Stability enhancement of garlic essential oil using new opopanax gum/gelatin nanofibres

Opopanax gum/gelatin nanofibre was produced by the electrospinning method, and the efficiency of this new technique for encapsulation of garlic essential oil was investigated. Fourier-transform infrared spectroscopy results showed the physical and weak interactions between opopanax gum and gelatin, as well as the improvement of their thermal stability in the nanofibres structure. Incorporating 10% garlic essential oil based on biopolymer weight in nanofibres was considered the best percentage. The results confirmed the presence of garlic essential oil in the nanofibres and the improvement of its thermal stability by entrapment to the nanofibre structure. The data of analysis of the stability of garlic essential oil in the forms of free and encapsulated conditions showed that its stability increased at 25 °C from 20 days to more than 60 days. It indicated the efficiency of opopanax gum/gelatin nanofibres as an applicable coating material for stability enhancement of essential oils.     

Prebiotic properties of xylooligosaccharide extracted from sugarcane wastes (pith and rind): a comparative study

Wastes from agricultural industry are often disposed. Nevertheless, these wastes contain nutraceuticals and functional compounds. Xylooligosaccharide (XOS) was extracted from two sugarcane wastes (SW); rind (SR) and pith (SP), and the prebiotic properties of both XOS were examined. SR and SP had different mixture of XOS and were resistant towards α-amylase and gastric juice digestion in vitro. Although the growth of Lactobacillus casei Shirota (LcS) and Bifidobacterium animalis subsp. Lactis ATCC® 700541™ increased significantly in both XOS after 48 h of incubation, XOS from SR showed better enrichment of probiotics growth. Both XOS were found to be more fermentable by LcS and acetic acid was the predominant end product of the fermentation. Since XOS composition was different between SR and SP and such difference can affect their prebiotic properties, it is important to choose the appropriate parts of SW to extract XOS with high fermentable properties and obtain the best synbiotics combination.     

Physicochemical stability of antilisterial proteins from P. polymyxa Kp10 as potential food biopreservative

Listeria monocytogenes has continuously become a significant threat to consumers worldwide. The use of chemical-derived preservatives that are commonly associated with safety and nutritional issues has prompted the use of natural-based preservatives as a better alternative. Many bacterial strains including Paenibacillus polymyxa Kp10 have been reported to produce various antimicrobial proteins and compounds that are considered more natural. However, their stability in various physicochemical conditions should be examined before being applied in various types of food. In this study, the stability of four previously identified antilisterial proteins in P. polymyxa Kp10 upon exposure to several physicochemical conditions was examined. More than 80% residual antilisterial activity is conserved upon heat and proteinase K treatment. But, sensitivity to 24 h trypsin digestion has been observed. P1 and P2 proteins (histone-like DNA binding proteins HU) were sensitive to alkaline pH (pH 10-12) as compared with other proteins. More than 70% and 97% residual antilisterial activity were recovered after incubation in raw beef homogenates and simulated meat gravy model, respectively. However, the antilisterial activity of most proteins was highly compromised in chicken and salmon meat homogenates, and UHT cow milk. Inoculation of these proteins into Listeria-contaminated simulated meat gravy showed that all proteins exerted a bactericidal action against L. monocytogenes. P1 and P2 shared almost similar antilisterial activity rates, while P4 was the most potent antilisterial protein. The findings in this study could provide important preliminary data for future applications of these proteins as preservative in food products especially beef-based meat products.     

Termites as human foods—A comprehensive review

Global food production is anticipated to rise along with the growth of the global population. As a result, creative solutions must be devised to ensure that everyone has access to nutritious, affordable, and safe food. Consequently, including insects in diets has the potential to improve global food and nutrition security. This paper aims to share recent findings by covering edible termites as the main aspect, from their consumption record until consumer acceptance. A total of 53 termite species are reported as edible ones and distributed in 6 biogeographic realms. Generally, termites have a nutrient composition that is suitable for human consumption, and cooked termites are a better dietary choice than their raw counterparts. Besides, increasing customer interest in eating termite-based food can be achieved by making it more palatable and tastier through various cooking processes, that is, boiling, frying, grilling, roasting, smoking, and sun-drying. Moreover, edible termites can also be used as a new source of medication by exhibiting antimicrobial activity. Regarding their advantages, it is strongly encouraged to implement a seminatural rearing system to sustain the supply of edible termites. Overall, this paper makes it evident that termites are an important natural resource for food or medicine. Hence, the long-term objective is to stimulate scientific inquiry into the potential of edible insects as an answer to the problem of global food security.     

Phytochemicals of ethanolic extract and essential oil of Persicaria hydropiper and their potential as antibacterial agents for food packaging polylactic acid film

This study aims to determine phytochemicals and antibacterial activity of ethanolic extract and essential oil of Persicaria hydropiper, and their potential as antibacterial agents in polylactic acid (PLA) film. The yield of ethanolic extract and essential oil were 11.02 and 0.70%, respectively. Chlorogenic acid, ferulic acid, rutin, myricetin and quercetin were detected as major components in the P. hydropiper ethanolic extract, while dodecanal, caryophyllene, caryophyllene oxide, decanal, α‐caryophyllene, citronellol, heptadecanal, linalool and phytol were detected in the P. hydropiper essential oil. Based on the disc diffusion assay, both ethanolic extract and essential oil of P. hydropiper possessed antibacterial activity against bacteria Staphylococcus aureus only at different concentrations, with minimum inhibitory concentration values: 0.625 and 5 mg/ml, respectively; and minimum bactericidal concentration values: 5 and 40 mg/ml, respectively. However, they found to show antibacterial activity against three bacteria S. aureus, Escherichia coli and Salmonella Typhimurium at different concentrations and time using time‐kill kinetics assay. Incorporation of ethanolic extract and essential oil in PLA film also exhibited an antibacterial effect against S. aureus. Our findings confirmed the potential use of both P. hydropiper ethanolic extract and essential oil as antibacterial agents in biodegradable PLA film.     

Physicochemical properties of pre-treated cuttlebone powder and its potential as an alternative calcium source

This study was aimed to investigate the potential use of pre-treated cuttlebone powder (CBP) as an alternative calcium source by evaluating the physicochemical properties of CBP pre-treated with distilled water (CBP1), 1% acetic acid (CBP2), and 2% sodium hydroxide (NaOH) solutions (CBP3). Proximate analysis revealed ash as the major component of all samples. The presence of phenols, flavonoids, alkaloids, and glycosides were detected but tannins appeared to be absent in cuttlebones. Mineral analysis indicated that CBP was rich in calcium, which means the material may be considered as a potential calcium source for food products or calcium supplements. The bulk density of CBP2 was significantly lower (p < .05) than those of CBP1 and CBP3, and the water holding capacity (WHC) of CBP1 was significantly higher (p < .05) than those of CBP2 and CBP3. The high bulk density, water and oil holding capacities of CBP demonstrated its potential use as a functional food ingredient.     

Miscibility of oligomeric poly(dimethyl siloxanes) with long-chain unbranched alkanes: 2. Unsymmetrical cloud point curves

Previously obtained cloud point curves for mixtures of oligomeric poly(dimethyl siloxanes) (weight fraction W₁) with oligomeric polyethylenes have been supplemented by the use of samples of higher molecular weight. Initial flat regions at low-medium W₁ as well as a slight shoulder at extremely high W₁ are now considered to be due to crystallization, since the temperatures at which they occur are the melting points of the oligoethylenes. The actual cloud point curves were of an unsymmetrical dome shape, the form of which could not be simulated by using a concentration-independent interaction parameter g in the Flory-Huggins equation. However, spinodals calculated by assuming a quadratic dependence of g on composition were of the same shape as the experimental cloud point curves. The critical compositions calculated on this basis were also close to the experimental ones.