Siasatan terhadap taburan dan kelimpahan kumpulan pemakanan
makroinvertebrata akuatik di Sungai Bogak, Kerian dan Serdang di lembangan sungai
Kerian menunjukkan terdapat 120 genera dari 59 keluarga dari 13 order makroinvertebrata.
Pemangsa terutamanya Odonata, Hemiptera dan Coleoptera adalah kumpulan yang paling
biasa dan didapati dalam kepadatan tinggi di Sungai Bogak (sungai yang diubah suai)
dan Sungai Kerian (sungai utama). Kumpulan dominan kedua di kedua-dua sungai itu
adalah pemungut-kumpul (Diptera dan Ephemeroptera) diikuti oleh pengikis (moluska).
Pola kumpulan pemakanan yang berlainan diperhatikan di Sungai Serdang (anak Sungai
Kerian). Kumpulan yang paling banyak adalah pemungut-kumpul, diikuti oleh pemangsa
dan pengikis. Secara umum, kelimpahan pemangsa menunjukkan korelasi positif dengan
kelimpahan mangsa mereka (kumpulan pemakanan lain). Kelimpahan pemangsa terutama
di Sungai Bogak dan Kerian, sangat dipengaruhi oleh parameter seperti PO43-, NO3-N
dan Zn. Kelimpahan pemungut-kumpul di sungai Serdang pula dipengaruhi oleh suhu
dan halaju air, TSS, kekeruhan serta kandungan Mn dan Cu di dalam sedimen. Walau
bagaimanapun, semua parameter air mempengaruhi secara lemah kelimpahan kumpulan
pemakanan di semua lokasi. Banyak pemungut-kumpul di Sungai Serdang dikaitkan dengan
air yang diperkaya oleh sisa antropogenik dari kawasan kediaman sekitar. Pada umumnya,
kumpulan pemakanan yang dominan di setiap sungai mencerminkan pengaruh keadaan
persekitaran yang berbeza dan ketersediaan sumber makanan di kawasan tersebut
A study was conducted on the chemical and biological properties of three different species of Mangifera i.e. Mangifera pajang, M. indica L., and M. kemanga leaves obtained from Pitas, Sabah. The aims of this study were to determine the presence of secondary metabolites as well as the antioxidative activities especially the catalase (CAT) and guiacol peroxidase specific activities (gPOD) in the leaves part of these three species. The extraction of these samples was carried out using three different polarities of solvents: hexane, ethyl acetate, and methanol. The total percentage of the crude extract of is 7.30% for M. pajang, 12.87% for M. indica and 7.98% for M. kemanga. Phytochemical screening was performed with various tests for each of the crude extracts. The results showed that these three species gave positive results for alkaloids, saponins, flavonoids, phenols, carbohydrates, phytosterols, and tannins metabolites. Based on the tests, CAT specific activities were significantly higher in the leaves of M. pajang with 4.35 ± 1.18 units/mg protein compared to M. indica L. and M. kemanga. The guaiacol peroxidase (gPOD) specific activities showed that M. indica L. has the highest activity with the value of 0.0047 ± 0.0004 units/mg protein.
local herb known as neem (semambu) or its scientific name Azadirachta indica has been used extensively in traditional treatment due to its medicinal properties. Neem leaves have been used traditionally for treating several epidermal dysfunctions, such as eczema, psoriasis, and acne. Neem is rich in antioxidants and helps to boost immune response in tissues of affected skin area. It also consists of bioactive compounds for antibacterial, antifungal, and anticancer activities. In this study, neem leaves extract was used in producing herbal neem soap as a remedy for curing skin problems. The herbal neem soap was made by blending 36.4% palm oil, 9.1% coconut oil, 27.3% sodium hydroxide, 9.1% neem oil extract, and 18.2% neem aqueous extract which formed a pale yellow soap base. The results of the selected physical and chemical properties of this study show that the moisture content of the soap was 4.02% with 10.60 pH value, 57.40% total fatty matter, and 0.44% free caustic alkali. The results imply that herbal neem soap is suitable for human skin and can be a therapeutic alternative to skin problems.
The syntheses of salicylideneaniline (L1a) and 4-hydroxybenzalaniline (L1b) was carried out via condensation reaction giving yields of 80.74% and 81.65% respectively. The compounds were characterised by physical and spectroscopic techniques, namely melting point, micro elemental analysis (C, H and N), 1H Nuclear Magnetic Resonance (NMR) and Infrared (IR) spectroscopy. The characteristic n(C=N) peaks were observed at 1615 cm-1 and 1575 cm-1 respectively. Chronoamperometry (CA) was employed to electrodeposit both compounds on mild steel at 0.1 M inhibitor concentration in 0.3 M NaOH at three different potentials, +0.8 V, +1.05 V and +1.7 V. Formation of yellow imine films was observed on the mild steel. The corrosion behaviour of coated and uncoated mild steel was studied using Linear Polarization Resistance (LPR) in 0.5 M NaCl. Coated mild steel showed better corrosion resistance and with the highest inhibition efficiency of 90.34%, L1a provides a better protection against corrosion for mild steel than L1b.
This study investigates the effect of oxalic acid at different concentrations as doping agent on
the electrical properties of polyaniline (PANI). The polymerization of aniline to produce
PANI was carried out in media containing oxalic acid at 0.08 M, 0.09 M, 0.1 M, 0.2 M and
0.3 M in the presence of ammonium persulphate as oxidizing agent. The successful formation
of PANI doped with oxalic acid was confirmed by FTIR and the morphology studied using
XRD. An impedance investigation on the series of PANI formed revealed that doping in 0.1M
oxalic acid produced PANI of the highest conductivity of 2.52 x 10-6
Scm-1.
Orthopedic implants are an important tool in the treatment of musculoskeletal conditions and helped many patients to improve their quality of life. Various inorganic-organic biocomposites have been broadly investigated particularly in the area of load-bearing orthopedic/dental applications. Polyimide (PI) is a promising organic material and shows excellent mechanical properties, biocompatibility, bio-stability, and its elastic modulus is similar to human bone but it lacks bioactivity, which is very important for cell adhesion and ultimately for bone regeneration. In this research, tantalum pentoxide (Ta2O5) coating was prepared on the surface of PI by polydopamine (PDA) bonding. The results showed that Ta2O5 was evenly coated on the surface of PI, and with the concentration of Ta2O5 in the PDA suspension increased, the content of Ta2O5 particles on the surface of PI increased significantly. In addition, the Ta2O5 coating significantly increased the roughness and hydrophilicity of the PI matrix. Cell experiments showed that PI surface coating Ta2O5 could promote the proliferation, adhesion, and osteogenic differentiation of bone marrow-derived stromal cells (BMSCs). The results demonstrated that fabricating Ta2O5 coating on the surface of PI through PDA bonding could improve the biocompatibility as well as bioactivity of PI, and increase the application potential of PI in the field of bone repair materials.
Phytochemical investigation on the bark of E. kingiana plant afforded ten compounds, including six polyketides namely kingianin A 1, kingianin B 2, kingianin E 3, kingianin F 4, kingianin K 5 and kingianin L 6, three endiandric acids; kingianic acid A 7, tsangibeilin B 8 and endiandric acid M 9, and one sesquiterpene; daibuoxide 10. All compounds were separated as racemic mixture by recycling high-performance liquid chromatography (RHPLC), except for daibuoxide. Their structures were elucidated by detailed spectroscopic and comparative literature data analysis. This is the first report on the presence of the sesquiterpene; daibuoxide in Endiandra genus. In vitro enzymatic bio-evaluation of the isolated compounds against α-amylase and α-glucosidase showed that 4 demonstrated the best α-amylase and α-glucosidase inhibitory activity with IC50 values of 181.54 ± 6.27 µg/mL and 237.87 ± 0.07 µg/mL, respectively. In addition, molecular docking analysis confirmed the α-amylase and α-glucosidase inhibitory activities demonstrated by 4.
The diversity and abundance of macroinvertebrate shredders were investigated in 52 forested streams (local scale) from nine catchments (regional scale) covering a large area of peninsular Malaysia. A total of 10,642 individuals of aquatic macroinvertebrates were collected, of which 18.22% were shredders. Biodiversity of shredders was described by alpha (αaverage), beta (β) and gamma diversity (γ) measures. We found high diversity and abundance of shredders in all catchments, represented by 1,939 individuals (range 6-115 and average per site of 37.29±3.48 SE) from 31 taxa with 2-13 taxa per site (αaverage=6.98±0.33 SE) and 10-15 taxa per catchment (γ=13.33±0.55 SE). At the local scale, water temperature, stream width, depth and altitude were correlated significantly with diversity (Adj-R2=0.205). Meanwhile, dissolved oxygen, stream velocity, water temperature, stream width and altitude were correlated to shredder abundance (Adj-R2=0.242). At regional scale, however, water temperature was correlated negatively with β and γ diversity (r2=0.161 and 0.237, respectively) as well as abundance of shredders (r2=0.235). Canopy cover was correlated positively with β diversity (r2=0.378) and abundance (r2=0.266), meanwhile altitude was correlated positively with β (quadratic: r2=0.175), γ diversity (quadratic: r2=0.848) as well as abundance (quadratic: r2=0.299). The present study is considered as the first report describing the biodiversity and abundance of shredders in forested headwater streams across a large spatial scale in peninsular Malaysia. We concluded that water temperature has a negative effect while altitude showed a positive relationship with diversity and abundance of shredders. However, it was difficult to detect an influence of canopy cover on shredder diversity.