Untangling the impact of plantation type and functional traits on ecosystem nutrient stocks in an experimentally restored forest ecosystem.

The primary objective of ecological restoration is recovering biodiversity and ecosystem functioning. While a functional trait-based approach can help understand community assembly and ecosystem function recovery during ecological restoration, there still exists a knowledge gap in assessing how functional traits indicate the mediating roles of the plant community in response to forest restoration effects on ecosystem functions. This study applied the "response-effect trait" framework to investigate experimentally whether the treatment of plantation type has an impact on community trait compositions, which in turn could affect forest ecosystem nutrient stocks - here, carbon (C) and nitrogen (N) and phosphorus (P) stocks in tree, understory, litter and soil pools at an experimental station in subtropical China. We used structural equation models (SEMs) to examine the relationships among plantation type, community weighted mean of traits, and nutrient stocks in each pool. Our results show that most of the tree and understory traits studied were response traits to plantation type. Moreover, certain traits played a significant role in mediating plantation-type effects on C, N and P stocks for understory pool (e.g., understory stem specific density and specific leaf area, tree leaf phosphorus content), and for litter and soil pools (e.g., tree leaf carbon or phosphorus content, understory specific leaf area, leaf nitrogen or phosphorus content), known as "response-effect traits". For the tree pool, only effect traits, and no "response-effect" tree traits, were found for the N stock. Total effects of SEMs indicated that, understory or tree traits can have a greater impact than plantation type on understory or litter C, N or P stocks. After approximately 35 years of natural restoration, exotic plantations exhibited a different community trait characteristic from native plantations. The important roles of traits in mediating the effects of plantation type on non-tree pool C, N and P stocks were highlighted.

Disentangling drivers of litter decomposition in a multi-continent network of tree diversity experiments.

Litter decomposition is a key ecosystem function in forests and varies in response to a range of climatic, edaphic, and local stand characteristics. Disentangling the relative contribution of these factors is challenging, especially along large environmental gradients. In particular, knowledge of the effect of management options, such as tree planting density and species composition, on litter decomposition would be highly valuable in forestry. In this study, we made use of 15 tree diversity experiments spread over eight countries and three continents within the global TreeDivNet network. We evaluated the effects of overstory composition (tree identity, species/mixture composition and species richness), plantation conditions (density and age), and climate (temperature and precipitation) on mass loss (after 3 months and 1 year) of two standardized litters: high-quality green tea and low-quality rooibos tea. Across continents, we found that early-stage decomposition of the low-quality rooibos tea was influenced locally by overstory tree identity. Mass loss of rooibos litter was higher under young gymnosperm overstories compared to angiosperm overstories, but this trend reversed with age of the experiment. Tree species richness did not influence decomposition and explained almost no variation in our multi-continent dataset. Hence, in the young plantations of our study, overstory composition effects on decomposition were mainly driven by tree species identity on decomposer communities and forest microclimates. After 12 months of incubation, mass loss of the high-quality green tea litter was mainly influenced by temperature whereas the low-quality rooibos tea litter decomposition showed stronger relationships with overstory composition and stand age. Our findings highlight that decomposition dynamics are not only affected by climate but also by management options, via litter quality of the identity of planted trees but also by overstory composition and structure.

Estimation of air pollution tolerance and anticipated performance index of roadside plants along the national highway in a tropical urban city.

One of the most serious environmental issues is air pollution. Unlike other environmental concerns, this form of pollution is extremely challenging to regulate. The greenery of roadside trees plays a significant role in air purification and pollutant absorption, therefore helping to mitigate environmental pollution. Several plants can absorb and store toxins in their leaves from the atmosphere. Green plants have the potential to work as sinks and filters for air pollutants. Green belt development along national highways is a cost-effective and environmentally sustainable method of reducing air pollution. Sensitive and tolerant plants against air pollution can be identified by evaluating their air pollution tolerance index (APTI) and anticipated performance index (API) values. In this study, the susceptibility level of plant species to air pollution was assessed using APTI and API. The four parameters on which APTI depends are ascorbic acid content, total chlorophyll content, relative water content, and leaf extract pH. For the estimation of API, the plant's biological and socioeconomic factors like tree habit, canopy structure, type, size, texture, and hardness of the plant are also assessed. These parameters were determined and incorporated into a formula that represents the APTI and API of plants. Moreover, multilinear regression modeling was performed using a Statistical Package for the Social Sciences (SPSS, V25) and found that pH and ascorbic acid content in plant leaves have a significant role in the calculation of APTI and tolerance potential of plants. Therefore, APTI was assessed with seventeen plant species that are abundant in the area along the national highway in Kanpur, Uttar Pradesh, from Jan to Mar 2020. The APTI showed that Saraca asoca was the most resistant to air pollution, whereas Vachellia nilotica was the most sensitive. In addition, plants with higher APTI can also be used to reduce air pollution, while plants with lower APTI can be utilized to monitor air pollution. Based on the calculated API score, it is found that Ficus elastica (% score > 90) is the best option for green belt development. Urban local body (ULB) can also adopt Ficus religiosa, Saraca asoca, and Aucuba japonica (having % a grade score of 80-90) for mitigation of air pollution. The study indicates that plantations of tolerant species are useful for biomonitoring and developing green belts on and along national highways.

Response of soil and vegetation in a warm-temperate Pine forest to intensive biomass harvests, phosphorus fertilisation, and wood ash application.

The objective of this study was to assess the effects of different intensities of biomass harvesting, and the possible effects of compensation methods, on forest functioning. To do so, we carried out a split-plot experiment (SW France) crossing four different intensities of biomass harvesting (Stem-Only Harvest [SOH], Aboveground Additional Harvest [AAH], Belowground Additional Harvest [BAH], and Whole-Tree Harvest [WTH]) and three compensation methods (control [C], wood ash application [A] and phosphorus fertilisation [P]). The experimental treatments were followed by the plantation of pines (Pinus pinaster). The environmental consequences of treatments on soil and vegetation were evaluated 11 years after the tree plantation. Despite their low additional biomass exports (+10 % for AAH to +34 % for WTH), the non-conventional harvest practices exported much higher quantities of nutrients than the conventional SOH technique (+145 % of exported N in WTH). Additional biomass harvests impacted the soil organic matter content, with negative effects on P-organic, soil cation exchange capacity, exchangeable Ca, and most extractible nutrients. However, tree nutritional status was improved by P-fertiliser or wood ash. We observed a positive effect of wood ash application on soil pH and nutrient content but, like additional harvests, wood ash application decreased the pool of soil organic carbon (~10 %). Overall, the experiment showed that exporting more forest biomass due to the additional harvesting of biomass had negative consequences on the ecosystem biogeochemistry. Additional harvests have impoverished the soil, and decreased the soil organic carbon content. Importantly, applying nutrients as fertiliser or wood ash did not compensate for all the negative impacts of biomass exports and the method of wood ash recycling in forests could even decrease the soil organic carbon.

Cytotoxic activity of strawberry tree (Arbutus unedo L.) honey, its extract, and homogentisic acid on CAL 27, HepG2, and Caco-2 cell lines.

Strawberry tree (Arbutus unedo L.) honey (STH), also known as "bitter honey", is a traditional medicine widely used in the Mediterranean area. Regardless of geographical origin, it usually has a very high content of phenolic compounds and strong antioxidant capacity. Yet, little is still known about the effects of STH, its phenolic extract (STHE), and its main bioactive compound - homogentisic acid (HGA) - at the cell level. The aim of this study was to estimate total phenolic content, DPPH radical scavenging activity, and ferric reducing antioxidant power of STH made in Croatia and investigate cytotoxic and pro-oxidative effects of STH, STHE and HGA on three human cell lines: tongue squamous cell carcinoma (CAL 27), hepatocellular carcinoma (HepG2), and epithelial colorectal adenocarcinoma cells (Caco-2) cells. These substances were tested at four concentrations (0.5-5× average human daily intake of STH) and over 30 min and 1 and 2 h. Croatian STH had a total phenolic content of 1.67 g gallic acid equivalents (GAE) per kg of honey, DPPH radical scavenging activity of 2.96 mmol Trolox equivalents (TE) per kg of honey, and ferric reducing antioxidant power (FRAP) of 13.5 mmol Fe2+ per kg of honey. Our results show no clear and consistent time- or concentration-dependent cytotoxicity in any of the cell lines. ROS levels in all the three cell types at almost all exposure times were not significantly higher than control. The most important observation is that the tested substances have low cytotoxicity and high biocompatibility, regardless of concentration, which is a good starting point for further research of their biological effects in other models.

Isolation and Characterization of Two Chalcone Derivatives with Anti-Hepatitis B Virus Activity from the Endemic Socotraen Dracaena cinnabari (Dragon's Blood Tree).

Hepatitis B virus (HBV) infection is prevalent and continues to be a global health concern. In this study, we determined the anti-hepatitis B virus (HBV) potential of the Socotra-endemic medicinal plant Dracaena cinnabari and isolated and characterized the responsible constituents. A bioassay-guided fractionation using different chromatographic techniques of the methanolic extract of D. cinnabari led to the isolation of two chalcone derivatives. Using a variety of spectroscopic techniques, including 1H-, 13C-, and 2D-NMR, these derivatives were identified as 2,4'-dihydroxy-4-methoxydihydrochalcone (compound 1) and 2,4'-dihydroxy-4-methoxyhydrochalcone (compound 2). Both compounds were isolated for the first time from the red resin (dragon's blood) of D. cinnabari. The compounds were first evaluated for cytotoxicity on HepG2.2.15 cells and 50% cytotoxicity concentration (CC50) values were determined. They were then evaluated for anti-HBV activity against HepG2.2.15 cells by assessing the suppression of HBsAg and HBeAg production in the culture supernatants and their half maximum inhibitory concentration (IC50) and therapeutic index (TI) values were determined. Compounds 1 and 2 indicated inhibition of HBsAg production in a dose- and time-dependent manner with IC50 values of 20.56 and 6.36 µg/mL, respectively.

Phytochemical Screening and Antioxidant Activity of Seven Native Species Growing in the Forests of Southern Chilean Patagonia.

The genus Nothofagus is one of the most abundant in the subantarctic Patagonian forests. Five species inhabit these ecosystems, three evergreen (Nothofagus betuloides, Nothofagus dombeyi, and Nothofagus nitida) and two deciduous (Nothofagus pumilio and Nothofagus antarctica). This is the first report on the levels of secondary metabolites and the antioxidant capacity of Patagonian tree species growing in natural environments. The aim of this work was to carry out a phytochemical screening, to determine the antioxidant capacity, the sun protection factor, and the α-glucosidase and tyrosinase inhibitory activity of foliar extracts of the five previous species. Besides, Aristotelia chilensis and Berberis microphylla, two species of Patagonian shrubs growing in the same forests, were used as reference. N. dombeyi was the Nothofagus with the best antioxidant capacity. B. microphylla differed from all studied species. Moreover, the Nothofagus was split into two groups. N. betuloides and N. dombeyi are the most similar species to A. chilensis. The α-glucosidase was completely inhibited by all studied extracts. Furthermore, N. antarctica, N.pumilio, and N. nitida inhibited about 70% of the tyrosinase activity. All the results found in this study for the species of the genus Nothofagus support further research on their potential beneficial properties for human health.

The Chemical Composition of Oils and Cakes of Ochna serrulata (Ochnaceae) and Other Underutilized Traditional Oil Trees from Western Zambia.

Currently, the negative effects of unified and intensive agriculture are of growing concern. To mitigate them, the possibilities of using local but nowadays underused crop for food production should be more thoroughly investigated and promoted. The soybean is the major crop cultivated for vegetable oil production in Zambia, while the oil production from local oil-bearing plants is neglected. The chemical composition of oils and cakes of a three traditional oil plant used by descendants of the Lozi people for cooking were investigated. Parinari curatellifolia and Schinziophyton rautanenii oils were chiefly composed of α-eleostearic (28.58-55.96%), linoleic (9.78-40.18%), and oleic acid (15.26-24.07%), whereas Ochna serrulata contained mainly palmitic (35.62-37.31%), oleic (37.31-46.80%), and linoleic acid (10.61-18.66%); the oil yield was high (39-71%). S. rautanenii and O. serrulata oils were rich in γ-tocopherol (3236.18 µg/g, 361.11 µg/g, respectively). The O. serrulata oil also had a very distinctive aroma predominantly composed of p-cymene (52.26%), m-xylene (9.63%), γ-terpinene (9.07%), o-xylene (7.97), and limonene (7.23%). The cakes remaining after oil extraction are a good source of essential minerals, being rich in N, P, S, K, Ca, and Mg. These plants have the potential to be introduced for use in the food, technical, or pharmaceutical industries.

Impact of Harvest Conditions and Host Tree Species on Chemical Composition and Antioxidant Activity of Extracts from Viscum album L.

The content of plant secondary metabolites is not stable, and factors such as the region/location effect and seasonal variations have an impact on their chemical composition, especially in parasitic plants. Research in this area is an important step in the development of quality parameter standards of medicinal plants and their finished products. The effects of the time and place of harvest and the host tree species on the chemical composition and antioxidant activity of mistletoe extracts were investigated. Statistical tools were used to evaluate the results of the spectrophotometric and LC-ESI-MS/MS studies of the phenolic composition and antioxidant activity. The investigations indicate that the qualitative and quantitative composition, influencing the biological activity of mistletoe extracts, largely depends on the origin of the plant. The mistletoe extracts exhibited a rich phenol profile and high antioxidant activity. The chemometric analysis indicated that mistletoe collected from conifers (Viscum abietis and Viscum austriacum) had the most advantageous chemical composition and antioxidant activity. Moreover, the chemical profile and biological activity of the plant material were closely related to the climatic conditions and location of the harvested plant. Higher levels of phenolic compounds and high antioxidant activity were found in extracts obtained from plant material collected in cold weather with the presence of snow and less sunshine (autumn-winter period).

Ethnopharmacology, biological activities and chemical compounds of Canarium strictum: An important resin-yielding medicinal tree in India.

The resin of Canarium strictum Roxb. is used for rheumatism and asthma; the bark is used as a mosquito repellent. The major compounds in the resin are triterpenoids, but as no studies have been performed on the bark, this study investigated this economically important resource. Ten folk healers were interviewed about their medicinal uses of C. strictum. Resin and bark were extracted with dichloromethane followed by methanol using accelerated solvent extraction. The extracts were fractionated using different chromatographic methods, and isolated compounds were identified by NMR spectroscopy and GC-MS. Resin and bark extracts were investigated for DPPH radical scavenging, 15-lipoxygenase inhibition, effects on nitric oxide (NO) production in LPS-activated dendritic D2SC/I cells and toxicity against Artemia salina nauplii. Traditional healers used resin to treat colds, airway afflictions and rheumatoid arthritis. α-Amyrin and ß-amyrin were identified as the major constituents in the dichloromethane resin extract. From the stem bark, procyanidins, gallic acid, methyl gallate, scopoletin, 3,3'-di-O-methylellagic acid 4-O-α-arabinofuranoside and elephantorrhizol (3,3',4',5,6,7,8-heptahydroxyflavan) were isolated and identified. By GC-MS, α-amyrin and ß-amyrin and their acetates, lupeol, and taraxasterol were identified. Radical scavenging, 15-lipoxygenase inhibitory activity and inhibition of NO production was observed from resin and bark extracts, and no toxicity towards Artemia salina nauplii was found. Triterpenoids and procyanidins are the major compounds in C. strictum resin and stem bark, respectively. The high content of triterpenoids might contribute to anti-inflammatory effects and give a rationale for the widespread usage of the resin in India.

Supercritical-CO2 extraction, identification and quantification of polyprenol as a bioactive ingredient from Irish trees species.

This study ascertained the accumulation of polyprenol from four Irish conifer species Picea sitchensis, Cedrus atlantica 'Glauca', Pinus sylvestris and Taxus baccata and one flowering tree Cotoneaster hybrida using supercritical fluid extraction with carbon dioxide (SFE-CO2) and solvent extraction. The effects of SFE-CO2 parameters such as temperature (ranged from 40 to 70 [Formula: see text]), pressure (ranged from 100 to 350 bars) and dynamic time (from 70 min to 7 h) were analysed on the extraction efficiency of polyprenol. Qualitative and quantitative analysis of polyprenol was examined using high-performance liquid chromatography. Results showed that P. sylvestris accumulated the highest polyprenol yield of 14.00  ± [Formula: see text]mg g-1 DW when extracted with hexane:acetone (1:1 v/v). However, with SFE-CO2 conditions of 200 bars, 70 [Formula: see text], 7 h, with absolute ethanol as a cosolvent with a flow rate of 0.05 ml min-1, P. sitchensis accumulated the highest polyprenol yield of 6.35 ± [Formula: see text] mg g-1DW. This study emphasised the potential application of SFE-CO2 in the extraction of polyprenol as an environmentally friendly method to be used in pharmaceutical and food industries.

Fruit tree leaves as unconventional and valuable source of chlorophyll and carotenoid compounds determined by liquid chromatography-photodiode-quadrupole/time of flight-electrospray ionization-mass spectrometry (LC-PDA-qTof-ESI-MS).

This study focused on the identification (by LC-PDA-qTof-ESI-MS) and quantification (by UPLC-PDA) of isoprenoids of the fruit tree leaves (FTL) of commonly consumed fruits: apple, pears, quince, apricot, peach, plums, sweet and sour cherry. The FTL were collected at 2 time points: after tree blooming and after fruit collection. In FTL 7 carotenoids and 16 chlorophylls were identified, but the number of labeled chlorophyll compounds depended on the species. FTL of apple, sour cherry and apricot were identified as the best sources of chlorophylls (mean 404.8, 388.7 and 364.5 mg/100 g dw, respectively) and sweet and sour cherry leaves as the best sources of carotenoids (831.4 and 1162.0 mg/100 g dw, respectively). A lower content of chlorophylls and carotenoids, but not significantly, was detected in leaves after autumn collection of fruits compared to leaves collected after blooming. Fruit tree leaves are good material for isolation of chlorophylls and carotenoids for application in cosmetics, pharmaceuticals or in the food industry, e.g. production of beverages or puree.

Dynamics of nitrogen and phosphorus accumulation and their stoichiometry along a chronosequence of forest primary succession in the Hailuogou Glacier retreat area, eastern Tibetan Plateau.

As the two limiting nutrients for plants in most terrestrial ecosystems, nitrogen (N) and phosphorus (P) are essential for the development of succession forests. Vegetation N:P stoichiometry is a useful tool for detecting nutrient limitation. In the present work, chronosequence analysis was employed to research N and P accumulation dynamics and their stoichiometry during forest primary succession in a glacier retreat area on the Tibetan Plateau. Our results showed that: (1) total ecosystem N and P pools increased from 97 kg hm-2 to 7186 kg hm-2 and 25 kg hm-2 to 487 kg hm-2, respectively, with increasing glacier retreat year; (2) the proportion of the organic soil N pool to total ecosystem N sharply increased with increasing glacier retreat year, but the proportion of the organic soil and the vegetation P pools to the total ecosystem P was equivalent after 125 y of recession; (3) the N:P ratio for tree leaves ranged from 10.1 to 14.3, whereas the N:P ratio for total vegetation decreased form 13.3 to 8.4 and remained constant after 35 y of recession, and the N:P ratio for organic soil increased from 0.2 to 23.1 with increasing glacier retreat. These results suggested that organic soil N increased with increasing years of glacier retreat, which may be the main sink for atmospheric N, whereas increased P accumulation in vegetation after 125 y of recession suggested that much of the soil P was transformed into the biomass P pool. As the N:P ratio for vegetation maintained a low level for 35-125 y of recession, we suggested that N might be the main limiting element for plant growth in the development of this ecosystem.

Biotic and abiotic factors causing the collapse of Robinia pseudoacacia L. veteran trees in urban environments.

Robinia pseudoacacia L. is an interesting example of how one plant species can be considered invasive or useful depending on its environment. In the past this tree species was planted for decorative purposes and for wood in Poland. For many years it was recommended in poor and degraded habitats because it facilitated late-successional plant species. The aim of this study was to verify if black locust can still be regarded as a resistant tree species in urban greenery. The health condition of old tree specimens growing along streets and in parks was compared. The occurrence of pests and pathogens on R. pseudoacacia trees was assessed and the content of mineral elements in leaves was examined. The research results showed that the health of black locust trees growing in the urban environment in Polish cities, especially along streets (in comparison to park sites), deteriorated significantly due to the interaction of harmful biotic and abiotic factors. Increased level of toxic metals (Fe, Zn, Pb, Mn and Cd) in plant tissues and the accumulation of pests and pathogens negatively influenced the health of R. pseudoacacia.

Gmelina arborea- an indigenous timber species of India with high medicinal value: A review on its pharmacology, pharmacognosy and phytochemistry.

ETHNOPHARMACOLOGICAL SIGNIFICANCE: Gmelina arborea Roxb.ex Smith, a fast-growing deciduous tree belongs to the family Lamiaceae, and is an important plantation species in many tropical areas around the world. The species is naturally distributed in semi-deciduous forests in tropical/subtropical regions of South East Asia. The tree is also an important medicinal plant in the Indian Systems of Medicine. The whole plant is used in medicine. It is astringent, bitter, digestive, cardiotonic, diuretic, laxative and pulmonary and nervine tonic. It improves digestion, memory, helps overcome giddiness and is useful in burning sensation, fever, thirst, emaciation, heart diseases, nervous disorders and piles. The roots are acrid, bitter-sweet in taste, stomachic, tonic, laxative, galactagogue and antihelmintic. The flowers are sweet, refrigerant, bitter, astringent and acrid, and are used in treating leprosy and skin diseases. The fruits are acrid, sour, sweet, refrigerant, bitter, astringent, aphrodisiac, trichogenous, alterant and tonic. Fruits are edible and also used for promoting hair growth and in treating anaemia, leprosy, ulcers, constipation, leucorrhoea and colitis. The leaves are a good fodder also. The major bioactive compounds extracted from different parts of G. arborea are arboreal, verbascoside, tyrosol, iridoids, phenylpropanoid glycoside, premnazole, martynoside, iridoid glycosides, balanophonin, gmelinol, isoarboreol apigenin, umbelliferone etc. AIM OF THE REVIEW: This review provides an insight into the medicinal aspects of G. arborea. It provides the latest information on phytochemistry, pharmacological activities and traditional uses of G.arborea. MATERIALS AND METHODS: Information on G. arborea was gathered from various sources like textbooks, literature, databases such as PubMed, Science Direct, Wiley, Springer, Taylor and Francis, Scopus, Inflibnet, Sci-Finder and Google Scholar. RESULTS: Sixty-nine phytochemicals which include lignans, acylated iridoid glycosides, acylated rhamnopyranoses, flavonoids, flavones, flavone glycosides have been isolated. Many of them have been characterized for their pharmacological activity. Several researchers have identified bioactive phytochemicals like luteolin, iridoid alkaloids from the leaves, hentriacontanol and lignans such as arboreol, isoarboreol, arborone, gmelanone, gummadiol from the heartwood, flavon glycosides in roots. The extracts are reported to have wound-healing and antidiarrheal properties. Various studies demonstrated that G.arborea and its constituents possess several pharmacological activities like anti-oxidant, anti-diabetic, anti-inflammatory, antiulcer, analgesic, anti-nociceptive, anticancer and wound healing activities. CONCLUSION: G. arborea is a valuable medicinal plant used traditionally in the Indian Systems of Medicine (ISM - Ayurveda and Unani) to treat a wide variety of ailments. These phytochemicals are highly bioactive and exhibit various pharmacological activities. However, pharmacological activities of many compounds which have been identified, are yet to be understood.

Major Fatty Acid Profiles and Bioactivity of Seed Oils from Ten†Tree Peony Cultivars as a Potential Raw Material Source for the Cosmetics and Healthy Products.

As a new woody oleaginous crop, tree peony is now being widely developed and utilized, which attributed to the outstanding oil-use features regarding the fatty acid profiles and bioactivity. The major fatty acid profiles and bioactivity of seed oils in ten tree peony varieties collected from a common garden were investigated in the present study. The results showed that the oil yields, fatty acid profiles, bioactivity of seed oils existed significant variations among ten tree peony varieties (P<0.05). Considered the application value, 'Fengdan' (FD) and 'Ziban' (ZB) was the optimal resources as the high oil yields, rich unsaturated fatty acids especially high α-linolenic acid of 40.46 %, great antioxidant activity with low IC50 values, high ABTS and FRAP values, and strong antimicrobial activity with high DIZ and low MIC/MBC values. The study also confirmed seed oil of tree peony as the potential raw materials sources in functional food, pharmaceuticals and cosmetics for human health.

Therapeutic Potential of Volatile Terpenes and Terpenoids from Forests for Inflammatory Diseases.

Forest trees are a major source of biogenic volatile organic compounds (BVOCs). Terpenes and terpenoids are known as the main BVOCs of forest aerosols. These compounds have been shown to display a broad range of biological activities in various human disease models, thus implying that forest aerosols containing these compounds may be related to beneficial effects of forest bathing. In this review, we surveyed studies analyzing BVOCs and selected the most abundant 23 terpenes and terpenoids emitted in forested areas of the Northern Hemisphere, which were reported to display anti-inflammatory activities. We categorized anti-inflammatory processes related to the functions of these compounds into six groups and summarized their molecular mechanisms of action. Finally, among the major 23 compounds, we examined the therapeutic potentials of 12 compounds known to be effective against respiratory inflammation, atopic dermatitis, arthritis, and neuroinflammation among various inflammatory diseases. In conclusion, the updated studies support the beneficial effects of forest aerosols and propose their potential use as chemopreventive and therapeutic agents for treating various inflammatory diseases.

α-Glucosidase inhibitory and nitric oxide production inhibitory activities of alkaloids isolated from a twig extract of Polyalthia cinnamomea.

The first phytochemical investigation of Polyalthia cinnamomea led to the isolation and identification of two new oxoprotoberberine alkaloids, (-)-(13aS)-polyalthiacinnamines A and B, together with eleven known compounds. The structures of the new compounds were elucidated by extensive spectroscopic methods. The absolute configuration of miliusacunine E and consanguine B was established by X-ray diffraction analysis using Cu Kα radiation and ECD spectra, whereas the absolute configurations of polyalthiacinnamines A and B were established by comparison of their ECD spectra and specific rotations with those of miliusacunine E and consanguine B. Compounds 1-4, 6, and 8 exhibited α-glucosidase inhibitory activities (IC50 values ranging from 11.3 to 57.9 µM) better than a positive control (acarbose, IC50 83.5 µM). Compound 2 also exhibited NO production inhibitory activity with an IC50 value of 24.4 µM (indomethacin, a positive control, IC50 = 32.2 µM).

Antioxidant evaluation-guided chemical profiling and structure-activity analysis of leaf extracts from five trees in Broussonetia and Morus (Moraceae).

Morus and Broussonetia trees are widely used as food and/or feed. Among 23 phenolics identified from leaves of five Moraceae species using UPLC-QTOF-MS/MS, 15 were screened using DPPH/ABTS-guided HPLCs, including seven weak (flavonoids with one hydroxyl on B-ring) and eight strong (four caffeoylquinic acids and four flavonoids, each with a double hydroxyl on B-ring) antioxidants. We then determined the activity and synergistic effects of individual antioxidants and a mixture of the eight strongest antioxidants using DPPH-guided HPLC. Our findings revealed that (1) flavonoid glucuronide may have a more negative effect on antioxidant activity than glucoside, and (2) other compounds in the mixture may exert a negative synergistic effect on antioxidant activity of the four flavonoids with B-ring double hydroxyls but not the four caffeoylquinic acids. In conclusion, the eight phenolics with the strongest antioxidant ability reliably represented the bioactivity of the five extracts examined in this study. Moreover, the Morus alba hybrid had more phenolic biosynthesis machinery than its cross-parent M. alba, whereas the Broussonetia papyrifera hybrid had significantly less phenolic machinery than B. papyrifera. This difference is probably the main reason for livestock preference for the hybrid of B. papyrifera over B. papyrifera in feed.

Increasing atmospheric CO2 concentrations correlate with declining nutritional status of European forests.

The drivers of global change, including increases in atmospheric CO2 concentrations, N and S deposition, and climate change, likely affect the nutritional status of forests. Here we show forest foliar concentrations of N, P, K, S and Mg decreased significantly in Europe by 5%, 11%, 8%, 6% and 7%, respectively during the last three decades. The decrease in nutritional status was especially large in Mediterranean and temperate forests. Increasing atmospheric CO2 concentration was well correlated with the decreases in N, P, K, Mg, S concentrations and the increase of N:P ratio. Regional analyses indicated that increases in some foliar nutrient concentrations such as N, S and Ca in northern Europe occurred associated with increasingly favourable conditions of mean annual precipitation and temperature. Crucial changes in forest health, structure, functioning and services, including negative feedbacks on C capture can be expected if these trends are not reversed.