The aim of this study is to evaluate chemical and biological profile of methanol extracts from Malaysian propolis produced by two commonly found stingless bee species, Heterotrigona itama (MHI) and Geniotrigona thoracica (MGT). Test samples were analyzed for physicochemical parameters such as moisture, fat, crude fibre, crude protein, carbohydrate and ash content. Tests for phytochemical screening by thin layer chromatography of both extracts revealed that presence of terpenoids, flavonoids, phenols and essential oils but steroids, saponin and coumarins only occur in MHI. Both extracts displayed a characteristic profile and vary from each other. Accordingly, MHI possess higher antioxidant activity with an IC 50 of 15.0 ± 0.21 ug/mL compared to MGT with IC 50 of 270.0 ± 0.19 ug/mL. MHI showed moderate nitric oxide scavenging activity, while MGT only showed mild inhibition. Antidiabetic activity was determined by α-glucosidase inhibition and found significantly better than that of acarbose (positive control). In conclusion, data gathered in this study revealed that bee species play role in determining the chemical and biological profile of particular propolis and should put into account in decision of further development for propolis.Keywords: physico-chemical, phytochemical, TLC profiling, antioxidant, antidiabetic Abstrak Tujuan kajian ini adalah untuk menilai profil kimia dan biologi ekstrak metanol propolis dari Malaysia yang dihasilkan oleh dua species lebah kelulut yang biasa dijumpai, Heterotrigona itama (MHI) dan Geniotrigona thoracica (MGT). Sampel telah dianalisis untuk parameter fizikokimia seperti kelembapan, lemak, serat kasar, protein mentah, karbohidrat dan kandungan abu. Pemeriksaan keatas analisis fitokimia menggunakan kromatografi lapisan nipis untuk kedua-dua ekstrak menunjukkan kehadiran terpenoid, flavonoid dan minyak pati tetapi steroid, saponin dan coumarin hanya wujud dalam MHI. Kedua -dua ekstrak menunjukkan profil yang berbeza antara satu sama lain. Sehubungan itu juga, MHI mempunyai aktiviti antioksidan yang lebih tinggi dengan IC 50 15.0 ± 0.21 ug/mL berbanding MGT (270.0 ± 0.19 ug/mL). MHI menunjukkan aktiviti perencatan nitrik oksida yang sederhana, sementara MGT menunjukkan perencatan yang sedikit sahaja. Aktiviti antidiabetik telah ditentukan menggunakan perencatan α-glukosida dan didapati lebih baik secara signifikan daripada acarbose (kawalan positif). Kesimpulannya, data yang dikutip dalam kajian ini menunjukkan bahawa spesies lebah memainkan peranan dalam menentukan profil kimia dan biologi propolis tertentu dan perlu dipertimbangkan dalam membuat keputusan untuk pembangunan propolis. [7]. It is generally accepted that bees collect resinous plant materials, produced by a variety of botanical processes, in different parts of plants.

BackgroundStudies on selected metabolites profiling of Orthosiphon stamineus extracts using chromatographic and spectroscopic techniques combined with chemometric tools have not been fully elucidated. Thus present study was performed to profile selected metabolites in O. stamineus leaves extracts using HPLC and FTIR combined with chemometric tools and correlated with biological activities.MethodsFive different extracts were prepared using three methods; maceration, soxhlet and reflux. The extracts were analyzed using UV-Vis, HPLC and FTIR techniques. Analysis of selected primary and secondary metabolites was also evaluated. The antioxidant and cytotoxic activities of the extracts were evaluated. Chemometric tools were employed to classify the extracts based on HPLC analysis and FTIR fingerprints.ResultsThe ethanolic extract using maceration characterized high content of phenolics and flavonoids, (rosmarinic acid and eupatorin) with high antioxidant activity. Ethanolic (50 %) and methanolic extracts using soxhlet showed high proteins and glycosaponins. Water extracts using reflux and maceration showed high polysaccharides. Methanolic extract (50 %) using soxhlet and methanolic extract using maceration showed strong cytotoxic effect against MCF7 and HCT116 cell lines, respectively. Antioxidant and cytotoxic activities showed significant correlation with selected primary and secondary metabolites. HPLC fingerprints combined with chemometrics showed the extracts have been clustered based on selected major peaks profile. FTIR fingerprints combined with chemometrics showed that the extracts have been clustered based on protein and polysaccharide contents.ConclusionTen different extracts of O. stamineus have showed significant differences in the content of selected primary and secondary metabolites as well as the biological activities. Chemometric tools were able to classify and discriminate the distinctive features of extracts thus can be correlated with the biological activities.

Hydrogen peroxide (H2O2) is defined as a reactive oxygen species (ROS), able to cause damage to a variety of cellular structures. On the other hand, recent work has demonstrated that H2O2 can also act as a potent signaling molecule that mediates various physiological and biochemical processes in plants. This study was carried out to investigate the effects of H2O2 on the growth, mineral nutrient accumulation, as well as the biologic and chemical properties of Ficus deltoidea var. deltoidea. F. deltoidea plants were spray-treated with 0- (control), 8-, 16-, 30- and 60-mM H2O2 under field conditions. Plant height, leaf area, chlorophyll content, net photosynthetic rate, stomatal conductance and quantum yield of the F. deltoidea plants significantly increased after treatment with 16 and 30-mM H2O2. The results indicate that 60-mM H2O2 increased the accumulation of arsenic, iron and sodium content in the leaves of F. deltoidea. On the other hand, 8-mM H2O2 significantly enhanced the accumulation of arsenic, iron, calcium and potassium content in the syconium of F. deltoidea plants. In addition, H2O2 treatment did not produce any significant effects on antimony and magnesium accumulation in the leaves or the syconium of F. deltoidea plants. The results show that the F. deltoidea plant has strong antidiabetic properties and its α-glucosidase activity increased in treated plants compared to standard acarbose. Hydrogen peroxide, particularly in concentrations of 16 and 30 mM, increased the antioxidant activity, total phenolic and flavonoid content and the vitexin and isovitexin content. There was a positive correlation between antioxidant activity with total phenol and total flavonoid content in H2O2-treated plants. The quantitative analysis by HPTLC indicates that the amount of vitexin and isovitexin increased with the higher concentrations of H2O2. From this study, it can be concluded that spraying 16 and 30-mM H2O2 once a week enhances growth, mineral accumulation and stimulates bioactive compounds of the F. deltoidea plants.

Importin-α serves as an adaptor linking importin-β to proteins carrying a nuclear localization sequence (NLS). During interphase, this interaction enables nuclear protein import, while in mitosis it regulates spindle assembly factors (SAFs) and controls microtubule nucleation, stabilization and spindle function. Here, we show that human importin-α1 is regulated during the cell cycle and is phosphorylated at two sites (threonine 9 and serine 62) during mitosis by the major mitotic protein kinase CDK1–cyclin B. Mutational analysis indicates that the mitotic phosphorylation of importin-α1 inhibits its binding to importin-β and promotes the release of TPX2 and KIFC1, which are then targeted like importin-β to the spindle. Loss of importin-α1 or expression of a non-phosphorylated mutant of importin-α1 results in the formation of shortened spindles with reduced microtubule density and induces a prolonged metaphase, whereas phosphorylation-mimicking mutants are functional in mitosis. We propose that phosphorylation of importin-α1 is a general mechanism for the spatial and temporal control of mitotic spindle assembly by CDK1–cyclin B1 that acts through the release of SAFs such as TPX2 and KIFC1 from inhibitory complexes that restrict spindle assembly.