No abstract

Dibalik kelezatannya, nyatanya cokelat (kakao) memerlukan daya olah yang tidak sederhana. Barangkali sebagian besar dari kita juga tidak tahu bahwa biji cokelat Indonesia sering dihargai rendah di skala pasar internasional. Suatu paradoks sebetulnya mengingat Indonesia termasuk enam besar negara pemasok kakao di dunia. Apa yang sebenarnya terjadi? Mengapa harga biji kakao asal Indonesia masih rendah dibandingkan kakao dari negara lain? Bagaimana petani kakao dapat berperan maksimal dalam meningkatkan kualitas biji kakaonya sehingga dalam tataran nasional bukan tidak mungkin perekonomian negara juga akan semakin meningkat. Temukan jawaban selengkapnya dalam buku ini. Runutan uraian—dari mengapa biji kakao Indonesia rendah, variatif persoalan yang dihadapi petani kakao Indonesia, jenis-jenis kakao hingga bagaimana mengolah biji kakao dalam tiap tahapnya yang akan berdampak pada cita rasa dan aroma cokelat yang dihasilkan—dijelaskan secara singkat dan padat dalam buku ini. Oleh karena itu, buku ini cocok dibaca oleh siapa saja yang tertarik mengungkap fenomena persoalan cokelat Indonesia serta bagaimana solusi yang tepat untuk mengurai persoalan-persoalan yang ada.

With the uncontrolled spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), development and distribution of antiviral drugs and vaccines have gained tremendous importance. This study focused on two viral proteases namely main protease (Mpro) and papain-like protease (PLpro) and human angiotensin-converting enzyme (ACE-2) to identify which of these are essential for viral replication. We screened 102 secondary metabolites against SARS-CoV-2 isolated from 36 terrestrial plants and 36 marine organisms from Indonesian biodiversity. These organisms are typically presumed to have antiviral effects, and some of them have been used as an immunomodulatory activity in traditional medicine. For the molecular docking procedure to obtain Gibbs free energy value (∆G), toxicity, ADME and Lipinski, AutoDock Vina was used. In this study, five secondary metabolites, namely corilagin, dieckol, phlorofucofuroeckol A, proanthocyanidins, and isovitexin, were found to inhibit ACE-2, Mpro, and PLpro receptors in SARS-CoV-2, with a high affinity to the same sites of ptilidepsin, remdesivir, and chloroquine as the control molecules. This study was delimited to molecular docking without any validation by simulations concerned with molecular dynamics. The interactions with two viral proteases and human ACE-2 may play a key role in developing antiviral drugs for five active compounds. In future, we intend to investigate antiviral drugs and the mechanisms of action by in vitro study.

Tuberculosis (TB) is an airborne illness generated by Mycobacterium tuberculosis (Mtb), also one of the prominent infectious killers of adults worldwide. There is a pressing need to expand novel anti-mycobacterial drugs because of the increasing resistance of pathogenic mycobacteria to existing antibiotics. Native compounds acquired from microbial resources and medicinal cultivars have played an essential part as the origin of TB medications. The microplate resazurin reduction assay (MRRA) is generally utilized to assess natural and synthetic compounds for anti-mycobacterial activity. In our work, the MRRA method was employed to evaluate the antimycobacterial activity of extracts from curative plants using Mycobacterium smegmatis and Mycobacterium bovis BCG and to compare them to rifampicin as an anti-mycobacterial drug. The optimized MRRA utilized 2% aqueous DMSO and 62.5μg/mL resazurin as an indicator compound in 5% aqueous Tween 80. The optimal incubation time for M. smegmatis was 24h, and for M. bovis BCG was 48h. The methanolic plant extracts were acquired from various Indonesian medicinal plants known to have anti-mycobacterial activity. The various plant extracts exhibited anti-mycrobial activities confirmed by the MRRA assay. The MRRA method using M. smegmatis or M. bovis BCG as antimycobacterial targets offers a distinct advantage such as low-cost, rapid, and safe screening for anti-mycobacterial activity in a middle to high-through-putformat.

Mannosylerythritol Lipids (MEL's) are glycolipid biosurfactants that contain 4-O-β-D-mannopyranosylmeso-erythritol as a hydrophilic moiety and fatty acids as a hydrophobic moiety. MEL's are abundantly produced by several kinds of microorganism and are one of the most promising biosurfactants currently known. The search for a novel endogenous producer of MEL's was undertaken based on the available collection of the yeast strains from the genus Pseudozyma. Using thin layer chromatography and based on morphological and molecular taxonomic analysis using the D1/D2 domains of the large subunit 26S rRNA gene, Pseudozyma hubeiensis Y10BS025 was found to be a potential producer of MEL's from soybean oil. The structure of the major glycolipid produced by the strain was analyzed by 1 H and 13 C nuclear magnetic resonance and was found to be similar to those of well known MEL-A, -B and -C respectively. Under improved shaking culture conditions, using yeast extract as nitrogen source and soybean oil as substrate, a maximum yield of 115±3.2 g.L −1 of MEL's for 8 days of fermentation was achieved. The major fatty acids of MEL's produced by P. hubeiensis Y10BS025 were C-18 acids, considerably different from those of MEL-C produced by other Pseudozyma strains such as P. antarctica and P. shanxiensis. The main product, MEL-C produced by P. hubeiensis Y10BS025 exhibited surface-tension-lowering activity. The results demonstrated that the newly isolated P. hubeiensis Y10BS025 provided high efficiency in MEL's production and would thus be highly advantageous in commercial production of promising biosurfactants.