The beneficial health effects of green tea amino acid l -theanine in animal models: Promises and prospects for human trials

Antidiabetic Potential of Tea and Its Active Compounds: From Molecular Mechanism to Clinical Evidence

Diabetes mellitus (DM) is a chronic endocrine disorder that poses a long-term risk to human health accompanied by serious complications. Common antidiabetic drugs are usually accompanied by side effects such as hepatotoxicity and nephrotoxicity. There is an urgent need for natural dietary alternatives for diabetic treatment. Tea (Camellia sinensis) consumption has been widely investigated to lower the risk of diabetes and its complications through restoring glucose metabolism homeostasis, safeguarding pancreatic β-cells, ameliorating insulin resistance, ameliorating oxidative stresses, inhibiting inflammatory response, and regulating intestinal microbiota. It is indispensable to develop effective strategies to improve the absorption of tea active compounds and exert combinational effects with other natural compounds to broaden its hypoglycemic potential. The advances in clinical trials and population-based investigations are also discussed. This review primarily delves into the antidiabetic potential and underlying mechanisms of tea active compounds, providing a theoretical basis for the practical application of tea and its active compounds against diabetes.

Biological Potential and Mechanisms of Tea's Bioactive Compounds in Tea: An Updated Review

BACKGROUND

Tea (Camellia sinensis) has a rich history and is widely consumed across many countries, and is categorized into green tea, white tea, oolong tea, yellow tea, black tea, and dark tea based on the level of fermentation. Based on a review of previous literature, the commonly recognized bioactive substances in tea include tea polyphenols, amino acids, polysaccharides, alkaloids, terpenoids, macro minerals, trace elements, and vitamins, which have been known to have various potential health benefits, such as anticancer, antioxidant, anti-inflammatory, anti-diabetes, and anti-obesity properties, cardiovascular protection, immune regulation, and control of the intestinal microbiota. Most studies have only pointed out the characteristics of tea's bioactivities, so a comprehensive summary of the pharmacological characteristics and mechanisms of tea's bioactivities and their use risks are vital.

AIM

of Review The aim of this paper is to summarize the bioactive substances of tea and their pharmacological characteristics and mechanisms, providing a scientific basis for the application of bioactive substances in tea and outlining future research directions for the study of bioactive substances in tea. Key Scientific Concepts of Review This review summarizes the main biologically active substances, pharmacological effects, and mechanisms and discusses the potential risks. It may help researchers to grasp more comprehensive progress in the study of tea bioactive substances to further promote the application of tea as a natural bioactive substance in the medical field.

L-Theanine adjunct to risperidone in the treatment of chronic schizophrenia inpatients: a randomized, double-blind, placebo-controlled clinical trial

RATIONALE

Inadequate responses to current schizophrenia treatments have accelerated research into novel therapeutic approaches.

OBJECTIVES

This study investigated the efficacy and tolerability of adjunctive L-theanine, an ingredient with neuroimmunomodulatory and neuroprotective properties, for chronic schizophrenia.

METHODS

Eighty chronic schizophrenia inpatients were equally assigned to receive risperidone (6 mg/day) plus either L-theanine (400 mg/day) or matched placebo in this 8-week, randomized, parallel-group, double-blind, placebo-controlled trial. The participants were assessed using the Positive and Negative Syndrome Scale (PANSS) by recording the results of subscales at baseline and weeks 4 and 8 to measure treatment efficacy. Additionally, the participants were assessed for the Hamilton Depression Rating Scale (HDRS) and adverse events, including the Extrapyramidal Symptom Rating Scale (ESRS).

RESULTS

Sixty patients, 30 in each group, were included in the analyses. All baseline demographic and clinical characteristics were comparable between the groups (p-values > 0.05). The reduction rates from baseline to endpoint in negative, general psychopathology, and total scores of PANSS were greater in the L-theanine group (p-values = 0.03, 0.01, and 0.04, respectively). Regarding general psychopathology scores, the reduction in the L-theanine group was also greater until week 4 (p-value < 0.01). The time × treatment interaction effect was significant on negative (p-value = 0.03), general psychopathology (p-value < 0.01), and total (p-value = 0.04) scores of PANSS, indicating additional improvements in the L-theanine group. The HDRS and side effects were comparable between the groups (p-values > 0.05).

CONCLUSIONS

L-Theanine adjunct to risperidone safely and tolerably outperformed adjunctive placebo for schizophrenia, and promising evidence indicated its effects on primary negative symptoms, which need to be scrutinized in further studies.

TRIAL REGISTRATION

The study protocol was registered and published prospectively in the Iranian Registry of Clinical Trials ( http://www.irct.ir ; registration number: IRCT20090117001556N133) on 2020-12-12.

The protective effect of L-theanine addition to a cryoprotectant on the storage viability of lactic acid bacteria

Lactic acid bacteria (LAB) that metabolize sugars to obtain energy and produce a large amount of lactate through the process are well known for their benefits. However, they can be used on a large scale only when good storage stability is guaranteed. The vitality and stability of several LAB strains were effectively protected in this investigation by L-theanine at 1% of the appropriate concentration (Lactiplantibacillus plantarum MG5023, Enterococcus faecium MG5232, Lactococcus lactis MG4668, Streptococcus thermophilus MG5140, and Bifidobacterium animalis subsp. lactis MG741). The inclusion of L-theanine as a protective agent significantly enhanced the viability of all strains throughout the freeze-drying process compared to that of the non-coated probiotics. The efficacy of L-theanine in improving bacterial stability and survivability was evaluated using accelerated stability tests, gastrointestinal (GI) tract survivability tests, and adhesion assays with intestinal epithelial cells. The cell surface was covered with substances including L-theanine, according to morphological findings, providing efficient defense against a variety of external stresses. Therefore, by exerting anti-freezing and anti-thawing properties, the adoption of L-theanine as a new and efficient protective agent may improve the stability and viability of a variety of probiotics.

Tea's anti-obesity properties, cardiometabolic health-promoting potentials, bioactive compounds, and adverse effects: A review focusing on white and green teas

Tea is one of the most commonly consumed beverages in the world. Morocco, Japan, and China have consumed green tea for centuries. White tea, which is a variety of green teas, is very popular in China and is highly revered for its taste. Presently, both teas are consumed in other countries around the world, even as functional ingredients, and novel research is constantly being conducted in these areas. We provide an update on the health benefits of white and green teas in this review, based on recent research done to present. After a general introduction, we focused on tea's anti-obesity and human health-promoting potential, adverse effects, and new approaches to tea and its bioactive compounds. It has been found that the health benefits of tea are due to its bioactive components, mainly phenolic compounds. Of these, catechins are the most abundant. This beverage (or its extracts) has potential anti-inflammatory and antioxidant properties, which could contribute to body weight control and the improvement of several chronic diseases. However, some studies have mentioned the possibility of toxic effects; therefore, reducing tea consumption is a good idea, especially during the last trimester of pregnancy. Additionally, new evidence will provide insight into the possible effects of tea on the human gut microbiota, and even on the viruses responsible for SARS-CoV-2. A beverage such as this may favor beneficial gut microbes, which may have important implications due to the influence of gut microbiota on human health.

Over the Counter Supplements for Memory: A Review of Available Evidence

In 2021, the Global Brain Health Supplement Industry Market size was valued at US$7.6 billion. It is predicted to increase to US$15.59 billion by 2030. Memory and its enhancement are a segment of the market that comprised the highest global revenue share in 2021. In the USA alone, dietary supplement sales reached US$18 billion in 2018. The US Food and Drug Administration (FDA) does not have the authority to approve dietary supplements' safety, effectiveness, or labeling before products go on the market. The FDA often does not even review supplements before they go to market. Supplement manufacturers are thus responsible for ensuring their products are safe and that their claims are truthful. An extensive review of current supplements on the market was performed by surveying memory products for sale at local and national pharmacies and grocery stores. A list of 103 supplements was compiled and the ingredients in these memory supplements were reviewed. The 18 most common ingredients in these supplements were identified. Each of the supplements included at least one of the 18 most common ingredients. Scientific data relative to these ingredients and their effect on memory was searched using PubMed and Cochrane library databases. Currently, there is no compelling evidence for use of apoaequorin, coenzyme Q10, coffee extracts, L-theanine, omega-3 fatty acids, vitamin B6, vitamin B9, or vitamin B12 supplementation for memory. On the other hand, there is some current evidence for memory benefit from supplementation with ashwagandha, choline, curcumin, ginger, Lion's Mane, polyphenols, phosphatidylserine, and turmeric. There are current studies with mixed results regarding the benefit of carnitine, gingko biloba, Huperzine A, vitamin D, and vitamin E supplementation for memory. Dietary supplements geared toward improving cognition are a billion-dollar industry that continues to grow despite lacking a solid scientific foundation for their marketing claims. More rigorous studies are needed relative to the long-term use of these supplements in homogenous populations with standardized measurements of cognition. Health care providers need to be aware of any and all supplements their older adult patients may be consuming and be educated about their side effects and interactions with prescription medications. Lastly, the FDA needs to take an active position relative to monitoring marketed supplements regarding safety, purity and claims of efficacy.

Tea intake or consumption and the risk of dementia: a meta-analysis of prospective cohort studies

Purpose

Dementia affects as many as 130 million people, which presents a significant and growing medical burden globally. This meta-analysis aims to assess whether tea intake, tea consumption can reduce the risk of dementia, Alzheimer's disease (AD) and Vascular dementia (VD).

Patients and methods

Cochrane Library, PubMed and Embase were searched for cohort studies from inception to November 1, 2022. The Newcastle Ottawa Quality Assessment Scale (NOS) was applied to evaluate the risk of bias of the included studies. We extracted the data as the relative risks (RRs) for the outcome of the interest, and conducted the meta-analysis utilizing the random effect model due to the certain heterogeneity. Sensitivity analysis were performed by moving one study at a time, Subgroup-analysis was carried out according to different ages and dementia types. And the funnel plots based on Egger's and Begger's regression tests were used to evaluate publication bias. All statistical analyses were performed using Stata statistical software version 14.0 and R studio version 4.2.0.

Results

Seven prospective cohort studies covering 410,951 individuals, which were published from 2009 and 2022 were included in this meta-analysis. The methodological quality of these studies was relatively with five out of seven being of high quality and the remaining being of moderate. The pooling analysis shows that the relationship between tea intake or consumption is associated with a reduced risk of all-cause dementia (RR = 0.71, 95% CI [0.57-0.88], I² = 79.0%, p < 0.01). Further, the subgroup-analysis revealed that tea intake or consumption is associated with a reduced risk of AD (RR = 0.88, 95% CI [0.79-0.99], I² = 52.6%, p = 0.024) and VD (RR = 0.75, 95% CI [0.66-0.85], I = 0.00%, p < 0.001). Lastly, tea intake or consumption could reduce the risk of all-cause dementia to a greater degree among populations with less physical activity, older age, APOE carriers, and smokers.

Conclusion

Our meta-analysis demonstrated that tea (green tea or black tea) intake or consumption is associated with a significant reduction in the risk of dementia, AD or VD. These findings provide evidence that tea intake or consumption should be recognized as an independent protective factor against the onset of dementia, AD or VD.

Establishment of an efficient transformation system and its application in regulatory mechanism analysis of biological macromolecules in tea plants

Tea (Camellia sinensis), one of the most important beverage crops originated from China and is now cultivated worldwide, provides numerous secondary metabolites that account for its health benefits and rich flavor. However, the lack of an efficient and reliable genetic transformation system has seriously hindered the gene function investigation and precise breeding of C. sinensis. In this study, we established a highly efficient, labor-saving, and cost-effective Agrobacterium rhizogenes-mediated hairy roots genetic transformation system for C. sinensis, which can be used for gene overexpression and genome editing. The established transformation system was simple to operate, bypassing tissue culture and antibiotic screening, and only took two months to complete. We used this system to conduct function analysis of transcription factor CsMYB73 and found that CsMYB73 negatively regulates L-theanine synthesis in tea plant. Additionally, callus formation was successfully induced using transgenic roots, and the transgenic callus exhibited normal chlorophyll production, enabling the study of the corresponding biological functions. Furthermore, this genetic transformation system was effective for multiple C. sinensis varieties and other woody plant species. By overcoming technical obstacles such as low efficiency, long experimental periods, and high costs, this genetic transformation will be a valuable tool for routine gene investigation and precise breeding in tea plants.

L-theanine attenuates nicotine reward and withdrawal signs in mice

BACKGROUND

L-theanine, 2-amino-4-(ethylcarbamoyl) butyric acid, an amino acid detected in green tea leaves, is used as a dietary supplement to attenuate stress and enhance mood and cognition. Furthermore, L-theanine induces anxiolytic effects in humans. Recently, L-theanine was reported to reduce morphine physical dependence in primates, suggesting the potential usefulness of L-theanine for drug dependence intervention.

OBJECTIVE

The aim of this study is to determine whether L-theanine attenuates nicotine-withdrawal (somatic and affective signs) and nicotine reward in mice. We also investigated the effects of L-theanine on nicotinic receptors binding and function.

METHODS

ICR male mice rendered dependent to nicotine through implanted subcutaneous osmotic minipumps for 14 days undertook precipitated nicotine withdrawal by mecamylamine on day 15. Anxiety-like behaviors using LDB, somatic signs observation and hot plate latency were assessed consecutively after treatment with L-theanine. Furthermore, we examined the effect of L-theanine on acute nicotine responses and nicotine conditioned reward in mice and on expressed nicotinic receptors in oocytes.

KEY FINDINGS

L-theanine reduced in a dose-dependent manner anxiety-like behavior, hyperalgesia and somatic signs during nicotine withdrawal. Also, L-theanine decreased the nicotine CPP, but it did not affect the acute responses of nicotine. Finally, L-theanine did not alter the binding or the function of expressed α4β2 and α7 nAChRs.

CONCLUSION

Our results support the potential of L-theanine as a promising candidate for treating nicotine dependence.

How does l-theanine treatment affect the levels of serum and hippocampal BDNF, insulin and adipocytokines in diabetic rats?

BACKGROUND

Diabetes Mellitus (DM), a metabolic disease characterized by the increased blood glucose level, insulin deficiency or ineffectiveness, may cause structural and functional disorders in the brain. l-Theanine (LTN) has the relaxing, psychoactive, antidepressant, anti-inflammatory and antinecrotic properties, and regulates the functions of hippocampus (HP) in brain. In the present study, the aim was to identify the effects LTN on the levels of BDNF, insulin and adipocytokines (TNF-α, leptin, adiponectin and resistin) in both HP and serum of diabetic rats.

METHODS

32 male Wistar rats were divided into four groups (n = 8/group): Control, LTN, DM and DM + LTN. Diabetes was induced by by nicotinamide/streptozotocin. 200 mg/kg/day LTN treatment was applied for 28 days. The serum and hippocampal levels of the parameters were determined by using commercial ELISA kits. Additionally, HP tissues examined histopathologically.

RESULTS

LTN treatment significantly decreased leptin and adiponectin levels in HP tissues in diabetic rats (p < 0.05). Although it decreased the insulin level in both serum and HP, this was not statistically significant. No significant effect on other parameters was observed (p > 0.05). In histopathological analysis, although the damage was reduced by LTN in all sections of HP, this change was significant mainly in CA3 region (p < 0.05).

CONCLUSION

It was concluded that LTN has the ability to reduce hippocampal degeneration and modulates adipocytokines in diabetic rats.

Special tea products featuring functional components: Health benefits and processing strategies

The functional components in tea confer various potential health benefits to humans. To date, several special tea products featuring functional components (STPFCs) have been successfully developed, such as O-methylated catechin-rich tea, γ-aminobutyric acid-rich tea, low-caffeine tea, and selenium-rich tea products. STPFCs have some unique and enhanced health benefits when compared with conventional tea products, which can meet the specific needs and preferences of different groups and have huge market potential. The processing strategies to improve the health benefits of tea products by regulating the functional component content have been an active area of research in food science. The fresh leaves of some specific tea varieties rich in functional components are used as raw materials, and special processing technologies are employed to prepare STPFCs. Huge progress has been achieved in the research and development of these STPFCs. However, the current status of these STPFCs has not yet been systematically reviewed. Here, studies on STPFCs have been comprehensively reviewed with a focus on their potential health benefits and processing strategies. Additionally, other chemical components with the potential to be developed into special teas and the application of tea functional components in the food industry have been discussed. Finally, suggestions on the promises and challenges for the future study of these STPFCs have been provided. This paper might shed light on the current status of the research and development of these STPFCs. Future studies on STPFCs should focus on screening specific tea varieties, identifying new functional components, evaluating health-promoting effects, improving flavor quality, and elucidating the interactions between functional components.

Green Extraction Techniques for the Determination of Active Ingredients in Tea: Current State, Challenges, and Future Perspectives

In recent years, the scientific community has turned its attention to the further study and application of green chemistry as well as to sustainable development in reducing the consumption of raw materials, solvents, and energy. The application of green chemistry aims to ensure the protection of the environment and to also, consequently, improve the quality of human life. It offers several benefits, both socially and economically. In the last few decades, new alternative non-conventional green extraction methodologies have been developed for the purposes of the extraction of active ingredient compounds from various raw products. The main objective of this literature review is to present the current knowledge and future perspectives regarding the green extraction of tea species in respect of the isolation of safe active biomolecules, which can be used as commercially available products—both as dietary supplements and pharmaceutical formulations. More specifically, in this literature review, the intention is to investigate several different extraction techniques, such as ultrasonic-assisted extraction, ultrasonic-assisted extraction with DESs, the microwave assisted-extraction method, and the reflux method. These are presented in respect of their role in the isolation of bioactive molecules regarding different tea species. Furthermore, following the literature review conducted in this study, the commonly used green extraction methods were found to be the ultrasound-assisted method and the microwave-assisted method. In addition to these, the use of a green solvent, in regard to its role in the maximum extraction yield of active ingredients in various species of tea, was emphasized. Catechins, alkaloids (such as caffeine), gallic acid, and flavonoids were the main extracted bioactive molecules that were isolated from the several tea species. From this literature review, it can be demonstrated that green tea has been widely studied at a rate of 52% in respect of the included research studies, followed by black tea at 26%, as well as white tea and oolong tea at 11% each. Regarding the determination of the bioactive molecules, the most utilized analytical method was found in the combination of high-performance liquid chromatography (HPLC) with a photodiode array detector (PDA) and mass spectrophotometry (MS) at a usage rate of about 80%. This method was followed by the utilization of UPLC and GC at 12% and 8%, respectively. In the future, it will be necessary to study the combination of green extraction techniques with other industry strategies, such as an encapsulation at the micro and nano scale, for the purposes of preparing stable final products with antioxidant properties where, finally, they can be safely consumed by humans.

Can habitual tea drinking be an effective approach against age-related neurodegenerative cognitive disorders: A systematic review and meta-analysis of epidemiological evidence

Our present knowledge about the efficacy of tea consumption in improving age-related cognitive disorders is incomplete since previous epidemiological studies provide inconsistent evidence. This unified systematic review and meta-analysis based on updated epidemiological cohort studies and randomized controlled trials (RCTs) evidence aimed to overcome the limitations of previous reviews by examining the efficacy of distinct types of tea consumption. PubMed, Embase, and MEDLINE were searched up to May 20, 2022, and 23 cohorts and 12 cross-sectional studies were included. Random-effects meta-analyses were conducted to obtain pooled RRs or mean differences with 95% CIs. The pooled RRs of the highest versus lowest tea consumption categories were 0.81 (95% CIs: 0.75-0.88) and 0.69 (95% CIs: 0.61-0.77), respectively. The pooled mean difference of four included RCTs revealed a beneficial effect of tea on cognitive dysfunction (MMSE ES: 1.03; 95% CI, 0.14-1.92). Subgroup analyses further demonstrated that green and black tea intake was associated with a lower risk of cognitive disorders in eastern countries, especially in women. The evidence quality was generally low to moderate. The present review provides insight into whether habitual tea consumption can be an effective approach against age-related neurodegenerative cognitive disorders and summarizes potential mechanisms based on currently published literature.

Combining Topical and Oral Botanicals for Skin Redness, Pigmentation, Sleep, and Mood: A Randomized Controlled Study

External and internal stressors have been found to adversely affect skin health and overall wellness. There is growing interest in the use of anti-inflammatory and antioxidant plant-derived ingredients, such as ashwagandha, saffron, l-theanine, and tocopherol, to mitigate the impact of these stressors. In this study, we evaluate the effectiveness of oral and topical products (InnerCalm and SuperCalm, respectively) that contain naturally derived ingredients on skin redness, skin pigmentation, sleep, and mood in healthy females with Fitzpatrick skin type 1−4 and self-perceived sensitive skin. Subjects were randomized to an oral (oral group), a topical (topical group), or a combination of both the oral and topical interventions (combined group). Standardized photography-based image analysis was used to assess skin redness and pigment. Self-assessments of mood and sleep were measured with the abbreviated profile of mood states (POMS) questionnaire, and the Pittsburgh sleep-quality index (PSQI), respectively. Assessments were made at the baseline, 1-week, 4-weeks, and 8-weeks of the intervention. The average facial redness decreased in the topical group at 8-weeks (p < 0.001) and in the combined group at 4-weeks (p < 0.05) and 8-weeks (p < 0.001), relative to the baseline. The average facial pigmentation decreased in the oral (p < 0.05) and combined (p < 0.05) cohorts at 8-weeks, relative to the baseline. The oral group exhibited an improvement in sleep quality at 1-week relative to the baseline (p < 0.05) and at 8-weeks relative to the baseline (p < 0.05). Finally, the combined group demonstrated improvement in fatigue (p < 0.01) and confusion (p < 0.05) at 8-weeks relative to the baseline, though total mood disturbance increased in all 3 groups over the course of the study. Measured outcomes relating to mood may be confounded with the timing of the study, which ran during the COVID pandemic. Overall, we demonstrate the role of oral and topical herbs and of nutraceuticals for skin health and wellness. Further research will be needed to elucidate synergistic effects in oral and topical combination regimens.

Multi-Metabolomics Coupled with Quantitative Descriptive Analysis Revealed Key Alterations in Phytochemical Composition and Sensory Qualities of Decaffeinated Green and Black Tea from the Same Fresh Leaves

The supercritical CO₂-based decaffeination (SCD) method can be used to prepare decaffeinated tea, but its overall effect on the phytochemicals, volatiles, and sensory qualities of green and black teas is still unclear, and its suitability to prepare decaffeinated green and black teas still needs to be compared. This study revealed the effect of SCD on phytochemicals, volatiles, and sensory qualities in black and green tea prepared from the same tea leaves, and compared the suitability of preparing decaffeinated green and black teas using SCD. The results showed that the SCD could remove 98.2 and 97.1% of the caffeine in green and black tea, respectively. However, it can cause further losses of phytochemicals in green and black teas, specifically the loss of epigallocatechin gallate, epigallocatechin, epicatechin gallate, and gallocatechin gallate in green tea and the loss of theanine and arginine in green and black teas. After the decaffeination, both green and black teas lost some volatiles but also generated new volatiles. Especially, the fruit/flower-like aroma, ocimene, linalyl acetate, geranyl acetate, and D-limonene, were generated in the decaffeinated black tea, while herbal/green-like aroma, β-cyclocitral, 2-ethylhexanol, and safranal, were generated in the decaffeinated green tea. The overall acceptance of decaffeinated green tea decreased due to the substantial reduction in bitterness and astringency, while the overall acceptance of decaffeinated black tea significantly increased. Therefore, SCD is more suitable for the preparation of decaffeinated black tea.

Physicochemical, antioxidant and sensory properties of Mango Sorbet containing L-theanine as a potential functional food product

The non-proteinous amino acid L-theanine (L-THE) is associated with a range of health benefits including improvements in immune function, cardiovascular outcomes and cognition. The aims of this study were to develop a food product (mango sorbet; ms-L-THE) containing physiologically relevant doses of L-THE (0.2/100 g w/w) and determine its antioxidant, physicochemical and sensory properties in comparison to a mango sorbet without L-THE (ms). Total phenolic and flavanol content, and antioxidant analysis (DPPH, FRAP and ABTS) were determined spectrophotometrically. Both products were also evaluated for acceptability and likeability in healthy participants using the 9-point hedonic scale. Any differences that could be caused by the addition of L-THE were examined using the triangle test. Results indicated no significant differences between ms-L-THE and ms in taste of the products (p > 0.05), and the ms-L-THE was well received and accepted as a potential commercial product. Findings of the DPPH assay indicated significant difference between the two products (p < 0.05). In conclusion, we have successfully created a mango sorbet that contains a potentially physiologically relevant concentration of L-THE with antioxidant properties that could be used as a novel method of L-THE delivery to clinical and healthy populations.

Protein and Sport: Alternative Sources and Strategies for Bioactive and Sustainable Sports Nutrition

Nutrition and sport play an important role in achieving a healthy lifestyle. In addition to the intake of nutrients derived from the normal diet, some sport disciplines require the consumption of supplements that contribute positively to improved athletic performance. Protein intake is important for many aspects related to health, and current evidence suggests that some athletes require increased amounts of this nutrient. On the other hand, society's demand for more environmentally friendly products, focus on the search for alternative food sources more sustainable. This review aims to summarize the latest research on novel strategies and sources for greener and functional supplementation in sport nutrition. Alternative protein sources such as insects, plants or mycoproteins have proven to be an interesting substrate due to their high added value in terms of bioactivity and sustainability. Protein hydrolysis has proven to be a very useful technology to revalue by-products, such as collagen, by producing bioactive peptides beneficial on athletes performance and sport-related complications. In addition, it has been observed that certain amino acids from plant sources, as citrulline or theanine, can have an ergogenic effect for this target population. Finally, the future perspectives of protein supplementation in sports nutrition are discussed. In summary, protein supplementation in sports nutrition is a very promising field of research, whose future perspective lies with the search for alternatives with greater bioactive potential and more sustainable than conventional sources.

L-theanine protects rat kidney from D-galactose-induced injury via inhibition of the AGEs/RAGE signaling pathway

As the irreversible products of the non-enzymatic reduction of sugars and the amino groups of proteins or peptides, advanced glycation end products (AGEs) are metabolized and excreted via the kidneys. However, if AGEs are not metabolized, they are deposited in the kidneys and bind to AGE receptors (RAGE), which can induce various pathological changes, including oxidative stress, apoptosis, and inflammation. This study used the D-galactose (DG)-induced rat model to explore the potential role and mechanism of L-theanine in inhibiting AGEs/RAGE-related signaling pathways in renal tissues. L-theanine increased the activities of glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) while downregulating the contents of malondialdehyde (MDA) and AGEs in renal tissues induced by DG (P < 0.05). By inhibiting the upregulation of RAGE protein expression attributed to AGEs accumulation (P < 0.05), L-theanine downregulated phosphorylated nuclear factor (p-NF-κB (p65)), Bax, and cleaved-caspase-3 expression and increased Bcl-2 protein expression (P < 0.05), thereby alleviating the oxidative stress damage and reducing the inflammation and cell injury induced by DG. In addition, the Congo red staining section of renal tissue also showed that the natural product L-theanine can protect against AGEs-induced renal damage in DG-induced rat model.

Electronic Sensor Technologies in Monitoring Quality of Tea: A Review

Tea, after water, is the most frequently consumed beverage in the world. The fermentation of tea leaves has a pivotal role in its quality and is usually monitored using the laboratory analytical instruments and olfactory perception of tea tasters. Developing electronic sensing platforms (ESPs), in terms of an electronic nose (e-nose), electronic tongue (e-tongue), and electronic eye (e-eye) equipped with progressive data processing algorithms, not only can accurately accelerate the consumer-based sensory quality assessment of tea, but also can define new standards for this bioactive product, to meet worldwide market demand. Using the complex data sets from electronic signals integrated with multivariate statistics can, thus, contribute to quality prediction and discrimination. The latest achievements and available solutions, to solve future problems and for easy and accurate real-time analysis of the sensory-chemical properties of tea and its products, are reviewed using bio-mimicking ESPs. These advanced sensing technologies, which measure the aroma, taste, and color profiles and input the data into mathematical classification algorithms, can discriminate different teas based on their price, geographical origins, harvest, fermentation, storage times, quality grades, and adulteration ratio. Although voltammetric and fluorescent sensor arrays are emerging for designing e-tongue systems, potentiometric electrodes are more often employed to monitor the taste profiles of tea. The use of a feature-level fusion strategy can significantly improve the efficiency and accuracy of prediction models, accompanied by the pattern recognition associations between the sensory properties and biochemical profiles of tea.

Tremor and Rigidity in Patients with Parkinson's Disease: Emphasis on Epidemiology, Pathophysiology and Contributing Factors

Parkinson's disease (PD) is the second most prominent neurodegenerative movement disorder after Alzheimer's disease, involving 2-3% of the population aged above 65 years. This is mainly triggered by the depletion of dopaminergic neurons located in substantia nigra pars compacta (SNpc) in the region of basal ganglia. At present, diagnosis for symptoms of PD is clinical, contextual, unspecified and therapeutically incomprehensive. Analysis of various causes of PD is essential for an accurate examination of the disease. Among the different causes, such as tremors and rigidity, unresponsiveness to the current treatment approach contributes to mortality. In the present review article, we describe various key factors of pathogenesis and physiology associated with tremors and rigidity necessary for the treatment of PI (postural instability) in patients with PD. Additionally, several reports showing early tremor and rigidity causes, particularly age, cortex lesions, basal ganglia lesions, genetic abnormalities, weakened reflexes, nutrition, fear of fall, and altered biomechanics, have been explored. By summarizing the factors that contribute to the disease, histopathological studies can assess rigidity and tremor in PD. With a clear understanding of the contributing factors, various prospective studies can be done to assess the incidence of rigidity and tremors.

The future of high-quality Ceylon tea seems bleak in the face of climate change

Understanding the interactive effects and relationships between biochemical elements of tea leaves and the related factors, particularly climatic, cultivar, and geographic, is key for high-quality Ceylon tea production. The objectives of this study were to (1) investigate the effects of season × cultivar × agro-ecological regions (AERs) on the four tested biochemicals in fresh tea leaves, total polyphenol content (TPC), free sugar, protein, and theanine; (2) determine the relationships between, and develop a model to estimate, the biochemicals and their related factors; and (3) project the potential concentrations and distributions of four tested biochemicals in tea leaves with respect to the current and future climate. This study primarily uses inferential statistics via the Statistical Package for the Social Sciences (SPSS), cross-validation using R software, and the inverse distance weighting (IDW) approach in ArcGIS. The results demonstrate that the season, cultivar (Ceylon tea cultivars of TRI 2025 and TRI 4053), and AER and their interactions on biochemicals have significant effects (p < 0.05). The models derived in the regression analysis demonstrate the strong relationships between the independent variables and the biochemicals, with multiple correlation coefficients (R) around 0.8 and coefficient of determination (R2) around 0.6. The low standard deviation of error of prediction (SDEP < 0.1) and the high correlation coefficient of leave-one-out cross-validation (Q2) for all four biochemicals ranged from 0.56 to 0.61, which signifies the predictive ability of the models. The future projections show a considerable increase in the thresholds of all tested biochemicals. The distribution category with 'very high' concentrations of TPC and theanine is predicted to increase in the future by averages of 10% and 14%, respectively, while reducing the classes of protein and free sugar by 14% and 12%, respectively. Overall, the changing concentrations of the thresholds of relevant biochemicals and their distribution will negatively affect the final quality of tea, and these variations indicate that climate change has started to diminish Ceylon tea quality.

L-Theanine Alleviates IMQ-Induced Psoriasis Like Skin Inflammation by Downregulating the Production of IL-23 and Chemokines

Psoriasis, the most common skin inflammatory disease, is characterized by massive keratinocyte proliferation and immune cell infiltration into epidermis. L-Theanine (L-THE), a nonproteinogenic amino acid derived from green tea (Camellia sinensis), has been proved to possess the properties of anti-inflammatory, antidepressants and neuroprotective. However, whether L-THE has a therapeutic effect on psoriasis is still unknown. In this study, we found that the epidermal thickness and inflammatory response were significantly reduced in Imiquimod (IMQ)-induced psoriasis mice by applying with L-THE on mice skin. The expression of proliferation and inflammation associated genes such as keratin 17, IL-23 and CXCL1-3 was also downregulated by L-THE. Furthermore, L-THE inhibited the production of IL-23 in dendritic cells (DCs) after IMQ treatment, and decreased the levels of chemokines in keratinocytes treated with IL-17A by downregulating the expression of IL-17RA. RNA-seq and KEGG analysis revealed that L-THE significantly regulated the expression of IL-17A and NF-κB signaling pathway-associated genes. Metabolomics analysis displayed that L-THE promoted propanoate metabolism which has been reported to inhibit the activity of TH17 cells. Therefore, our results demonstrated that L-THE significantly decreases the levels of IL-23 and chemokines, and attenuates IMQ-induced psoriasis like skin inflammation by inhibiting the activation of NF-κB and IL-17A signaling pathways, and promoting the propanoate metabolism. Our findings suggest that topical applied L-THE can be used as a topical drug candidate for the treatment of psoriasis or as an adjuvant treatment of ustekinumab or secukinumab to prevent the relapse of psoriasis.

Green and white teas as health-promoting foods

Tea is one of the most consumed beverages around the world and as such, it is constantly the object of novel research. This review focuses on the research performed during the last five years to provide an updated view of the current position of tea regarding human health. According to most authors, tea health benefits can be traced back to its bioactive components, mostly phenolic compounds. Among them, catechins are the most abundant. Tea has an important antioxidant capacity and anti-inflammatory properties, which make this beverage (or its extracts) a potential aid in the fight against several chronic diseases. On the other hand, some studies report the possibility of toxic effects and it is advisable to reduce tea consumption, such as in the last trimester of pregnancy. Additionally, new technologies are increasing researchers' possibilities to study the effect of tea on human gut microbiota and even against SARS CoV-2. This beverage favours some beneficial gut microbes, which could have important repercussions due to the influence of gut microbiota on human health.

Natural antioxidants in the management of Parkinson's disease: Review of evidence from cell line and animal models

Parkinson's disease (PD) is a chronic progressive neurodegenerative disease. It results from the death of dopaminergic neurons. The pathophysiological mechanisms in idiopathic PD include the production of α-synuclein and mitochondrial respiratory function-affecting complex I, caused by reactive oxygen species. Therefore, the use of natural antioxidants in PD may provide an alternative therapy that prevents oxidative stress and reduces disease progression. In this review, the effects of hydroxytyrosol, Ginkgo biloba, Withania somnifera, curcumin, green tea, and Hypericum perforatum in PD animal and cell line models are compared and discussed. The reviewed antioxidants show evidence of protecting neural cells from oxidative stress in animal and cell models of PD. However, the clinical efficacy of these phytochemicals needs to be optimised and further investigated.

Semi-quantitative activity assays for high-throughput screening of higher activity gamma glutamyl transferase and enzyme immobilization to efficiently synthesize L-theanine

The bio-production of theanine is currently of significant interest due to its wide applications in food and healthcare products. Gamma glutamyl transferase (GGT) has been widely applied in L-theanine synthesis, but L-theanine yields remain prohibitively low for commercial production. In this study, a robust high-throughput screening process for isolating GGT mutants was developed through a combination of error-prone PCR techniques and a colorimetric reaction. The co-expression of PrsA lipoprotein enhances the secretion of GGT, thus GGT could be obtained quickly and easily without crushing cells. Random mutations on ggt genes were introduced by using error-prone PCR kits to build a large mutant library. A colorless compound generated by the reaction between NH⁴⁺ (released from L-theanine synthesis) and OPA was measured quantitatively by UV/visible spectroscopy when mixed with TCA and DMSO. Approximately 30 positive clones with improved color formation on the 96-well plates were identified, and mutants T413P and T463S with more than by 30 % higher transpeptidation activity versus the original GGT were isolated. To improve the operational stability and economical use, mutant GGT was immobilized on a prepared oxidized cellulose nanofiber membrane. The remaining activity of immobilized GGT was 88 % versus 72 % of free enzyme over 15 h. A fed-batch conversion was performed with the immobilized GGT, and over 70 g/L L-theanine could be accumulated within 18 h after feeding twice. Versus other studies, this is one of the best L-theanine synthesis systems using immobilized GGT.

Theanine Improves Salt Stress Tolerance via Modulating Redox Homeostasis in Tea Plants (Camellia sinensis L.)

Theanine, a unique non-proteinogenic amino acid, is one of the most abundant secondary metabolites in tea. Its content largely determines green tea quality and price. However, its physiological roles in tea plants remain largely unknown. Here, we showed that salt stress significantly increased the accumulation of glutamate, glutamine, alanine, proline, and γ-aminobutyric acid, as well as theanine, in the new shoots of tea plants. We further found that salt stress induced the expression of theanine biosynthetic genes, including CsGOGATs, CsAlaDC, and CsTSI, suggested that salt stress induced theanine biosynthesis. Importantly, applying theanine to the new shoots significantly enhanced the salt stress tolerance. Similar effects were also found in a model plant Arabidopsis. Notably, exogenous theanine application increased the antioxidant activity of the shoots under salt stress, suggested by reduced the reactive oxygen species accumulation and lipid peroxidation, as well as by the increased SOD, CAT, and APX activities and expression of the corresponding genes. Finally, genetic evidence supported that catalase-mediated antioxidant scavenging pathway is required for theanine-induced salt stress tolerance. Taken together, this study suggested that salt stress induces theanine biosynthesize in tea plants to enhance the salt stress tolerance through a CAT-dependent redox homeostasis pathway.

Functional Beverages, from Idea to Functionality

The search for, and development of beverages that could be a panacea is one which is several millennia old [...]

L-theanine: an astounding sui generis amino acid in poultry nutrition

L-theanine (γ-Glutamylethylamide) is a nonprotein water soluble amino acid (AA) mostly found in leaves of Camellia sinensis (green tea). This is a key component of green tea and is considered as the most abundant form of total AAs in green tea (i.e., about 50%). L-theanine is an exclusive taste ingredient of tea producing an attractive flavor and aroma in tea. It has biological effects such as antioxidant, growth promoter, immune booster, anti-stresser, hepatoprotective, antitumor, antiaging, antimicrobial, anti-inflammatory, and antianxiety activities that are worth noticing. It could reduce the oxidative impairment by reducing the synthesis of reactive oxygen species, oxidative parameters, and lipid damage as well as increasing the activity of antioxidant enzymes. The oral ingestion of L-theanine enhanced γδ T-cell proliferation. Therefore, it is being considered an essential compound of green tea that has the ability to improve immune function. The L-theanine can be used as a potential treatment for hepatic injury and immune-related liver diseases via the downregulation of the inflammatory response through the initiation of nitric oxide synthesis and glutathione production which are likely to be critical for the control of hepatic diseases as well as for the improvement of immune function. In addition, it could be used as a best natural feed additive with a potent antistressor by decreasing the levels of corticosterone, dopamine, and noradrenaline. After systematically reviewing the literature, it is noticed that most studies were carried out on mice, pig, human, and butterfly; while dietary supplementation studies of L-theanine in animal and poultry especially among broilers are very limited because of less awareness of this AA. So, the aim of this review is to encourage the veterinarian and poultry researchers to conduct more research at the molecular level about this AA to expose its more beneficial effects and its mechanism of absorption for potential use of this unique green tea AA in poultry nutrition.

Microbial Engineering for Production of N-Functionalized Amino Acids and Amines

N-functionalized amines play important roles in nature and occur, for example, in the antibiotic vancomycin, the immunosuppressant cyclosporine, the cytostatic actinomycin, the siderophore aerobactin, the cyanogenic glucoside linamarin, and the polyamine spermidine. In the pharmaceutical and fine-chemical industries N-functionalized amines are used as building blocks for the preparation of bioactive molecules. Processes based on fermentation and on enzyme catalysis have been developed to provide sustainable manufacturing routes to N-alkylated, N-hydroxylated, N-acylated, or other N-functionalized amines including polyamines. Metabolic engineering for provision of precursor metabolites is combined with heterologous N-functionalizing enzymes such as imine or ketimine reductases, opine or amino acid dehydrogenases, N-hydroxylases, N-acyltransferase, or polyamine synthetases. Recent progress and applications of fermentative processes using metabolically engineered bacteria and yeasts along with the employed enzymes are reviewed and the perspectives on developing new fermentative processes based on insight from enzyme catalysis are discussed.

The Effect of L-Theanine Incorporated in a Functional Food Product (Mango Sorbet) on Physiological Responses in Healthy Males: A Pilot Randomised Controlled Trial

Consumption of L-Theanine (L-THE) has been associated with a sensation of relaxation, as well as a reduction of stress. However, these physiological responses have yet to be elucidated in humans where L-THE is compared alongside food or as a functional ingredient within the food matrix. The aim of this study was to determine the physiological responses of a single intake of a potential functional food product (mango sorbet) containing L-THE (ms-L-THE; 200 mgw/w) in comparison to a flavour and colour-matched placebo (ms). Eighteen healthy male participants were recruited in this randomised, double-blind, placebo-controlled trial. The participants were required to consume ms-L-THE or placebo and their blood pressure (BP) (systolic and diastolic), heart rate (HR), and heart rate variability (HRV) were monitored continuously over 90 minutes. Eleven males (age 27.7 ± 10.8 years) completed the study. Changes in area under the curve for systolic and diastolic blood pressure and HRV over the 90 minute observation period indicated no differences between the three conditions (all p > 0.05) or within individual groups (all p > 0.05). The values for heart rate were also not different in the placebo group (p = 0.996) and treatment group (p = 0.066), while there was a difference seen at the baseline (p = 0.003). Based on the findings of this study, L-THE incorporated in a food matrix (mango sorbet) demonstrated no reduction in BP or HR and showed no significant parasympathetic interaction as determined by HRV high-frequency band and low-frequency/high-frequency ratio. Further studies should be focussed towards the comparison of pure L-THE and incorporation within the food matrix to warrant recommendations of L-THE alongside food consumption.

The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review

The green tea amino acid, L-theanine (L-THE) is associated with several health benefits, including improvements in mood, cognition and a reduction of stress and anxiety-like symptoms. This systematic review evaluated the effect of pure L-THE intake, in the form of orally administered nutritional supplements, on stress responses and anxiety levels in human randomised controlled trials. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, 9 peer-reviewed journal articles were identified where L-THE as a supplement was compared to a control. Our findings suggest that supplementation of 200-400 mg/day of L-THE may assist in the reduction of stress and anxiety in people exposed to stressful conditions. Despite this finding, longer-term and larger cohort clinical studies, including those where L-THE is incorporated into the diet regularly, are needed to clinically justify the use of L-THE as a therapeutic agent to reduce stress and anxiety in people exposed to stressful conditions.

Recent advances in microbial glutaminase production and applications-a concise review

This article focuses on significant advances in the production and applications of microbial glutaminases and provides insight into the structures of different glutaminases. Glutaminases catalyze the deamidation of glutamine to glutamic acid, and this unique ability forms the basis of their applications in various industries such as pharmaceutical and food organizations. Microbial glutaminases from bacteria, actinomycetes, yeast, and fungi are of greater significance than animal glutaminases because of their stability, affordability, and ease of production. Owing to these notable benefits, they are considered to possess considerable potential in anticancer and antiviral therapy, flavor enhancers in oriental foods, biosensors and in the production of a nutraceutical theanine. This review also aims to fully explore the potential of microbial glutaminases and to set the pace for future prospects.

A review of the alleged health hazards of monosodium glutamate

Monosodium glutamate (MSG) is an umami substance widely used as flavor enhancer. Although it is generally recognized as being safe by food safety regulatory agencies, several studies have questioned its long-term safety. The purpose of this review was to survey the available literature on preclinical studies and clinical trials regarding the alleged adverse effects of MSG. Here, we aim to provide a comprehensive overview of the reported possible risks that may potentially arise following chronic exposure. Furthermore, we intend to critically evaluate the relevance of this data for dietary human intake. Preclinical studies have associated MSG administration with cardiotoxicity, hepatotoxicity, neurotoxicity, low-grade inflammation, metabolic disarray and premalignant alterations, along with behavioral changes. Moreover, links between MSG consumption and tumorigenesis, increased oxidative stress and apoptosis in thymocytes, as well as genotoxic effects in lymphocytes have been reported. However, in reviewing the available literature, we detected several methodological flaws, which led us to conclude that these studies have limited relevance for extrapolation to dietary human intakes of MSG risk exposure. Clinical trials have focused mainly on the effects of MSG on food intake and energy expenditure. Besides its well-known impact on food palatability, MSG enhances salivary secretion and interferes with carbohydrate metabolism, while the impact on satiety and post-meal recovery of hunger varied in relation to meal composition. Reports on MSG hypersensitivity, also known as 'Chinese restaurant syndrome', or links of its use to increased pain sensitivity and atopic dermatitis were found to have little supporting evidence. Based on the available literature, we conclude that further clinical and epidemiological studies are needed, with an appropriate design, accounting for both added and naturally occurring dietary MSG. Critical analysis of existing literature, establishes that many of the reported negative health effects of MSG have little relevance for chronic human exposure and are poorly informative as they are based on excessive dosing that does not meet with levels normally consumed in food products.

The Association between Green and Black Tea Consumption on Successful Aging: A Combined Analysis of the ATTICA and MEDiterranean ISlands (MEDIS) Epidemiological Studies

Tea is one of the most-widely consumed beverages in the world with a number of different beneficial health effects, mainly ascribed to the polyphenolic content of the tea catechins. The aim of this study was to examine the consumption of green, black, or no tea, in relation to the previously validated successful ageing index (SAI; higher values "healthier" ageing) in a combined analysis of adults aged >50 years old from the ATTICA (n = 1128 adults from Athens, Greece metropolitan area) and the MEDiterranean Islands Study (MEDIS) (n = 2221 adults from various Greek island and Mani) studies. After adjusting for age, sex, smoking, and coffee consumption, green tea was positively associated with SAI (b ± SE: 0.225 ± 0.055, p < 0.001), while black tea was negatively associated with SAI (unstandardized b coefficient ± Standard error: -0.807 ± 0.054, p < 0.001). Green tea (vs black tea) consumption, had higher odds of a SAI of over 3.58 out of 10 (OR: 1.77, 95% CI: 1.38-2.28). Green tea consumption was also associated with higher levels of physical activity (p < 0.001) and reduced likelihood of hypertension (p = 0.006) compared with black tea. Two possible mechanisms are that green tea possesses high levels of catechins such as (-)-epigallocatechin 3-gallate and l-theanine compared with black tea. Therefore, the present analysis supports both the role of green tea constituents in successful ageing, as well as its role as an important component of an overall healthy diet in adults aged 50 years and over from these two epidemiological studies.

Using Caffeine and Free Amino Acids To Enhance the Transepithelial Transport of Catechins in Caco-2 Cells

Catechins are well-known to possess health-promoting functions. The interaction of the catechins with other components in tea could alter their absorption and efflux. This study investigated whether the absorption of catechins is affected by caffeine and amino acids using the Caco-2 monolayer cell model. We found that (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG), and (-)-epicatechin (EC) were all actively effluxed. Co-transportation of EGCG, ECG, or EC with caffeine, theanine, serine, or glycine increased their apparent permeability coefficient [ P_app(AP-BL)] value by 3.42-5.40- fold, 1.19-5.75-fold, and 1.55-8.01-fold, respectively. Meanwhile, their efflux ratio values were significantly decreased. Moreover, the expression of multi-drug resistance protein 2 (MRP2) after 3 h of incubation with either 50 μM EGCG or 50 μM EC was elevated by 1.58- and 2.98-fold, respectively, while 50 μM ECG had no significantly effects. In addition, the expression of P-glycoprotein (P-gp) after treatment with either 50 μM EGCG, 50 μM ECG, or 50 μM EC was enhanced by 1.53-, 1.63-, and 1.80-fold, respectively. The addition of either caffeine or any one of the three amino acids decreased the expression of both MRP2 and P-gp induced by EGCG, and the expression of P-gp induced by ECG or EC also decreased. In contrast, only glycine decreased the expression of MRP2 induced by EC. Taken together, our data indicated that caffeine and theanine, glycine, or serine in tea might increase the absorption of catechins by the selectively suppressed expression of the efflux transporters induced by catechins.

Comprehensive evaluation of the composition of Mingshan Laochuancha green tea and demonstration of hypolipidemic activity in a zebrafish obesity model

Laochuancha is an ancient tea plant originating from the Mingshan district of Ya'an city, Sichuan province, China, which is used to produce tea products with excellent quality. Mingshan Laochuancha green tea (MLGT) is a type of green tea manufactured from Laochuancha tea leaves. Currently, not much is known regarding the chemical compositions of MLGT and its bioactivity. Herein, the present study explores, for the first time, the chemical compositions and hypolipidemic activity of MLGT. It was observed that K was the most abundant element of 26.58 mg g⁻¹, and contents of toxic As, Cd, Cr and Pb elements were all below concentration limits. Alcohols (55.65%) were the main volatiles, and numerous volatiles with chestnut-like aroma were detected. Total content of 21 amino acids was 28.61 mg g⁻¹, and amino acids with velvety-like and umami taste totally accounted for 65.39%. The high content of amino acids and low ratio of polyphenols to total amino acids were attributed to strong umami and mellow taste of MLGT. Moreover, catechins and alkaloids were abundant in MLGT, where EGCG (85.82 mg g⁻¹) and caffeine (33.78 mg g⁻¹) were at highest content. Analyses of chemical compositions revealed excellent quality of MLGT. Correspondingly, MLGT showed potent hypolipidemic activity, and water extract of MLGT at 200 μg mL⁻¹ significantly reduced lipid level to 43.06% of high-fat zebrafish. Results firstly revealed the quality characteristics of MLGT and provided further insights into bioactivity of Laochuancha.

MLGT was investigated for the first time, and results revealed excellent quality and potent hypolipidemic activity of MLGT.