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Morus plants played a pivotal role in ancient Chinese sericulture and silk production, which served as critical components of economy and culture. Besides, many parts of mulberry trees, including roots, leaves, stems, and fruits, hold various medicinal value, and have been utilized in traditional medicine for thousands of years. The chemical composition of mulberry has been reported in many literatures, while the characteristic compounds have not been systematically summarized. In this review, we focused on the polyphenolic compounds in mulberry, including flavonoids, 2-arylbenzofurans, and Diels–Alder (D–A) adducts, and summarized their structural features, structure-activity relationships, and potential biosynthetic pathways. The results revealed a characteristic class of 2′-hydroxylated flavonoids and stilbenes which played an important role in the biosynthesis of downstream 2-arylbenzofurans and D–A adducts in mulberry but had been overlooked by most studies. The prenylated modifications of different compounds were also discussed and their function as precursors of D–A adducts was emphasized. We also describe the effects of different modifications on biological activities. Besides, the chemical composition of Morus was most similar to that of Artocarpus in the Moraceae family in that they had almost identical characteristic compounds. Finally, a putative total biosynthetic pathway of D–A adducts in mulberry was proposed based on structure derivation and combination of verified reactions. This review contributes to the understanding of the biological activity and biosynthesis of the characteristic components of Morus plants. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of dietary Allium mongolicum Regel powder (AMRP) supplementation on the growth performance, meat quality, antioxidant capacity and muscle fibre characteristics of fattening Angus calves. Growth performance data and longissimus thoracis (LT) samples were collected from four groups of fattening Angus, which were fed either a basal diet (CON) or a basal diet supplemented with an AMRP dose of 10 (LAMR), 15 (MAMR), or 20 g/animal/day AMRP (HAMR) for 120 days before slaughter. AMRP addition to the feed improved growth performance and meat quality and altered muscle fibre type. Some responses to AMRP supplementation were dose dependent, whereas others were not. Together, the results of this study demonstrated that dietary supplementation with 10 g/animal/day AMRP was the optimal dose in terms of fattening calf growth performance, while 20 g/animal/day AMRP supplementation was the optimal dose in terms of meat quality. • The role of AMRP in the growth performance of cattle were reported for the first time. • Dietary AMRP supplementation increased calf average daily gain and feed efficiency. • Dietary AMRP supplementation increased meat quality without affecting meat colour. • Dietary AMRP supplementation may manipulate the transformation of muscle fibre types. [ABSTRACT FROM AUTHOR]

• Antimicrobial potential of rosmarinic acid confirmed towards 11 Candida strains and 13 bacterial pathogens. • Antibiofilm properties include inhibition of Candida attachment, eradication of established biofilms, moderate reduction of exopolysaccharide production. • Antimicrobial mechanisms include disturbance in mitochondria activity and cell membrane integrity, moderate reduction in protease production but not binding to ergosterol. Emerging antimicrobial resistance and side effects associated with antibiotics overuse are driving the need for the novel antimicrobial therapeutics with the natural compounds considered as an appealing alternative. Rosmarinic acid is abundantly present in medicinal plants. This study aimed to elucidate its possible role as an inhibitor of planktonic and biofilm microorganism growth, along with its antifungal mechanisms. In this study, rosmarinic acid showed promising anticandidal (MIC 0.1–0.2 mg/mL) and antibacterial (MIC 0.002->0.8 mg/mL) activity. To some extent it was able to prevent cell attachment and eradicate established biofilms. Rosmarinic acid antifungal mechanisms included reduction of mitochondrial activity, alteration in membrane integrity, and slight inhibition of protease production but not binding to ergosterol. Its antibiofilm activity was moderately linked to the reduction in exopolysaccharide production. Considering its wide antimicrobial and antibiofilm spectrum rosmarinic acid could be further explored as an antimicrobial agent along with range of medicinal plants with rosmarinic acid as the dominant compound. Nevertheless, rosmarinic acid could serve as the basis for the development of antimicrobials employing novel mechanisms of activity. [ABSTRACT FROM AUTHOR]

A mammoth amount of tea pruning litter (TPL) is generated through the pruning of the tea plant and kept on the soil surface which makes the soil sick due to the accretion of allelochemicals from it. Therefore, appropriate management of TPL is very much crucial. This study was conducted to assess the role of tea pruning litter biochar (TPLBC) as a soil conditioner towards the growth and regulations of two popularly grown tea cultivars (TV23 and S.3A/3) in India. Altogether twenty-nine (29) parameters comprising functional groups, plant biomass, and physiological and biochemical properties have been reported in this study to understand the feasibility of TPLBC for tea cultivation. TPLBC amendment of 400 kg ha−1 was best suited for the used cultivars, leading to an increase in chlorophyll content, photosynthetic rate, stomatal conductance, transpiration rate, and water use efficiency by 25.68%, 49.61%, 84.00%, 126.93%, and 3.87% respectively. The maximum increase in plant total biomass, shoot biomass, and root biomass was attended at 110%, 31%, and 117%, respectively at 400 kg TPLBC ha−1 over control. The results also revealed an increase in the content of sugar, starch, phenol, total polyphenol, and amino acids with an increasing dose of TPLBC up to 400 kg ha−1. However, with 500 kg ha−1 TPLBC, plant biomass, and polyphenol content were decreased but oxidative stress was increased. Considering all the 29 variables it can be concluded that the soil amendment with 400 kg TPLBC ha−1 was most promising for both TV23 and S.3A/3 clones. [Display omitted] • The first report of tea pruning litter biochar (TPLBC) in improving soil fertility. • TPLBC reduced soil sickness, thus impacting the growth and yield of tea plants. • 400 kg TPLBC ha−1 proved to be the best treatment based on 29 variables. • Application of more than 400 kg TPLBC ha−1 was found to be unsuitable. [ABSTRACT FROM AUTHOR]

The complexity of natural products always leads to the co-elution of interfering compounds with bioactive compounds, which then has a detrimental effect on structural elucidation. Here, a new method, based on selective solid phase extraction combined with 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) spiking and high performance liquid chromatography–diode array detector–quadrupole time-of-flight tandem mass spectrometry (HPLC–DAD–QTOF-MS/MS), is described for sensitive screening, selective extraction and identification of polyphenolic antioxidants in Polygonatum odoratum . First, 25 polyphenolic antioxidants ( 1 – 25 ) were screened by DPPH spiking with HPLC. Second, polydopamine coated Fe 3 O 4 microspheres (Fe 3 O 4 @PDA) were prepared to selectively extract target antioxidants with extraction efficiency from 55% to 100% when the amount of Fe 3 O 4 @PDA, extraction time, desorption solvent and time were 10 mg, 20 min, acetonitrile, and 5 min. Third, 25 antioxidants (10 cinnamides and 15 homoisoflavanones) were identified by HPLC–DAD–QTOF-MS/MS. Furthermore, the DPPH scavenging activities of purified compounds (IC 50 , 1.6–32.8 μg/mL) validated the method. Among the identified antioxidants, four of them ( 12 , 13 , 18 and 19 ) were new compounds, four of them ( 2 , 4 , 8 and 14 ) were first obtained from family Liliaceae, five of them ( 1 , 3 , 5 , 7 and 9 ) were first reported in genus Polygonatum , while one compound ( 24 ) was first identified in this species. The results indicated that the proposed method was an efficient and sensitive approach to explore polyphenolic antioxidants from complex natural products. [ABSTRACT FROM AUTHOR]

[Display omitted] • [Ch]Cl in aqueous-ethanolic mixtures at 50% improved extraction from ∼7–29 mg/g to ∼35 mg/g. • IL aqueous mixtures at 75% presented the best extraction yield (∼66 mg/g) • Aqueous mixtures favored extraction performance and a more cost-efficient extraction. • Low-cost IL/DES are promising sustainable solvents alternatives over conventional. Mate leaves are highly appreciated in south and central America as food ingredient for tea preparation. Their nutritional importance, due to their high content of polyphenols and other nutraceuticals, has been drawing attention worldwide, especially to produce extracts and biopharmaceuticals. However, the extraction of such nutraceuticals using conventional processes/solvents might impact their profile/concentration. Ionic liquids (ILs) and deep eutectic solvents (DES) have been recognized as green solvents, and more recently the naturally-derived have stood out. In this work, we investigated the use of bioethanol, cholinium chloride ([Ch]Cl), Ch-based DES and less expensive protic ILs derived from acetic acid, in aqueous systems at different concentrations, as potential sustainable alternatives over conventional solvents and more expensive aprotic ILs for the extraction of polyphenols from mate leaves. Simply adding the [Ch]Cl in aqueous-ethanolic mixtures at 50% improved extraction efficiency (∼35 mg/g) in comparison to conventional solvents (∼7–29 mg/g). However, IL (∼41–66 mg/g) and DES (∼47–55 mg/g) systems presented better performance, being the former presenting the best results at 75% (∼66 mg/g). The extraction yield was also related to water concentration, which is interesting to reduce viscosity and IL/DES cost for a more cost-efficient extraction and was also supported by results obtained using COSMO-SAC. Therefore, the low-cost protic IL and DES are promising sustainable solvent alternatives over conventional solvents/ILs for extraction of polyphenols from mate leaves. [ABSTRACT FROM AUTHOR]

Abstract: Ischemia/reperfusion injury ends up in the cascade of excitotoxic stimulation of superoxide and nitric oxide formation leading to the generation of highly reactive products, including peroxinitrite and hydroxyl radical, which are capable of damaging lipids, proteins and DNA. Several polyphenolic compounds scavenge the radicals and protect from injury. 5,7,3′,4′,5′-pentahydroxy dihdroflavanol-3-O-(2″-O-galloyl)-β-d-glucopyranoside (AP1), a polyphenolic compound, isolated from Anogeissus pendula Edgew was tested for its neuroprotective effect in transient focal cerebral ischemia in rats. Transient focal cerebral ischemia was produced by middle cerebral artery occlusion for 2h for studying infarct volume, brain edema, apoptosis and oxidative stress. AP1 was tested for in vitro protection from glutamate and hydrogen peroxide-induced damage to Neuro-2a cells by MTT assay. It was also tested for its in vitro antioxidant, lipid peroxidation inhibition, NO scavenging and cyclooxygenase inhibitory activities. AP1 treatment (30mg/kg i.p.) before reperfusion injury (0h) significantly reduced the infarct volume, cerebral edema, number of apoptotic cells in penumbra and neurobehavioural abnormality score and lipid peroxidation, protein carbonyl levels and total thiols in brain. Increased catalase activity and NOx levels in ischemic animals were significantly reduced by AP1 treatment. AP1 (3µg/ml) protected Neuro-2a cells to H2O2 and glutamate-induced damage. In in vitro studies, AP1 was found to possess reducing and NO scavenging activities. It also reduced lipid peroxidation and inhibited cyclooxygenase activity (cyclooxygenase-1 and cyclooxygenase-2). AP1 can be used as a neuroprotective agent in stroke as it reduced apoptosis and found to be a good antioxidant and anti-inflammatory compound. [Copyright &y& Elsevier]

Abstract: Biological systems are frequently exposed to excessive reactive oxygen species, causing a disturbance in the cells natural antioxidant defence systems and resulting in damage to all biomolecules, including nucleic acids. In fact, oxidative DNA damage is described as the type of damage most likely to occur in neuronal cells. In this study, three polyphenolic compounds, luteolin, quercetin and rosmarinic acid, were investigated for their protective effects against oxidative DNA damage induced in PC12 cells, a neuronal cell model. Although luteolin and quercetin prevented the formation of strand breaks to a greater extent than rosmarinic acid, this last one presented the highest capacity to repair strand breaks formation. In addition, rosmarinic acid was the only compound tested that increased the repair of oxidized nucleotidic bases induced with the photosensitizer compound [R]-1-[(10-chloro-4-oxo-3-phenyl-4H-benzo[a]quinolizin-1-yl) carbonyl]-2-pyrrolidine-methanol (Ro 19-8022). The activity of repair enzymes was indicated by the in vitro base excision repair assay, using a cell-free extract obtained from cells previously treated with the compounds to incise DNA. The protective effect of rosmarinic acid was further confirmed by the increased expression of OGG1 repair gene, observed through real time RT-PCR. The data obtained is indicative that rosmarinic acid seems to act on the intracellular mechanisms responsible for DNA repair, rather than by a direct effect on reactive oxygen species scavenging, as deducted from the effects observed for luteolin and quercetin. Therefore, these results suggest the importance of these polyphenols, and in particular rosmarinic acid, as protectors of oxidative stress-induced DNA damage that commonly occurs in several pathological conditions, such as neurodegenerative diseases. [Copyright &y& Elsevier]

Abstract: Vacuum microwave-assisted extraction (VMAE), in which microwave-assisted extraction (MAE) was performed in vacuum, was specially designed and applied for the extraction of polyphenolic compounds and pigments from Chinese herbs. The extraction conditions including solid/liquid ratio, extraction time, extraction temperature and degree of vacuum were optimized. Subsequently, VMAE, MAE, and conventional heating reflux extraction (HRE) were evaluated with resveratrol and emodin extraction from Rhizma Polygoni Cuspidati, myricetin and quercetin extraction from Myrica rubra leaves, and safflomin A extraction from Flos Carthami. In addition, the different microstructures of those rhizome, leaf, and flower samples were investigated before and after extraction. It was obvious that the extraction yields of resveratrol, myricetin and safflomin A (thermosensitive compounds) with VMAE were higher than that with MAE or HRE by increments of 6.4–9.4% and 7.9–29.5%, respectively. In contrast, there was no obvious difference among the extraction yields for emodin and quercetin (thermo-stable compounds) with VMAE, MAE and HRE, except that the solvent consumption in VMAE was decreased. The results suggest that VMAE is a good alternative for the extraction of polyphenolic compounds and pigments, especially thermosensitive compounds, from Chinese herbs. [Copyright &y& Elsevier]

Abstract: We report here the total synthesis of quebecol, a new polyphenolic compound with potential applications recently isolated from maple syrup and produced during the condensation of the tree acer saccharum’s sap. The synthetic approach we developed involves, as key steps, the formation of a dibromoalkene from an α-ketoester precursor followed by a double Suzuki–Miyaura reaction to unite the three aromatic rings of the target compound on a tetrasubstituted olefin precursor. Our methodology is an efficient pathway to the target compound and leads the way for future analogs. [Copyright &y& Elsevier]