New cytotoxic triterpenoid saponins from the whole plant of Clematis lasiandra Maxim

Four new oleanane type triterpenoid saponins (1–4) and three known saponins (5–7) were isolated from the whole plant of Clematis lasiandra Maxim. The structures of the four new compounds were elucidated as 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-β-d-xylopyranosyl hederagenin (1), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl oleanolic acid 28-O-β-d-glucopyranosyl ester (2), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl hederagenin (3) and 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-α-l-arabinopyranosyl hederagenin (4) on the basis of extensive spectroscopic analysis and chemical evidence. Compounds 1–7 were evaluated for their cytotoxicity against human tumor cell lines HL-60, Hep-G2 and SGC-7901, and all of the evaluated saponins showed significant cytotoxicity to those three tumor cell lines with IC₅₀ in the range from 1.40 to 19.50 μmol/L except for compounds 2 and 6.     

A new glucomannan from Bletilla striata: Structural and anti-fibrosis effects

A novel water-soluble polysaccharide, designated Bletilla striata polysaccharide b (BSPb), was isolated from a traditional Chinese medicinal herb, Bletilla striata. The crude polysaccharide was obtained by hot water extraction and purified by ion-exchange chromatography. The molecular weight was 260 kDa as determined by HPGPC (high performance gel permeation chromatography). Monosaccharide analysis showed that BSPb contained glucose and mannose with a molar ratio of 3:1. Methylation and spectroscopic analyses with 1D and 2D NMR spectroscopy showed that the backbone of BSPb is mainly composed of (1 → 2)-linked α-d-mannopyranose and (1 → 4)-linked β-d-glucopyranose residues. In this study, BSPb plays an important role in protection against the renal fibrosis effect, which is probably mediated by down-regulated TGF-β RI, TGF-β RII, and α-SMA in vitro.     

The inhibition of resveratrol to human skin squamous cell carcinoma A431 xenografts in nude mice

Squamous cell carcinoma (SCC) is one of the commonest dermatological malignancies. Resveratrol (Res) is one type of polyphenolic compound which was first identified from the roots of Veratrum grandinorum in 1940. The previous studies found that Res can promote apoptosis of a variety of tumor cell, especially SCC cells. However it is rare to study the inhibition mechanism of Res in the animal model. In this study, through the establishment of human cutaneous SCC A431 xenografts in nude mice, we observed Res inhibition effect and investigated the inhibition mechanism by checking the expression of apoptosis-related factors, p53, ERK and survivin. The results showed that the xenograft volume and weight of Res groups were less than those of the control groups (P < 0.05), but the net body mass of nude mice of Res groups was not significantly different from the control groups (P > 0.05). The apoptotic index of Res groups were significantly higher than the control groups (P < 0.05). The protein and mRNA expression of p53 and ERK were statistically positively correlated (P < 0.05) and significantly increased in Res high- and medium-dose groups compared with the control groups (P < 0.05). Moreover, the protein and mRNA expression of SVV were negatively correlated with p53 (P < 0.05) and lower than the control groups (P < 0.05). The results demonstrate Res inhibitory effect and indicate that the inhibition mechanism of Res is to upgrade the protein and mRNA expression of p53 and to downgrade the protein and mRNA expression of SVV, thus inducing the apoptosis of tumor cells.     

Molecular mechanisms of citrus flavanones on hepatic gluconeogenesis

It is well known that hyperglycaemia is the initiating cause of tissue damage associated with type 2 diabetes mellitus and that enhanced hepatic gluconeogenesis may account for the increase in blood glucose levels. The purpose of this work was to investigate the possible actions and mechanisms of three related citrus flavanones, namely hesperidin, hesperetin and naringenin, on hepatic gluconeogenesis and related parameters using isolated perfused rat liver. Hesperetin and naringenin (but not hesperidin) inhibited gluconeogenesis from lactate plus pyruvate, alanine and dihydroxyacetone. The inhibitory effects of these flavanones on gluconeogenesis from lactate and pyruvate (hesperetin IC₅₀ 75.6 μM; naringenin IC₅₀ 85.5 μM) as well as from alanine were considerably more pronounced than those from dihydroxyacetone. The main cause of gluconeogenesis inhibition is the reduction of pyruvate carboxylation by hesperetin (IC₅₀ 134.2 μM) and naringenin (IC₅₀ 143.5 μM) via inhibition of pyruvate transport into the mitochondria. Secondary causes are likely inhibition of energy metabolism, diversion of glucose 6-phosphate for glucuronidation reactions and oxidation of NADH by flavanone phenoxyl radicals. The influence of the structural differences between hesperetin and naringenin on their metabolic effects was negligible. Analytical evidence indicated that the presence of a rutinoside moiety in hesperidin noticeably decreases its metabolic effects, confirming that hesperetin and naringenin interact with intracellular enzymes and mitochondrial or cellular membranes better than hesperidin. Thus, the inhibition of the gluconeogenic pathway by citrus flavanones, which was similar to that of the drug metformin, may represent an attractive novel treatment strategy for type 2 diabetes.     

The protective activity of imperatorin in cultured neural cells exposed to hypoxia re-oxygenation injury via anti-apoptosis

Apoptosis is believed to play important roles in neuronal cell death associated with cerebral ischemia. We now provided evidence that imperatorin (IMp), the main composition of the dried root or rhizome of R Radix Angelicae Dahuricae, took advantage on oxygen glucose deprivated/reperfusion (OGD-R) SH-SY5Y cell line through neuronal apoptosis inhibition. Our data had shown that imperatorin reduced the number of apoptosis cells after OGD-R, this effect was associated with the inhibition of the apoptosis factors Bax and caspase-3, and the upregulation of anti-apoptosis factor Bcl-2. In the meantime, the protective factor BDNF was upregulated significantly by imperatorin treatment. In our experiment in vivo, imperatorin decreased the infract volume significantly in dose of 5 mg/kg and 10 mg/kg, and the behavior ability was increased in the 10 mg/kg of imperatorin. Our observations show that imperatorin exerted protective effect on cerebral ischemia both in vitro and in vivo, this effect is associated with its anti-apoptosis function.     

Inactivation of jack bean urease by scutellarin: Elucidation of inhibitory efficacy,kinetics and mechanism

In the present study, the inactivation effect of scutellarin (SL) on jack bean urease was investigated to elucidate the inhibitory potency, kinetics and mechanism of inhibition. It was revealed that SL acted as a concentration- and time-dependent inactivator of urease characteristic of slow-binding inhibition with an IC₅₀ of 1.35 ± 0.15 mM. The rapid formation of the initial SL–urease complex with an inhibition constant of K_i = 5.37 × 10^− 2 mM was followed by a slow isomerization into the final complex with the overall inhibition constant of K_i* = 3.49 × 10^− 3 mM. High effectiveness of thiol protectors, such as L-cysteine (L-cys), 2-mercaptoethanol (2-ME) and dithiothreitol (DTT) significantly slowed down the rate of inactivation, indicating the strategic role of the active site sulfhydryl group in the blocking process. While the insignificant protection by boric acid and fluoride from the inactivation further confirmed that the active site cysteine should be obligatory for urease inhibition, which was also rationalized by the molecular docking study. The inhibition of SL on urease proved to be reversible since SL-blocked urease could be reactivated by DTT application and multidilution. The results obtained indicated that urease inactivation resulted from the reaction between SL and the sulfhydryl group.     

Effects of cycloartane saponins from hairy roots of Astragalus membranaceus Bge., on human tumor cell targets

For the first time three different natural compounds, isolated from hairy roots of Astragalus membranaceus, cultivated in airlift bioreactor were tested for their cytotoxic potential and apoptosis induction in a panel of human tumor cell lines. Root cultures, cultivated in bioreactor gave 18.5 g l^? 1 dry wt roots with the highest astragaloside production in vitro up to now — 1.64% (astragaloside I), 1.12% (astragaloside II) and 1.08% (astragaloside III). In this manner the production in airlift bioreactor can be used as means of reliable supply of cycloartane saponins to extend the research to human clinical studies.     

Utilization and traditional strategies of in situ conservation of iroko (Milicia excelsa Welw. C.C. Berg) in Benin

Socio-cultural surveys were carried out on the basis of a questionnaire administered on 346 respondents in order to investigate cultural and ethnobotanic uses of Milicia excelsa in Benin.M. excelsa contributes to cure 45 human diseases. The different parts of the tree used are leaves (30.3%), bark (25.8%), root (23.6%), latex (10.1%), flaking bark (6.7%), wood, calcium concentrated in old trees, and gum (1.1% each). Fruits or seeds are rarely used. Six different forms of utilization were recorded: soaking (46.3%), bark or leaves decoction (32.8%), herb tea (11.9%), powder (6.0%), leaves or bark grounded and rolled up into ball (1.5%), component of offering to fetish (1.5%). Iroko wood is also used in carpentry and joinery for construction purposes; furniture as well as for building boats/canoes.Iroko tree is used as the conservatory of cultural values and incarnates many divinities, which differ significantly from one province to another (χ² = 1830.27; d.f. = 25; P < 0.01%). There is a significant difference between the provinces in respect of the recognition of the species (χ² = 268.71; d.f. = 17; P ≤ 0.01%) and the population awareness about iroko as a sacred tree also varied from one province to another (χ² = 308.66; d.f. = 27; P ≤ 0.01%).Veneration of the tree is the main approach of its conservation by local people. M. excelsa is conserved on farm, in sacred groves, in public places and in cemeteries. The different sacred objects used to symbolize the divinities incarnated by iroko are: pottery (36.36%), iron (11.11%), calabash (4.04%), candle (2.02%), piece of cloth (18.18%), sacrifice (13.13%), piece of money (3.0%), stone (2.05%), glassware (broken bottle, 2.02%), and convent (8.08%). There is a highly significant difference between provinces as far as the sacred objects are concerned (χ² = 183.037; d.f. = 19 and P < 0.001%). The conservation purposes also vary significantly from one region to other (χ² = 894.47; d.f. = 31; P < 0.01%).     

Structural characterization and antioxidant activity of a low-molecular polysaccharide from Dendrobium huoshanense

The present study aimed at investigating the structural features and antioxidant activities of a polysaccharide fraction (DHP1A) obtained from Dendrobium huoshanense, a precious herb medicine in China. DHP1A mainly consisted of mannose (Man), glucose (Glc) and a trace of galactose (Gal), with a molecular weight of 6700 Da. Its backbone contained (1 → 4)-linked α-D-Glcp, (1 → 6)-linked α-D-Glcp and (1 → 4)-linked β-D-Manp, with a branch of terminal β-D-Galp. The in vitro antioxidant evaluation revealed that DHP1A had a remarkable inhibition effect on the FeCl₂-induced lipid peroxidation. Furthermore, DHP1A pretreatment decreased the production of malondialdehyde (MDA), and restored the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), as well as the level of glutathione (GSH) in the livers of CCl₄-treated mice. These results suggested that DHP1A was a potential antioxidant component in D. huoshanense.     

Modulation of COX,LOX and NFκB activities by Xanthium spinosum L. root extract and ziniolide

Xanthium spinosum L. (Asteraceae) is a medicinal weed distributed worldwide. Many of its diverse ethnopharmacological uses – namely diarrhoea, inflammation, liver disorders, snake bite and fever – are linked – at least in part – to an uncontrolled release of arachidonic acid metabolites. The crude extract of X. spinosum roots from Jordanian origin dose-dependently inhibited the 5-LOX (IC₅₀ ≅ 10 μg/mL), COX-1(IC₅₀ ≅ 50 μg/mL), and 12-LOX (IC₅₀ ≅ 170 μg/mL) enzymatic pathways in intact pro-inflammatory cells. A direct activity at the level of PLA₂ is not probable, but the extract induced the synthesis of the anti-inflammatory eicosanoid 15(S)-HETE, which may in turn inhibit this enzyme. 5-LOX bioguided fractionation of the crude extract led to the isolation of ziniolide, a known 12,8-guaianolide sesquiterpene lactone, from the hydro-alcoholic fraction of the n-hexane extract (IC₅₀ = 69 μM). Both the plant extract and ziniolide are in vitro inhibitors of the phorbol-induced NFκB activation, a key regulator of the arachidonic pathway.     

Hormone-sensitive lipase is involved in the action of hydroxysafflor yellow A (HYSA) inhibiting adipogenesis of 3T3-L1cells

BackgroundSafflor yellow A (SY) has been demonstrated to be beneficial to cardiovascular system. Our previous study showed that hydroxysafflor yellow A (HSYA), a main component of SY, could increase peroxisome proliferator-activated receptor γ mRNA expression. In this study, we investigate the effect of HSYA on the proliferation and adipogenesis of mouse 3T3-L1 preadipocytes.MethodsThe proliferation and adipogenesis of 3T3-L1 cells treated with HSYA was studied by 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) spectrophotometry, Oil Red O staining and intracellular triglyceride assay methods. HSL mRNA expression and promoter activity were studied by real-time quantitative RT-PCR, transient transfection and dual luciferase reporter gene methods.ResultsHSYA (0.1 mg/L) significantly inhibited the proliferation of 3T3-L1 cells when compared with control cells in 8 h. This effect was further enhanced with the extension time (24 to 96 h) and an increase of concentration of HSYA (1–10 mg/L). The maximal inhibitory action was observed at 0.1 mg/L HSYA in 72 h (86 ± 11.8% vs. 100 ± 4.1%, p < 0.01). HSYA notably reduced the amount of intracellular lipid and triglyceride content in adipocytes to 85% (1 mg/L) and 75% (100 mg/L) on Day 4 following the differentiation, respectively, while increased HSL mRNA expression and promoter activities to 2.7 fold and 1.55 fold, respectively (p < 0.01), in differentiated 3T3-L1 adipocytes.ConclusionsHSYA inhibits the proliferation and adipogenesis of 3T3-L1 preadipocytes. The inhibitory action of HYSA on adipogenesis may be due to the promotion of lipolytic-specific enzyme HSL expression by increasing HSL promoter activity.     

(−)-Carvone: Antispasmodic effect and mode of action

(−)-Carvone is a monoterpene ketone found in spearmint (Mentha spicata var. crispa) essential oil that is widely used as an odor and flavor additive. An intestinal antispasmodic effect was recently reported for (−)-carvone, and it has been shown to be more potent than its (+)-antipode. The mechanism of (−)-carvone action in the intestines has not been investigated. To gain a better understanding of the (−)-carvone antispasmodic effect, we investigated its pharmacological effects in the guinea pig ileum. Terminal portions of the ileum were mounted for isotonic contraction recordings. The effect of (−)-carvone was compared with that of the classical calcium channel blocker (CCB) verapamil. In isolated ileal smooth muscle, (−)-carvone did not produce direct contractile or relaxation responses and did not modify electrically elicited contractions or low K⁺-evoked contractions. The submaximal contractions induced by histamine (p < 0.001), BaCl₂ (p < 0.05), and carbachol (p < 0.01) were significantly reduced by (−)-carvone. The contractile response elicited by high concentrations of carbachol was reduced but not abolished by (−)-carvone. No additive action was detected with co-incubation of (−)-carvone and verapamil on carbachol-induced contraction. (−)-Carvone reduced the contraction induced by high K⁺ and was almost 100 times more potent than verapamil. Thus, (−)-carvone showed a typical and potent CCB-like action. Many effects described for both (−)-carvone and spearmint oil can be explained as a CCB-like mode of action.     

The economics of carbon sequestration through pest management: application to forested landbases in New Brunswick and Saskatchewan,Canada

This analysis employs a spruce budworm (Choristoneura fumiferana Clem.) decision support system to examine costs and benefits of sequestering (protecting) carbon in forests through pest management. We analyzed 24 alternative spruce budworm protection scenarios for outbreaks on Prince Albert Forest Management Area (PAFMA) in Saskatchewan and Crown License 1 in New Brunswick. Scenarios included two outbreak severities (moderate and severe), three protection frequencies (very aggressive—protecting every year of the outbreak; aggressive—protecting the peak 3 years of outbreak; and semi-aggressive—protecting every second year of outbreak), and four protection program sizes (10,000 ha, 25,000 ha, 100,000 ha, or 150,000 ha). Under a severe outbreak, the largest (150,000 ha), very aggressive protection scenario provided the highest net CO₂ protected at 24.95 million metric tons (Mt) in PAFMA and 29.19 Mt in License 1. This protection scenario also provided the highest net present value at $64.23 M and $91.36 M in PAFMA and License 1, respectively. On the other hand, benefit/cost ratios were maximized under the smallest (10,000 ha) protection size at 11.90 and 15.37 using the aggressive and semi-aggressive protection frequencies in PAFMA and License 1, respectively. Finally, the discounted cost per ton of CO₂ protected was minimized at $0.48 and $0.37 using the smallest aggressive and semi-aggressive protection frequencies in PAFMA and License 1, respectively. The comparable costs and benefits from the moderate outbreak scenarios were similar, but generally less than, the severe outbreak scenarios. These results provide forest managers with important information needed to justify such carbon sequestration programs on economic grounds.     

Xanthine oxidase inhibitory lanostanoids from Ganoderma tsugae

Two new lanostanoids, 3α-acetoxy-22-oxo-5α-lanosta-8,24-dien-21-oic acid, named tsugaric acid D (1) and 16α-hydroxy-3-oxo-5α-lanosta-6,8,24(24¹)-trien-21-oic acid, named tsugaric acid E (2) were isolated from the fruit bodies of Ganoderma tsugae. The structures 1 and 2 were determined by spectroscopic methods. Compound 1 and known compounds 3 and 6 exhibited significant inhibitory effects on xanthine oxidase (XO) activity with an IC₅₀ values of 90.2 ± 24.2, 116.1 ± 3.0, and 181.9 ± 5.8 μM, respectively. Known compound 5 was able to protect human keratinocytes against damage induced by UVB light, which showed 5 could protect keratinocytes from photodamage. The 1 and 5 μM 1 combined with 5 μM cisplatin, respectively, enhanced the cytotoxicity induced by cisplatin. It suggested that 1 and 5 μM 1 combined with low dose of cisplatin may enhance the therapeutic efficacy of cisplatin and reduce side effect and cisplatin resistant.     

Protection of chronic renal failure by a polysaccharide from Cordyceps sinensis

A water-soluble polysaccharide (CPS-2), isolated from the cultured Cordyceps sinensis, was obtained by hot-water extraction, anion-exchange and gel permeation chromatography. Its structural characteristics were investigated by PMP pre-column derivation, periodate oxidation, methylation analysis, FTIR and NMR spectroscopy. CPS-2 was found to be mostly of α-(1 → 4)-d-glucose and α-(1 → 3)-D-mannose, branched with α-(1 → 4,6)-d-glucose every twelve residues on average. CPS-2 had a molecular weight of 4.39 × 10⁴ Da. The protective effect of CPS-2 on the model of chronic renal failure was established by fulgerizing kidney. The changes in blood urea nitrogen and serum creatinine revealed that CPS-2 could significantly relieve renal failure caused by fulgerizing kidney.     

Influence of various in situ rainwater harvesting methods on soil moisture and growth of Tamarix ramosissima in the semiarid loess region of China

The influence of different in situ rainwater harvesting and moisture conservation methods on soil moisture storage and growth of Tamarix ramosissima was studied in the semiarid loess region of China from 2002 to 2004. The treatments included control (T1), trench (T2), saucer covered by plastic film (T3), bare ridge and bare furrow (T4), plastic-covered ridge and bare furrow (T5), and plastic-covered ridge and gravel-covered furrow (T6). The results indicated that soil water storage for the T5 and T6 was significantly higher than the control. The T6 treatments produced the highest amount of soil water storage, 18–137 mm more than the controls at soil depth of 0–100 cm and 40–75 mm at soil depth of 100–200 cm. No significant differences in soil water storage were found between the T2, T3, T4 and the control treatments at soil depth of 0–100 cm, but soil water storage at soil depth of 100–200 cm was significantly higher for the T2, T3, T4 treatment than the control.Rainwater harvesting and moisture conservation treatments increased growth of T. ramosissima, tree height was significantly higher for the rainwater harvesting and moisture conservation treatments than the controls. Tree height, crown diameter and collar girth for the T6 treatments increased by 70, 57 and 79% as compared to the controls. No significant differences in crown diameter and collar girth were observed between T1, T2 and T3 or T4 and T5 treatments in some years. The effectiveness of the different treatments for the tree height, crown diameter and collar girth was in the order of T6, T5, T4, T3, T2 and T1.     

Purification,structural elucidation and antitumor activity of a novel mannogalactoglucan from the fruiting bodies of Lentinus edodes

A mannogalactoglucan, named LE-MGG, was isolated from the basidiocarps of Lentinus edodes by hot water-extraction, ethanol precipitation anion exchange chromatography, and further purified by gel-permeation chromatography (GPC). Its structural features were investigated by high performance liquid chromatography (HPLC), high performance gel-permeation chromatography (HPGPC), methylation analysis, periodate oxidation-Smith degradation, and by IR and NMR spectroscopy, including two-dimensional (2D) NMR. HPLC analysis revealed that LE-MGG contained mannose–galactose–glucose in the molar ratio of 10:18:72. GPC and HPGPC showed that LE-MGG was a homogeneous fraction (d = 1.34) and its molecular weight was estimated to be 18 kDa. Chemical and spectroscopic studies indicated that LE-MGG consists of (1 → 6)-, (1 → 4)- and (1 → 3)-linked β-d-glucopyranosyl residues, (1 → 6)-linked α-d-galactopyranosyl residues, (1 → 3,6)- and (1 → 2,4)-linked α-d-mannopyranosyl residues and terminal residues of β-d-glucopyranosyl. Cytotoxicity assay showed that LE-MGG presented higher antitumor activities against S-180 cell with a dose-dependent manner, and exhibited lower cytotoxicity to carcinoma HCT-116 and HT-29 cells. Our studies showed also that LE-MGG presented antitumor bioactivities on Sarcoma 180 solid tumor cell implanted in Kunming mice. This finding suggests that mannogalactoglucan should be explored as potential antitumor agents and could be potentially applied as a natural antitumor drug.     

Life cycle inventories of roundwood production in northern Wisconsin: Inputs into an industrial forest carbon budget

Carbon budgets are developed to understand ecosystem dynamics and are increasingly being used to develop global change policy. Traditionally, forest carbon budgets have focused on the biological carbon cycle; however, it is important to include the industrial forest carbon cycle as well. The overall objective of this study was to quantify the major carbon fluxes associated with the production of Wisconsin's industrial roundwood, by using life cycle inventory (LCI) methodology to produce an industrial forest carbon budget. To achieve this objective we (1) developed carbon LCIs for the harvest process for three major forest ownerships (state, national, and private non-industrial), (2) developed carbon LCIs for a dimensional lumber and two oriented strand board (OSB) mills and (3) completed a scaled version of 1 and 2 to include more Wisconsin forestlands and to incorporate the other major processes within the industrial forest carbon cycle (e.g. primary mill, secondary mill, product use and product disposal processes of the industrial forest carbon cycle). The carbon budgets for the harvesting process of the Chequamegon-Nicolet National Forest (CNNF), the Northern Highland American Legion State Forest (NHAL), and the non-industrial private forests that participated in the managed forest laws of Wisconsin (MFL-NIPF) were 0.10, 0.18 and 0.11 tonnes C ha⁻¹ year⁻¹), respectively. The dimensional lumber and OSB products were both net carbon sources, and released 0.05–0.09 tonnes C/tonnes C processed). More carbon is sequestered than released within the industrial forest carbon cycle of Wisconsin's national (6 g C m⁻² year⁻¹), state (12 g C m⁻² year⁻¹) and non-industrial private forests (7 g C m⁻² year⁻¹). Using published net ecosystem production data we estimate that the net forest carbon cycle budget (sum of the biological and industrial C cycle, [Gower, S.T., 2003. Patterns and mechanisms of the forest carbon cycle. Ann. Rev. Environ. Resour. 28, 169–204]) for the CNNF ranges between −897 and 348 g C m⁻² year⁻¹. Life cycle inventories of wood and paper products should be clear and explicitly state what processes are included, so that results can be used by policy makers and future researchers.     

Chemical constituents from Aphanamixis grandifolia

Four new terpenoids, nemoralisins D–G (1–4), were isolated from the leaves and stems of Aphanamixis grandifolia, along with two known diterpenoids, nemoralisin C and nemoralisin. Among them, compound 1 is the first example of norsesquiterpenoid with δ-lactone moiety, and nemoralisins E–G (2–4), are a class of acyclic diterpenoids, which are structurally related nemoralisin C and nemoralisin. These structures were established on the basis of spectroscopic methods and the absolute configuration of 1 was determined by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Nemoralisins D–G (1–4) were tested for their cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 human tumor cell lines (IC₅₀ > 40 μM), as well as the antimicrobial activities on Staphylococcus aureus, Pseudomonas aeruginosa, MRSA92^# and MRSA98^# (MIC > 50 μg/mL).     

Long-term growth and ecophysiological responses of a southeastern Oklahoma loblolly pine plantation to early rotation thinning

A thinning levels study was initiated in a 9-year-old loblolly pine (Pinus taeda L.) plantation containing 26.6 m² ha⁻¹ basal area during the spring of 1984 in southeastern Oklahoma. Thinning treatments consisted of (1) three control plots (BA100), (2) three plots thinned to approximately 50% of the original basal area (BA50) and (3) three plots that were thinned to 25% of the original basal area (BA25). In 1987 the BA50 and BA25 plots were both rethinned to a basal area of 12 m² ha⁻¹. No other thinnings were done through age 24.The control plots have attained a basal area of 45.3 m² ha⁻¹ and basal area is now starting to decline. The BA25 and BA50 plots have basal areas between 34 and 35 m² ha⁻¹. Mortality has averaged about 90 trees ha⁻¹ per year from age 10 to age 24 on the control plot, declining from 2078 trees ha⁻¹ at age 10 to 827 trees ha⁻¹ at age 24. Mortality losses in the BA25 and BA50 plots have been only 3.2–7.7 trees ha⁻¹ per year over the entire study period. Cumulative stem biomass lost to mortality was 10.5, 16.0 and 61 Mg ha⁻¹, respectively, for the BA25, BA50 and BA100 treatments. Cumulative standing live biomass at age 24 in the BA100 treatment is 132 Mg ha⁻¹. Cumulative standing live biomass in the BA25 and BA50 treatments at age 24 is 86 and 79%, respectively, of that observed in the BA100 treatment. These results suggest wide ranges of residual stand densities left after an early thinning will produce a high percentage of the potential total maximum standing stem biomass. Diameter distributions at age 24 show only 33% of the trees in the BA100 treatments have the dimensions to be sawtimber (≥30 cm) but 92 and 95% of the trees in the BA25 and BA50, respectively, are sawtimber dimension or larger. Mean annual stem biomass production (MAI) of the BA100 treatment is 7.5 Mg ha⁻¹ per year at age 24. MAI of the thinned treatments is about 5.1 Mg ha⁻¹ per year and is converging to that of the BA100 treatment. The basis for this convergence is not that the live trees in the BA100 treatment are producing live biomass less rapidly than the thinned plots, but that mortality losses in the BA100 plot are much higher. Current annual stemwood production in all treatments is often limited by the severe summer droughts that occur in this region. The wide variations in weather experienced at this site also result in variations in earlywood:latewood ratio and ring specific gravity.