixture (Smix) ratio using ultrasonication for 5 min. Whereas, increased in EO, decrease in Smix concentrations and ultrasonication time produces higher droplet size of nanoemulsions. LMEO (LM-15, LM-17) nanoemulsions was clear and transparent compared to AMEO (AM-15, AM-17). All the selected nanoemulsions showed good stability at 4, 25 and 40 °C during storage, except LM-15 at 40 °C. LMEO nanoemulsion showed enhanced antibacterial activity compared to LMEO alone (P

Bioactive properties of mushroom (Agaricus bisporus) stipe extracts

The antibacterial activity and total phenolic (TP) content of Agaricus bisporus stipes were assessed using solvent and water extracts to determine its bioactivity. Extraction methods included accelerated solvent extraction (ASE) and hot water followed by membrane concentration. Water extract from ASE had the highest TP of 1.08 gallic acid equivalents (GAE)/g dry weight (DW) followed by ethanol at 0.61mg GAE/g DW and 0.11mg GAE/g DW for acetone. Acetone extracts inhibited Escherichia coli and Staphylococcus aureus at less than 50%; ethanol inhibited E.coli at 61.9% and S.aureus at 56.6%; and ASE water inhibited E.coli at 78.6% and S.aureus at 65.4%. The TP content of membrane concentrated extract of mushroom was 17mg GAE in 100mL. Membrane concentrated water extracts had a higher percentage inhibition on S.aureus than E.coli. Overall, the results were promising for further application of mushroom stipe extracts as a functional food additive. Practical Applications: Mushrooms are known for their health benefits and have been identified as a good source of nutrients. The highly perishable nature of mushrooms warrants further processing and preservation to minimize losses along the supply chain. This study explores the possibility of adding value to mushroom stipes, a by-product of the fresh mushroom industry. The extracts assessed indicate the antibacterial activity and phenolic content, and the potential of using these extracts as functional ingredients in the food industry. This study provides valuable information to the scientific community and to the industries developing novel ingredients to meet the market demand for natural food additives