scholarly journals Electrospraying of zein for the preparation of micro/nano-particles loaded with sarcopoterium spinosum extract

2019 ◽  
Vol 8 (3) ◽  
pp. 591-596
Keyword(s):  
Bioactive Compounds ◽  
Folk Medicine ◽  
Antimicrobial Properties ◽  
Weight Ratio ◽  
Natural Compounds ◽  
Storage Conditions ◽  
Nano Particles ◽  
Particle Structure ◽  
Sarcopoterium Spinosum ◽  
Processing And Storage

Natural compounds that are isolated from various plant species have been the focus of folk medicine due to their bioactivities. Pharmaceutical, food and cosmetic industries also utilize these natural compounds with antioxidant and antimicrobial properties. Harsh processing and storage conditions causing loss of their bioactivities limit their applications. Therefore, biopolymeric carrier systems are required to preserve the natural bioactive compounds stability. Sarcopoterium spinosum is used in folkloric medicine for curing diabetes, gastrointestinal illnesses, cancer and pain. In this study, both solution and process parameters for electrospraying technique were investigated to encapsulate S. spinosum extract including natural bioactive compounds in zein particles. The best results were observed in 5% (w/v) of zein concentration in 70% aqueous ethanol. 0.3 ml/hour flow rate and 14 kV applied voltage were used in order to obtain narrow size distributionorbicular and smooth particle structure. The best mixture of S. spinosum extract and zein was achieved at weight ratio of 1:5. The zein microparticles with extract showed remarkable antioxidant activity.

scholarly journals An Investigation of Moroccan Vinegars: Their Physicochemical Properties and Antioxidant and Antibacterial Activities

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Driss Ousaaid ◽  
Hamada Imtara ◽  
Hassan Laaroussi ◽  
Badiaa Lyoussi ◽  
Ilham Elarabi
Keyword(s):  
Physicochemical Properties ◽  
Bioactive Compounds ◽  
Antibacterial Activities ◽  
Storage Conditions ◽  
Production Methods ◽  
Maximum Value ◽  
Processing And Storage ◽  
And Storage ◽  
Excellent Source

Vinegar is a natural product rich in bioactive compounds such as phenols, flavonoids, and organic acids. Several factors affect the quality of vinegars such as apple origin, environmental conditions, production methods, processing, and storage conditions. We investigated the quality of apple vinegars as well as their physicochemical properties and the antioxidant and antibacterial activities of vinegars collected from different areas in Morocco. For physicochemical properties, the outcomes showed the following values: pH (3.18–3.83), electrical conductivity (2.11–2.90), acidity (0.24–5.6), Brix (3.25–6), and density (1.0123–1.0233). The polyphenols content of samples was 68.91 mg AG/100 mL in sample S6 as the minimum value and 147.54 mg AG/100 mL in sample S2 as the maximum value. The best ability to scavenge the DPPH radical was observed in sample S3 (IC50 = 0.45 ± 0.013 µL/mL). Sample S2 showed moderate antibacterial effect against microorganisms tested with MICs ranging from 0.78 µL/mL to 1.125 µL/mL and with a diameter of inhibition ranging from 15.65 mm to 27.65 mm. In addition, a strong correlation was observed between the antibacterial activity of vinegars and physicochemical parameters (pH and total acidity). These outcomes have shown that our vinegar samples are an excellent source of bioactive compounds with potent antioxidant and antibacterial potentials.

Electron holography of catalysts

1995 ◽  
Vol 53 ◽  
pp. 416-417
Author(s):  
A. K. Datye ◽  
D. S. Kalakkad ◽  
L. F. Allard ◽  
E. Völkl
Keyword(s):  
Heterogeneous Catalysts ◽  
High Surface ◽  
High Surface Area ◽  
Atomic Scale ◽  
Nano Particles ◽  
Phase Image ◽  
Electron Holography ◽  
Specimen Thickness ◽  
Phase Information ◽  
Particle Structure

The active phase in heterogeneous catalysts consists of nanometer-sized metal or oxide particles dispersed within the tortuous pore structure of a high surface area matrix. Such catalysts are extensively used for controlling emissions from automobile exhausts or in industrial processes such as the refining of crude oil to produce gasoline. The morphology of these nano-particles is of great interest to catalytic chemists since it affects the activity and selectivity for a class of reactions known as structure-sensitive reactions. In this paper, we describe some of the challenges in the study of heterogeneous catalysts, and provide examples of how electron holography can help in extracting details of particle structure and morphology on an atomic scale.Conventional high-resolution TEM imaging methods permit the image intensity to be recorded, but the phase information in the complex image wave is lost. However, it is the phase information which is sensitive at the atomic scale to changes in specimen thickness and composition, and thus analysis of the phase image can yield important information on morphological details at the nanometer level.

Extraction of Essential Oils from Medicinal Plants and their Utilization as Food Antioxidants

2020 ◽  
Vol 26 (5) ◽  
pp. 519-541 ◽  
Author(s):  
Giovanna Ferrentino ◽  
Ksenia Morozova ◽  
Christine Horn ◽  
Matteo Scampicchio
Keyword(s):  
Chemical Composition ◽  
Medicinal Plants ◽  
Beneficial Effect ◽  
Essential Oils ◽  
Bioactive Compounds ◽  
Antimicrobial Properties ◽  
Food Products ◽  
Human Diseases ◽  
Present Review ◽  
Green Technologies

Background: The use of essential oils is receiving increasing attention worldwide, as these oils are good sources of several bioactive compounds. Nowadays essential oils are preferred over synthetic preservatives thanks to their antioxidant and antimicrobial properties. Several studies highlight the beneficial effect of essential oils extracted from medicinal plants to cure human diseases such as hypertension, diabetes, or obesity. However, to preserve their bioactivity, the use of appropriate extraction technologies is required. Method: The present review aims to describe the studies published so far on the essential oils focusing on their sources and chemical composition, the technologies used for their recovery and their application as antioxidants in food products. Results: The review has been structured in three parts. In the first part, the main compounds present in essential oils extracted from medicinal plants have been listed and described. In the second part, the most important technologies used for extraction and distillation, have been presented. In detail, conventional methods have been described and compared with innovative and green technologies. Finally, in the last part, the studies related to the application of essential oils as antioxidants in food products have been reviewed and the main findings discussed in detail. Conclusions: In summary, an overview of the aforementioned subjects is presented by discussing the results of the most recent published studies.

scholarly journals The Influence of Temperature, Storage Conditions, pH, and Ionic Strength on the Antioxidant Activity and Color Parameters of Rowan Berry Extracts

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3786
Author(s):  
Elena Cristea ◽  
Aliona Ghendov-Mosanu ◽  
Antoanela Patras ◽  
Carmen Socaciu ◽  
Adela Pintea ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Ionic Strength ◽  
Organic Acids ◽  
Bioactive Compounds ◽  
Acid Methyl Ester ◽  
Storage Conditions ◽  
Raw Material ◽  
Thermal Treatments ◽  
Spectrophotometric Methods ◽  
Berry Extracts

Recent trends in the food industry combined with novel methods in agriculture could transform rowan into a valuable raw material with potential technological applications. Thus, the aim of this research was to investigate the content of bioactive compounds in its fruits and to assess the color and antioxidant stability of the extracts prepared from such fruits during various thermal treatments and at different pH and ionic strength values. Various spectrophotometric methods, HPLC, and capillary electrophoresis were used to quantify the concentrations of bioactive compounds—polyphenols, carotenoids, organic acids, and to assess antioxidant activity and color. The results show that rowan berries contain circa 1.34–1.47 g/100 g of polyphenols among which include catechin, epicatechin, ferulic acid methyl ester, procyanidin B1, etc.; ca 21.65 mg/100 g of carotenoids including zeaxanthin, β-cryptoxanthin, all-trans-β-carotene, and various organic acids such as malic, citric, and succinic, which result in a high antioxidant activity of 5.8 mmol TE/100 g. Results also showed that antioxidant activity exhibited high stability when the extract was subjected to various thermal treatments, pHs, and ionic strengths, while color was mainly impacted negatively when a temperature of 100 °C was employed. This data confirms the technological potential of this traditional, yet often overlooked species.

scholarly journals Determination of the Chemical Composition of Tea by Chromatographic Methods: A Review

2015 ◽  
Vol 4 (3) ◽  
pp. 56 ◽  
Author(s):  
Alexandr Ya Yashin ◽  
Boris V. Nemzer ◽  
Emilie Combet ◽  
Yakov I. Yashin
Keyword(s):  
Chemical Composition ◽  
Volatile Compounds ◽  
Black Tea ◽  
Storage Conditions ◽  
Organoleptic Evaluation ◽  
Chromatographic Methods ◽  
Tea Quality ◽  
Processing And Storage ◽  
And Storage

<p>Despite the fact that mankind has been drinking tea for more than 5000 years, its chemical composition has been studied only in recent decades. These studies are primarily carried out using chromatographic methods. This review summarizes the latest information regarding the chemical composition of different tea grades by different chromatographic methods, which has not previously been reviewed in the same scope. Over the last 40 years, the qualitative and quantitative analyses of high volatile compounds were determined by GC and GC/MS. The main components responsible for aroma of green and black tea were revealed, and the low volatile compounds basically were determined by HPLC and LC/MS methods. Most studies focusing on the determination of catechins and caffeine in various teas (green, oolong, black and pu-erh) involved HPLC analysis.</p> <p>Knowledge of tea chemical composition helps in assessing its quality on the one hand, and helps to monitor and manage its growing, processing, and storage conditions on the other. In particular, this knowledge has enabled to establish the relationships between the chemical composition of tea and its properties by identifying the tea constituents which determine its aroma and taste. Therefore, assessment of tea quality does not only rely on subjective organoleptic evaluation, but also on objective physical and chemical methods, with extra determination of tea components most beneficial to human health. With this knowledge, the nutritional value of tea may be increased, and tea quality improved by providing via optimization of the growing, processing, and storage conditions.</p>

scholarly journals In-Vitro Activity of Nano Fluconazole and Conventional Flucon-azole against Clinically Important Dermatophytes

2020 ◽  
Author(s):  
Najmossadat MUSAVI BAFRUI ◽  
Seyed Jamal HASHEMI HAZAVEH ◽  
Mansour BAYAT
Keyword(s):  
Zeta Potential ◽  
Fungal Infections ◽  
Antifungal Susceptibility ◽  
Nano Particles ◽  
Medical Sciences ◽  
Particle Structure ◽  
Epidermophyton Floccosum ◽  
Dermatophyte Species ◽  
Better Than

Background: Dermatophytosis is one of the most common fungal infections in humans. Antifungals such as fluconazole are effectively used for treating dermatophytosis; however, drug resistance was observed in many cases. Therefore, a newer treatment strategy is essential. Methods: This study (Conducted in the Laboratory of the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran in 2018) evaluated the antifungal susceptibility of nano fluconazole compared to conventional fluconazole on dermatophyte isolates using CLSI M38-A2guidelines. Dermatophyte species isolated from clinical cases of dermatophytosis were identified using PCR sequencing techniques. Zeta potential and size of the nano particles containing fluconazole were measured; scanning electron microscope (SEM) was used to determine nano particle structure. Results: The size of liposomal fluconazole obtained was 88.9  12.14 nm with –20.12  3.8 mV for zeta potential. The encapsulation rate for fluconazole was 75.1  4.2%. MIC50 for the three tested species was 32, 16, and 8 μg/ml for Trichophyton interdigitale, T. rubrum, and Epidermophyton floccosum isolates, respectively. The corresponding values for nano fluconazole were 8 μg/ml for the three tested species. Conclusion: MIC value for nano-fluconazole was lower than conventional fluconazole in all dermatophytes species tested; therefore, nano-fluconazole could inhibit the growth of dermatophytes better than fluconazole at a lower concentration of the drug.

scholarly journals Exemplifying the next generation of antibiotic susceptibility intensifiers of phytochemicals by LasR-mediated quorum sensing inhibition

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Arpit Shukla ◽  
Gaurav Shukla ◽  
Paritosh Parmar ◽  
Baldev Patel ◽  
Dweipayan Goswami ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Metabolic Pathways ◽  
Single Unit ◽  
Antimicrobial Properties ◽  
Well Being ◽  
Natural Compounds ◽  
Human Pathogens ◽  
Quorum Sensing Inhibition ◽  
In Silico Studies

AbstractThere persists a constant threat from multidrug resistance being acquired by all human pathogens that challenges the well-being of humans. This phenomenon is predominantly led by Pseudomonas aeruginosa which is already resistant to the current generations of antibiotic by altering its metabolic pathways to survive. Specifically for this microbe the phenomenon of quorum sensing (QS) plays a crucial role in acquiring virulence and pathogenicity. QS is simply the cross talk between the bacterial community driven by signals that bind to receptors, enabling the entire bacterial microcosm to function as a single unit which has led to control P. aeruginosa cumbersome even in presence of antibiotics. Inhibition of QS can, therefore, be of a significant importance to curb such virulent and pathogenic strains of P. aeruginosa. Natural compounds are well known for their antimicrobial properties, of which, information on their mode of action is scarce. There can be many antimicrobial phytochemicals that act by hindering QS-pathways. The rationale of the current study is to identify such natural compounds that can inhibit QS in P. aeruginosa driven by LasR, PhzR, and RhlR dependent pathways. To achieve this rationale, in silico studies were first performed to identify such natural compounds which were then validated by in vitro experiments. Gingerol and Curcumin were identified as QS-antagonists (QSA) which could further suppress the production of biofilm, EPS, pyocyanin, and rhamnolipid along with improving the susceptibility to antibiotics.

scholarly journals Growth kinetics of Salmonella Typhimurium and Listeria monocytogenes in buffalo milk under different processing and storage conditions

2021 ◽  
Vol 51 (11) ◽  
Author(s):  
Joelson Sousa Lima ◽  
Ana Paula Presley Oliveira Sampaio ◽  
Mylla Christy da Silva Dufossé ◽  
Paula Fernanda Morais de Sousa ◽  
Josyane Brasil da Silva ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Salmonella Typhimurium ◽  
Growth Kinetics ◽  
Storage Conditions ◽  
Buffalo Milk ◽  
Production Chain ◽  
Pasteurized Milk ◽  
Processing And Storage ◽  
And Storage ◽  
Kinetics Of

ABSTRACT: Buffalo milk is rich in nutrients and can serve as a substrate for the proliferation of microorganisms. Thus, the objective of the present study was to evaluate the growth kinetics of Salmonella Typhimurium and Listeria monocytogenes in buffalo milk under different processing and storage conditions. Samples of raw and pasteurized milk were inoculated with 1 CFU of each bacterium, separately and together, per 25 mL. After contamination, samples were stored at 8 °C or 37 °C, and bacterial counts were performed at 24, 48, and 168 h. In addition, the accompanying microbiota growth, pH, and the effect of these variables on the growth kinetics of microorganisms were monitored. The pathogens tested were able to proliferate under most conditions tested, reaching high titers throughout the experimental period. At 37 °C, there was a decrease in pH and an increase in the accompanying microbiota that interfered with the microbial growth curve. It was also observed that pasteurized milk subjected to 8 °C provided better conditions for the multiplication of bacteria. Therefore, it was concluded that care throughout the production chain, storage, and commercialization of milk must be adopted to guarantee the microbiological safety of this food.

scholarly journals FATTY ACID PROFILE OF NON-CONFORMING POOLED HUMAN MILK AS AFFECTED BY THE PROCESSING AND STORAGE CONDITIONS

2021 ◽  
Vol 9 (2) ◽  
pp. 46-54
Author(s):  
Otávio A. S. Ribeiro ◽  
Kely P. Correa ◽  
Mauricio O. Leite ◽  
Marcio A. Martins ◽  
Jane S. R. Coimbra
Keyword(s):  
Fatty Acid ◽  
Human Milk ◽  
Fatty Acid Profile ◽  
Storage Period ◽  
Storage Conditions ◽  
Milk Lipid ◽  
Fatty Acid Profiles ◽  
Operational Conditions ◽  
Processing And Storage ◽  
And Storage

The fatty acid's contents of non-conform pooled human milk can be affected by different processing and storage operational conditions. Besides, the knowledge of changes in the human milk fatty acid profile can help indicate its use in a given storage period, according to each newborn's specific need. Thus, in the present work, changes in the fatty acid profiles of three types of human milk (raw; pasteurized at 62.5 °C for 30 min; homogenized at 40 oC for 30 s followed by pasteurization) were studied during storage for six months in a freezer at -18 oC. Large variations were observed in the concentrations of polyunsaturated fatty acids, particularly of docosahexaenoic acid, with a reduction of almost 50% of its total. Palmitic and stearic acid contents also changed according to the conditions of processing and storage. Correlations between the decrease of long fatty acid chains and the increase of medium and short chains were verified.  Thus, we observe that operational conditions of processing and storing change human milk lipid profile, with some nutritional losses.

Sign in / Sign up

Export Citation Format

Share Document