High Throughput Screening for Bioactive Volatile Compounds and Polyphenols from Almond (Prunus amygdalus) Gum: Assessment of Their Antioxidant and Antibacterial Activities

High Throughput Screening for Bioactive Components of Berberis baluchistanica Ahrendt Root and Their Functional Potential Assessment

Berberis baluchistanica Ahrendt is a medicinal plant potentially known for the treatment of different diseases. The bioactive, antioxidant, nutritional components, and antimicrobial properties of crude ethanolic root extract of Berberis baluchistanica were evaluated in this study. The extract was analyzed for total phenolic, flavonoid, DPPH (2, 2-diphenyl-1-picryl-hydrazyl) scavenging ability, FRAP (ferric reducing antioxidant power), nutritional, and antimicrobial potentials. The alkaloids, tannins, cardiac glycosides, anthraquinones, coumarin, saponins, phenolics, flavonoids, steroids, and terpenoids were confirmed. The extract possessed DPPH radical inhibition with the IC50 of 1.125 mg/mL and FRAP % reduction activity with IC50 (0.912 mg/mL). Total phenolic $19.897\pm 4.8141\text{mg}$ GAE/g and flavonoid $12.9876\pm 0.8388\text{mg}$ QE/g contents were confirmed in the root. The extracts exhibit good antibacterial activity against a broad spectrum of food borne pathogens Pseudomonas aeruginosa, Salmonella typhi, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. The highest inhibitory activity was against Escherichia coli $23.30\pm 1.16\text{mm}$ and lowest against Klebsiella pneumoniae $7\pm 0.01\text{mm}$ . Furthermore, the presence of various phytochemical constituents (plant secondary metabolites) was also confirmed with gas chromatography and mass spectroscopy analysis. Results disclosed the occurrence of more than 70 compounds possessing various medicinal properties supporting the traditional uses of root of Berberis baluchistanica in various medical complications indigenously.

Biochemical and Histological Insights into the Interaction Between the Canker Pathogen Neofusicoccum parvum and Prunus dulcis

The number of reports associated with wood dieback caused by fungi in the Botryosphaeriaceae in numerous perennial crops worldwide has significantly increased in the past years. In this study, we investigated the interactions between the canker pathogen Neofusicoccum parvum and the almond tree host (Prunus dulcis), with an emphasis on varietal resistance and host response at the cell wall biochemical and histological levels. Plant bioassays in a shaded house showed that among the four commonly planted commercial almond cultivars ('Butte', 'Carmel', 'Monterey', and 'Nonpareil'), there was no significant varietal difference with respect to resistance to the pathogen. Gummosis was triggered only by fungal infection, not by wounding. A two-dimensional nuclear magnetic resonance and liquid chromatography determination of cell wall polymers showed that infected almond trees differed significantly in their glycosyl and lignin composition compared with healthy, noninfected trees. Response to fungal infection involved a significant increase in lignin, a decrease in glucans, and an overall enrichment in other carbohydrates with a profile similar to those observed in gums. Histological observations revealed the presence of guaiacyl-rich cell wall reinforcements. Confocal microscopy suggested that N. parvum colonized mainly the lumina of xylem vessels and parenchyma cells, and to a lesser extent the gum ducts. We discuss the relevance of these findings in the context of the compartmentalization of decay in trees model in almond and its potential involvement in the vulnerability of the host toward fungal wood canker diseases.

Enhanced Pharmaceutically Active Compounds Productivity from Streptomyces SUK 25: Optimization, Characterization, Mechanism and Techno-Economic Analysis

The present research aimed to enhance the pharmaceutically active compounds’ (PhACs’) productivity from Streptomyces SUK 25 in submerged fermentation using response surface methodology (RSM) as a tool for optimization. Besides, the characteristics and mechanism of PhACs against methicillin-resistant Staphylococcus aureus were determined. Further, the techno-economic analysis of PhACs production was estimated. The independent factors include the following: incubation time, pH, temperature, shaker rotation speed, the concentration of glucose, mannitol, and asparagine, although the responses were the dry weight of crude extracts, minimum inhibitory concentration, and inhibition zone and were determined by RSM. The PhACs were characterized using GC-MS and FTIR, while the mechanism of action was determined using gene ontology extracted from DNA microarray data. The results revealed that the best operating parameters for the dry mass crude extracts production were 8.20 mg/L, the minimum inhibitory concentrations (MIC) value was 8.00 µg/mL, and an inhibition zone of 17.60 mm was determined after 12 days, pH 7, temperature 28 °C, shaker rotation speed 120 rpm, 1 g glucose /L, 3 g mannitol/L, and 0.5 g asparagine/L with R² coefficient value of 0.70. The GC-MS and FTIR spectra confirmed the presence of 21 PhACs, and several functional groups were detected. The gene ontology revealed that 485 genes were upregulated and nine genes were downregulated. The specific and annual operation cost of the production of PhACs was U.S. Dollar (U.S.D) 48.61 per 100 mg compared to U.S.D 164.3/100 mg of the market price, indicating that it is economically cheaper than that at the market price.

Microencapsulation of probiotics in finger millet milk complex to improve encapsulation efficiency and viability

This study aimed to assess the effectiveness of finger millet milk complex (almond gum with maltodextrin) to encapsulate the isolated Lactobacillus strains. The wall materials were optimized based on its encapsulation efficiency, antioxidant activity, total phenol content and encapsulation yield. The strains were spray-dried at the optimized condition: 120 °C inlet temperature, maltodextrin 30% and almond gum 1.5%. Survival count of microencapsulated Lactobacillus plantarum RS09 and RS23 strains were 7.91 and 7.83 CFU/g respectively. Viability of microencapsulated strains and free cells under low pH, bile salt, simulated gastric juice and intestinal juice were assessed. Strain RS09 exhibited the highest viable count. Addition of almond gum and finger millet milk increased the phenolic content and offered a protective effect to the strains during spray drying. Results also showed that the powders were amorphous with partial irregularities and a smooth surface with less dents. Hence, they could be used as potential encapsulating agents during spray drying.

The effect of resin coating on the quality characteristics of chicken eggs during storage

In this study, after washing, changes in the quality characteristics of chicken eggs coated with apricot, almond, and sour cherry tree resins were examined during two different temperatures (4 °C and 22 °C) storage for 60 days. While air cell height, weight loss, albumen and yolk pH and a* (redness) values increased in all samples during storage, Haugh unit, albumen and yolk index, shell fracture and vitelline membrane strength, albumen and yolk L* (lightness) and b* (yellowness) values decreased (P < 0.05). The lowest weight loss (0.54 g) and air cell height (2.89 mm), highest Haugh unit (73.95 HU), albumen index (8.81%), and yolk index (40.37%) were found in the samples coated with sour cherry wood resin stored at 4 °C. The shell breakage and vitelline membrane strength of the coated samples were determined to be higher than the control samples and the samples stored after washing. Higher weight loss, air cell height, and pH values, while lower Haugh unit, Albumen and yolk index were found in samples stored at 22 °C (P < 0.05). At the end of storage, the maximum increase in the counts of total aerobic mesophilic and psychrophilic bacteria was found in the albumin and egg yolk of washed samples stored at ambient temperature. As a result, the coating materials prepared with the resin of apricot, almond, and sour cherry trees were suitable for eggshell's shelf life extension. PRACTICAL APPLICATION: The consumers demand the eggs be in their freshest condition, but the currently available storage conditions are not sufficient to maintain freshness in many regions of Turkey. The physical, chemical and, microbiological qualities of the eggs coated with wood resins were determined to be superior compared to other samples. Because resins have good barrier properties, it is recommended to conduct extensive studies on their applicability in different products.

Larvicidal, Histopathological, Antibacterial Activity of Indigenous Fungus Penicillium sp. Against Aedes aegypti L and Culex quinquefasciatus (Say) (Diptera: Culicidae) and Its Acetylcholinesterase Inhibition and Toxicity Assessment of Zebrafish (Danio rerio)

Fungal metabolites are considered to be most efficient tools to overcome the issues related to insecticide resistance and environmental pollution. The present study focus on the evaluation of the mosquito larvicidal efficacy of metabolites of seven indigenous fungal isolates (Penicillium sp. Aspergillus niger, A. flavus, A. parasiticus, Rhizopus sp. Mucor sp. and Aspergillus sp.) on the larvae of Aedes aegypti and Culex quinquefasciatus under the laboratory condition. The preliminary screening of the isolate, Penicillium sp. showed better larvicidal effect when compared to other fungi. The fungus was grown on Potato Dextrose Broth (PDB) in the laboratory (at 25°C) and maintained in the relative humidity (at 76 ± 4% for 15 days). Larvicidal potency of mycelial ethyl acetate extract (MEAE) of Penicillium sp. was performed against 1st to 4th instars larvae of Ae. aegypti and Cx. quinquefasciatus using four different concentrations (100, 200, 300, and 500 μg/ml) that showed better larval mortality values (μg/ml) of LC50 = 6.554, 5.487, 6.874, 6.892, and the LC90 = 11.486, 10.366, 12.879, 13.865 for Ae. aegypti and LC50 = 7.000, 13.943, 18.129, 25.212 and the LC90 = 12.541, 23.761, 30.923, 41.696 for Cx. quinquefasciatus. Exposure of metabolite to larvae resulted in behavior changes i.e., excitation, up and down with aggressive movement, anal papillae biting behavior. Further, the larvae treated with Penicillium sp. metabolite exhibited significant reduction in the levels of acetylcholinesterase. The 4th instar mosquito larvae treated with the 500 μg/ml mycelia extract showed severe histological damages. During the antibacterial analysis of Penicillium sp.- mycelium the maximum growth inhibition zone was recorded in Shigella dysenteriae (31.2 mm) and Klebsiella pneumoniae (31.1 mm) followed by others. In addition, to check the toxicity of Penicillium sp. MEAE against embryos of Zebrafish, a model system, using different concentrations of metabolites (1.0, 0.5, 0.125 mg/ml, 30, 3.0, and 0.5 μg/ml) and life-stage parameters were observed at 124 hpf. Furthermore, the Fourier Transformed Infrared and GCMS spectrum analysis of mycelium reflected several chemical compounds. The outcome of the study clearly shows that Penicillium sp. metabolites could serve as an ideal eco-friendly, single-step and inexpensive source for the control of Ae. aegypti and Cx. quinquefasciatus larvae.

Essential oils as natural preservatives for bakery products: Understanding the mechanisms of action, recent findings, and applications

Bakery products, as an important part of a healthy diet, are characterized by their limited shelf-life. Microbiological spoilage of these products not only affects the quality characteristics and result in the economic loss but also threatens consumer's health. Incorporation of chemical preservatives, as one of the most conventional preserving techniques, lost its popularity due to the increasing consumer's health awareness. Therefore, the bakery industry is seeking alternatives to harmful antimicrobial agents that can be accepted by health-conscious customers. In this regard, essential oils have been previously used as either a part of product ingredient or a part of the packaging system. Therefore, the antimicrobial aspect of essential oils and their ability in delaying the microbiological spoilage of bakery products have been reviewed. Several types of essential oils, including thyme, cinnamon, oregano, and lemongrass, can inhibit the growth of harmful microorganisms in bakery products, resulting in a product with extended shelf-life and enhanced safety. Research revealed that several bioactive compounds are involved in the antimicrobial activity of essential oils. However, some limitations, such as the possible negative effects of essential oils on sensory parameters, may limit their applications, especially in high concentrations. In this case, they can be used in combination with other preservation techniques such as using appropriate packaging materials. Further research regarding the commercial production of the bakery products formulated with essential oils is required in this area.