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Hydrolysis and fermentation conditions for production of ethanol from very high-gravity cassava mash by Saccharomyces cerevisiae during simultaneous saccharification and fermentation (SSF) processing were optimized using a statistical methodology. During the first part of the study, Placket–Burman design (PBD) was used to study 19 factors that could potentially influence ethanol production. Gravity, particle size, initial pH, and fermentation temperature were identified as key factors that significantly increased final ethanol concentration. The main and interaction effects of these factors were subsequently evaluated based on a quadratic equation generated by central composite design (CCD) using response-surface methodology (RSM). Under the optimized very high-gravity conditions, the final ethanol concentration obtained from experiment increased from 8.21% (wt.%) to 15.03% (wt.%) and was in good agreement with model prediction. By employing two other commercial Saccharomyces strains, similar results were obtained under the same optimized condition. Therefore, we conclude that final ethanol concentration, ethanol productivity (V P/max), glucose utilization (Y G/s, Y P/s), and fermentation efficiency (η f) were enhanced or maintained under the optimized condition of 40% gravity, 390 μm particle size, initial pH 5.5, and 27°C fermentation temperature.

In addition to eleven known lignans, eight new compounds including 8-hydroxypluviatolide, 5,8-dihydroxypluviatolide, two benzofuran-type neolignans, three lignans bearing oxy substituents at the C-2 positions and a γ-piperonylmethyl-γ-butenolide were isolated from the leaves of Taiwania cryptomerioides Hayata. Their structures were determined by spectroscopic methods.

Five new diterpenes and four uncommon sterols were isolated from the leaves of Taiwania cryptomerioides. Their structures were determined by chemical, spectroscopic and X-ray diffraction methods. The terpenes are 8,9-epoxy-7-oxoroyleanone methyl ether, 1,13,14-trihydroxypodocarpa-8,11,13-trien-7-one, 7α,8α-dihydroxylabda-13(16),14-dien-19-yl cis-4-hydroxycinnamate, 7α,8α-dihydroxylabda-13(16),14-dien-19-yl trans-4-hydroxycinnamate and beyer-15-en-18-carboxy β- d -glucopyranoside pentaacetate. The sterols, namely taiwaniasterols A-D, exhibit an uncommon skeleton of 6-5-6-5 fused rings.

Seven new compounds were isolated from the leaves of Taiwania crypomerioides. Taiwaniaquinone D and taiwaniaquinone E are diterpenes having a six-five-six fused ring skeleton. Taiwaniadduct A is a [4 + 2] cycloaddition product of β-myrcene and taiwaniaquinone A. Taiwaniadduct B and taiwaniadduct C are isomers derived from [4 + 2] cycloadditions of trans-ozic acid and taiwaniaquinone A. Taiwaniadduct D is formally an ene reaction product of taiwaniadduct B. Taiwaniadduct E is a [5 + 2] cycloaddition product of taiwaniaquinone A and trans-ozic acid. The structure determination of these new compounds was based on spectral analyses and chemical transformation. A crystalline compound, prepared by bismethylation of taiwaniadduct D, was analysed by X-ray diffraction to establish the stereochemistry.

Four diterpenoid aldehydes and one norditerpenoid ketone having the uncommon skeleton of six-five-six fused-rings were isolated from the leaves of Taiwania crytomerioides .