Plant Sources of Propolis: An Update from a Chemist's Point of View

The newest developments in research on propolis plant sources are summarized. Special attention is paid to data based on reliable chemical evidence including comparison between propolis samples and plant material, and on well-documented bee behavior. A number of new proved propolis source plants are listed. Hypothetical sources, suggested as a result of comparison of propolis chemical composition and literature data about particular plants are also discussed.

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Impact of Harvest Conditions and Host Tree Species on Chemical Composition and Antioxidant Activity of Extracts from Viscum album L.

Molecules ◽

10.3390/molecules26123741 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3741

Author(s):

Wioleta Pietrzak ◽

Renata Nowak

Keyword(s):

Antioxidant Activity ◽

Biological Activity ◽

Chemical Composition ◽

Tree Species ◽

Plant Material ◽

Plant Secondary Metabolites ◽

Host Tree ◽

Host Tree Species ◽

High Antioxidant Activity ◽

Mistletoe Extracts

The content of plant secondary metabolites is not stable, and factors such as the region/location effect and seasonal variations have an impact on their chemical composition, especially in parasitic plants. Research in this area is an important step in the development of quality parameter standards of medicinal plants and their finished products. The effects of the time and place of harvest and the host tree species on the chemical composition and antioxidant activity of mistletoe extracts were investigated. Statistical tools were used to evaluate the results of the spectrophotometric and LC-ESI-MS/MS studies of the phenolic composition and antioxidant activity. The investigations indicate that the qualitative and quantitative composition, influencing the biological activity of mistletoe extracts, largely depends on the origin of the plant. The mistletoe extracts exhibited a rich phenol profile and high antioxidant activity. The chemometric analysis indicated that mistletoe collected from conifers (Viscum abietis and Viscum austriacum) had the most advantageous chemical composition and antioxidant activity. Moreover, the chemical profile and biological activity of the plant material were closely related to the climatic conditions and location of the harvested plant. Higher levels of phenolic compounds and high antioxidant activity were found in extracts obtained from plant material collected in cold weather with the presence of snow and less sunshine (autumn–winter period).

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Stem Lettuce and Its Metabolites: Does the Variety Make Any Difference?

Foods ◽

10.3390/foods10010059 ◽

2020 ◽

Vol 10 (1) ◽

pp. 59

Author(s):

Janusz Malarz ◽

Klaudia Michalska ◽

Anna Stojakowska

Keyword(s):

Chemical Composition ◽

Plant Material ◽

Methanolic Extract ◽

Sesquiterpene Lactones ◽

Scavenging Activity ◽

Nmr Analysis ◽

Caffeic Acid Derivatives ◽

Aerial Parts ◽

Dpph Scavenging Activity ◽

Dpph Scavenging

The objective of the present study was to characterize chemical composition of hitherto unexamined aerial parts of Lactuca sativa var. angustana cv. Grüner Stern. In contrast to leafy and head varieties of the lettuces, asparagus lettuce grown in Europe is much less studied. Fractionation of a methanolic extract from leaves of L. sativa cv. Grüner Stern, supported with HPLC/DAD and 1H NMR analysis, led to the isolation and/or identification of numerous terpenoid and phenolic compounds, including five apocarotenoids—(-)-loliolide, (+)-dehydrovomifoliol, blumenol A, (6S,9S)-vomifoliol, and corchoionoside C; three sesquiterpene lactones; two lignans—((+)-syringaresinol and its 4-O-β-glucoside); five caffeic acid derivatives; and three flavonoids. Some of the compounds, to the best of our knowledge, have never been isolated from L. sativa before. Moreover, monolignols, phenolic acids and a tryptophan-derived alkaloid were found in the analyzed plant material. Stems, leaves and shoot tips of the asparagus lettuce were examined to assess their phenolics and sesquiterpene lactone content as well as DPPH scavenging activity. Another stem lettuce—L. sativa var. angustana cv. Karola, two cultivars of leafy lettuces and one species of wild lettuce—L. serriola, were also examined as a reference material using HPLC/DAD. The results have been discussed regarding our previous studies and the literature data available.

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Chemical Composition and Functional Properties of Dietary Fibre Concentrates from Winemaking By-Products: Skins, Stems and Lees

Foods ◽

10.3390/foods10071510 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1510

Author(s):

María Ángeles Rivas ◽

Rocío Casquete ◽

María de Guía Córdoba ◽

Santiago Ruíz-Moyano ◽

María José Benito ◽

...

Keyword(s):

Chemical Composition ◽

Functional Properties ◽

Dietary Fibre ◽

Water Retention ◽

Point Of View ◽

Water Retention Capacity ◽

Retention Capacity ◽

Oil Retention ◽

High Antioxidant Activity ◽

By Products

The objective of this study was to evaluate, from a technological and nutritional point of view, the chemical composition and functional properties of the industrial winemaking by-products, namely skins, stems and lees. The chemical and physical characteristics, as well as the functional properties (fat and water retention and swelling capacity, antioxidant capacity, and their prebiotic effect), of the dietary fibre of these by-products were studied. The results showed that the skins, stems, and lees are rich in fibre, with the stem fibre containing the highest amounts of non-extractable polyphenols attached to polysaccharides with high antioxidant activity and prebiotic effect. Lee fibre had the highest water retention capacity and oil retention capacity. The results reveal that winemaking by-products could be used as a source of dietary fibre with functional characteristics for food applications.

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YIELD, ECONOMICALLY VALUABLE INDICATORS AND CHEMICAL COMPOSITION OF BLUE HONEYSUCKLE UNDER CONDITIONS OF SAKHALIN TRADE-WIND LITTORAL CLIMATE

Bulletin оf Kamchatka State Technical University ◽

10.17217/2079-0333-2021-56-64-73 ◽

2021 ◽

pp. 64-73

Author(s):

V.N. Yefanov ◽

◽

E.V. Mitusova ◽

Keyword(s):

Chemical Composition ◽

Point Of View ◽

Trade Wind ◽

Plant Industry ◽

Monsoon Climate ◽

Experimental Station ◽

Vavilov Institute ◽

Household Gardens ◽

Blue Honeysuckle

The blue honeysuckle is the earliest ripening berry, which ripens 7–10 days earlier than the garden strawber-ries under the conditions of Sakhalin's climate. It is resistant to lower fungi and parasites and can be cultivat-ed without pesticides. Currently, many honeysuckle varieties with fruits of different morphologies and chemical composition have been bred. We analyzed values of economically valuable indicators and chemical composition in 14 varieties of honeysuckle, which grow in the monsoon climate of Sakhalin. To assess the most productive variety, the values of each character were presented as percentage of the maximum for each indicator. Knowing the total values of characters under investigation made it possible to choose the best va-rieties, from authors` point of view, to grow in the household gardens in the monsoon climate of Sakhalin: from the Pavlovsk Experimental Station of Vavilov Institute of Plant Industry – Leningradsky giant (506.4%), Berel (432.9%) and Viola (423.4%).

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Application of papain enzyme in technology of meat products

Animal Science and Food Technology ◽

10.31548/animal2021.03.005 ◽

2021 ◽

Vol 12 (3) ◽

Author(s):

V. М. Israelian ◽

◽

N. V. Holembovska ◽

N. M. Slobodyanyuk ◽

◽

...

Keyword(s):

Chemical Composition ◽

Raw Materials ◽

Meat Products ◽

Chloride Concentration ◽

Enzyme Concentration ◽

Point Of View ◽

Meat Production ◽

High Catalytic Activity ◽

Medium Temperature ◽

Enzyme Preparations

Production of enzyme preparations occupies one of the leading places in modern biotechnology and belongs to the industries whose production is constantly growing and the field of application is expanding. Various enzyme preparations are widely used in the field of nutrition, this is due to their high catalytic activity, specificity of action, the ability to carry out biochemical reactions in mild conditions. Therefore, it is advisable to use enzymes for various industrial processes, both from an economic and technological point of view. The purpose of the work was to investigate the chemical composition and the activity of papain enzyme preparation with subsequent application in technology of meat production in order to increase the biological value and improve the functional and technological properties of the finished product. The analysis of literature sources and own research shows the prospects for research and the application of enzymes and enzyme preparations based on them in the food industry, as it improves the quality of finished products and the level of greening of production, more rational use of raw materials. As a result of a study of the chemical composition, it was found that the papain enzyme has a high protein content of 87.44%, due to which it has a broader effect on meat proteins. The dependence of papain activity on the pH of the medium, temperature, sodium chloride concentration, and enzyme concentration was studied. The results of the studies showed that the highest papain activity is in the range at pH 5.5–6.0. The enzyme has a maximum collagenase activity at pH 6.0 and at a temperature of 50–60 °C.

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Honey: Chemical Composition, Stability and Authenticity

Foods ◽

10.3390/foods8110577 ◽

2019 ◽

Vol 8 (11) ◽

pp. 577

Author(s):

Olga Escuredo ◽

M. Carmen Seijo

Keyword(s):

Chemical Composition ◽

Physical Properties ◽

Statistical Methods ◽

Analytical Techniques ◽

Food Product ◽

Botanical Origin ◽

Special Issue ◽

Research Papers ◽

Practical Solution ◽

Plant Sources

This Special Issue contains innovative research papers on the characterization, chemical composition and physical properties of honey. This constitutes very useful information to avoid frauds and to guarantee the authenticity of this food product. The knowledge of the particularities of honey is increasingly demanded by beekeepers and consumers, and also by labs to typify honeys according to their botanical origin and to check their quality. Melissopalynological, sensorial and physicochemical techniques are being used to study the characteristics of honeys samples from different plant sources and geographical areas. The combination of these analytical techniques with mathematical and statistical methods or chemometrics allows researchers to identify a set of variables or individual parameters that define independent samples, providing a practical solution to classify honey according to the geographical or the botanical origin.

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Overlay materials used for increasing lifetime of machine parts working under conditions of intensive abrasion

Research in Agricultural Engineering ◽

10.17221/64/2011-rae ◽

2013 ◽

Vol 59 (No. 1) ◽

pp. 16-22 ◽

Cited By ~ 11

Author(s):

M. Müller ◽

P. Hrabě

Keyword(s):

Wear Resistance ◽

Chemical Composition ◽

Abrasive Wear ◽

Laboratory Experiments ◽

Optical Emission Spectroscopy ◽

Optical Emission ◽

Point Of View ◽

Laboratory Results ◽

Machine Parts ◽

Materials Used

We evaluated a degree of the machine part abrasive wear with secondary focus on their hardness. The paper states laboratory results of overlay systems from their wear resistance point of view. Laboratory experiments were carried out by two-body abrasion on bonded abrasive of a P120 granularity. The results proved an increased abrasive wear resistance of martensitic, ledeburitic and stellitic overlays against eleven different original products. The overlay UTP Ledurit 60 reached the optimum values. The GD-OES (Glow Discharge Optical Emission Spectroscopy) method proved the different chemical composition of the overlay from the stated chemical composition of the overlaying electrode.    

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Sur la composition chimique moyenne des amphibolites

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.s6-iii.1-3.153 ◽

1953 ◽

Vol S6-III (1-3) ◽

pp. 153-173 ◽

Cited By ~ 3

Author(s):

Pierre Lapadu-Hargues

Keyword(s):

Chemical Composition ◽

Sedimentary Rocks ◽

Point Of View ◽

Igneous Rocks ◽

Chemical Analyses ◽

Average Chemical Composition ◽

Composition Chimique

Abstract In a majority of cases, amphibolites derived from sedimentary rocks can be distinguished from those derived from dioritic or gabbroic igneous rocks on the basis of average chemical composition. From the purely chemical point of view, it is possible to consider that eclogites result from metamorphism of certain types of heteromorphic gabbros such as the ariegites,and ultimately give rise to amphibolitic rocks. Chemical analyses are included.

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