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Introduction To Polymers

Surfactants are compounds that can reduce the surface tension between two different phases or the interfacial tension of the liquid between water and oil, possessing both hydrophilic and hydrophobic moieties. Biosurfactants have traits that have proven to be advantageous over synthetic surfactants, but these compounds do not compete economically with synthetic surfactants. Different alternatives increase the yield of biosurfactants; development of an economical production process and the usage of cheaper substrates during process have been employed. One of the solutions relies on the suitable formulation of a production medium by including alternative raw materials sourced from agro-wastes, hydrocarbons, or by-products of a process might help in boosting the biosurfactant production. Since the nutritional factors required will be different among microorganisms, the establishment of a suitable formulation for biosurfactant production will be challenging. The present review describes various nutrients and elements considered in the formulation of a production medium with an approach focusing on the macronutrient (carbon, nitrogen source, and C/N ratio), minerals, vitamins, metabolic regulators, and salinity levels which may aid in the study of biosurfactant production in the future.

https://www.mdpi.com/1420-3049/23/5/1049/pdf

Culture Medium Development for Microbial-Derived Surfactants Production—An Overview

Phenol-formaldehyde (PF) resin continues to dominate the resin industry more than 100 years after its first synthesis. Its versatile properties such as thermal stability, chemical resistance, fire resistance, and dimensional stability make it a suitable material for a wide range of applications. PF resins have been used in the wood industry as adhesives, in paints and coatings, and in the aerospace, construction, and building industries as composites and foams. Currently, petroleum is the key source of raw materials used in manufacturing PF resin. However, increasing environmental pollution and fossil fuel depletion have driven industries to seek sustainable alternatives to petroleum based raw materials. Over the past decade, researchers have replaced phenol and formaldehyde with sustainable materials such as lignin, tannin, cardanol, hydroxymethylfurfural, and glyoxal to produce bio-based PF resin. Several synthesis modifications are currently under investigation towards improving the properties of bio-based phenolic resin. This review discusses recent developments in the synthesis of PF resins, particularly those created from sustainable raw material substitutes, and modifications applied to the synthetic route in order to improve the mechanical properties.

Bio-Based Alternatives to Phenol and Formaldehyde for the Production of Resins

Advancements in polymer science and engineering have helped the scientific community to shift its attention towards the use of environmentally benign materials for reducing the environmental impact of conventional synthetic plastics. Biopolymers are environmentally benign, chemically versatile, sustainable, biocompatible, biodegradable, inherently functional, and ecofriendly materials that exhibit tremendous potential for a wide range of applications including food, electronics, agriculture, textile, biomedical, and cosmetics. This review also inspires the researchers toward more consumption of biopolymer-based composite materials as an alternative to synthetic composite materials. Herein, an overview of the latest knowledge of different natural- and synthetic-based biodegradable polymers and their fiber-reinforced composites is presented. The review discusses different degradation mechanisms of biopolymer-based composites as well as their sustainability aspects. This review also elucidates current challenges, future opportunities, and emerging applications of biopolymeric sustainable composites in numerous engineering fields. Finally, this review proposes biopolymeric sustainable materials as a propitious solution to the contemporary environmental crisis. • Use of biopolymers has emerged as a new paradigm of the ecological conservation. • Biopolymeric composites are easily degraded under the possible source of degraded environment. • Biopolymers have found their applications in biomedical, food, electronics, cosmetics and other emerging fields. • Further understanding on their mode of action through this comprehensive review will imparts knowledge. 

Biopolymeric Sustainable Materials and their Emerging Applications

Rhamnolipids are a class of biosurfactants with effective surface-active properties. The high cost of microbial production of rhamnolipids largely affects their commercial applications. To reduce the production post, research has been carried out in screening more powerful strains, engineering microbes with higher biosurfactant yields and exploring cheaper substrates to reduce the production cost. Extensive refining is required for biosurfactant production using oils and oil-containing wastes, necessitating the use of complex and expensive biosurfactant recovery methods such as extraction with solvents or acid precipitation. As raw materials normally can account for 10–30% of the overall production cost, sugars have been proven to be an alternative carbon source for microbial production of rhamnolipids due to its lower costs and straightforward processing techniques. Studies have thus been focused on using tropical agroindustrial crop residues as renewable substrates. Herein, we reviewed studies that are using sugar-containing substrates as carbon sources for producing rhamnolipids. We speculate that sugars derived from agricultural wastes rich in cellulose and sugar-containing wastes are potential carbon sources in fermentation while challenges still remain in large scales.

/pdf/microbial-production-of-rhamnolipids-using-sugars-as-carbon-3bjp4gqche.pdf

Microbial production of rhamnolipids using sugars as carbon sources

This study aims to determine the effect of germination time on the antioxidant activity of Leucaena leucocephala (lmk.) de Wit (lead tree) sprouts. Determination of antioxidant activity was carried out on ethanol extract of germinated seeds using β-carotene bleaching assay. The results showed that the antioxidant activity of germinated seeds were affected by germination time. Germination for 4 days affected the greatest enhancement in antioxidant activity by 2.78 fold and caused a significant increment in total phenolic content by 7.29, β-carotene by 3.27, ascorbic acid by 3.81 and α-tocopherol by 4.58 fold, respect to imbibed seeds. The total phenolics content was 53.42±0.22 mg CAE/g dw, β-carotene was 530.99±71.13 10-3 mg/100 g, ascorbic acid was 152.37±2.06 mg/100 g, and α-tocopherol was 59.27±0.10 mg/100 g sample. The findings suggested that the L. leucocephala sprouts could be considered as a source of natural antioxidant.

Effect of germination on antioxidant activity, total phenolics, β-carotene, ascorbic acid and α-tocopherol contents of lead tree sprouts (Leucaena leucocephala (lmk.) de Wit).

A molasses based medium for the biosurfactant production by Pseudomonas fluorescens was developed, where the effect of pre-treated of molasses and medium composition were evaluated. Biosurfactant production was followed by measuring optical density (OD), surface tension and emulsifying index (E24) over 12 days of fermentation. The optimum condition for the biosurfactant production was obtained when a medium containing of 8 g/L nutrient broth, 5 g/L NaCl, 1 g/L NH4NO3 and 5% v/v pre-treated molasses with centrifugation was used as media with 3 days of fermentation. The biosurfactant was identified as a rhamnolipid type biosurfactant which had critical micelle concentration (CMC) value of 801 mg/L and was able to reduce the surface tension of the water from 80 mN/m to 51 mN/m. The biosurfactants had water in oil (w/o) emulsion type. Biosurfactant was able to emulsify various hydrocarbons, which were able to decrase the interfacial tension about 50-75% when benzyl chloride, anisaldehyde and palm oil were used as immiscible compounds. The biosurfactant exhibited the E24 value of about 50% and the stable emulsion was reached up to 30 days when lubricant was used as an immiscible compound. Up to 68% of phenol was degraded in the presence of biosurfactant within 15 days, whereas only 56% of phenol was degraded in the absence of biosurfactant. Overall, the results exhibited that molasses are recommended for the rhamnolipids production which possessed good surface-active properties and had potential application in the enhancement of phenol degradation.

Biosurfactant production by Pseudomonas fluorescens growing on molasses and its application in phenol degradation

. Suryanti V, Kusumaningsih T, Marliyana SD, Setyono HA, Trisnawati EW. 2020. Identification of active compounds and antioxidant activity of teak (Tectona grandis) leaves. Biodiversitas 21: 941-947. Teak (Tectona grandis) grows in tropical area and the teak wood is widely used for building construction and furniture. Young teak leaf contains red pigment and often are used for natural food coloring. The research objectives were to isolate the young teak leaf chemical compounds and to investigate their antioxidant activities. The compounds identification was carried out by UV-Vis Spectroscopy, GC-MS and LC-MS. The antioxidant activity determination was carried out by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) method. The total phenolics content was determined using Folin-Ciocalteu method and total anthocyanins content was examined using the H-differential method. Two fractions were observed further by UV-Vis Spectroscopy, GC-MS and LC-MS. The UV-Vis spectrum of FA confirmed the presence of anthocyanins which has maximum absorbance at 208 and 492 nm. The GC-MS spectrum of fraction A (FA) revealed 4-hydroxy-4-methyl-2-pentanone, glycerin monoacetate, glycerin diacetate and 1-eicosanol. The UV-Vis spectrum of FC also confirms the presence of anthocyanins which has maximum absorbance at 489 nm. The LC-MS spectrum of fraction C (FC) shows anthocyanins, namely malvidin-3-o- (6-o-acetyl)-5-o-diglucoside. The FA and FC teak leaf fractions have strong antioxidant activities as their IC50 values are less than 50 ppm. Total phenolic of teak leaf extract was 6.17 mg GAE/g and total anthocyanins of teak leaf extract were 67.5 mg/L.

https://smujo.id/biodiv/article/download/5154/3705

Identification of active compounds and antioxidant activity of teak (Tectona grandis) leaves

Biosurfactant with efficient emulsification properties could be produced by Pseudomonas flourescens using cassava flour wastewater (manipueira) as media. The ability of P. flourescens to produce biosurfactant could suggest potential use in industrial and environmental applications. Media containing a mixture of natural manipueira and nutrient broth with 48 h fermentation was the optimum condition for the biosurfactant production. Based on UVVis and FT-IR spectra, the biosurfactant was indicated as rhamnolipids containing hydroxyl, ester, carboxylic and aliphatic carbon chain functional groups. Biosurfactant exhibited critical micelle concentration (CMC) value of 715 mg/L and reduced the surface tension of the water from 80 mN/m to 59 mN/m. The biosurfactant was able to decrease the interfacial tension about 51-70% when benzyl chloride, palm oil and kerosene were used as waterimmiscible compounds. The biosurfactant was able to form stable emulsion until 30 days when paraffin, soybean oil, lubricant oil and kerosene were used as water-immiscible compounds.

https://jurnal.ugm.ac.id/ijc/article/download/21281/13986

PRODUCTION AND CHARACTERIZATION OF BIOSURFACTANT BY Pseudomonas fluorescens USING CASSAVA FLOUR WASTEWATER AS MEDIA

Temu glenyeh (Curcuma soloensis. Val) is one of the medicinal plants that grow in Surakarta. This plant is similar with C. longa and C. Xanthoriza. Chemical constituents from an extract of the plant have never been studied. In this paper, we report the isolation of a terpenoid and curcumin from the rhizome of C. soloensis. The isolation was employed by soxhlet apparatus using acetone as solvent. The fractionation and purification of the compound from the acetone extracts were undertaken by vacuum liquid chromatography and flash chromatography. Identification of compounds used spectroscopy methods, such as FTIR, NMR (1H NMR, 13C NMR, COSY, HSQC and HMBC) and GC-MS. Isolated compounds were identified as curcumin (1) and bisacurone (2).

https://iopscience.iop.org/article/10.1088/1757-899X/107/1/012063/pdf

Soerya Dewi Marliyana

Papers

Effect of germination on antioxidant activity, total phenolics, β-carotene, ascorbic acid and α-tocopherol contents of lead tree sprouts (Leucaena leucocephala (lmk.) de Wit).

Biosurfactant production by Pseudomonas fluorescens growing on molasses and its application in phenol degradation

Identification of active compounds and antioxidant activity of teak (Tectona grandis) leaves

PRODUCTION AND CHARACTERIZATION OF BIOSURFACTANT BY Pseudomonas fluorescens USING CASSAVA FLOUR WASTEWATER AS MEDIA

Isolation and identification of curcumin and bisacurone from rhizome extract of temu glenyeh (Curcuma soloensis. Val)