Pengaruh Leverage, Good Corporate Governance, dan Pertumbuhan Laba terhadap Kualitas Laba Perusahaan yang Terindeks Jakarta Islamic Indeks di Bursa Efek Indonesia

This research is entitled Analysis Leverage, Good Corporate Governance (GCG), and Profit Quality on Earnings Quality in Companies listed on the Indonesia Stock Exchange (IDX) and indexed by the Jakarta Islamic Index (JII). This research was conducted because the previous research was mostly conducted on companies listed on the Indonesia Stock Exchange, while only a few were conducted on companies indexed by the Jakarta Islamic Index so that research was very open, by adding variables namely profit quality and earnings quality. The purpose of this study was to determine the direct effect on earnings quality in companies indexed by the Jakarta Islamic Index.The population of this study are companies listed and indexed by the Jakarta Islamic Index on the Indonesia Stock Exchange, while the samples used are financial reports for 2018-2020. The sampling method was carried out using purposive sampling method. The number of samples obtained was 90 company data listed on the Indonesia Stock Exchange and indexed by the Jakarta Islamic Index (30 companies and an observation period of 3 years, namely 2018-2020). The data analysis method used by the author is multiple linear regression analysis method both partially and simultaneously using SPSS 23. The results showed that partially leverage has a significant effect on earnings quality, good corporate governance has a significant effect on earnings quality and earnings quality has a significant effect on earnings quality, while simultaneously showing that leverage, good corporate governance, and earnings quality have a significant effect on earnings quality.

Purification and Characterization of Laccase from Some Wood Rotting Fungi

Laccase is an enzyme that hydrolyzes lignin ending towards production of glucose. It has many applications in pharmaceutical, paper and pulp industry, food industry and textile industry. These diverse requirements act as a license for the evolution of practicable biotechnological applications for the large scale production of laccase enzyme to cover up the local industrial demands. This target can be accomplished through assortment, adaptation and utilization of home grown biological sources. In present study, Pleurotus ostreatus (jacq.) P. Kumm., Ganoderma lucidum (Curtis) P. Karst., Ganoderma ahmadii Steyaert, Ganoderma applanatum Conk., Ganoderma australe (Fr.) Pat, Ganoderma colossus (Fr.) C. F. Baker, Ganoderma flexipes Pat., Ganoderma resinaceum Bourd., Ganoderma tornatum (Persoon) Bresadola, Coriolus hirsutus (Wulfen) Pilat, Coriolus proteus (Berk.) Dutta Roy, Coriolus pubescens (Trametes pubescens (Schum: Fr.) Pil), Coriolus tephroleucus (Trametes tephroleuca Berk.), Coriolus versicolor (Fr. ex Fr.) Quel, Trametes insularis Murr., Coriolus zonatus (Nees) Quél, Fomes fomentarius (L. ex. Fr.) Fr., Fomes scruposus (Fr.) G. H. Cunn., Fomitopsis semitostus (Berk.) Ryv., Fomes lividus (Kalchbr.) Sacc., Fomes linteus (Berk. and Curt.), Phellinus allardii (Bres.) Ahmad, Phellinus badius (Berk. Cke.) Cunn., Phellinus callimorphus (Leveille) Ryvarden, Phellinus caryophylli (Racib.) G. Cunn., Phellinus pini (Thore: Fr.) Ames, Phellinus torulosus (Pers.) Boud. Galz., Poria ravenalae (Berk. and Br.) Cooke, Poria versipora (Pers.) Rom., Poria paradoxa (Schizopora paradoxa (Schrad.:Fr.) Donk,), Poria latemarginata (Durieu & Mont.) Cooke, Heterobasidion insulare (Murrill) Ryvarden sensu lato, Schizophyllum commune (Fr.), Schizophyllum radiatum (Sw.) Fr. Daldinia sp. (Ces.)De not., Xylaria sp. (Pres.) Grev., were collected, isolated, identified and then screened qualitatively for their laccase activity. After qualitative screening, potential strains were screened quantitatively for laccase activity on effluents of different plant based industries. Growth and nutritional conditions were optimized for the best producer to enhance the laccase activity. Scale up studies were carried out on optimized conditions for production of enzyme followed by purification and characterization of enzyme. The stepwise findings are: · Qualitative assay analysis revealed that the all test fungi possess good ability for synthesis of laccase enzyme at pH 5.5 on MEA media alongwith ABTS. · Quantitative bioassays on ME broth showed that selected fungi i.e., P. ostreatus 008, P. ostreatus 016, G. lucidum 101, G. lucidum 102 and G. lucidum 104 showed high potential towards production of laccase enzyme, so selected for further trials. · The selected wood rotting fungi were tested for their laccase potential on different industrial effluents i.e., oil and ghee mill effluent, paper and pulp mill effluent, sugar mill effluent and textile mill effluent and G. lucidum 101 gave best enzyme units (24.34 U mL-1). · Growth and nutritional conditions were optimized with paper and pulp mill effluent for enhanced production of laccase by G. lucidum 101. The optimized parameters were: incubation temperature; 30 ᴼC, incubation period; 16 days, initial pH; 5, inoculum’s size; 15 disks (5mm diameter), Cellulose (as carbon source); 3.5%, urea (as nitrogen source); 4 mg mL-1, 300 mM copper Sulfate and ethanol 3% with the synthesis of 51.45 U mL-1 of laccase. · After optimization of growth and nutrition conditions on shake flask, scale up studies were carried out for 10 liter of sterilized effluent in bioreactor of 50 liter capacity on same growth and nutritional conditions as optimized for shake flask. The laccase activity was 7800 U 10L-1. · The enzyme was isolated and purified through 80% ammonium sulfate precipitation, followed by DEAE-cellulose and then Sephadex G-100 column chromatography. The protein purity was 5.23 folds with molecular weight of 78 ± 2 KDa. · Kinetic evaluation of enzyme revealed maximum laccase activity was achieved at pH 5 with 100% stability till 120 minutes. Thermal stability was 100% at 60 ᴼC at the exposure time of 60 minutes. The values of MichealisMenton constant Km and Vmax were 0.3 mM and 80 mM/min with ABTS substrate. HgCl2, Pb(No3)2, sodium azide and mercaptethanol inhibited the laccase activity fully or partially whereas CuSO4 and MnSo4 acted as enzyme activator. All the findings were discussed depending upon the fact that fungi are potential source of enzymes and the industrial effluents may act as cheaper substrate for the production of these enzymes at industrial level. This effort concluded that indigenous fungi have potential for the production of laccase enzyme and after optimizing growth and nutritional conditions large scale production of the enzyme can be carried out.