Tree slenderness coefficient at Bali Botanic Garden

Standing trees has a higher risk regarding structural damage that can cause trees or parts of trees to fail. Meanwhile, Bali Botanic Garden is located in a highland area that periodically gets natural disasters such as heavy wind. However, the information on tree stability is little known. Therefore, tree stability at Bali Botanic Garden was assessed using tree slenderness coefficient (SC) as an indicator. Purposive sampling technique was adopted for locations which highly visited. A total of 624 trees with dbh>40 cm were examined as samples. Trees were classified based on their SC as high (>80), moderate (SC:70-80), low (SC<70). Data were analyzed using descriptive and correlation analysis. Tree slenderness coefficient at Bali Botanic Garden classified as low (609 specimens), medium (11 specimens), and high (4 specimens). Trees with the high category were three individuals of Bischofia javanica Blume (SC=82.76, 83.69, and 89.63) and a Syzygium polyanthum (Wight) Walp. (SC=116.13). Trees with high SC had a higher susceptibility to wind-induced damage. There was a negative correlation between SC and others tree parameters except for tree height (r=0.44). Hence appropriate silvicultural treatment like thinning is recommended to enhance better tree development and minimize tree risk.

Antioxidant and Anti-Inflammatory Effects of Bischofia javanica (Blume) Leaf Methanol Extracts through the Regulation of Nrf2 and TAK1

Bischofia javanica (Blume) has been traditionally used to treat inflammatory diseases such as tonsillitis and ulcers throughout Asia, including China, Indonesia, and the Philippines: however, the molecular mechanisms by which B. javanica exerts its antioxidant and anti-inflammatory properties remain largely unknown. In this study, we analyzed the antioxidant and anti-inflammatory mechanisms of methanol extracts of B. javanica leaves (MBJ) in vitro and in vivo. MBJ decreased nitric oxide (NO) production and the expression of pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α, in lipopolysaccharide (LPS)-treated RAW 264.7 cells. The observed suppression of inflammatory responses by MBJ was correlated with an inhibition of the nuclear factor-κB (NF-κB) and the mitogen-activated protein kinase (MAPK) pathways. Additionally, MBJ induced nuclear translocation of the nuclear factor erythroid 2-related factor 2 (Nrf2), a transcription factor that upregulates the expression of anti-inflammatory and antioxidant genes. Furthermore, MBJ exhibited antioxidant and anti-inflammatory effects in an acute hepatitis mouse model. In conclusion, our results confirm the medicinal properties of B. javanica, and therefore MBJ could be applied to improve inflammatory and redox imbalances in different types of pathologies.

PENENTUAN POTENSI EKSTRAK KULIT BATANG TUMBUHAN SIKKAM (Bischofia javanica Blume) SEBAGAI ANTIOKSIDAN DENGAN METODE DPPH DAN SITOTOKSIK DENGAN METODE BSLT

This study aims to determine the level of antioxidant activity of Sikkam bark extract (Bischofia javanica Blume) and its potential as an anticancer agent. This research was conducted in November 2018 - April 2019 in the Laboratory of Chemical Education Guidance and Counseling and Basic Science Laboratory, University of Bengkulu. The sample in this study was obtained from Gunung Mariah village in Simalungun district, North Sumatra. The method used in this study was extraction using maceration, liquid-liquid fractionation, phytochemical test, DPPH (Diphenylpicrylhiydrazyl) test and BSLT test (Brine Shrimp Lethality Test). Extraction maceration using ethanol 96%, fractionation using a solvent n-hexane and ethyl acetate, phytochemical tests using Mayer's reagent, Lieberman-Burchard, FeCl3 1% and H2SO4 2N, antioxidant test using DPPH (1,1-diphenyl-2-picrylhydrazyl) and cytotoxic tests using shrimp Artemia salina Leach larvae. The results of the study on maceration of 800 grams of Sikkam bark obtained a crude extract of 53.6 grams (6.7%). Fractionation from 10 grams of crude extract obtained 7.24 gram ethanol fraction (72.4%), ethyl acetate fraction 2.14 gram (21.4%) and n-Hexane fraction 0.39 gram (3.9%). Phytochemical test results obtained the content of alkaloids, flavonoids, tannins, saponins and terpenoids with the highest yield on tannin compounds. The antioxidant activity test results obtained IC50 values in crude extracts of 20.94 ppm, ethanol fraction 36.29 ppm, ethyl acetate fraction 83.28 ppm and n-Hexane fraction 39.13 ppm which showed that crude extract, ethanol fraction, n-Hexane fraction were categorized as very strong antioxidants and Ethyl acetate fraction is categorized as a strong antioxidant. The cytotoxic test results using crude extract obtained an LC50 value of 54,827 ppm which showed that Sikkam bark extract was toxic so that it was potential as an anticancer agent.

Outstanding performance of an invasive alien tree Bischofia javanica relative to native tree species and implications for management of insular primary forests

Invasive alien tree species can exert severe impacts, especially in insular biodiversity hotspots, but have been inadequately studied. Knowledge of the life history and population trends of an invasive alien tree species is essential for appropriate ecosystem management. The invasive tree Bischofia javanica has overwhelmed native trees on Haha-jima Island in the Ogasawara Islands, Japan. We explored forest community dynamics 2 years after a typhoon damaged the Sekimon primary forests on Haha-jima Island, and predicted the rate of population increase of B. javanica using a logistic model from forest dynamics data for 19 years. During the 2 years after the typhoon, only B. javanica increased in population size, whereas populations of native tree species decreased. Stem diameter growth of B. javanica was more rapid than that of other tree species, including native pioneer trees. Among the understory stems below canopy trees of other species, B. javanica grew most rapidly and B. javanica canopy trees decreased growth of the dominant native Ardisia sieboldii. These competitive advantages were indicated to be the main mechanism by which B. javanica replaces native trees. The logistic model predicted that B. javanica would reach 30% of the total basal area between 2017 (in the eastern plot adjacent to a former B. javanica plantation) and 2057 (in the western plot distant from the plantation site), which is a maximum percentage allowing to eradicate under the present guideline of the National Forest. The results suggest immediate removal of B. javanica is required to preserve native biodiversity in these forests.