Polyphenols contents, heavy metals analysis and in vitro antibacterial activity of extracts from Cladanthus arabicus and Bubonium imbricatum of Moroccan Origin

Anti-inflammatory compounds from the rhizome of Acorus calamus var. angustatus Besser and their mechanism

Seven compounds, named β-sitosterol (1), daucosterol (2), (+)-pinoresinol-β-D-glucoside (3), (-)-syringaresinol 4-O-β-D-apiofuranosyl-(1→2)- β-D-glucopyranoside (4), 4-hydroxybenzoic acid (5), 2-(3', 4'-dihydroxyphenyl)-1, 3-pepper ring-5-aldehyde (6) and spinosin (7) were isolated from the rhizome of Acorus calamus var. angustatus Besser. 3, 4, 6 and 7 were isolated from this medicinal plant for the first time. Structures were elucidated by physicochemical properties and extensive spectroscopic analysis, as well as by comparison with literature data. The anti-inflammatory activity and related mechanisms of the seven compounds showed that compounds 1-7 all increased the levels of GSH-PX and SOD and decreased the levels of MDA, TNF-α, IL-1β and IL-6. Compound 4 showed the best effect of anti-inflammatory and Beclin-1 inhibition. These results suggest that compound 4 has stronger anti-inflammatory effect and provide preliminary evidence that the mechanism of action of compound 4 in attenuating LPS-induced inflammatory damage may be related to the inhibition of Beclin-1-dependent autophagy.

Phytochemical, antileishmanial, antifungal and cytotoxic profiles of Thymelaea tartonraira (L.) All. extracts

Extracts from leaves and stems of Thymelaea tartonraira (L.) All. growing in Tunisia were characterised for the presence of flavonoids and phenolic acids by LC-ESI-MS analysis. Twelve flavonoids and ten phenolic acids were detected for the first time in the aerial parts of this plant species, the most abundant compounds being gallic acid, kaempferol, catechin, chlorogenic acid, naringenin and acacetin. The extracts were subjected to in vitro antileishmanial, antifungal and cytotoxic assays, showing promising antileishmanial activity for the E6 dichloromethane extract from the stems (IC50 values of 1.12 ± 0.50 and 5.41 ± 1.84 µg/mL on L. donovani axenic and intramacrophagic amastigotes, respectively) at the level of the reference drug miltefosine for axenic model. No antifungal activity was observed against Candida albicans (CAAL) and Aspergillus fumigatus (ASFU) strains, with the exception of the E6 dichloromethane extract (IC50 value of 25.28 ± 4.89 µg/mL on CAAL93 strain). Low toxicity was also highlighted against macrophages Raw 264.7 cells. These promising results point out Thymelaea tartonraira (L.) All. extracts as a valuable source of new natural products to combat leishmaniasis.

Natural antimicrobials from plants: Recent advances and future prospects

Plant-based antimicrobial substances have emerged as promising alternatives to conventional antibiotics and preservatives. Although many review studies have been done in this field, many of these reviews solely focus on specific compounds from particular perspectives. This paper aims to provide a comprehensive review on the various types of plant-based antimicrobial substances, the extraction and purification processes, as well as the application and safety issues. Combining different natural plant-derived substances shows promise in enhancing antimicrobial activities. Moreover, despite the existence of various methods (e.g., microwave-assisted extraction, supercritical fluid extraction) to extract and purify antimicrobial substances, isolating pure compounds remains a laborious process. Sustainability issues should also be considered when developing extraction methods. Additionally, the extraction process generates a significant amount of plant waste, necessitating proper utilization to ensure economic viability. Lastly, not all plant-derived substances are safe, and further research is needed to investigate their toxicity before widespread application.

Effect of Filtration Process on Oxidative Stability and Minor Compounds of the Cold-Pressed Hempseed Oil during Storage

Cold-pressed hempseed oil (HO) has been increasingly exploited in the human diet for its excellent nutritional and healthy properties. However, it has a high content of polyunsaturated fatty acids (PUFAs) and chlorophylls, which inevitably accelerate its oxidative deterioration, especially in the presence of light. In this scenario, the filtration technology may ameliorate the oxidative stability of the oil, with positive effects on its nutritional quality and shelf life. Therefore, in this study, the oxidative stability and minor compounds of non-filtered and filtered HO (NF-HO and F-HO) were monitored over 12 weeks of storage in transparent glass bottles. F-HO showed a better hydrolytic and oxidative status than NF-HO during storage. As a result, F-HO also displayed better preservation of total MUFAs and PUFAs in the autoxidation process. Filtration consistently reduced chlorophylls, thus causing a variation in the natural color of HO. Accordingly, F-HO not only revealed an increased resistance to photooxidation but it was also suitable for storage in clear bottles within 12 weeks. F-HO predictably showed lower carotenoids, tocopherols, polyphenols, and squalene compared to NF-HO. However, filtration appeared to play a "protective role" toward these antioxidants, which had lower degradation rates in F-HO than NF-HO for 12 weeks. Interestingly, the element profile of HO was not affected by filtration and remained stable during the study period. Overall, this study may be of practical use to both producers and marketers of cold-pressed HO.

Antimicrobial activity in Asterceae: The selected genera characterization and against multidrug resistance bacteria

Plants from the Asteraceae family are widely used as ethno medicines to treatment parasitic, malaria, hematemesis, pruritus, pyretic, anthelmintic, wound healing. The aim of this review is to provide an overview of Asteraceae plants antimicrobial activity. The most relevant results from the published studies are summarized and discussed. The species in genus of Artemisia, Echinacea, Centaurea, Baccharis, and Calendula showed antimicrobial activity. Most of these species are usually used as ethno medicines to treat infection, inflammation, and parasitics. The effective part or component for antimicrobial was essential oil and crude extract, and essential oil attracted more attention. It was also reported that nanoparticles coated with crude extract were effective against multidrug resistant bacteria. For multidrug resistant bacteria study, the species in Armtemisia were the most investigated, and Staphylococcus aureus and Escherichia coli were the most studied multidrug resistant strains. The antimicrobial activity was evaluated mainly based on the results of minimum inhibitory concentration (MIC). Few reports have been reported on minimum bactericide concentration (MBC) and its antibacterial mechanisms. According to the reported study results, some plants in Asteraceae have the potential to be developed as bacteriostatic agents and against multidrug resistant bacteria. However, most studies are still in vitro, further clinical and applied studies are needed.

Evaluation of antibacterial activity of compounds isolated from the peel of Newhall navel orange

Fifteen compounds including one flavanone hesperitin (1), two cinnamic acid derivatives as (E)-4-hydroxycinnamic acid (2) and (E)-ferulic acid (3), eight polymethoxyflavones (PMFs) (4-11), and four hydroxylated PMFs (12-15) isolated from orange peel were subjected to antibacterial evaluation. Compounds 1-3 exhibited wide-spectrum antibacterial effects against four test strains involving Bacillus subtilis, Staphylococcus aureus, Xanthomonas citri subsp. citri (Xcc), and Meticillin-resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentrations (MICs) ranging from 0.0312 to 0.125 mg/mL. In contrast, all PMFs showed weak antibacterial activity against these four strains with MICs being equal to or more than 0.125 mg/mL. Hydroxylated PMFs demonstrated better antibacterial effect against Xcc relative to PMFs. In addition, the synergistic effect against Xcc was obtained when compounds 1 and 3 were combined. Furthermore, the scanning electron microscopy (SEM) results of Xcc treated with both compounds 2 and 3 showed shrunken and rough surface morphologies, indicative of the cell membrane damage.

Analysis of Volatiles in Senecio anteuphorbium Essential Oil with a Focus on Its Allelopathic Effect by Means of Gas Chromatography

The present study aimed to investigate Senecio anteuphorbium, an endemic plant growing in West Morocco and widely used in local folk medicine. The essential oil (EO) extracted from the aerial parts was analyzed by gas chromatography and tested for allelopathic activity. The quantitation of the volatiles was carried out by means of GC-FID with response factors, which were validated through reliable calibration procedures, based on external and internal standardization. This analytical approach allowed to define the real concentration of each constituent (weight%, g/100 g) alongside the conventional relative percent. On the other hand, the identification process was supported by a dual matching based on both mass spectra and retention indices. The essential oil resulted in being rich in sesquiterpenes, with the predominant constituents being bicyclogermacrene (22.75 g/100 g), spathulenol (25.26 g/100 g), epi-γ-eudesmol (6.8 g/100 g), and selina-4,11-diene (5.08 g/100 g). The allelopathic effect was evaluated by studying the inhibition of the germination and growth of Lactuca sativa seeds. A potent allelopathic effect was recorded by the essential oil at a dose of 0.281 mg/mL, with almost a total inhibition of germination.

Role of nutraceuticals on neurodegenerative diseases: neuroprotective and immunomodulant activity

Neurodegeneration is a degenerative process characterized by the progressive loss of the structure and function of neurons that involves several immune cells. It is the primary cause of dementia and other several syndromes, known as neurodegenerative diseases. These disorders are age-related and it is estimated that by 2040 there will be approximately 81.1 million people suffering from these diseases. In addition to the traditional pharmacological therapy, in recent years nutraceuticals, naturally based compounds with a broad spectrum of biological effects: anti-aging, antioxidants, hypoglycaemic, hypocholesterolemic, anticancer, anxiolytic, antidepressant, etc., assumed an important role in counteracting these pathologies. In particular, several compounds such as astaxanthin, baicalein, glycyrrhizin, St. John's wort, and Ginkgo biloba L. extracts show particular neuroprotective and immunomodulatory abilities, involving several immune cells and some neurotransmitters that play a critical role in neurodegeneration, making them particularly useful in improving the symptoms and progression of neurodegenerative diseases.

Cardoon (Cynara cardunculus L. var. altilis) seeds presscake: a natural by-product for pigs feeding

The cardoon seeds presscake is a natural by-product resulting from the mechanical treatment of the cardoon plant seeds. The chemical composition suggests its possible use in animal nutrition due to the content of proteins, fibre, lipids and biologically active substances. The presscake studied contained 7.1% of fat, 26.8% of fibre, 23.9% of protein, 37.1% of nitrogen-free extract and a goodly phenolic content (13.36 mg GAE g^-1 DW). The major fatty acids were oleic (26.5%) and linoleic (58.4%), showing a high degree of unsaturation. This study evaluated for the first time the inclusion of the cardoon presscake in pigs' diet. The effects of the dietary treatment on meat quality and fatty acids profile were assessed. The results indicate that the intramuscular fat (IMF) was higher in the untreated animals. The monounsaturated fatty acids (MUFAs) were lower in the IMF of the treated pigs, whereas the polyunsaturated fatty acids (PUFAs) were higher.

Antibacterial and anti-biofilm activities of paeonol against Klebsiella pneumoniae and Enterobacter cloacae

Paeonol, the active ingredient of Paeonia lactiflora root bark, is widely used in traditional Chinese medicine. Few studies have reported the antibacterial activity of paeonol against bacterial pathogens. In this study, the antibacterial and anti-biofilm performance of paeonol against Klebsiella pneumoniae and Enterobacter cloacae was investigated as well as its mechanisms of action. Paeonol effectively inhibited the growth of K. pneumoniae and E. cloacae with a minimum inhibitory concentration of 64 μg ml^-1 and it was shown to disrupt the integrity of bacterial cell membranes, and alter cell morphology. Moreover, paeonol exhibited a potent inhibitory effect against adhesion and biofilm formation by K. pneumoniae and E. cloacae. In particular, paeonol efficiently compromised cells within biofilms, and dispersed mature biofilms. Therefore, the present study suggests that paeonol is a promising alternative antibacterial and anti-biofilm agent for combating infections caused by planktonic and biofilm cells of K. pneumoniae and E. cloacae.

Disaccharide Type Affected Phenolic and Volatile Compounds of Citrus Fiber-Blackberry Cream Fillings

The food industry is continuously developing ingredients, processing methods and packaging materials to improve the quality of fruit products. The aim of this work was to study the possibility of using citrus fiber in the preparation of blackberry cream fillings in combination with disaccharides (sucrose, maltose and trehalose). Evaluations of the phenolics, proanthocyanidins, antioxidant activity, color and volatiles of blackberry cream fillings were conducted after preparation and after three months of storage. Blackberry cream fillings were prepared from citrus fiber (5%), blackberry juice and disaccharides (50%). Disaccharide type had an effect on all investigated parameters. The highest phenol content was in fillings with trehalose (4.977 g/100 g) and the lowest was in fillings prepared with sucrose (4.249 g/100 g). The same tendency was observed after storage. Fillings with maltose had the highest proanthocyanidins content (473.05 mg/100 g) while fillings with sucrose had the lowest amount (299.03 mg/100 g) of these compounds. Regarding volatile compounds, terpenes and aldehydes and ketones were evaluated in the highest concentration. Terpenes were determined in the highest concentration in fillings with trehalose (358.05 µg/kg), while aldehydes and ketones were highest in fillings with sucrose (250.87 µg/kg). After storage, concentration of volatiles decreased. These results indicate that the selection of adequate disaccharides is very important since it can influence the final quality of the product.

Screening of Antibacterial Activity, Antioxidant Activity, and Anticancer Activity of Euphorbia hirta Linn. Extracts

This study aimed to screen the anticancer and antioxidant potential and antimicrobial activity of methanol, petroleum ether, chloroform, ethyl acetate, butanol of Euphorbia hirta Linn. extracts (EH-Me, EH-PE, EH-Ch, EH-EA and EH-Bu, respectively). The results of 2,2-diphenyl-1-pycrylhydrazyl (DPPH) radical scavenging assay and lipid peroxidation inhibition assay showed that EH-EA was the strongest antioxidant (IC50 = 10.33 ± 0.01 µg/mL; IC50 = 1.48 ± 0.12 µg/mL, respectively) compared to all other extracts. In the antimicrobial activity of the extracts against eight strains of Gram-positive and Gram-negative bacteria using the agar disc diffusion method, we found the EH-EA to be the best antimicrobial agent. Anticancer activities of those extracts were examined by sulforhodamine B (SRB) in vitro cytotoxicity assay on two cancer cell lines, including lung cancer cells NCI-H460 and liver cancer cells Hep G2. EH-EA at concentration of 100 μg/mL has significant inhibitory activity the growth of lung cancer cells NCI-H460 and liver cancer cells Hep G2 compared to all other extracts. Our results suggest that E. hirta Linn. extracts possess significant biological activities, including antimicrobial, antioxidant, and moderate anticancer properties. Our results show that this plant could be a good source for natural antioxidants and a possible pharmaceutical supplement. Among five analyzed extracts, EH-EA extract has the strongest activities, and should be used to determine phytochemicals and mechanisms of these activities.

Resistance to multiple first-line antibiotics among Escherichia coli from poultry in Western Algeria

BACKGROUND AND AIM

Escherichia coli can cause a number of serious infections both in human and veterinary medicine. Their management is increasingly complicated by the emergence and dissemination of multiresistance to various first-line antimicrobial agents. This study aimed to evaluate the resistance level to the commonly used antibiotics, with a focus on the first-line antimicrobial agents, in E. coli strains isolated from poultry in Western Algeria.

MATERIALS AND METHODS

E. coli culture was done on MacConkey agar and their identification was determined by AP20E system. For susceptibility testing, disk diffusion method to 14 antimicrobials, including first-line antibiotics, was used according to Kirby-Bauer disk diffusion method in Mueller-Hinton agar and the results were interpreted according to the Clinical and Laboratory Standards Institute guidelines. E. coli isolates were considered as multidrug resistance (MDR) when found resistant to at least one antimicrobial agent of three different families of antibiotics. Double-disk synergy and combination disk tests were used for initial screening and confirmation for extended-spectrum β-lactamases (ESBLs) production, respectively.

RESULTS

A total of 145 E. coli strains were isolated in this study. High resistance levels to various antibiotics, including commonly used first-line antimicrobial agents, were recorded in this study. The highest resistance level was observed against nalidixic acid (90.34%, n=131), followed by tetracycline (86.89%, n=126), ampicillin (82.75%, n=120), enrofloxacin (80.68%, n=117) and neomycin (80.68%, n=117), trimethoprim/sulfamethoxazole (73.79%, n=107), norfloxacin (72.41%, n=105) and cephalothin (72.41%, n=105), amoxicillin/clavulanic acid (51.72%, n=75), chloramphenicol (22.75%, n=33), nitrofurantoin (17.24%, n=25), gentamicin (13.10%, n=19), and ceftiofur (3.44%, n=5). Moreover, resistance to multiple first-line antibiotics was also demonstrated in the present study. Overall, 139 out of 145 isolates (95.86%) demonstrated MDR (resistant to at least three antibiotics). In addition, five E. coli isolates (3.44%) were confirmed to be ESBL producers.

CONCLUSION

The alarming rate of E. coli resistant to multiple first-line antibiotics in poultry demands intensified surveillance. These results call for taking drastic measures to preserve antibiotic effectiveness and reduce the emergence risks of extensively drug-resistant and pandrug-resistant E. coli isolates.

Antioxidant and Lipoxygenase Inhibitory Activities of Essential Oils from Endemic Plants of Côte d'Ivoire: Zanthoxylum mezoneurispinosum Ake Assi and Zanthoxylum psammophilum Ake Assi

Zanthoxylum mezoneurispinosum Ake Assi and Zanthoxylum psammophilum Ake Assi are species endemic to Côte d’Ivoire. In this study, we determined, for the first time, the composition and biological activities of essential oils obtained from each of these plants. Essential oils were obtained by hydrodistillation from different organs of each plant with a Clevenger-type apparatus and analyzed by gas chromatography–mass spectrometry (GC-MS). Thirty-four components, accounting for more than 99.9% of the overall composition, were identified in the oils. The Z. psammophilum leaf and trunk bark oils exhibited two unusual methylketones, undecan-2-one and tridecan-2-one, whereas the root oil was rich in thymol and sesquiterpenoids. The Z. mezoneurispinosum leaf and trunk bark oils were rich in monoterpenoids, whereas sesquiterpenoids were predominant in the root oil. These samples produced, for the first time, some new chemical profiles of essential oils. The oils’ antioxidant activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity and ferric reducing antioxidant power (FRAP) assays. The results showed that the essential oil isolated from roots of Z. mezoneurispinosum had the highest antioxidant activity, which is in accordance with the high thymol content of that oil. We also determined the lipoxygenase inhibitory activities of the essential oils. The results showed that all of the tested oils displayed high and close lipoxygenase inhibitory activities.

Protein hydrolysates from anchovy waste: purification and chemical characterization

The aim of this study is to prompt the recovery of industrial by-products through the production of new functional foods; it takes advantage from new throughput technologies with low environmental impact and high economic sustainability. In the field of fish processing, in order to recover the worthy protein-rich fish waste, residues from the production of Anchovies (Engraulis encrasicolus) have been converted into hydrolysate through enzymatic treatment. The obtained hydrolysate product showed a promising biological and nutritional content made by differently sized peptides and free amino acids endowed with assessed benefic effects. The study showed the possibility to produce a dry powder with an activity water (aw) of 0.3-0.5 and an essential amino acids (EAA) fraction of 42.0% over the total amino acids (TAAs). These results pave the way to the smart recovery of commercial products featured by high nutritional value, either as stand-alone items or as components of functional foods.