In the field of non‐fullerene organic solar cells (OSCs), compared to the rapid development of non‐fullerene acceptors, the progress of high‐performance donor polymers is relatively slow. The ...property and performance of donor polymers in OSCs are often sensitive to the molecular weight of the polymers. In this study, a chlorinated donor polymer named D18‐Cl is reported, which can achieve high performance with a wide range of polymer molecular weight. The devices based on D18‐Cl show a higher open‐circuit voltage (VOC) due to the slightly deeper energy levels and an outstanding short‐circuit current density (JSC) owing to the appropriate long periods of blend films and less (6,6‐phenyl‐C71‐butyric acid methyl ester) (PC71BM) in mixed domains, leading to the higher efficiency of 17.97% than those of the D18‐based devices (17.21%). Meanwhile, D18‐Cl can achieve high efficiencies (17.30–17.97%) when its number‐averaged molecular weight (Mn) is ranged from 45 to 72 kDa. In contrast, the D18‐based devices only exhibit relatively high efficiencies in a narrow Mn range of ≈70 kDa. Such property and performance make D18‐Cl a promising donor polymer for scale‐up and low‐cost production.
In this study, a chlorinated polymer named D18‐Cl is designed and synthesized, leading to highly efficient (near 18%) organic solar cells, yet whose performance is insensitive to its molecular weight. These advantages make D18‐Cl a more promising donor polymer than previously reported polymer D18 for scale‐up and low‐cost production.
Central π‐core engineering of non‐fullerene small molecule acceptors (NF‐SMAs) is effective in boosting the performance of organic solar cells (OSCs). Especially, selenium (Se) functionalization of ...NF‐SMAs is considered a promising strategy but the structure‐performance relationship remains unclear. Here, we synthesize two isomeric alkylphenyl‐substituted selenopheno3,2‐bthiophene‐based NF‐SMAs named mPh4F‐TS and mPh4F‐ST with different substitution positions, and contrast them with the thieno3,2‐bthiophene‐based analogue, mPh4F‐TT. When placing Se atoms at the outer positions of the π‐core, mPh4F‐TS shows the most red‐shifted absorption and compact molecular stacking. The PM6 : mPh4F‐TS devices exhibit excellent absorption, high charge carrier mobility, and reduced energy loss. Consequently, PM6 : mPh4F‐TS achieves more balanced photovoltaic parameters and yields an efficiency of 18.05 %, which highlights that precisely manipulating selenium functionalization is a practicable way toward high‐efficiency OSCs.
Two region‐specific selenium‐based non‐fullerene acceptors flanking conjugated side chains are compared with their sulfur‐based analogue. mPh4F‐TS with selenium at the outer positions show the most rigid skeleton, red‐shifted absorption and compact stacking. The PM6 : mPh4F‐TS organic solar cells exhibit the lowest energetic disorders, the highest charge carrier mobility and the best photon response, affording a top‐ranking efficiency of >18 %.
Side-chain engineering has been demonstrated as an effective method for fine-tuning the optical, electrical, and morphological properties of organic semiconductors toward efficient organic solar ...cells (OSCs). In this work, three isomeric non-fullerene small molecule acceptors (SMAs), named BTP-4F-T2C8, BTP-4F-T2EH and BTP-4F-T3EH, with linear and branched alkyl chains substituted on the
α
or
β
positions of thiophene as the side chains, were synthesized and systematically investigated. The results demonstrate that the size and substitution position of alkyl side chains can greatly affect the electronic properties, molecular packing as well as crystallinity of the SMAs. After blending with donor polymer D18-Cl, the prominent device performance of 18.25% was achieved by the BTP-4F-T3EH-based solar cells, which is higher than those of the BTP-4F-T2EH-based (17.41%) and BTP-4F-T2C8-based (15.92%) ones. The enhanced performance of the BTP-4F-T3EH-based devices is attributed to its stronger crystallinity, higher electron mobility, suppressed biomolecular recombination, and the appropriate intermolecular interaction with the donor polymer. This work reveals that the side chain isomerization strategy can be a practical way in tuning the molecular packing and blend morphology for improving the performance of organic solar cells.
Sweet tea (Lithocarpus polystachyus Rehd.) has been consumed as herbal tea to prevent and manage diabetes for a long time. Recent studies indicate that sweet tea is rich in a variety of bioactive ...compounds, especially a class of nonclassical flavonoids, dihydrochalcones. In order to provide a better understanding of sweet tea and its main dihydrochalcones on human health, this review mainly summarizes related literature in the recent ten years, with the potential molecular mechanisms emphatically discussed. Phlorizin, phloretin, and trilobatin, three natural sweeteners, are the main dihydrochalcones in sweet tea. In addition, sweet tea and its dihydrochalcones exhibit plenty of health benefits, such as antioxidant, anti-inflammatory, antimicrobial, cardioprotective, hepatoprotective, antidiabetic, and anticancer effects, which are associated with the regulation of different molecular targets and signaling pathways. Therefore, sweet tea, as a rare natural source of dihydrochalcones, can be processed and developed into nutraceuticals or functional foods, with the potential application in the prevention and management of certain chronic diseases.
In recent years, obesity has become a global public health issue. It is closely associated with the occurrence of several chronic diseases, such as diabetes and cardiovascular diseases. Some edible ...and medicinal plants show anti-obesity activity, such as fruits, vegetables, spices, legumes, edible flowers, mushrooms, and medicinal plants. Numerous studies have indicated that these plants are potential candidates for the prevention and management of obesity. The major anti-obesity mechanisms of plants include suppressing appetite, reducing the absorption of lipids and carbohydrates, inhibiting adipogenesis and lipogenesis, regulating lipid metabolism, increasing energy expenditure, regulating gut microbiota, and improving obesity-related inflammation. In this review, the anti-obesity activity of edible and medicinal plants was summarized based on epidemiological, experimental, and clinical studies, with related mechanisms discussed, which provided the basis for the research and development of slimming products. Further studies should focus on the exploration of safer plants with anti-obesity activity and the identification of specific anti-obesity mechanisms.
Many harmful substances have been found in foods, such as heavy metals, organic pollutants, pesticides and antibiotics, and food additives are widely used in the industry. Recent studies showed that ...these substances could affect the composition and diversity of gut microbiota, which plays important roles in health and diseases of host. Thus, these substances could show toxicities through disrupting the homeostasis of gut microbiota. On the other hand, some dietary bioactive compounds were found to restore the dysbiosis of gut microbiota. Therefore, certain dietary natural products could relieve the toxicities of harmful substances on human beings via regulating gut microbiota.
In this review, the influences of several harmful substances and additives on gut microbiota are summarized, and protective effects of dietary bioactive compounds are also discussed. It is hoped to provide a better understanding of dietary natural products to reduce toxicities of harmful substances on human beings by targeting gut microbiota. Considering wide existence of harmful substances and additives in foods, this topic would attract more attention in the future to protect human health.
Gut microbiota plays a vital role in diseases and health based on human and most animal studies. Some gut microbes, such as Bifidobacterium and Lactobacillus, could synthesize various essential nutrients for human growth. In addition, some Bifidobacterium strains, Clostridium tyrobutyricum, and Lactobacillus paracasei, were associated with anti-inflammatory property. Moreover, Anaerostipes, Corynebacterium, Dorea, Roseburia, Ruminococcus, and Turicibacter, were also related to inflammation. Harmful substances, such as atrazine, polychlorinated biphenyl, and heavy metals, were mainly ingested through the contaminated water and foods, could disturb gut microbiota and be detrimental to health. Besides, gut microbiota dysbiosis was potentially caused by some food additives, which altered gut barrier and activated the immune response. On the other hand, some dietary natural products, such as melatonin, wheat bran, pectin, chlorogenic acid, and isoorientin, showed beneficial efficacy through restoring dysbiosis of gut microbiota caused by harmful substances. In the future, more attention should be paid to the exploration of more dietary plants and their components with gut microbiota regulatory effects in order to reduce the toxicities of harmful substances and protect human health.
•The roles of gut microbiota in diseases and health are summarized.•The effects of contaminants and additives on gut microbiota are discussed.•The effects of bioactive compounds on gut microbiota dysbiosis are highlighted.•Gut microbiota is a promising target to reduce toxicities of harmful substance.
Effects and mechanisms of tea on obesity Xu, Xiao-Yu; Zhao, Cai-Ning; Li, Bang-Yan ...
Critical reviews in food science and nutrition,
2023, Letnik:
63, Številka:
19
Journal Article
Recenzirano
Obesity has become a global health concern. It increases the risk of several diseases, such as type 2 diabetes mellitus, nonalcoholic fatty liver disease, and certain cancers, which threatens human ...health and increases social economic burden. As one of the most consumed beverages, tea contains various phytochemicals with potent bioactive properties and health-promoting effects, such as antioxidant, immune-regulation, cardiovascular protection and anticancer. Tea and its components are also considered as potential candidates for anti-obesity. Epidemiological studies indicate that regular consumption of tea is beneficial for reducing body fat. In addition, the experimental studies demonstrate that the potential anti-obesity mechanisms of tea are mainly involved in increasing energy expenditure and lipid catabolism, decreasing nutrient digestion and absorption as well as lipid synthesis, and regulating adipocytes, neuroendocrine system and gut microbiota. Moreover, most of clinical studies illustrate that the intake of green tea could reduce body weight and alleviate the obesity. In this review, we focus on the effect of tea and its components on obesity from epidemiological, experimental, and clinical studies, and discuss their potential mechanisms.
Cancer is a severe public health problem. Resveratrol is a famous natural compound that has various bioactivities, such as antioxidant, anti-inflammatory, antidiabetic and antiaging activities. ...Especially, resveratrol could prevent and treat various cancers, such as oral, thyroid, breast, lung, liver, pancreatic, gastric, colorectal, bladder, prostate and ovarian cancers. The underlying mechanisms have been widely studied, such as inhibiting cell proliferation, suppressing metastasis, inducing apoptosis, stimulating autophagy, modulating immune system, attenuating inflammation, regulating gut microbiota and enhancing effects of other anticancer drugs. In this review, we summarize effects and mechanisms of resveratrol on different cancers. This paper is helpful to develop resveratrol, crude extract containing resveratrol, or foods containing resveratrol into functional food, dietary supplements or auxiliary agents for prevention and management of cancers.
Dietary intake of caffeine has significantly increased in recent years, and beneficial and harmful effects of caffeine have been extensively studied. This paper reviews antioxidant and ...anti-inflammatory activities of caffeine as well as its protective effects on cardiovascular diseases, obesity, diabetes mellitus, cancers, and neurodegenerative and liver diseases. In addition, we summarize the side effects of long-term or excessive caffeine consumption on sleep, migraine, intraocular pressure, pregnant women, children, and adolescents. The health benefits of caffeine depend on the amount of caffeine intake and the physical condition of consumers. Moderate intake of caffeine helps to prevent and modulate several diseases. However, the long-term or over-consumption of caffeine can lead to addiction, insomnia, migraine, and other side effects. In addition, children, adolescents, pregnant women, and people who are sensitive to caffeine should be recommended to restrict/reduce their intake to avoid potential adverse effects.
Cardiovascular diseases (CVDs) have gained increasing attention because of their high prevalence and mortality worldwide. Epidemiological studies revealed that intake of fruits, vegetables, nuts, and ...cereals could reduce the risk of CVDs, and their antioxidants are considered as the main contributors. Moreover, experimental studies showed that some antioxidant natural products and their bioactive compounds exerted beneficial effects on the cardiovascular system, such as polyphenols, polysaccharides, anthocyanins, epigallocatechin gallate, quercetin, rutin, and puerarin. The mechanisms of action mainly included reducing blood pressure, improving lipid profile, ameliorating oxidative stress, mitigating inflammation, and regulating gut microbiota. Furthermore, clinical trials confirmed the cardiovascular-protective effect of some antioxidant natural products, such as soursop, beetroot, garlic, almond, and green tea. In this review, we summarized the effects of some antioxidant natural products and their bioactive compounds on CVDs based on the epidemiological, experimental, and clinical studies, with special attention paid to the relevant mechanisms and clinical trials.
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