Volume 7 (2020): Issue 3 (November 2020)

An efficient method for regioselective synthesis of 5-(dimethoxyphosphoryl)-allenecarboxylates by an atom economical [2,3]-sigmatropic rearrangement of the mediated 3-(dimethoxyphosphanyloxy)-alk-4-ynoates is described. Alkyl 5-(dimethoxyphosphoryl)-alka-3,4-dienoates can be readily prepared via reaction of alkyl 3-hydroxy-alk-4-ynoates with dimethylchlorophosphite in the presence of a base. Alkyl 3-hydroxy-alk-4-ynoates were prepared by reaction of the metallated acetylenes with commercialy available alkyl 3-oxoalkanoates.

The aim of this work is to study the effect of digestion on the total polyphenol content, flavonoids and the antioxidant activity of Aloe vera. Total polyphenol contents and flavonoid spectrophotometric methods: The evaluation of the antioxidant activity was carried out by three methods, DPPH, ABTS and CUPRAC. To confirm the results obtained we carried out an analysis by ATR-FTIR. The total phenol content found in the Aloe vera extract studied was 1.3638 mg EAG/100 g, while the content of flavonoids found in the Aloe vera extract studied was 0.690 mg EQ/100 g. The values of total polyphenols and flavonoids decreased under the effect of gastrointestinal digestion. The spectra obtained during the ATR-FTIR analysis show that Aloe vera is rich in phenolic compounds and flavonoids. Intense bands corresponding to O–H bonds, C=C bond, C–H, CO, CH₃ and CH₂ confirm the presence of these bioactive compounds. For both the DPPH and CUPRAC methods, Aloe vera extract reveals a strong antioxidant activity, which gradually decreases during the oral and gastric phase and then increases after the intestinal digestion. For the ABTS method, the antioxidant activity decreases during the oral phase, increases during the gastric phase and then decreases again during the intestinal phase.

The aim of this study was to evaluate antioxidant, antibacterial, and anticholinesterase activities of different extracts of an uninvestigated endemic species Bellevalia mauritanica Pomel, and identification of its phenolic and flavonoid content by a comprehensive and validated LC-MS/MS method using 37 phytochemical standards. Moreover, the phytochemical profiling of the studied extracts was accomplished by LC-MS-IT-TOF technique. Among all the tested extracts, ethyl acetate (EtOAc) of BRCE (bulbs-roots crude extract) was the most active one. It exhibited a medium antibacterial activity, good inhibition of acetylcholinesterase and a good antioxidant activity in ABTS^•+ (2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonique), DPPH^• (1,1’-diphenyl-2-picrylhydrazyl radical), and superoxyde DMSO (dimethyl sulfoxide) alkaline scavenging assays. LC-MS/MS analysis revealed that EtOAc extract had caffeic acid (1240.7 µg/g extract) and chloroform extract had vanillin (2048.5 µg/g extract) in considerable amounts. They also contained good amounts of certain phytochemicals such as protocatechuic acid (274.3 and 145.2 µg/g extract), p-coumaric acid (382.8 and 310.9 µg/g extract), ferulic acid (361.2 and 969.4 µg/g extract) and kaempferol (146.7 and 150.6 µg/g extract) respectively. LC-MS-IT-TOF screening revealed the presence of 91 major phytochemicals in the three extracts derived from bulb-roots crude extract.

Antifungal of bee products have been shown to be protective against microbial biofilms invasion Sahara honey and propolis were applied as an antimicrobial in treatment for many infections in Algeria. In this study, Fourier transform infrared spectroscopy (FTIR) analysis was utilized to characterize the chemical structures and functional groups. In addition, in this study, we determined the anti-candida activity of honey used alone or in combination with propolis. Proteins, carbohydrates, carboxylic acids, free amino acids, cellulose and lipids, ketones and phenol compounds were identified by FTIR analysis. Combination of Sahara honey and propolis increased antifungal efficacy, compared to compounds tested alone. Propolis increased the anti-candidal effect of Sahara honey. In addition, the treatment of Sahara honey and Propolis-Sahara honey catheters with a Candida albicans biofilms reduced biofilm formation after 24 and 48-h exposure period. The results provide evidence that honey/propolis combination may help in designing a more potent novel, natural antibiofilm blend at sufficiently low concentrations in medical domain.

The current research involves the study of the effect of thermal treatment in boiling water (cooking) on the nutrient components and phytochemical contents of lentils. The changes of phenolic compounds and antioxidant activity of lentils before and after cooking; as well as the recovered water are investigated. Total polyphenol, flavonoid and tannin content were determined spectrophotometrically using standards methods and LC-MS/MS. Antioxidant activity of methanolic extracts was evaluated using DPPH (2,2-diphenyl-lpicrylhydrazyl) and ABTS (2,2’-azinobis-(3-ethyl benzo thiazoline-6-sulfonic acid)) assays. As compared to the raw lentils, cooking caused significant (p<0.05) decreases in total phenolic content (TPC), total flavonoid content (TFC), DPPH and ABTS free radicals scavenging activity. The obtained results indicated that the polyphenol content of cooking water was significantly higher than that of cooked and raw lentils; however the most important antioxidant activity was recorded for raw lentils. Several phenolic compounds were identified in fresh, cooked lentils and cooking water. The major compound for the three samples is tannic acid with a very remarkable value in the cooking water; while the minor compounds are naringenin for cooked lentils, apigenin for raw lentils and cooking water. Neoformed compounds have been also detected in the cooking water such as: quercetin, hespritin, tr-caffeic acid and chlorogenous acid in the cooking water.

The present study aimed to assess the season and pregnancy influence on minerals serum of local rabbits raised in semi-arid climate type. Fifty-nine multiparous does was used in this study during 2019. The semi-intensive rhythm of reproduction was used. All pregnant does were at the late stage of pregnancy at the sampling date. Serum samples were collected in two seasons: winter and summer. In this study, biochemical parameters concentrations of pregnant rabbits were significantly higher (p<0,05) compared with non-pregnant rabbit. The value of biochemical parameters total protein, albumin, triglyceride, cholesterol, calcium, and phosphorusus changed significantly. In this study, most parameters were influenced by pregnancy.

Studies of medicinal plants have been conducted in many municipalities and regions in Bulgaria, but only species diversity has been studied. Data from ethnobotanical studies in Bulgaria are scarce. The conducted ethno-botanical study of medicinal plants on the territory of Balchik municipality is performed for the first time. As a result, we found that the population of the municipality uses a small part of the medicinal plants: 89 species out of a total of 845 medicinal plants in Bulgaria. Medicinal plants are used mainly for side applications (71%) and to a lesser extent for medicinal purposes (29%). Urban and rural populations use almost the same number of medicinal plants. There are significant differences in the number of plants used by different ethnic groups, age groups and groups with different levels of education. Women use more medicinal plants in human medicine, and in applications for other purposes, more plants are used by men. Most medicinal plants are used by people of active age. The people of Balchik Municipality use for various purposes mostly cultivated medicinal plants, rather than wild and mostly alien species, than native ones. The majority of respondents (78%) do not use medicinal plant substitutes. Most of the people (92.5%) are not aware of the shortcomings of the medicinal plants or the possible side effects of their use.

The study was performed at the Experimental Station of Agriculture - Khan Krum in the period 2018-2019. The experimental plantation was established in 2001, the early Bigareau Burlat, middle early Bing and the late Germersdorfer and Van were tested. The planting material was produced on a mahaleb rootstock. The distance of planting was 6 meters interrow spacing and 5 meters intrarow spacing. The experiment was based on three replications each of them reported on a separate tree. When analyzing the frost percentage of flowers, 400 blossoms were taken from three levels of the crown of each tree, the same number of fruits were taken to determine the cracking percentage. Percentage of damaged blossoms, yield kg/ha and percentage of fruit cracking as a result of fallen rains during harvest were established. The purpose of the study is to investigate the influence of abiotic factors on the yield and quality of four sweet cherry cultivars. In this regard, the frost percentage in the range of values was 67,3 - 100%. Bigareau Burlat yield was not obtained, and it was relatively low from Germersdorf and Bing (20,1 - 24,6 kg/ha) at Van 84,6 kg/ha. The number of cracked fruits due to fallen rains during harvest was relatively high in Van and Bing (39,8 - 47,4%), while in the Germersdorf cultivar it was lower - 21,2%.