In the present work, the lengthy synthesis duration of zeolite-T was successfully reduced by inducing the ultrasonic pre-treatment method prior to hydrothermal growth. The effect of ultrasonic pre-treatment durations on the formation of zeolite-T was investigated. The structure and morphology of the resultant samples were characterized by FTIR, XRD and FESEM. As verified by FTIR, samples produced using synthesis durations of 5, 4, 3 and 2 days with ultrasonic pre-treatment durations of 60 min and 90 min, respectively, demonstrated zeolite-T structure. One day synthesis duration was not sufficient for the formation of zeolite-T. From the results obtained by XRD and FESEM, it was found that samples underwent 60 min ultrasonic pre-treatment produced zeolite-T with higher crystallinity, while no significant changes on the morphology of the resultant zeolite-T synthesized using ultrasonic pre-treatment durations of 60 min and 90 min.

Extraction is crucial for herbal extraction to ensure high quality of bioactive compounds from natural herbs. In the current work, Zingiber Zerumbet was extracted via subcritical water extraction (SWE) and is compared with the conventional solvent extraction, Soxhlet. The quality of the extract was investigated in terms of zerumbone concentration, radical scavenging activity (RSA) and total phenolic content (TPC). For zerumbone concentration, extraction via SWE gave 19.82 ±0.004 mg/g as compared with Soxhlet; 28.51±0.079 mg/g. However, the extraction time required for SWE to yield such concentration only required 40 minutes instead of Soxhlet which took 480 minutes. The same trend was recorded for RSA, which yielded 60.70±0.070% inhibition for SWE and 68.81±0.024% inhibition from Soxhlet extraction. In contrast to TPC, SWE recorded a higher response than Soxhlet extraction, which was 19.19±0.003 mgGAE/g DW, while Soxhlet; 8.30±0.019 mgGAE/g DW. Therefore, the SWE method is more favorable for obtaining a higher value of TPC, slightly good in antioxidant properties but lower zerumbone concentration value than organic solvent extraction. However, the reduced extraction time was almost 12 times quicker for SWE when compared with Soxhlet extraction. Overall, SWE is a promising alternative environmentally friendly since it only uses water as solvent and is comparable to the conventional method.

Over the past eight decades, numerous research has been conducted on the extraction of Zingiber zerumbet rhizome. The mini-review includes information on the pharmacological properties of zerumbone extracted from Z. zerumbet rhizome and the extraction methods conducted over the previous 80 years. Zerumbone is recognised as having a proven pharmacological effect and is a significant medicinal component used to treat various ailments. The pharmacological values are stated based on the research findings. The extraction method and technology are essential to extract zerumbone. Thus, the review helps the reader keep up with the history of each technique or technology used in extracting zerumbone from Z. zerumbet rhizome, starting with conventional technology and moving toward advanced technology.

Zingiber zerumbet (Z. zerumbet) or locally called ‘lempoyang’ is one of the ginger species extensively cultivated and utilized in the Southeast Asia region. In order to extract valuable ingredients from Z. zerumbet, a green and non-toxic extraction process is implemented namely subcritical water extraction (SWE). Modeling and optimization of SWE of Z. zerumbet are performed using the central composite design (CCD) by 20 runs with 6 repetitions at the center point. The independent variables investigated in this research are temperature (130-170°C), time of extraction (20-40 minutes) and solid to solvent ratio (20-40 ml/g) that focused to identify the optimized process parameters for zerumbone concentration, antioxidant activity, and yield of extracts. All independent variables researched were analyzed to be significant as the p-value for zerumbone concentration, antioxidant activity and yield are 0.0001, which are less than 0.05 for a model to be significant. The optimum process parameters for all responses of Z. zerumbet extract are at 170°C, 20 minutes and 20 ml/g. This optimum condition was validated and the correlation between predicted and experimental values was within 95% which indicated the range of variables selected was valid. Thus, the outcome from this research may be beneficial on subcritical water extraction of ginger species especially Z. zerumbet.

The purpose of this study is to investigate the medicinal properties of Moringa oleifera (M. oleifera) leaves towards xanthine oxidase inhibitory activity by using water-based extraction methods such as boiling extraction, subcritical water extraction (SWE) and ultrasonic-assisted extraction (UAE). Boiling extraction is chosen as the control method in this study due to its commonly used in the industry. Water based extraction is investigated to determine if it can replace the conventional extraction method which uses organic solvent and time consuming. Temperature and time were investigated using central composite design (CCD) for maximum xanthine oxidase inhibitory activity in SWE and UAE. The boiling extraction is operated at fixed temperature of 100 °C while SWE is utilised at temperature of 100 to 180 °C and UAE at 30 to 60 °C with same time within 10 to 30 min. These variables are used to determine optimum condition on each method for xanthine oxidase inhibitory activity of M. oleifera leaves, then compared with the control method to identify ideal method of extraction. Thus, SWE (69.65 ± 0.1 %) at 180 °C and 20 min is the ideal method compared to UAE (48.89 ± 0.3 %) at 60 °C and 30 min and boiling extraction (41.88 ± 0.1 %) at 100 °C and 20 min due to higher percentage of xanthine oxidase inhibitory activity obtained on M. oleifera leaves. The findings of this study show that SWE offer better alternative for M. Oleifera extraction towards xanthine oxidase inhibitory compares to other methods.