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One cause of diarrhea is a bacterial infection. Tea (Camellia sinensis) is a steeping drink that has the efficacy of treating diarrhea. This looks at goals to decide the effect of formulations of three tea extracts that act as antibacterial causes of diarrhea and decide the most appropriate maceration temperature. Extraction was carried out with water solvents at temperatures 70oC, 100oC, and 121oC. The disc method conducted an antibacterial test against E. coli and S. aureus. The most optimal temperature for producing the highest inhibitory zone is the temperature of 100oC. Tea extract temperatures of 100oC are used for antibacterial testing. BSLT test showed the LC50 value of 1800 µg/mL. Tests on E. coli bacteria showed the highest results in a single white tea extract with a diameter of 9.750 mm, and tests on S. aureus showed the highest results in the three tea extract formula with a diameter of 9.65 mm. The inhibitory area evaluation of the system changed into finished using the simplex-centroid design method. It showed a non-huge linear model in the antibacterial test in opposition to E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

The New Zealand Emissions Trading Scheme allows landowners to be remunerated for the carbon sequestration capabilities of eligible forests established post 1990. For afforested areas of 100 hectares or fewer, carbon sequestration is estimated with the use of default carbon look-up tables administered by the Ministry for Primary Industries. However, a disparity exists between exotic pines (Pinus radiata), where carbon sequestration predictions are regionally differentiated, and native species, where carbon sequestration estimations are neither distinguished by species or locality. This paper aims to highlight this inequality by comparing the calculated carbon storage of endemic tree species with the 'Indigenous Forest' category in the carbon look-up tables. The carbon storage of 12-year-old naturally regenerated tea trees (Leptospermum scoparium and Kunzea ericoides) was calculated using allometric measurements and compared to the look-up tables. The results suggest that carbon look-up tables underestimate the carbon sequestration of native tea trees by 81.8%. A bimodal data distribution suggests that carbon sequestration is heavily dependent on light interception levels. It is recommended that carbon sequestration data for specific native species in different environments are collected and integrated into such tables. [ABSTRACT FROM AUTHOR]

The potential of ultra-violet (UV) light to replace the traditional brewing process to make cold tea in terms of inactivation of endogenous microflora has not been explored. Thus, the efficacy of emerging technologies such as UV-C by tea leaves/water ranging from 1 to 3 %, number of lamps ranging from 2 to 8, and number of cycles ranging from 4 to 8 were performed to determine the inactivation of total mesophilic aerobic bacteria (TMAB) and total mold and yeast (TMY) and changes in quality properties in cold drip white tea. The UV-light process was effective to reduce both TMAB and TMY. Increased number of cycles provided a significant amount of inactivation on both TMAB and TMY. The reduction of initial number of TMY was determined as 3.40±0.03 log cfu/mL with the number of lamps of 5, the number of cycle of 4, and tea leaves/water ratio of 1%, whereas TMAB were found as 3.12±0.08 log cfu/with the number of lamps of 2, the number of cycles of 6 and tea leaves/water ratio of 1%. The resulting datasets were used to predict the inactivation of TMAB and TMY in cold drip white tea using gradient boosting regression tree (GBRT), random forest regression (RFR), and artificial neuron network (ANN) models. The ANN model provided the lowest RMSE and highest R2 value for predicted inactivation of TMAB. TMY has not been predicted using either machine or neural networks. UV treatment possess a viable alternative for microbial inactivation without adverse effect on the quality properties of cold drip white tea. [ABSTRACT FROM AUTHOR]

Kanuka oil (Kunzea ericoides) is an endemic tree throughout New Zealand. A volatile oil is commercially produced from the leaves and branches by steam or vacuum distillation in various geographical locations around New Zealand Islands. Whilst the tree is closely related to Manuka (Leptospermum scoparium), chemically it is quite diverse. In commercially available oil, little attention is paid to understanding where the oil has come from geographically or the chemical diversity. This presentation will highlight the range of differences in the chemistry of commercially available oils from different locations, where the key constituents, α-pinene and linalool, vary significantly. In addition, minor constituents are also present or absent in different locations (Maddocks, 2021). Following this a series of studies were undertaken on two common pathogenic fungi, T. rubric and M. canis. These are implicated in a number of minor skin conditions. The in vitro studies found that Kanuka oil from Great Barrier Island in the north was the most effective against both organisms, despite a lower α-pinene content. Alpha-pinene in isolation has been found to be effective in treating M. canis (Silva et al., 2017). The age of the branches also were important. These effects were dose dependent. The oil with the highest &#*945;-pinene had the lowest antifungal effect. This work suggests that there are key actions of the minor constituents which contribute to the overall effect, rather than just one or two major constituents. Kanuka oil is considered a safe and non irritating oil for skin use and a further study is underway to test for allergic reactions in the various percentages. [ABSTRACT FROM AUTHOR]

The New Zealand Emissions Trading Scheme allows landowners to be remunerated for the carbon sequestration capabilities of eligible forests established post 1990. For afforested areas of 100 hectares or fewer, carbon sequestration is estimated with the use of default carbon look-up tables administered by the Ministry for Primary Industries. However, a disparity exists between exotic pines (Pinus radiata), where carbon sequestration predictions are regionally differentiated, and native species, where carbon sequestration estimations are neither distinguished by species or locality. This paper aims to highlight this inequality by comparing the calculated carbon storage of endemic tree species with the ‘Indigenous Forest’ category in the carbon look-up tables. The carbon storage of 12-year-old naturally regenerated tea trees (Leptospermum scoparium and Kunzea ericoides) was calculated using allometric measurements and compared to the look-up tables. The results suggest that carbon look-up tables underestimate the carbon sequestration of native tea trees by 81.8%. A bimodal data distribution suggests that carbon sequestration is heavily dependent on light interception levels. It is recommended that carbon sequestration data for specific native species in different environments are collected and integrated into such tables.

White tea has been of increasing public interest worldwide owing to its health benefits. Based on 2 years of surveillance, the long‐term and cumulative chronic exposure risks of pesticide residues through white tea drinking were assessed for different subpopulations in Fujian, China. Twenty‐five different pesticides were found, and 74.8% of samples contained at least one pesticide residue. The most frequently detected pesticide was bifenthrin with detection rates of 61.6%. Risk assessment was performed using both the deterministic approach and semiprobabilistic model under the best‐case and the worst‐case scenarios. The results demonstrated that the dietary risks were extremely low for six different subpopulations in which the risks for adults over the age of 41 were relatively higher. The risk ranking scheme indicated that isocarbophos and triazophos were considered to be of medium risk. The different use suggestions for the 25 positive pesticides are proposed to further minimize the exposure risk to consumer health. Practical Application: Tea is the second most popular nonalcoholic beverage throughout the world. Pesticides are used to improve the yield of tea. Pesticide residues in tea could be one of the exposure pathways for consumers. Monitoring residual levels and assessing the health risk assessment in tea are thus in an urge. [ABSTRACT FROM AUTHOR]

Alzheimerʼs disease (AD) is a neurodegenerative disease leading to irreversible neuronal damage. Kanuka or Kunzea ericoides (A. Richard) revealed a remarkable inhibition of β-secretase activity, an important enzyme for AD. This study presents optimization of the ultrasound assisted extraction (UAE) of inhibitors of β-secretase and antioxidants from K. ericoides leaves, and yield by response surface methodology (RSM). Experimental validation of optimized conditions and 50% inhibitory extract concentrations (IC50) determinations were performed. The extraction time and temperature were significant for enzyme inhibition, RSA (DPPH radical scavenging activity) and yield, while acoustic power density had less effect on the 3 responses. The optimum conditions were 15.6 min extraction time, 69 °C and 0.43 W/mL. The ultrasound extraction produced better extracts in term of enzyme inhibition and RSA (lower IC50: 14.25 μg/mL enzyme, 3.17 μg/mL RSA), in comparison to Soxhlet and maceration combined with heat, and a more rapid extraction with increased yield of extraction. Ultrasound kanuka extracts can potentially complement existing AD treatment. [ABSTRACT FROM AUTHOR]

Woody plant expansion into grasslands is widespread, driven by both successions to dominance by native woody species or invasion by non-native woody species. These shifts from grass- to woody-dominated systems also have profound effects on both above- and belowground communities and ecosystem processes. Woody-plant expansion should also alter the functional composition of the soil biota, including that of nematodes, which are major drivers of soil food-web structure and belowground processes, but such belowground impacts are poorly understood. We determined whether succession by a widespread native (Kunzea ericoides) and invasion by a non-native woody species (Pinus nigra) into tussock grasslands affect the composition of nematode functional guilds and the structure of nematode-based food webs. Although increasing dominance by woody species in both systems altered the functional guild composition of the nematode community, we found contrasting responses of nematode functional guilds to the different dominant plant species. Specifically, nematode communities reflected conditions of resource enrichment with increasing K. ericoides tree cover, whereas communities became structurally simplified and dominated by stress-tolerant nematode families with increasing P. nigra tree cover. Because nematodes regulate both bacterial- and fungal-dominated food webs in soils, these shifts could in turn alter multiple ecosystem processes belowground such as nutrient cycling. Incorporating species' functional traits into the assessment of habitat-change impacts on communities can greatly improve our understanding of species responses to environmental changes and their consequences in ecosystems. [ABSTRACT FROM AUTHOR]

The article offers information on Kanuka (Kunzea ericoides), a member of the Kunzea family in Southern Australia and Tasmania. Topics include Kanuka oil in the treatment of acne and eczema, North Island commercial oil producing like Barrier Gold, Coromandel Mountains Tea Tree Oil Co. and Kanuka Oil NZ Ltd., and Kanuka essential oil is distilled from the foliage and branches of pruned trees, leaving the tree to regenerating quickly.

Highlights • Utilisation of mānuka and kānuka trees for industrial application are discussed. • Products of kānuka as much as mānuka possess almost similar characteristics. • Kānuka oil has viable immuno-stimulatory properties than that of mānuka. • Large avenues, beyond current products to be exploited commercially. Abstract This paper brings to light the current status of products from mānuka , (Leptospermum scoparium J.R.Forst. & G.Forst) and kānuka (Kunzea ericoides (A.Rich) Joy Thomps), and to show that kānuka products also have significant biological potency. Mānuka and kānuka are two native tea tree species found widely within New Zealand. Most research on these two plants was and still is, motivated by the medicinal value identified in the products such as essential oil. It was observed that unlike mānuka, which has extensive and in-depth research and reviews conducted on it, similar studies and appraisals on kānuka is lacking. The few available research outputs available on kānuka have proven that it is superior in terms of anti-inflammatory properties, hence more research and appraisal is required to demonstrate its potency. This review presents evidence that will help promote diversified utilisation of mānuka and kānuka and encourage commercialisation of the latter as much as is done for the former. [ABSTRACT FROM AUTHOR]

Highlights • Different grades of Bai Mudan white tea showed differential metabolite composition. • The grade variation of Bai Mudan white tea was revealed by multivariate analysis. • 21 Structurally-identified metabolites correlated with tea grade variation. • Non-targeted metabolomics could be used for Bai Mudan white tea grade evaluation. Abstract So far, the chemical quality of different grades of white tea has largely remained unexplored. The objective of this study was to establish a model for quality evaluation of different grades of Bai Mudan white tea. We applied non-targeted ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry in combination with multivariate analysis and analyzed four different grades of Bai Mudan white tea. We found that the metabolite composition from the super-grade and the first-grade shared higher similarity compared to the second-grade or the third-grade white tea, and the Partial Least Square-Discriminant Analysis model showed high capability to explain the sample variation (R2Y = 0.998, Q2 = 0.95 in negative ionization modes). In total, 93 metabolites were structurally identified, wherein 21 low abundant metabolites showed distinct changes in abundance that were closely correlated with tea grade variation. These findings suggested their potential as markers to discriminate different grades of Bai Mudan white tea. [ABSTRACT FROM AUTHOR]

Highlights • Formation of and changes in white tea aroma were systematically investigated. • Amino acids and glycosidically bound volatiles promoted white tea aroma formation. • Aroma-related key genes participated in the regulation of white tea aroma formation. • Both long withering and drying contribute to white tea aroma characteristics. Abstract The formation of and dynamic changes in aroma during white tea processing have not previously been systematically investigated. In this study, advanced comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry was employed to investigate the mechanism of white tea aroma formation. A total of 172 volatiles were identified and mainly comprising endogenous volatiles, which displayed diverse change trends during the withering period. In this process, free aroma precursor amino acids and glycosidically bound volatiles (GBVs) were found to contribute to the formation of white tea aroma, with the differential expression of aroma-related key genes accounting for various accumulation of endogenous volatiles and GBVs. In addition, the drying was also shown to play an important role in the formation of white tea aroma. Our study provides the first characterization of white tea aroma formation and establishes a theoretical basis for quality control during white tea processing operations. [ABSTRACT FROM AUTHOR]

New Zealand manuka ( Leptospermum scoparium ) and kanuka ( Kunzea ericoides ) honeys contain a unique array of chemical markers useful for chemical fingerprinting. We investigated the presence of 13 potential marker compounds in nectars of the major honey crop species. We confirmed that leptosperin, lepteridine, 2′-methoxyacetophenone, and 2-methoxybenzoic acid are exclusive to manuka nectar whereas lumichrome is unique to kanuka nectar. 3-Phenyllactic acid and 4-hydroxyphenyllactic acid are present in manuka and kanuka nectars. Leptosperin, lepteridine, 3-phenyllactic acid, and 4-hydroxyphenyllactic acid are chemically stable over prolonged storage, but not 2-methoxybenzoic acid and 2′-methoxyacetophenone. Accordingly, leptosperin and lepteridine are definitive chemical markers for authentication of manuka honey. An optimal concentration cut-off was established for the floral source-specific markers: leptosperin (94 mg/kg), lepteridine (2.1 mg/kg), 2′-methoxyacetophenone (2.0 mg/kg) for manuka honey, and lumichrome (4.5 mg/kg) for kanuka honey. The use of leptosperin and lepteridine as fluorescence markers for manuka honey authentication is reinforced. [ABSTRACT FROM AUTHOR]

Lead (Pb) and cadmium (Cd) are toxic metals occurring commonly in the human environment that show mutagenic, genotoxic and carcinogenic effects. Dietary components could prevent heavy metals intoxication by reducing their accumulation in the body. The purpose of the study was to check possible protective effect of regular consumption of white, black, red, or green tea on bone metabolism during long-term exposure to Pb and Cd in adult rats. The 12 week-long exposure to Pb and Cd (50 mg Pb and 7 mg Cd/kg of the diet) in a rat model was studied. Twelve-week-old adult male Wistar rats were randomly divided into a negative control group (Pb and Cd exposure without tea), a control (without Pb and Cd and teas), and groups co-exposed to Pb and Cd and supplemented with green, red, black, or white tea (n=12 each group). The experiment lasted for 12 weeks. The co-exposure to Pb and Cd led to the increase of bone resorption depending on the tea treatment, which was confirmed by the mechanical testing and histomorphometrical examination of cancellous bone. Pb and Cd influenced mechanical strength, reduced the densitometric and geometric parameters and the thickness of growth plate and articular cartilages. Concluding, white tea exerted the best protective effect on bone tissue and hyaline cartilage against heavy metal action. [ABSTRACT FROM AUTHOR]

The use of nontoxic biological compounds in the synthesis of nanomaterials is an ecofriendly and cost-effective approach in nanotechnology. The present work was carried out to develop silver nanoparticles (Ag-NPs) by a green method using white tea ( Wt ) extract as reducing agent for reduction of silver nitrate as silver precursor into the lamellar space of inorganic polymer montmorillonite (Mt) as an effective protective reagent and support as well. The bioformed Wt /Ag@Mt nanocomposite (NCs) was compared with pure biosynthesized Wt /Ag-NPs under free stabilizer condition and effect of Mt stabilizer on antioxidant, cytotoxicity and structural properties were also investigated. The prepared Wt /Ag-NPs and Wt /Ag@Mt-NCs were characterized by UV–vis spectroscopy, FTIR, XRD, TEM, SEM and EDX. The interlamellar space limits were without many changes, therefore Ag-NPs formed on the exterior surface of Mt. The XRD study showed that the particles are crystalline structure in nature, with a facecentered cubic (fcc) structure. The TEM result shows the bioformed Ag-NPs are spherical in shapes with mean particle size of 19.77 ± 3.82 for Wt /Ag-NPs and 15.87 ± 2.38 nm for Wt /Ag@Mt-NCs. In vitro cytotoxicity studies on MOLT-4 cells, a dose dependent toxicity with non-toxic effect of concentration below 40 μg/mL was shown. The outcome shows that IC 50 of our green synthesized Wt /Ag@Mt-NCs was 0.0039 in comparison to 2.13329 for Doxorubicin and 0.013 μM for Cisplatin which is much better than IC 50 of these anticancer drugs and more active than them for MOLT-4 cell line. Antioxidant activity indicated that they can be applied as potential radical scavenger and also showed that DPPH activity increased in a dose dependent manner. The bio-synthesized nanoparticles can potentially useful in pharmaceutical and biomedical applications. [ABSTRACT FROM AUTHOR]

Background and Objectives: Honey has various biological and pharmacological activities and has been used as treatment against various inflammatory diseases. The aim of this study was to compare the anti-inflammatory characteristics of manuka, kanuka, and black locust honey. Materials and Method: Peripheral blood mononuclear cells (PBMCs) from healthy human volunteers were isolated and then stimulated with lipopolysaccharide (LPS) with or without pre-treatment of various concentrations of honey for 72 hours. The cytotoxic effects of honeys were measured using an aqueous cell proliferation kit, and the supernatants were analyzed for interleukin-5 (IL-5), IL-10, interferon-γ (INF-γ), and tumor necrosis factor-α (TNF-α) using an enzyme-linked immunosorbent assay. Results: Samples of 1% manuka and kanuka honey were found to have cytotoxic effects on PBMCs. Honey itself enhanced the production of IL-10 and TNF-α production. Manuka and kanuka honeys suppressed LPS-induced IL-10 and INF-γ production, while black locust honey only suppressed IL-10 production from PBMCs. Conclusion: Honeys had immunomodulatory properties of both immunostimulatory and immunosuppressive effects on PBMCs. Different honeys might have different immune modulatory functions due to their different components. [ABSTRACT FROM AUTHOR]

The aim of the study was to generate compositional data for authentic white tea samples from China to serve as a starting point for a database and aid the definition of white teas. Quantitative data for the major catechins, hydrolysable tannins, phenolic acids, flavonol glycosides, alkaloids and theanine in 58 Chinese white teas were obtained based on HPLC methods Data for the major theaflavins in white teas are provided for the first time. Measurements of 29 metabolomics showed there were distinct differences among the different types of white teas such as silver needle white tea (BHYZ), white peony white tea (WP), ShouMei white tea (SM) and compressed brick white tea (CP). In our investigation, catechins, hydrolysable tannins, phenolic acids, theanine and caffeine had higher levels in early spring produced BHYZ than teas in late spring produced WP and autumn produced ShouMei. Theaflavins were found highest in mature autumn white tea samples, and lower in spring. Flavonol glycosides showed a different aglycone pattern. In early spring harvest BHYZ, kaempferol was the most abundant aglycone followed by quercetin and myricetin, while in autumn harvest ShouMei and CP samples, quercetin was most abundant followed by kaempferol and myricetin. [ABSTRACT FROM AUTHOR]

The fluorescence characteristics of various New Zealand honeys were investigated to establish if this technique might detect signatures unique to manuka ( Leptospermum scoparium ) and kanuka ( Kunzea ericoides ) honeys. We found unique fluorescence profiles for these honeys which distinguished them from other New Zealand honey floral types. Two excitation–emission (ex–em) marker wavelengths each for manuka and kanuka honeys were identified; manuka honey at 270–365 (MM1) and 330–470 (MM2) nm and kanuka honey at 275–305 (KM1) and 445–525 (KM2) nm. Dilution of manuka and kanuka honeys with other honey types that did not possess these fluorescence profiles resulted in a proportional reduction in fluorescence signal of the honeys at the marker wavelengths. By comparison, rewarewa ( Knightia excelsa ), kamahi ( Weinmannia racemosa ), and clover ( Trifolium spp.) honeys did not exhibit unique fluorescence patterns. These findings suggests that a fluorescence-based screening approach has potential utility for determining the monoflorality status of manuka and kanuka honeys. [ABSTRACT FROM AUTHOR]

The influence of commonly used steeping times and temperatures, as well as leaf size on the antioxidant activity and sensory attributes of tea were studied. Five unblended white and green tea samples from China and Malawi, infused in hot (70 °C and 90 °C; 7 min) or cold water (room temperature: 15, 30, 60, or 120 min) either as whole leaves or as milled, were analyzed. Total phenolic and flavonoid contents as well as antioxidant power (ABTS assay) were measured. The results show that the maximum extraction efficiency occurs with cold water for 120 min and with hot water at 90 °C and that only in the case of teas from whole, large leaves, the extraction was greater in cold than in hot infusions. Moreover, tea infusions prepared from milled leaves have the greatest antioxidant activity. In the sensory evaluation of some of the tea infusions, white teas were perceived more fragrant than green ones and were judged as the most favorite by the majority of the judges, especially for the brew prepared in cold water from whole leaves; all infusions obtained from the milled leaves in fact have a more bitter and astringent taste. [ABSTRACT FROM AUTHOR]

Redbay ambrosia beetle, Xyleborus glabratus Eichhoff, is an exotic wood borer and the primary vector of Raffaelea lauricola, a symbiotic fungus that causes laurel wilt. This lethal disease has decimated native redbay [Persea borbonia (L.) Sprengel] and swampbay [Persea palustris (Rafinesque) Sargent] throughout southeastern U.S. forests, and currently threatens avocado (Persea americana Miller) in Florida. To curtail the spread of laurel wilt, effective attractants are needed for early detection of the vector. Phoebe oil lures were the best known attractant for X. glabratus, but they are no longer available. The current detection system uses manuka oil lures, but previous research indicated that manuka lures have a short field life in Florida. Recently, cubeb oil was identified as a new attractant for X. glabratus, and cubeb bubble lures are now available commercially. This study compared trapping efficacy and field longevity of cubeb and manuka lures with phoebe lures that had been in storage since 2010 over a 12-wk period in south Florida. In addition, terpenoid emissions were quantified from cubeb and manuka lures aged outdoors for 12 wk. Captures were comparable with all three lures for 3 wk, but by 4 wk, captures with manuka were significantly less. Equivalent captures were obtained with cubeb and phoebe lures for 7 wk, but captures with cubeb were significantly greater from 8 to 12 wk. Our results indicate that cubeb bubble lures are the most effective tool currently available for detection of X. glabratus, with a field life of 3 months due to extended low release of attractive sesquiterpenes, primarily α-copaene and α-cubebene. [ABSTRACT FROM PUBLISHER]

Honeydew is abundant in many ecosystems and may provide an alternative food source (a buffer) for pollinators during periods of food shortage, but the impact of honeydew on pollination systems has received little attention to date. In New Zealand, kānuka trees (Myrtaceae: Kunzea ericoides (A. Rich) Joy Thompson) are often heavily infested by the endemic honeydew-producing scale insect Coelostomidia wairoensis (Maskell) (Hemiptera: Coelostomidiidae) and the period of high honeydew production can overlap with kānuka flowering. In this study, we quantified the sugar resources (honeydew and nectar) available on kaāuka and recorded nocturnal insect activity on infested and uninfested kaāuka during the flowering period. Insects were abundant on infested trees, but flowers on infested trees received fewer insect visitors than flowers on uninfested trees. There was little evidence that insects had switched directly from nectar-feeding to honeydew-feeding, but it is possible that some omnivores (e.g., cockroaches) were distracted by the other honeydew-associated resources on infested branches (e.g., sooty molds, prey). Additional sampling was carried out after ka āuka flowering had finished to determine honeydew usage in the absence of adjacent nectar resources. Moths, which had fed almost exclusively on nectar earlier, were recorded feeding extensively on honeydew after flowering had ceased; hence, honeydew may provide an additional food source for potential pollinators. Our results show that honeydew resources can impact floral visitation patterns and suggest that future pollinator studies should consider the full range of sugar resources present in the study environment. [ABSTRACT FROM AUTHOR]

Anthropogenic fire has transformed New Zealand's vegetation. Small-scale historical Mori fires in the forests of Te Urewera National Park, North Island, initiated forest successions that were dominated early on by Kunzea ericoides (Myrtaceae), and later by Knightia excelsa (Proteaceae) and Weinmannia racemosa (Cunoniaceae). Previous work in these forests suggested that the more recent of these successions, initiated after the arrival of deer in the late 19th century, have failed to recover to pre-fire composition and structure. This failure was attributed to browsing pressure that prevented palatable canopy tree species such as Weinmannia racemosa establishing at adequate densities. We tested this hypothesis by quantifying changes in forest structure, tree species composition and above-ground tree biomass between 1980 and 2010 using permanent forest plots in three successional communities. The three communities were dominated by (1) Kunzea ericoides - kanuka, (2) Knightia excelsa - rewarewa, and (3) Weinmannia racemosa - kamahi. We show that above-ground biomass increased in all communities between 1980 and 2010, and did so most strongly in the first two communities. However, tree species composition changed little over the same time except for a more than three-fold increase in tree fern abundance in the kanuka community where they are now co-dominant with Kunzea ericoides. Recruitment of trees of canopy species was very low (⩽ 0.06% per year) relative to mortality (1.1-3.9% per year) in all three communities. The proportional increase in above-ground biomass observed in the kanuka community was low relative to the large proportional increase in basal area. This occurred because of the higher abundance of tree ferns in 2010 plots that have low stem tissue density. The minimal compositional change over 30 years in these communities and paucity of recruitment of trees of canopy species point to arrested succession. Without management intervention to increase tree recruitment rates of canopy species, forest successions in this region will be characterised by high tree fern abundance, low biomass at local scales, and limited transitions to tall forest communities. [ABSTRACT FROM AUTHOR]

Carbon storage by trees and soil in urban areas is of increasing interest as a potential greenhouse gas mitigation measure. Our objectives were to (1) quantify carbon accumulation in above- and below-ground tree biomass, organic layer and mineral soil (0-5 cm) of a 27-year-old planted forest in Auckland and (2) compare the sequestration potential of urban trees with natural shrublands and forests in New Zealand. A mixed-species allometric equation for urban-grown native trees was developed on the basis of the tree biomass of 21 trees belonging to four species (Corynocarpus laevigatus, Kunzea ericoides, Pittosporum eugenioides, P. tenuifolium). Our allometric equation and a recently developed mixed-species equation for New Zealand native forest species produced similar results. A total of 45.9 Mg C ha-1 was stored in above- and below-ground tree biomass in our Auckland park, equating to an average annual carbon sequestration rate of 1.7 Mg C ha-1. This rate is within the range reported for New Zealand shrublands. Despite the adverse conditions posed by some urban environments (e.g. poor-quality soil, contamination), planted urban forests can sequester carbon at similar rates to natural vegetation in New Zealand. [ABSTRACT FROM AUTHOR]

The addition of a trap baited with manuka oil or longer lasting cubeb oil lures (Hanula et al. 2013) along with those baited with ethanol for surveys targeting detection of non-native, invasive Curculionidae could improve these surveys by also targeting the destructive redbay ambrosia beetle. [ABSTRACT FROM AUTHOR]

Seedlings of the shrub kāanuka (Kunzea ericoides var. ericoides (A. Rich) J. Thompson) and the pasture grass brown top (Agrostis capillarus L.) were grown in intact soil cores in climate-controlled cabinets to analyse the thermal response of leaf-level carbon exchange at four levels of volumetric soil water content (θ). The objective was to resolve the combined effects of relatively rapid and short-term changes in θ and temperature on the thermal responses of both photosynthesis and respiration in these two contrasting plant types. Results showed that θ had a greater effect on the short-term temperature response of photosynthesis than the temperature response of respiration. The optimum value of θ for net photosynthesis was around 30% for both plants. The photosynthetic capacity of kāanuka and the grass declined significantly when θ fell below 20%. The temperature sensitivity of photosynthesis was low at low soil water content and increased at moderate to high soil water content in both plant types. Statistical analysis showed that the temperature sensitivity of photosynthetic parameters was similar for both plant types, but the sensitivity of respiratory parameters differed. Respiratory capacity increased with increasing soil water content in kāanuka but declined significantly when θ fell below 15%. There was no significant influence of soil water content on respiratory capacity in the grass. Collectively, our results indicate that θ influenced the temperature sensitivity of photosynthesis and respiration, and altered the balance between foliar respiration and photosynthetic capacity in both plant types. [ABSTRACT FROM AUTHOR]

The essential oil composition of three Myrtaceous species (Leptospermum petersonii, Leptospermum scoparium and Kunzea ericoides) belonging to the tea tree group were analysed using gas chromatography coupled to mass spectrometry (GC–MS). The major compounds determined from the mean±SD of the monthly samples collected for one calendar year in L. petersonii are citronellal (11.4±4.3%), citronellol (17.5±7.1%), neral (19.7±1.6%) and geranial (34.7±3.3%). The major compounds in L. scoparium are eudesma-4(14)-11-diene (11.6±2.4%), α-selinene (10.4±2.3%) and (E)-methyl cinnamate (12.6±3.8%). The major compounds in K. ericoides are α-pinene (37.6±6.3%) and p-cymene (13.5±4.1%). The essential oils show some promising antimicrobial activity against selected micro-organisms when investigated using the minimum inhibitory concentration assay. Highest sensitivities were noted for the Brevibacteria (lowest MIC value of 0.06mg/ml), a genus associated with foot odour. When the different essential oils were combined in various ratios and tested against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, a predominantly additive effect was noted. [ABSTRACT FROM AUTHOR]

Background: Manuka honey is recognized for it's health-promoting properties and it's use in medicine is well documented. However, the actions of Manuka honey are limited by rapid digestion and the inactivation of bioactive components such as methylglyoxal. Cyclodextrins are naturally occurring glucose rings that improve stability and bioactivity of products. This study investigates the tolerability and bioactivity of α-cyclodextrin-complexed Manuka honey called Manuka Honey with CycloPower ™. Methods: The antibacterial properties of Manuka honey complexed with α-cyclodextrin (Manuka honey with Cyclopower™) were compared to uncomplexed Manuka honey against a range of common organisms using standard measurements of minimum inhibitory (MIC) and bactericidal (MBC) concentrations. Time course growth measurements were determined using a sublethal concentration of 2% w (honey solids)/v and measuring the area under the growth curve. Results: In tube MIC assays, Manuka honey completely inhibited Staphylococcus aureus (MSSA and MRSA), Streptococcus pyogenes, Helicobacter pylori and Moraxella catarrhalis at concentrations of 10% w/v or less, with MIC values decreasing as the methylglyoxal content of the honeys increased from 100 to 550 mg/kg. MIC values at a given methlyglyoxal level were also decreased for S. pyogenes, M. catarrhalis and H. pylori by complexing the Manuka honey with α-cyclodextrin. Pseudomonas aeruginosa was not inhibited by any of the Manuka honey or Cyclopower treatments at the concentrations tested (2-10% w/v). Manuka honey with CyclopowerTM had an increased bacteriostatic action against S. aureus, MRSA and P. aeruginosa compared with Manuka honey. Conclusions: This study concludes that Manuka honey is an effective antibacterial agent that can be enhanced by complexing with α-cyclodextrin. [ABSTRACT FROM AUTHOR]

Redbay ambrosia beetle Xyleborus glabratus is an invasive wood boring beetle that has become established in the southeastern U. S.A. and transmits a fungus Raffaelea lauricola that causes lethal laurel wilt. Among susceptible Lauraceae hosts are redbay Persea borbonia and avocado Persea americana., There is a crucial need for detection of this pest as it moves into new areas. Consequently, our goal was to create a better lure for the monitoring and control of redbay ambrosia beetle., We analyzed volatile emissions of R. lauricola, created a synthetic odour blend based on this analysis and tested this odour blend as a potential attractant in a redbay forest infested with X. glabratus. The synthetic Raffaelea odour blend was not attractive to the beetles by itself. However, it synergistically increased attraction to host-mimic volatiles., We tested four commercial release devices for dispensing Raffaelea odour at various release rates. Two prototypes with the highest release rate, when paired with commercial manuka oil lures, captured more beetles than manuka oil lures alone. These results indicate that a synthetic blend of volatiles based on the odour of the symbiotic fungus of X. glabratus may be useful for the development of more sensitive monitoring lures for this invasive pathogen vector. [ABSTRACT FROM AUTHOR]

The aim of this work was the evaluation of QuEChERS extraction method for polycyclic aromatic hydrocarbon (PAH) determination in various types of tea. In the experiment, different kinds of extraction solvents, sorbents and a final method of sample preparation were compared. The final extracts were analysed by gas chromatography-selected ion monitoring-mass spectrometry. The results suggest that acetonitrile extraction, clean up with SAX and final liquid-liquid extraction was the best combination giving the most purified extracts and acceptable compound recoveries for different types of teas. In the study of real samples, compounds belonging to light PAHs were mostly detected, and heavy polycyclic aromatic hydrocarbons, including benzo[a]pyrene, were not identified in any of samples. [ABSTRACT FROM AUTHOR]

Highlights: [•] WEWT protects Clone 9 cells death induced by H2O2. [•] Sixteen phenolic compounds are identified and present in WEWT. [•] GSH and antioxidant enzymes contribute the protection of oxidative stress. [•] The defence mechanisms of WEWT are maintenance of the normal redox status. [Copyright &y& Elsevier]

Highlights: [•] 31 New Zealand mānuka honeys of varying UMF were analysed for flavonoid content. [•] Pinobanksin, pinocembrin, luteolin and chrysin were 61% of the flavonoid content. [•] 2-formyl-5-(2-methoxyphenyl)-pyrrole, (1), was isolated and characterised. [•] 1 was weakly correlated with non-peroxide antibacterial activity as was luteolin. [•] 1 and luteolin do not have an individual or synergic contribution to bioactivity. [Copyright &y& Elsevier]

Abstract: The present study explored what effect manufacturing has on the antioxidant properties of teas coming from a single cultivar but processed differently to give a white, two black (Orthodox and CTC) and two green (low-caffeine and non-decaffeinated) teas. Total phenol (TPC), flavonoids (TFC), theaflavins, individual catechins content, and chelating activity were also investigated. Using the ABTS, ORAC and LDL assays the following ‘antioxidant profile’ was obtained: green≥low-caffeine green>white≥black Orthodox>black CTC, with statistically significant correlation between ORAC and LDL assays (r2 =0.444, p=0.0067), whereas TPC and TFC significantly correlate with the ABTS one (r2 =0.871, p=0.000 and r2 =0.438, p=0.007, respectively). Metal chelating activity, which was lowest in the green teas, does not correlate with antioxidant activity but appears to be influenced by theaflavins content. The results contribute to better understand how the manufacturing process influences the antioxidant activity of tea when variables (geographical region, environmental conditions, cultivar type, plucking techniques) are kept to a minimum. Secondly, we show that novel African green, white and black Orthodox teas, made from tea varieties typically used in black CTC tea production, may have potential health benefits comparable with commonly consumed teas. [Copyright &y& Elsevier]