Effect Of Initial Moisture Content And Storage Time On Appearance And Chemical Quality Of Dried Orthosiphon stamineus Leaves. Norawanis Abdul Razak 1, Abdul Razak Shaari 1* and Aldrin Felix Anak Simbas 1 School of Bioprocess Engineering Universiti Malaysia Perlis (UniMAP), Kompleks Pusat Pengajian Jejawi 3, Arau, Perlis, Malaysia. INTERNATIONAL CONFERENCE ON ENGINEERING AND MANAGEMENT 2014 (IPCEM 2014) 25 January 2014

INTRODUCTION During this past decade, interest in herbal medicines has been increasing in Malaysia. Pharmacies are now carrying an abundance of herbal remedies, more recently referred to as dietary supplements, in addition to over-the-counter and prescription drugs.

The quality or shelf life of Malaysia herbal medicines seems to be set arbitrarily. Batches of plant material are not individually tested for their stability, instead a more general assessment is conducted and applied to several batches of pills. The expiration dates for these batches are typically between 2 and 3 years.

Since herbal medicines are produced in large quantities and must then be transported for distribution, the consumers who are using these remedies often do not know how long the plants have been stored or how effective their treatment might be. Only a small number of species of Malaysia plants has been screened for biological activity, and even smaller has been assessed for retention of this activity over time, so that there is little scientific literature available as basis for making decisions about dates of expiry.

The factors [1] that may affect the quality of the raw material during storage are: 1. Moisture content 2. Temperature 3. Humidity 4. Light 5. Packing material

OBJECTIVE This study was conducted in order to assess the effect of initial moisture content and storage time on the appearance (color and moisture content) and chemical (phenolic content andantioxidant) quality of dried O. stamineus leave. Orthosiphon stamineus is believed able to treat chronic diseases such as diabetes, cancer [2,3], gout, kidney stones, high blood pressure, fever, and more [4,5,6].

MATERIAL AND METHOD O. stamineus Cultivation 1.Plants were grown at Institute of Sustainable Agrotechnology (INSAT), UniMAP. 2.Plant propagation by stem cutting was applied. 3.Chicken manure and compound NPK=10:10:10 were utilized as a fertilizer. 4.The first crop collection was done after 10 weeks of cultivation. Orthosiphon stamineus plant

Drying and Sorting. 1.Clean water was used to remove any dirt and dry soil from the harvested O. stamineus plant. 2.A small bundle of fresh plants was tied neatly and hanged under shed for 5 days at least. 3.Dried leaves were sorted from stems. Dried plant

Storage Treatment. 1.The experiment was designed as randomized complete design (RCD). 2.About 10g of dried samples with three different initial moisture contents (7, 10, 13%) were stored at room temperature (25°C). 3.Three different rooms were utilized as a treatment replication. The samples were analyzed starting from 10 days until 40 days. Sample with desired initial moisture content

Extraction of Sample gram of dried leaves was mixed with100ml of distilled water and incubated at 40°C for 3 hours in shaking water bath at 200ppm 2.Each solution was filtered using filter paper (Whatman No.1) and was kept in a sealed bottle and stored in a freezer (-20°C) for further analysis. Samples solution

Colour Analysis. 1.Six readings were taken from individual sample of dried leaves while still in the transparent sealable sample plastic bag using colour meter. 2.The collected data was analyzed by CIELAB color chart Colour analysis CIELAB color chart

Moisture Content Analysis. 1.The moisture analyzer was utilized in collecting of moisture content value in each sample. 2.The data then were collaborated with oven method curve to obtain more accurate reading of moisture content. Moisture analysis

Total Phenolic Content Analysis µl of Follin-Ciocalteu reagent and 200µl sample was mixed to 1.58 ml distilled water. 2.After 4 minutes, 1 ml of 20% sodium carbonate was mixed together. 3.The mixture solution was allowed to incubate for 2 hours in a dark place. 4.The absorbance was read at λ =760nm using uv-vis. Caffeid acid was used as standard. FC technique

Antioxidant Capacity Analysis 1.2 ml of 2,2-diphenyl-1-picrylhydrazyl (DPPH) was mixed with 200 µl sample. Methanol was used to mark up the mixture to 3 ml. 2.The mixture solution was allowed to incubate in a room temperature for 1 hour. 3.The absorbance was read at λ =517nm using uv-vis. % Antioxidant capacity = (Ac-As)/ Ac Ac = Absorbance of the control. As = Absorbance of the sample DPPH technique

Table 1: Effect of initial moisture content and storage time on sample’s moisture. Treatment code Moisture content (%) Initial moisture content (%) Time of storage (days) High a ab bc c Medium d d d d Low e e d d RESULT & DISCUSSION Treatment with different code letters are significantly different at P<0.05

The highest value of moisture content was obtained by a treatment 1 and 2 with the value of and 13.03%, respectively. Meanwhile, the treatment 5, 6, 7, 8, 11 and 12 exhibited the lowest value of moisture content with the value range of 8.59 to 10.00%. The changes of moisture content occurred according to the phenomenon of absorbance and desorption of water. Treatment code Moisture content (%) Initial moisture content (%) Time of storage (days) High a ab bc c Medium d d d d Low e e d d Table 1: Effect of initial moisture content and storage time on sample’s moisture. Treatment with different code letters are significantly different at P<0.05

At high initial moisture content, the water content in dried leaves was desorbed to the environment until equilibrium moisture content achieved. At low initial moisture content, the water content from environment was absorbed into the dried leaves until equilibrium moisture content reached. From the results, the range value of 9.99 to 10.61% could be considered as equilibrium moisture content because all the changes were moving at that range value. Treatment code Moisture content (%) Initial moisture content (%) Time of storage (days) High a ab bc c Medium d d d d Low e e d d Table 1: Effect of initial moisture content and storage time on sample’s moisture. Treatment with different code letters are significantly different at P<0.05

Table 2 : Effect of initial moisture content and storage time on lightness (L*), greeness (a*) and redness (b*) of samples Treatment code L*a*b* Initial moisture content (%) Time of storage (days) High a 1.40 a 8.95 a a 1.22 abcd 7.83 abc a 1.29 abc 8.24 ab a 1.09 abcd 8.31 ab Medium a 1.01 bcd 7.93 abc a 1.11 abcd 7.38 bc a 1.24 abcd 7.71 bc a 0.91 d 8.28 ab Low a 0.92 cd 7.53 bc a 1.35 ab 6.90 c a 0.92 cd 6.79 c a 1.12 d 8.24 ab Treatment with different code letters are significantly different at P<0.05

Generally, from statistical analysis, the treatments significantly (P 0.05) affect the changes of value L* and a*. From table 2, b* value in treatment 1 was significantly different from b* values in treatment 10 and 11. Treatment code L*a*b* Initial moisture content (%) Time of storage (days) High a 1.40 a 8.95 a a 1.22 abcd 7.83 abc a 1.29 abc 8.24 ab a 1.09 abcd 8.31 ab Medium a 1.01 bcd 7.93 abc a 1.11 abcd 7.38 bc a 1.24 abcd 7.71 bc a 0.91 d 8.28 ab Low a 0.92 cd 7.53 bc a 1.35 ab 6.90 c a 0.92 cd 6.79 c a 1.12 d 8.24 ab Table 2 : Effect of initial moisture content and storage time on lightness (L*), greeness (a*) and redness (b*) of samples Treatment with different code letters are significantly different at P<0.05

However, the different between these values represented the yellowness of the dried leaves. The higher of b* value, the more yellow color appeared on dried leaves of O. stamineus. Treatment code L*a*b* Initial moisture content (%) Time of storage (days) High a 1.40 a 8.95 a a 1.22 abcd 7.83 abc a 1.29 abc 8.24 ab a 1.09 abcd 8.31 ab Medium a 1.01 bcd 7.93 abc a 1.11 abcd 7.38 bc a 1.24 abcd 7.71 bc a 0.91 d 8.28 ab Low a 0.92 cd 7.53 bc a 1.35 ab 6.90 c a 0.92 cd 6.79 c a 1.12 d 8.24 ab Table 2 : Effect of initial moisture content and storage time on lightness (L*), greeness (a*) and redness (b*) of samples Treatment with different code letters are significantly different at P<0.05

The yellowness of dried leaves might reduce the customer attraction to buy product. Thus, for marketing strategy, the appearance of the food products should be a priority. The value of a* and L* represented the redness and lightness of the dried leaves. Bad cosmetic appearanceGood cosmetic appearance

Figure 1 : Effect of initial moisture content and storage time on total phenolic content of samples

The highest values were obtained by treatment 2, 5, 6, 8, 9, 10 and 12 in a range value of to mg/g dry weight basis. From Figure 1, the changes of total phenolic content could be considered as not consistent by time. However, the value of total phenolic content could be maintained until day 20, then decreased by time. Figure 1 : Effect of initial moisture content and storage time on total phenolic content of samples

Figure 2 : Effect of initial moisture content and storage time on antioxidant capacity

Statistically, the changes of antioxidant capacity not affected by all treatments (p>0.05). They were consistent by time. The range value obtained was high which not less than 74%. The reduction of total phenolic content did not impact the percentage of antioxidant capacity. Figure 2 : Effect of initial moisture content and storage time on antioxidant capacity

CONCLUSION From this study, we can conclude that the treatments of initial moisture content and storage time exhibited the impact on moisture content, total phenolic content and the yellowness of dried leaves color. But, the changes of total phenolic content were not consistent during storage. The increasing value of total phenolic content gave a good advantage in term of product quality.

However, the color changes of dried O. stamineus leaves should be considered too because it is important factor in attracting the attention of customer to buy the product. Acknowledgement This study sponsored by the Ministry of Higher Education Malaysia (Grant code : FRGS ). References 1.S.D. Lin, J.M. Sung and C.L. Chen, Effect of drying and storage conditions on caffeic acid derivatives and total phenolics of Echinacea Purpurea grown in Taiwan, Food chemistry. 125(2011) R. Hegnauer, Chemotaxonomic der Planzen (Vol. IV), Stuggart: Birkha¨user Verlag. (1966) H. Wangner, Parmazietische Biologie: drogen und ihre Inhaltsstoffe 2nd ed. (1982) D.M. Bwin, U.S. Gwan, Ministry of health, health and Myanmar traditional medicine. In: Burmese Indigenous Medicinal Plant: 1. Plants With Reputed Hypoglycemic Action, Burma Medical Research Institute, Yangon. (1967)126– P.T. Eisai, Indonesia Medicinal Herb Index in Indonesia, 2nd ed, Godjah Mada University Press. (1995) 239– S. Awale, Y. Tezuka, A.H. Banskota, I.K. Adnyana, S. Kadota, Nitric oxide inhibitory isopimarane-type diterpenes from Orthosiphon stamineus of Indonesia, Journal of Natural Products. 66 (2003)