Prof. Erly began her lecture by reminding the audience that life on Earth depends on plants. Through photosynthesis, carbon dioxide and water are converted—with the help of sunlight—into sugar and oxygen. This sugar is the primary building block for forming other compounds that serve as raw materials for bioproducts—that is, materials derived from renewable biomass that are processed using technology into value-added products.

“Plants are not merely a source of biomass. Within every plant cell, orderly biochemical reactions or metabolism take place,” she said.

Subway Line Inside the Cell

According to Prof. Erly, plant metabolism is regulated by a dynamic system. Stimuli such as light, temperature, or drought are detected by sensors on the cell membrane and then transmitted through a signaling pathway that activates or suppresses genes encoding enzymes. These reactions form a network that she likens to a subway system, complete with numerous routes, intersections, and transfer points. From this network come carbohydrates, proteins, and lipids that serve as ingredients for food, medicine, cosmetics, and even bioenergy.

This principle can be harnessed through tissue culture and by regulating the ratio of auxin to cytokinin. In potatoes, small bud cuttings from tubers planted in a cytokinin-rich medium can be propagated into hundreds of new plants in a short time. These plants are uniform and pathogen-free; they are then acclimatized to produce tubers for seed, consumption, or use as raw materials for bioproducts.

From Rice Paddy Algae to Sambiloto

Prof. Erly also presented her research on the freshwater alga Spirogyra, which is abundant in ponds and rice fields. This alga contains astaxanthin, a red antioxidant pigment, as well as lipids. In a controlled bioreactor, the addition of an oxidative stress inducer increased the expression of genes in the astaxanthin biosynthesis pathway, causing its concentration to rise 3- to 6-fold compared with the control group. High salinity increased lipid yield by 47 percent and the concentration of omega-3 fatty acids in Spirogyra by 22 percent.

She applied a genetic engineering approach to sambiloto to increase levels of the active compound andrographolide. The team increased the expression of the HMGR gene—a key gene in the mevalonate biosynthesis pathway—through Agrobacterium-mediated transformation. As a result, gene expression increased approximately 50-fold, leading to the accumulation of the target compound.

A Cup of Coffee and a Metabolite Map

Prof. Erly then turned her attention to the metabolomics of West Java Robusta coffee. Using GC-MS, her team identified 143 metabolites from samples collected in Bogor and the East Priangan region, including Sumedang, Kuningan, Tasikmalaya, and Ciamis. The metabolite profile of Bogor coffee was clearly distinct from that of East Priangan coffee, and these differences were related to temperature, rainfall, and growing altitude.

Taste tests revealed these effects. Bogor coffee, grown at a temperature of 26°C, an elevation of 700 meters above sea level, and an annual rainfall of 4,300 mm, achieved a cupping score of 65.5 (commercial quality) with signature compounds such as benzaldehyde and caffeine. Ciamis coffee, grown at temperatures of 27–31°C, an elevation of 400–600 meters above sea level, and a maximum annual rainfall of 3,200 mm, achieved a score of 82.5 (premium quality) with characteristic compounds such as isovaleric acid and acetic acid.

For farmers, she recommends cultivation at temperatures of 27–31°C, altitudes no higher than 650 meters above sea level, and annual rainfall no greater than 3,200 mm to achieve premium quality. For researchers, these two characteristic compounds serve as a starting point for metabolic engineering to produce premium coffee.

Damaged Cilembu Sweet Potatoes, Leftover Sugar

The lecture concluded with an example of agricultural waste utilization. Cilembu sweet potatoes are often infested by the boleng pest, causing them to be damaged and become unsellable—even though they still contain starch. Prof. Erly’s team processed them into sweet potato syrup through starch extraction, liquefaction using alpha-amylase, and then saccharification with glucoamylase. The sweetness level is equivalent to that of commercial liquid sugar.

She emphasized that understanding plant biosynthetic pathways and biochemical composition serves as the foundation for identifying strategic points that can be activated or inhibited—including for transforming waste into valuable products.

“An understanding of metabolic regulation, together with the application of metabolic engineering, can support the sustainable development of plant-based raw materials for bioproducts to meet needs for food, health, and bioenergy,” she said.

Profile of Prof. Dr. Erly Marwani, M.S.

Prof. Dr. Erly Marwani, M.S., was born in Bandung on October 5, 1962. She is a Full Professor in the Plant Science and Biotechnology Group at the School of Life Sciences and Technology (SITH), ITB. She completed her bachelor’s and master’s degrees in Biology at ITB in 1986 and 1990, respectively, and earned her Ph.D. in Applied Bioscience and Biotechnology from Okayama University, Japan, in 1997.

Since 1988, she has served as a faculty member at the School of Life Sciences and Technology (SITH) at ITB. At the undergraduate level, she teaches courses such as Plant Physiology, Plant-Based Bioproduct Technology, and Metabolic Engineering, and is one of the pioneering instructors in the Bioengineering Study Program. At the master’s level, she teaches Plant Cell and Tissue Engineering and Bioprospecting. She has supervised 70 undergraduate students, 18 master’s students, and 2 doctoral students, both as the primary advisor and as a member of the advisory committee.

In the field of research, Prof. Erly has secured 22 research grants—3 at the national level and 19 within ITB—serving as either principal investigator or a research team member. Her productivity is also reflected in 29 scientific publications, comprising 20 international and 9 national publications as first or co-author, as well as one utility model and one Intellectual Property Right (IPR).

In the area of institutional development, she has served as Deputy Head of General Administration and Finance at CBSED (2004–2005), Secretary of the Master’s Program in Biotechnology (2005–2006), Chair of the Bioengineering Study Program (2017–2018), and Chair of the Doctoral Program in Biology (2018–2020). From 2023 to 2025, she led the management of the Laboratory of Bioprocesses, Transformation, and Analysis of Natural Materials. Outside the campus, she is active in community service in Sumedang and East Kalimantan and serves as an assessor for BAN-PT and LAM.

In recognition of her dedication, she received the Satyalancana Karya Satya 30-Year Award in 2019 and a 35-year service award from ITB in 2023.